Are all Spring Framework Java Configuration injection examples buggy?
In your test, you are comparing the two TestParent
beans, not the single TestedChild
bean.
Also, Spring proxies your @Configuration
class so that when you call one of the @Bean
annotated methods, it caches the result and always returns the same object on future calls.
See here:
Linker Command failed with exit code 1 (use -v to see invocation), Xcode 8, Swift 3
I k now the question has already been answered. But if this helps somebody save some time :
I had the same error. I checked everything to find a very small and stupid mistake from my side. I imported a core data ManagedObject custom file in a view controller of my project. I accidentally imported the .m file instead of the .h file which was causing the duplicate symbol in architecture error (linker command failed) because my .m file of properties class imports the .h file of core data class and hence causing duplicate import.
So just check if u have imported the right files before you try multiple solutions.!
Golang read request body
Inspecting and mocking request body
When you first read the body, you have to store it so once you're done with it, you can set a new io.ReadCloser
as the request body constructed from the original data. So when you advance in the chain, the next handler can read the same body.
One option is to read the whole body using ioutil.ReadAll()
, which gives you the body as a byte slice.
You may use bytes.NewBuffer()
to obtain an io.Reader
from a byte slice.
The last missing piece is to make the io.Reader
an io.ReadCloser
, because bytes.Buffer
does not have a Close()
method. For this you may use ioutil.NopCloser()
which wraps an io.Reader
, and returns an io.ReadCloser
, whose added Close()
method will be a no-op (does nothing).
Note that you may even modify the contents of the byte slice you use to create the "new" body. You have full control over it.
Care must be taken though, as there might be other HTTP fields like content-length and checksums which may become invalid if you modify only the data. If subsequent handlers check those, you would also need to modify those too!
Inspecting / modifying response body
If you also want to read the response body, then you have to wrap the http.ResponseWriter
you get, and pass the wrapper on the chain. This wrapper may cache the data sent out, which you can inspect either after, on on-the-fly (as the subsequent handlers write to it).
Here's a simple ResponseWriter
wrapper, which just caches the data, so it'll be available after the subsequent handler returns:
type MyResponseWriter struct {
http.ResponseWriter
buf *bytes.Buffer
}
func (mrw *MyResponseWriter) Write(p []byte) (int, error) {
return mrw.buf.Write(p)
}
Note that MyResponseWriter.Write()
just writes the data to a buffer. You may also choose to inspect it on-the-fly (in the Write()
method) and write the data immediately to the wrapped / embedded ResponseWriter
. You may even modify the data. You have full control.
Care must be taken again though, as the subsequent handlers may also send HTTP response headers related to the response data –such as length or checksums– which may also become invalid if you alter the response data.
Full example
Putting the pieces together, here's a full working example:
func loginmw(handler http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
body, err := ioutil.ReadAll(r.Body)
if err != nil {
log.Printf("Error reading body: %v", err)
http.Error(w, "can't read body", http.StatusBadRequest)
return
}
// Work / inspect body. You may even modify it!
// And now set a new body, which will simulate the same data we read:
r.Body = ioutil.NopCloser(bytes.NewBuffer(body))
// Create a response wrapper:
mrw := &MyResponseWriter{
ResponseWriter: w,
buf: &bytes.Buffer{},
}
// Call next handler, passing the response wrapper:
handler.ServeHTTP(mrw, r)
// Now inspect response, and finally send it out:
// (You can also modify it before sending it out!)
if _, err := io.Copy(w, mrw.buf); err != nil {
log.Printf("Failed to send out response: %v", err)
}
})
}
Why I can't access remote Jupyter Notebook server?
I got the same problem but none of workarounds above work for me. But if I setup a docker version jupyter notebook, with the same configuration, it works out for me.
For my stituation, it might be iptables rule issues. Sometimes you may just using ufw
to allow all route to your server. But mine just iptables -F
to clear all rule. Then check iptables -L -n
to see if its works.
Problem fixed.
how to make a new line in a jupyter markdown cell
"We usually put ' (space)' after the first sentence before a new line, but it doesn't work in Jupyter."
That inspired me to try using two spaces instead of just one - and it worked!!
(Of course, that functionality could possibly have been introduced between when the question was asked in January 2017, and when my answer was posted in March 2018.)
Changing background color of selected item in recyclerview
I made this implementation in kotlin I thing is not very efficient but works
ivIsSelected is a ImageView that represent in my case a check mark
var selectedItems = mutableListOf<Int>(-1)
override fun onBindViewHolder(holder: ContactViewHolder, position: Int) {
// holder.setData(ContactViewModel, position) // I'm passing this to the ViewHolder
holder.itemView.setBackgroundColor(Color.WHITE)
holder.itemView.ivIsSelected.visibility = INVISIBLE
selectedItems.forEach {
if (it == position) {
holder.itemView.setBackgroundColor(Color.argb(45, 0, 255, 43))
holder.itemView.ivIsSelected.visibility = VISIBLE
}
}
holder.itemView.setOnClickListener { it ->
it.setBackgroundColor(Color.BLUE)
selectedItems.add(position)
selectedItems.forEach { selectedItem -> // this forEach is required to refresh all the list
notifyItemChanged(selectedItem)
}
}
}
Why does C++ code for testing the Collatz conjecture run faster than hand-written assembly?
For more performance: A simple change is observing that after n = 3n+1, n will be even, so you can divide by 2 immediately. And n won't be 1, so you don't need to test for it. So you could save a few if statements and write:
while (n % 2 == 0) n /= 2;
if (n > 1) for (;;) {
n = (3*n + 1) / 2;
if (n % 2 == 0) {
do n /= 2; while (n % 2 == 0);
if (n == 1) break;
}
}
Here's a big win: If you look at the lowest 8 bits of n, all the steps until you divided by 2 eight times are completely determined by those eight bits. For example, if the last eight bits are 0x01, that is in binary your number is ???? 0000 0001 then the next steps are:
3n+1 -> ???? 0000 0100
/ 2 -> ???? ?000 0010
/ 2 -> ???? ??00 0001
3n+1 -> ???? ??00 0100
/ 2 -> ???? ???0 0010
/ 2 -> ???? ???? 0001
3n+1 -> ???? ???? 0100
/ 2 -> ???? ???? ?010
/ 2 -> ???? ???? ??01
3n+1 -> ???? ???? ??00
/ 2 -> ???? ???? ???0
/ 2 -> ???? ???? ????
So all these steps can be predicted, and 256k + 1 is replaced with 81k + 1. Something similar will happen for all combinations. So you can make a loop with a big switch statement:
k = n / 256;
m = n % 256;
switch (m) {
case 0: n = 1 * k + 0; break;
case 1: n = 81 * k + 1; break;
case 2: n = 81 * k + 1; break;
...
case 155: n = 729 * k + 425; break;
...
}
Run the loop until n = 128, because at that point n could become 1 with fewer than eight divisions by 2, and doing eight or more steps at a time would make you miss the point where you reach 1 for the first time. Then continue the "normal" loop - or have a table prepared that tells you how many more steps are need to reach 1.
PS. I strongly suspect Peter Cordes' suggestion would make it even faster. There will be no conditional branches at all except one, and that one will be predicted correctly except when the loop actually ends. So the code would be something like
static const unsigned int multipliers [256] = { ... }
static const unsigned int adders [256] = { ... }
while (n > 128) {
size_t lastBits = n % 256;
n = (n >> 8) * multipliers [lastBits] + adders [lastBits];
}
In practice, you would measure whether processing the last 9, 10, 11, 12 bits of n at a time would be faster. For each bit, the number of entries in the table would double, and I excect a slowdown when the tables don't fit into L1 cache anymore.
PPS. If you need the number of operations: In each iteration we do exactly eight divisions by two, and a variable number of (3n + 1) operations, so an obvious method to count the operations would be another array. But we can actually calculate the number of steps (based on number of iterations of the loop).
We could redefine the problem slightly: Replace n with (3n + 1) / 2 if odd, and replace n with n / 2 if even. Then every iteration will do exactly 8 steps, but you could consider that cheating :-) So assume there were r operations n <- 3n+1 and s operations n <- n/2. The result will be quite exactly n' = n * 3^r / 2^s, because n <- 3n+1 means n <- 3n * (1 + 1/3n). Taking the logarithm we find r = (s + log2 (n' / n)) / log2 (3).
If we do the loop until n = 1,000,000 and have a precomputed table how many iterations are needed from any start point n = 1,000,000 then calculating r as above, rounded to the nearest integer, will give the right result unless s is truly large.
Check if date is a valid one
I use moment along with new Date to handle cases of undefined
data values:
const date = moment(new Date("2016-10-19"));
because of: moment(undefined).isValid() == true
where as the better way: moment(new Date(undefined)).isValid() == false
Service located in another namespace
To access services in two different namespaces you can use url like this:
HTTP://<your-service-name>.<namespace-with-that-service>.svc.cluster.local
To list out all your namespaces you can use:
kubectl get namespace
And for service in that namespace you can simply use:
kubectl get services -n <namespace-name>
this will help you.
Run CRON job everyday at specific time
you can write multiple lines in case of different minutes, for example you want to run at 10:01 AM and 2:30 PM
1 10 * * * php -f /var/www/package/index.php controller function
30 14 * * * php -f /var/www/package/index.php controller function
but the following is the best solution for running cron multiple times in a day as minutes are same, you can mention hours like 10,30
.
30 10,14 * * * php -f /var/www/package/index.php controller function
How to change dataframe column names in pyspark?
You can put into for loop, and use zip to pairs each column name in two array.
new_name = ["id", "sepal_length_cm", "sepal_width_cm", "petal_length_cm", "petal_width_cm", "species"]
new_df = df
for old, new in zip(df.columns, new_name):
new_df = new_df.withColumnRenamed(old, new)
Get folder name of the file in Python
You could get the full path as a string then split it into a list using your operating system's separator character.
Then you get the program name, folder name etc by accessing the elements from the end of the list using negative indices.
Like this:
import os
strPath = os.path.realpath(__file__)
print( f"Full Path :{strPath}" )
nmFolders = strPath.split( os.path.sep )
print( "List of Folders:", nmFolders )
print( f"Program Name :{nmFolders[-1]}" )
print( f"Folder Name :{nmFolders[-2]}" )
print( f"Folder Parent:{nmFolders[-3]}" )
The output of the above was this:
Full Path :C:\Users\terry\Documents\apps\environments\dev\app_02\app_02.py
List of Folders: ['C:', 'Users', 'terry', 'Documents', 'apps', 'environments', 'dev', 'app_02', 'app_02.py']
Program Name :app_02.py
Folder Name :app_02
Folder Parent:dev
Swift do-try-catch syntax
enum NumberError: Error {
case NegativeNumber(number: Int)
case ZeroNumber
case OddNumber(number: Int)
}
extension NumberError: CustomStringConvertible {
var description: String {
switch self {
case .NegativeNumber(let number):
return "Negative number \(number) is Passed."
case .OddNumber(let number):
return "Odd number \(number) is Passed."
case .ZeroNumber:
return "Zero is Passed."
}
}
}
func validateEvenNumber(_ number: Int) throws ->Int {
if number == 0 {
throw NumberError.ZeroNumber
} else if number < 0 {
throw NumberError.NegativeNumber(number: number)
} else if number % 2 == 1 {
throw NumberError.OddNumber(number: number)
}
return number
}
Now Validate Number :
do {
let number = try validateEvenNumber(0)
print("Valid Even Number: \(number)")
} catch let error as NumberError {
print(error.description)
}
javax.net.ssl.SSLException: Read error: ssl=0x9524b800: I/O error during system call, Connection reset by peer
Android Supports SSL implementation by default except for Android N (API level 24) and below Android 5.1 (API level 22)
I was getting the error when making the API call below API level 22 devices after implementing SSL at the server side; that was while creating OkHttpClient client object, and fixed by adding connectionSpecs() method OkHttpClient.Builder class.
the error received was
response failure: javax.net.ssl.SSLException: SSL handshake aborted:
ssl=0xb8882c00: I/O error during system call, Connection reset by peer
so I fixed this by added the check like
if ( Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP_MR1) {
// Do something for below api level 22
List<ConnectionSpec> specsList = getSpecsBelowLollipopMR1(okb);
if (specsList != null) {
okb.connectionSpecs(specsList);
}
}
Also for the Android N (API level 24); I was getting the error while making the HTTP call like
HTTP FAILED: javax.net.ssl.SSLHandshakeException: Handshake failed
and this is fixed by adding the check for Android 7 particularly, like
if (android.os.Build.VERSION.SDK_INT == Build.VERSION_CODES.N){
// Do something for naugat ; 7
okb.connectionSpecs(Collections.singletonList(getSpec()));
}
So my final OkHttpClient object will be like:
OkHttpClient client
HttpLoggingInterceptor httpLoggingInterceptor2 = new
HttpLoggingInterceptor();
httpLoggingInterceptor2.setLevel(HttpLoggingInterceptor.Level.BODY);
OkHttpClient.Builder okb = new OkHttpClient.Builder()
.addInterceptor(httpLoggingInterceptor2)
.addInterceptor(new Interceptor() {
@Override
public Response intercept(Chain chain) throws IOException {
Request request = chain.request();
Request request2 = request.newBuilder().addHeader(AUTH_KEYWORD, AUTH_TYPE_JW + " " + password).build();
return chain.proceed(request2);
}
}).connectTimeout(30, TimeUnit.SECONDS)
.writeTimeout(30, TimeUnit.SECONDS)
.readTimeout(30, TimeUnit.SECONDS);
if (android.os.Build.VERSION.SDK_INT == Build.VERSION_CODES.N){
// Do something for naugat ; 7
okb.connectionSpecs(Collections.singletonList(getSpec()));
}
if ( Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP_MR1) {
List<ConnectionSpec> specsList = getSpecsBelowLollipopMR1(okb);
if (specsList != null) {
okb.connectionSpecs(specsList);
}
}
//init client
client = okb.build();
getSpecsBelowLollipopMR1 function be like,
private List<ConnectionSpec> getSpecsBelowLollipopMR1(OkHttpClient.Builder okb) {
try {
SSLContext sc = SSLContext.getInstance("TLSv1.2");
sc.init(null, null, null);
okb.sslSocketFactory(new Tls12SocketFactory(sc.getSocketFactory()));
ConnectionSpec cs = new ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS)
.tlsVersions(TlsVersion.TLS_1_2)
.build();
List<ConnectionSpec> specs = new ArrayList<>();
specs.add(cs);
specs.add(ConnectionSpec.COMPATIBLE_TLS);
return specs;
} catch (Exception exc) {
Timber.e("OkHttpTLSCompat Error while setting TLS 1.2"+ exc);
return null;
}
}
The Tls12SocketFactory class will be found in below link (comment by gotev):
https://github.com/square/okhttp/issues/2372
For more support adding some links below this will help you in detail,
https://developer.android.com/training/articles/security-ssl
D/OkHttp: <-- HTTP FAILED: javax.net.ssl.SSLException: SSL handshake aborted: ssl=0x64e3c938: I/O error during system call, Connection reset by peer
Simple InputBox function
It would be something like this
function CustomInputBox([string] $title, [string] $message, [string] $defaultText)
{
$inputObject = new-object -comobject MSScriptControl.ScriptControl
$inputObject.language = "vbscript"
$inputObject.addcode("function getInput() getInput = inputbox(`"$message`",`"$title`" , `"$defaultText`") end function" )
$_userInput = $inputObject.eval("getInput")
return $_userInput
}
Then you can call the function similar to this.
$userInput = CustomInputBox "User Name" "Please enter your name." ""
if ( $userInput -ne $null )
{
echo "Input was [$userInput]"
}
else
{
echo "User cancelled the form!"
}
This is the most simple way to do this that I can think of.
How to check all versions of python installed on osx and centos
Here is a cleaner way to show them (technically without symbolic links):
ls -1 /usr/bin/python* | grep '[2-3].[0-9]$'
Where grep
filters the output of ls that that has that numeric pattern at the end ($).
Or using find
:
find /usr/bin/python* ! -type l
Which shows all the different (!
) of symbolic link type (-type l
).
How do I use namespaces with TypeScript external modules?
Try this namespaces module
namespaceModuleFile.ts
export namespace Bookname{
export class Snows{
name:any;
constructor(bookname){
console.log(bookname);
}
}
export class Adventure{
name:any;
constructor(bookname){
console.log(bookname);
}
}
}
export namespace TreeList{
export class MangoTree{
name:any;
constructor(treeName){
console.log(treeName);
}
}
export class GuvavaTree{
name:any;
constructor(treeName){
console.log(treeName);
}
}
}
bookTreeCombine.ts
---compilation part---
import {Bookname , TreeList} from './namespaceModule';
import b = require('./namespaceModule');
let BooknameLists = new Bookname.Adventure('Pirate treasure');
BooknameLists = new Bookname.Snows('ways to write a book');
const TreeLis = new TreeList.MangoTree('trees present in nature');
const TreeLists = new TreeList.GuvavaTree('trees are the celebraties');
Remove all items from RecyclerView
This is how I cleared my recyclerview and added new items to it with animation:
mList.clear();
mAdapter.notifyDataSetChanged();
mSwipeRefreshLayout.setRefreshing(false);
//reset adapter with empty array list (it did the trick animation)
mAdapter = new MyAdapter(context, mList);
recyclerView.setAdapter(mAdapter);
mList.addAll(newList);
mAdapter.notifyDataSetChanged();
Java finished with non-zero exit value 2 - Android Gradle
For me the problem was, i had put a unnecessary complie library code in build.gradle
dependencies {
compile 'com.google.android.gms:play-services:7.5.0'
}
which was causing over 65k methods, so removed it,gradle sync, cleaned project, and then ran again and then this error stopped.
I needed just maps and gcm so i put these lines and synced project
compile 'com.google.android.gms:play-services-gcm:7.5.0'
compile 'com.google.android.gms:play-services-location:7.5.0'
Hi people i again encountered this problem and this time it was because of changing build tools version and it really required me to enable multidex..so i added these my app's build.gradle file..
defaultConfig {
applicationId "com.am.android"
minSdkVersion 13
targetSdkVersion 23
// Enabling multidex support.
multiDexEnabled true
}
dexOptions {
incremental true
javaMaxHeapSize "2048M"
jumboMode = true
}
dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
compile 'com.android.support:multidex:1.0.1'
}
And create a class that extends Application class and include this method inside the class..
@Override
protected void attachBaseContext(Context base) {
super.attachBaseContext(base);
MultiDex.install(this);
}
also include in OnCreate method too
@Override
public void onCreate() {
MultiDex.install(this);
super.onCreate();
}
Check if an element has event listener on it. No jQuery
You don't need to. Just slap it on there as many times as you want and as often as you want. MDN explains identical event listeners:
If multiple identical EventListeners are registered on the same
EventTarget with the same parameters, the duplicate instances are
discarded. They do not cause the EventListener to be called twice, and
they do not need to be removed manually with the removeEventListener
method.
Display a RecyclerView in Fragment
I faced same problem. And got the solution when I use this code to call context. I use Grid Layout. If you use another one you can change.
recyclerView.setLayoutManager(new GridLayoutManager(getActivity(),1));
if you have adapter to set. So you can follow this. Just call the getContext
adapter = new Adapter(getContext(), myModelList);
If you have Toast to show, use same thing above
Toast.makeText(getContext(), "Error in "+e, Toast.LENGTH_SHORT).show();
Hope this will work.
HappyCoding
Using Pandas to pd.read_excel() for multiple worksheets of the same workbook
If:
- you want multiple, but not all, worksheets, and
- you want a single df as an output
Then, you can pass a list of worksheet names. Which you could populate manually:
import pandas as pd
path = "C:\\Path\\To\\Your\\Data\\"
file = "data.xlsx"
sheet_lst_wanted = ["01_SomeName","05_SomeName","12_SomeName"] # tab names from Excel
### import and compile data ###
# read all sheets from list into an ordered dictionary
dict_temp = pd.read_excel(path+file, sheet_name= sheet_lst_wanted)
# concatenate the ordered dict items into a dataframe
df = pd.concat(dict_temp, axis=0, ignore_index=True)
OR
A bit of automation is possible if your desired worksheets have a common naming convention that also allows you to differentiate from unwanted sheets:
# substitute following block for the sheet_lst_wanted line in above block
import xlrd
# string common to only worksheets you want
str_like = "SomeName"
### create list of sheet names in Excel file ###
xls = xlrd.open_workbook(path+file, on_demand=True)
sheet_lst = xls.sheet_names()
### create list of sheets meeting criteria ###
sheet_lst_wanted = []
for s in sheet_lst:
# note: following conditional statement based on my sheets ending with the string defined in sheet_like
if s[-len(str_like):] == str_like:
sheet_lst_wanted.append(s)
else:
pass
How to define static constant in a class in swift
Some might want certain class constants public while others private.
private keyword can be used to limit the scope of constants within the same swift file.
class MyClass {
struct Constants {
static let testStr = "test"
static let testStrLen = testStr.characters.count
//testInt will not be accessable by other classes in different swift files
private static let testInt = 1
}
func ownFunction()
{
var newInt = Constants.testInt + 1
print("Print testStr=\(Constants.testStr)")
}
}
Other classes will be able to access your class constants like below
class MyClass2
{
func accessOtherConstants()
{
print("MyClass's testStr=\(MyClass.Constants.testStr)")
}
}
Why doesn't RecyclerView have onItemClickListener()?
This worked for me:
@Override
public void onBindViewHolder(PlacesListViewAdapter.ViewHolder holder, int position) {
----
----
----
// Set setOnClickListener(holder);
}
@Override
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
----
----
----
@Override
public void onClick(View view) {
// Use to get the item clicked getAdapterPosition()
}
}
SSL Error: unable to get local issuer certificate
If you are a linux user
Update node to a later version by running
sudo apt update
sudo apt install build-essential checkinstall libssl-dev
curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.35.1/install.sh | bash
nvm --version
nvm ls
nvm ls-remote
nvm install [version.number]
this should solve your problem
Disable Logback in SpringBoot
Same problem for me.
If you are using log4j2
In the Spring boot 2.4.0
I resolve below,
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
<exclusions>
<exclusion>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-log4j2</artifactId>
<exclusions>
<exclusion>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-slf4j-impl</artifactId> <-- exclude this artifactId
</exclusion>
</exclusions>
</dependency>
After, Maven Build > Clean > Run
Work for me.
Radio Buttons ng-checked with ng-model
I think you should only use ng-model and should work well for you, here is the link to the official documentation of angular https://docs.angularjs.org/api/ng/input/input%5Bradio%5D
The code from the example should not be difficult to adapt to your specific situation:
<script>
function Ctrl($scope) {
$scope.color = 'blue';
$scope.specialValue = {
"id": "12345",
"value": "green"
};
}
</script>
<form name="myForm" ng-controller="Ctrl">
<input type="radio" ng-model="color" value="red"> Red <br/>
<input type="radio" ng-model="color" ng-value="specialValue"> Green <br/>
<input type="radio" ng-model="color" value="blue"> Blue <br/>
<tt>color = {{color | json}}</tt><br/>
</form>
Generate 'n' unique random numbers within a range
Generate the range of data first and then shuffle it like this
import random
data = range(numLow, numHigh)
random.shuffle(data)
print data
By doing this way, you will get all the numbers in the particular range but in a random order.
But you can use random.sample
to get the number of elements you need, from a range of numbers like this
print random.sample(range(numLow, numHigh), 3)
Left Join without duplicate rows from left table
You can do this using generic SQL with group by
:
SELECT C.Content_ID, C.Content_Title, MAX(M.Media_Id)
FROM tbl_Contents C LEFT JOIN
tbl_Media M
ON M.Content_Id = C.Content_Id
GROUP BY C.Content_ID, C.Content_Title
ORDER BY MAX(C.Content_DatePublished) ASC;
Or with a correlated subquery:
SELECT C.Content_ID, C.Contt_Title,
(SELECT M.Media_Id
FROM tbl_Media M
WHERE M.Content_Id = C.Content_Id
ORDER BY M.MEDIA_ID DESC
LIMIT 1
) as Media_Id
FROM tbl_Contents C
ORDER BY C.Content_DatePublished ASC;
Of course, the syntax for limit 1
varies between databases. Could be top
. Or rownum = 1
. Or fetch first 1 rows
. Or something like that.
In Angular, how to pass JSON object/array into directive?
If you want to follow all the "best practices," there's a few things I'd recommend, some of which are touched on in other answers and comments to this question.
First, while it doesn't have too much of an affect on the specific question you asked, you did mention efficiency, and the best way to handle shared data in your application is to factor it out into a service.
I would personally recommend embracing AngularJS's promise system, which will make your asynchronous services more composable compared to raw callbacks. Luckily, Angular's $http
service already uses them under the hood. Here's a service that will return a promise that resolves to the data from the JSON file; calling the service more than once will not cause a second HTTP request.
app.factory('locations', function($http) {
var promise = null;
return function() {
if (promise) {
// If we've already asked for this data once,
// return the promise that already exists.
return promise;
} else {
promise = $http.get('locations/locations.json');
return promise;
}
};
});
As far as getting the data into your directive, it's important to remember that directives are designed to abstract generic DOM manipulation; you should not inject them with application-specific services. In this case, it would be tempting to simply inject the locations
service into the directive, but this couples the directive to that service.
A brief aside on code modularity: a directive’s functions should almost never be responsible for getting or formatting their own data. There’s nothing to stop you from using the $http service from within a directive, but this is almost always the wrong thing to do. Writing a controller to use $http is the right way to do it. A directive already touches a DOM element, which is a very complex object and is difficult to stub out for testing. Adding network I/O to the mix makes your code that much more difficult to understand and that much more difficult to test. In addition, network I/O locks in the way that your directive will get its data – maybe in some other place you’ll want to have this directive receive data from a socket or take in preloaded data. Your directive should either take data in as an attribute through scope.$eval and/or have a controller to handle acquiring and storing the data.
- The 80/20 Guide to Writing AngularJS Directives
In this specific case, you should place the appropriate data on your controller's scope and share it with the directive via an attribute.
app.controller('SomeController', function($scope, locations) {
locations().success(function(data) {
$scope.locations = data;
});
});
<ul class="list">
<li ng-repeat="location in locations">
<a href="#">{{location.id}}. {{location.name}}</a>
</li>
</ul>
<map locations='locations'></map>
app.directive('map', function() {
return {
restrict: 'E',
replace: true,
template: '<div></div>',
scope: {
// creates a scope variable in your directive
// called `locations` bound to whatever was passed
// in via the `locations` attribute in the DOM
locations: '=locations'
},
link: function(scope, element, attrs) {
scope.$watch('locations', function(locations) {
angular.forEach(locations, function(location, key) {
// do something
});
});
}
};
});
In this way, the map
directive can be used with any set of location data--the directive is not hard-coded to use a specific set of data, and simply linking the directive by including it in the DOM will not fire off random HTTP requests.
Android Animation Alpha
<ImageView
android:id="@+id/listViewIcon"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/settings"/>
Remove android:alpha=0.2
from XML-> ImageView.
How do I install PHP cURL on Linux Debian?
Type in console as root:
apt-get update && apt-get install php5-curl
or with sudo:
sudo apt-get update && sudo apt-get install php5-curl
Sorry I missread.
1st, check your DNS config and if you can ping any host at all,
ping google.com
ping zm.archive.ubuntu.com
If it does not work, check /etc/resolv.conf
or /etc/network/resolv.conf
, if not, change your apt-source to a different one.
/etc/apt/sources.list
Mirrors: http://www.debian.org/mirror/list
You should not use Ubuntu sources on Debian and vice versa.
Scanf/Printf double variable C
For variable argument functions like printf
and scanf
, the arguments are promoted, for example, any smaller integer types are promoted to int
, float
is promoted to double
.
scanf
takes parameters of pointers, so the promotion rule takes no effect. It must use %f
for float*
and %lf
for double*
.
printf
will never see a float
argument, float
is always promoted to double
. The format specifier is %f
. But C99 also says %lf
is the same as %f
in printf
:
C99 §7.19.6.1 The fprintf
function
l
(ell) Specifies that a following d
, i
, o
, u
, x
, or X
conversion specifier applies to a long int
or unsigned long int
argument; that a following n
conversion specifier applies to a pointer to a long int
argument; that a following c
conversion specifier applies to a wint_t
argument; that a following s
conversion specifier applies to a pointer to a wchar_t
argument; or has no effect on a following a
, A
, e
, E
, f
, F
, g
, or G
conversion specifier.
Icons missing in jQuery UI
Yeah I had the same problem and it was driving me crazy because I couldn't find the image.
This may help you out...
- Look for a CSS file in your directories called jquery-ui.css
- Open it up and search for ui-bg_flat_75_ffffff_40x100.png.
You will then see something like this...
.ui-widget-content {
border: 1px solid #aaaaaa;
background: #ffffff url(images/ui-bg_flat_75_ffffff_40x100.png) 50% 50% repeat-x;
color: #222222;
}
And comment out the background and save the CSS document. Or you can set an absolute path to that background property and see if that works for you. (i.e. background: #ffffff url(http://.../image.png
);
Hope this helps
extract part of a string using bash/cut/split
Using a single Awk:
... | awk -F '[/:]' '{print $5}'
That is, using as field separator either /
or :
, the username is always in field 5.
To store it in a variable:
username=$(... | awk -F '[/:]' '{print $5}')
A more flexible implementation with sed
that doesn't require username to be field 5:
... | sed -e s/:.*// -e s?.*/??
That is, delete everything from :
and beyond, and then delete everything up until the last /
. sed
is probably faster too than awk
, so this alternative is definitely better.
Add directives from directive in AngularJS
A simple solution that could work in some cases is to create and $compile a wrapper and then append your original element to it.
Something like...
link: function(scope, elem, attr){
var wrapper = angular.element('<div tooltip></div>');
elem.before(wrapper);
$compile(wrapper)(scope);
wrapper.append(elem);
}
This solution has the advantage that it keeps things simple by not recompiling the original element.
This wouldn't work if any of the added directive's require
any of the original element's directives or if the original element has absolute positioning.
mvn command is not recognized as an internal or external command
I also was facing with the same issue still after adding path in environment variable and running it as a normal user in command prompt.
Then I opened command prompt and tried running as "Run as Administrator" and I was able to download all the packages with respect to the project.
How to use Git Revert
Use git revert like so:
git revert <insert bad commit hash here>
git revert
creates a new commit with the changes that are rolled back. git reset
erases your git history instead of making a new commit.
The steps after are the same as any other commit.
How to delete a certain row from mysql table with same column values?
All tables should have a primary key (consisting of a single or multiple columns), duplicate rows doesn't make sense in a relational database. You can limit the number of delete rows using LIMIT
though:
DELETE FROM orders WHERE id_users = 1 AND id_product = 2 LIMIT 1
But that just solves your current issue, you should definitely work on the bigger issue by defining primary keys.
Java using scanner enter key pressed
This works using java.util.Scanner and will take multiple "enter" keystrokes:
Scanner scanner = new Scanner(System.in);
String readString = scanner.nextLine();
while(readString!=null) {
System.out.println(readString);
if (readString.isEmpty()) {
System.out.println("Read Enter Key.");
}
if (scanner.hasNextLine()) {
readString = scanner.nextLine();
} else {
readString = null;
}
}
To break it down:
Scanner scanner = new Scanner(System.in);
String readString = scanner.nextLine();
These lines initialize a new Scanner
that is reading from the standard input stream (the keyboard) and reads a single line from it.
while(readString!=null) {
System.out.println(readString);
While the scanner is still returning non-null data, print each line to the screen.
if (readString.isEmpty()) {
System.out.println("Read Enter Key.");
}
If the "enter" (or return, or whatever) key is supplied by the input, the nextLine()
method will return an empty string; by checking to see if the string is empty, we can determine whether that key was pressed. Here the text Read Enter Key is printed, but you could perform whatever action you want here.
if (scanner.hasNextLine()) {
readString = scanner.nextLine();
} else {
readString = null;
}
Finally, after printing the content and/or doing something when the "enter" key is pressed, we check to see if the scanner has another line; for the standard input stream, this method will "block" until either the stream is closed, the execution of the program ends, or further input is supplied.
Simplest way to do grouped barplot
Not a barplot
solution but using lattice
and barchart
:
library(lattice)
barchart(Species~Reason,data=Reasonstats,groups=Catergory,
scales=list(x=list(rot=90,cex=0.8)))
How to bind bootstrap popover on dynamic elements
This is how I made the code so it can handle dynamically created elements using popover feature. Using this code, you can trigger the popover to show by default.
HTML:
<div rel="this-should-be-the-target">
</div>
JQuery:
$(function() {
var targetElement = 'rel="this-should-be-the-target"';
initPopover(targetElement, "Test Popover Content");
// use this line if you want it to show by default
$(targetElement).popover('show');
function initPopover(target, popOverContent) {
$(target).each(function(i, obj) {
$(this).popover({
placement : 'auto',
trigger : 'hover',
"html": true,
content: popOverContent
});
});
}
});
Find duplicate values in R
This will give you duplicate rows:
vocabulary[duplicated(vocabulary$id),]
This will give you the number of duplicates:
dim(vocabulary[duplicated(vocabulary$id),])[1]
Example:
vocabulary2 <-rbind(vocabulary,vocabulary[1,]) #creates a duplicate at the end
vocabulary2[duplicated(vocabulary2$id),]
# id year sex education vocabulary
#21639 20040001 2004 Female 9 3
dim(vocabulary2[duplicated(vocabulary2$id),])[1]
#[1] 1 #=1 duplicate
EDIT
OK, with the additional information, here's what you should do: duplicated
has a fromLast
option which allows you to get duplicates from the end. If you combine this with the normal duplicated
, you get all duplicates. The following example adds duplicates to the original vocabulary object (line 1 is duplicated twice and line 5 is duplicated once). I then use table
to get the total number of duplicates per ID.
#Create vocabulary object with duplicates
voc.dups <-rbind(vocabulary,vocabulary[1,],vocabulary[1,],vocabulary[5,])
#List duplicates
dups <-voc.dups[duplicated(voc.dups$id)|duplicated(voc.dups$id, fromLast=TRUE),]
dups
# id year sex education vocabulary
#1 20040001 2004 Female 9 3
#5 20040008 2004 Male 14 1
#21639 20040001 2004 Female 9 3
#21640 20040001 2004 Female 9 3
#51000 20040008 2004 Male 14 1
#Count duplicates by id
table(dups$id)
#20040001 20040008
# 3 2
How to compare each item in a list with the rest, only once?
This code will count frequency and remove duplicate elements:
from collections import Counter
str1='the cat sat on the hat hat'
int_list=str1.split();
unique_list = []
for el in int_list:
if el not in unique_list:
unique_list.append(el)
else:
print "Element already in the list"
print unique_list
c=Counter(int_list)
c.values()
c.keys()
print c
jquery change button color onclick
$('input[type="submit"]').click(function(){
$(this).css('color','red');
});
Use class, Demo:- http://jsfiddle.net/BX6Df/
$('input[type="submit"]').click(function(){
$(this).addClass('red');
});
if you want to toggle the color each click, you can try this:- http://jsfiddle.net/SMNks/
$('input[type="submit"]').click(function(){
$(this).toggleClass('red');
});
.red
{
background-color:red;
}
Updated answer for your comment.
http://jsfiddle.net/H2Xhw/
$('input[type="submit"]').click(function(){
$('input[type="submit"].red').removeClass('red')
$(this).addClass('red');
});
Get the second largest number in a list in linear time
Since @OscarLopez and I have different opinions on what the second largest means, I'll post the code according to my interpretation and in line with the first algorithm provided by the questioner.
def second_largest(numbers):
count = 0
m1 = m2 = float('-inf')
for x in numbers:
count += 1
if x > m2:
if x >= m1:
m1, m2 = x, m1
else:
m2 = x
return m2 if count >= 2 else None
(Note: Negative infinity is used here instead of None
since None
has different sorting behavior in Python 2 and 3 – see Python - Find second smallest number; a check for the number of elements in numbers
makes sure that negative infinity won't be returned when the actual answer is undefined.)
If the maximum occurs multiple times, it may be the second largest as well. Another thing about this approach is that it works correctly if there are less than two elements; then there is no second largest.
Running the same tests:
second_largest([20,67,3,2.6,7,74,2.8,90.8,52.8,4,3,2,5,7])
=> 74
second_largest([1,1,1,1,1,2])
=> 1
second_largest([2,2,2,2,2,1])
=> 2
second_largest([10,7,10])
=> 10
second_largest([1,1,1,1,1,1])
=> 1
second_largest([1])
=> None
second_largest([])
=> None
Update
I restructured the conditionals to drastically improve performance; almost by a 100% in my testing on random numbers. The reason for this is that in the original version, the elif
was always evaluated in the likely event that the next number is not the largest in the list. In other words, for practically every number in the list, two comparisons were made, whereas one comparison mostly suffices – if the number is not larger than the second largest, it's not larger than the largest either.
Mocking python function based on input arguments
If you "want to return a fixed value when the input parameter has a particular value", maybe you don't even need a mock and could use a dict
along with its get
method:
foo = {'input1': 'value1', 'input2': 'value2'}.get
foo('input1') # value1
foo('input2') # value2
This works well when your fake's output is a mapping of input. When it's a function of input I'd suggest using side_effect
as per Amber's answer.
You can also use a combination of both if you want to preserve Mock
's capabilities (assert_called_once
, call_count
etc):
self.mock.side_effect = {'input1': 'value1', 'input2': 'value2'}.get
Why is it faster to check if dictionary contains the key, rather than catch the exception in case it doesn't?
Dictionaries are specifically designed to do super fast key lookups. They are implemented as hashtables and the more entries the faster they are relative to other methods. Using the exception engine is only supposed to be done when your method has failed to do what you designed it to do because it is a large set of object that give you a lot of functionality for handling errors. I built an entire library class once with everything surrounded by try catch blocks once and was appalled to see the debug output which contained a seperate line for every single one of over 600 exceptions!
If conditions in a Makefile, inside a target
There are several problems here, so I'll start with my usual high-level advice: Start small and simple, add complexity a little at a time, test at every step, and never add to code that doesn't work. (I really ought to have that hotkeyed.)
You're mixing Make syntax and shell syntax in a way that is just dizzying. You should never have let it get this big without testing. Let's start from the outside and work inward.
UNAME := $(shell uname -m)
all:
$(info Checking if custom header is needed)
ifeq ($(UNAME), x86_64)
... do some things to build unistd_32.h
endif
@make -C $(KDIR) M=$(PWD) modules
So you want unistd_32.h built (maybe) before you invoke the second make
, you can make it a prerequisite. And since you want that only in a certain case, you can put it in a conditional:
ifeq ($(UNAME), x86_64)
all: unistd_32.h
endif
all:
@make -C $(KDIR) M=$(PWD) modules
unistd_32.h:
... do some things to build unistd_32.h
Now for building unistd_32.h
:
F1_EXISTS=$(shell [ -e /usr/include/asm/unistd_32.h ] && echo 1 || echo 0 )
ifeq ($(F1_EXISTS), 1)
$(info Copying custom header)
$(shell sed -e 's/__NR_/__NR32_/g' /usr/include/asm/unistd_32.h > unistd_32.h)
else
F2_EXISTS=$(shell [[ -e /usr/include/asm-i386/unistd.h ]] && echo 1 || echo 0 )
ifeq ($(F2_EXISTS), 1)
$(info Copying custom header)
$(shell sed -e 's/__NR_/__NR32_/g' /usr/include/asm-i386/unistd.h > unistd_32.h)
else
$(error asm/unistd_32.h and asm-386/unistd.h does not exist)
endif
endif
You are trying to build unistd.h
from unistd_32.h
; the only trick is that unistd_32.h
could be in either of two places. The simplest way to clean this up is to use a vpath
directive:
vpath unistd.h /usr/include/asm /usr/include/asm-i386
unistd_32.h: unistd.h
sed -e 's/__NR_/__NR32_/g' $< > $@
PHP PDO with foreach and fetch
foreach over a statement is just a syntax sugar for the regular one-way fetch() loop. If you want to loop over your data more than once, select it as a regular array first
$sql = "SELECT * FROM users";
$stm = $dbh->query($sql);
// here you go:
$users = $stm->fetchAll();
foreach ($users as $row) {
print $row["name"] . "-" . $row["sex"] ."<br/>";
}
echo "<br/>";
foreach ($users as $row) {
print $row["name"] . "-" . $row["sex"] ."<br/>";
}
Also quit that try..catch
thing. Don't use it, but set the proper error reporting for PHP and PDO
How to correctly save instance state of Fragments in back stack?
This is the way I am using at this moment... it's very complicated but at least it handles all the possible situations. In case anyone is interested.
public final class MyFragment extends Fragment {
private TextView vstup;
private Bundle savedState = null;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.whatever, null);
vstup = (TextView)v.findViewById(R.id.whatever);
/* (...) */
/* If the Fragment was destroyed inbetween (screen rotation), we need to recover the savedState first */
/* However, if it was not, it stays in the instance from the last onDestroyView() and we don't want to overwrite it */
if(savedInstanceState != null && savedState == null) {
savedState = savedInstanceState.getBundle(App.STAV);
}
if(savedState != null) {
vstup.setText(savedState.getCharSequence(App.VSTUP));
}
savedState = null;
return v;
}
@Override
public void onDestroyView() {
super.onDestroyView();
savedState = saveState(); /* vstup defined here for sure */
vstup = null;
}
private Bundle saveState() { /* called either from onDestroyView() or onSaveInstanceState() */
Bundle state = new Bundle();
state.putCharSequence(App.VSTUP, vstup.getText());
return state;
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
/* If onDestroyView() is called first, we can use the previously savedState but we can't call saveState() anymore */
/* If onSaveInstanceState() is called first, we don't have savedState, so we need to call saveState() */
/* => (?:) operator inevitable! */
outState.putBundle(App.STAV, (savedState != null) ? savedState : saveState());
}
/* (...) */
}
Alternatively, it is always a possibility to keep the data displayed in passive View
s in variables and using the View
s only for displaying them, keeping the two things in sync. I don't consider the last part very clean, though.
jQuery click events firing multiple times
I had a problem because of markup.
HTML:
<div class="myclass">
<div class="inner">
<div class="myclass">
<a href="#">Click Me</a>
</div>
</div>
</div>
jQuery
$('.myclass').on('click', 'a', function(event) { ... } );
You notice I have the same class 'myclass' twice in html, so it calls click for each instance of div.
malloc for struct and pointer in C
No, you're not allocating memory for y->x
twice.
Instead, you're allocating memory for the structure (which includes a pointer) plus something for that pointer to point to.
Think of it this way:
1 2
+-----+ +------+
y------>| x------>| *x |
| n | +------+
+-----+
So you actually need the two allocations (1
and 2
) to store everything.
Additionally, your type should be struct Vector *y
since it's a pointer, and you should never cast the return value from malloc
in C since it can hide certain problems you don't want hidden - C is perfectly capable of implicitly converting the void*
return value to any other pointer.
And, of course, you probably want to encapsulate the creation of these vectors to make management of them easier, such as with:
struct Vector {
double *data; // no place for x and n in readable code :-)
size_t size;
};
struct Vector *newVector (size_t sz) {
// Try to allocate vector structure.
struct Vector *retVal = malloc (sizeof (struct Vector));
if (retVal == NULL)
return NULL;
// Try to allocate vector data, free structure if fail.
retVal->data = malloc (sz * sizeof (double));
if (retVal->data == NULL) {
free (retVal);
return NULL;
}
// Set size and return.
retVal->size = sz;
return retVal;
}
void delVector (struct Vector *vector) {
// Can safely assume vector is NULL or fully built.
if (vector != NULL) {
free (vector->data);
free (vector);
}
}
By encapsulating the creation like that, you ensure that vectors are either fully built or not built at all - there's no chance of them being half-built. It also allows you to totally change the underlying data structures in future without affecting clients (for example, if you wanted to make them sparse arrays to trade off space for speed).
Append text to textarea with javascript
Give this a try:
<!DOCTYPE html>
<html>
<head>
<title>List Test</title>
<style>
li:hover {
cursor: hand; cursor: pointer;
}
</style>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
<script>
$(document).ready(function(){
$("li").click(function(){
$('#alltext').append($(this).text());
});
});
</script>
</head>
<body>
<h2>List items</h2>
<ol>
<li>Hello</li>
<li>World</li>
<li>Earthlings</li>
</ol>
<form>
<textarea id="alltext"></textarea>
</form>
</body>
</html>
Open Popup window using javascript
Change the window name in your two different calls:
function popitup(url,windowName) {
newwindow=window.open(url,windowName,'height=200,width=150');
if (window.focus) {newwindow.focus()}
return false;
}
windowName must be unique when you open a new window with same url otherwise the same window will be refreshed.
SHA-256 or MD5 for file integrity
- Yes, on most CPUs, SHA-256 is two to three times slower than MD5, though not primarily because of its longer hash. See other answers here and the answers to this Stack Overflow questions.
- Here's a backup scenario where MD5 would not be appropriate:
- Your backup program hashes each file being backed up. It then stores
each file's data by its hash, so if you're backing up the same file
twice you only end up with one copy of it.
- An attacker can cause the system to backup files they control.
- The attacker knows the MD5 hash of a file they want to remove from the
backup.
- The attacker can then use the known weaknesses of MD5 to craft a new
file that has the same hash as the file to remove. When that file is
backed up, it will replace the file to remove, and that file's backed up
data will be lost.
- This backup system could be strengthened a bit (and made more efficient)
by not replacing files whose hash it has previously encountered, but
then an attacker could prevent a target file with a known hash from
being backed up by preemptively backing up a specially constructed bogus
file with the same hash.
- Obviously most systems, backup and otherwise, do not satisfy the
conditions necessary for this attack to be practical, but I just wanted
to give an example of a situation where SHA-256 would be preferable to
MD5. Whether this would be the case for the system you're creating
depends on more than just the characteristics of MD5 and SHA-256.
- Yes, cryptographic hashes like the ones generated by MD5 and SHA-256 are a type of checksum.
Happy hashing!
How do I delete all the duplicate records in a MySQL table without temp tables
An alternative way would be to create a new temporary table with same structure.
CREATE TABLE temp_table AS SELECT * FROM original_table LIMIT 0
Then create the primary key in the table.
ALTER TABLE temp_table ADD PRIMARY KEY (primary-key-field)
Finally copy all records from the original table while ignoring the duplicate records.
INSERT IGNORE INTO temp_table AS SELECT * FROM original_table
Now you can delete the original table and rename the new table.
DROP TABLE original_table
RENAME TABLE temp_table TO original_table
Java : Sort integer array without using Arrays.sort()
Array Sorting without using built in functions in java ......just make new File unsing this name -> (ArraySorting.java) ..... Run the Project and Enjoy it !!!!!
import java.io.*;
import java.util.Arrays;
import java.util.Scanner;
public class ArraySorting
{
public static void main(String args[])
{
int temp=0;
Scanner user_input=new Scanner(System.in);
System.out.println("enter Size of Array...");
int Size=user_input.nextInt();
int[] a=new int[Size];
System.out.println("Enter element Of an Array...");
for(int j=0;j<Size;j++)
{
a[j]=user_input.nextInt();
}
for(int index=0;index<a.length;index++)
{
for(int j=index+1;j<a.length;j++)
{
if(a[index] > a[j] )
{
temp = a[index];
a[index] = a[j];
a[j] = temp;
}
}
}
System.out.print("Output is:- ");
for(int i=0;i<a.length;i++)
{
System.out.println(a[i]);
}
}
}
How to do if-else in Thymeleaf?
In simpler case (when html tags is the same):
<h2 th:text="${potentially_complex_expression} ? 'Hello' : 'Something else'">/h2>
Read .csv file in C
A complete example which leaves the fields as NULL-terminated strings in the original input buffer and provides access to them via an array of char pointers. The CSV processor has been confirmed to work with fields enclosed in "double quotes", ignoring any delimiter chars within them.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
// adjust BUFFER_SIZE to suit longest line
#define BUFFER_SIZE 1024 * 1024
#define NUM_FIELDS 10
#define MAXERRS 5
#define RET_OK 0
#define RET_FAIL 1
#define FALSE 0
#define TRUE 1
// char* array will point to fields
char *pFields[NUM_FIELDS];
// field offsets into pFields array:
#define LP 0
#define IMIE 1
#define NAZWISKo 2
#define ULICA 3
#define NUMER 4
#define KOD 5
#define MIEJSCOw 6
#define TELEFON 7
#define EMAIL 8
#define DATA_UR 9
long loadFile(FILE *pFile, long *errcount);
static int loadValues(char *line, long lineno);
static char delim;
long loadFile(FILE *pFile, long *errcount){
char sInputBuf [BUFFER_SIZE];
long lineno = 0L;
if(pFile == NULL)
return RET_FAIL;
while (!feof(pFile)) {
// load line into static buffer
if(fgets(sInputBuf, BUFFER_SIZE-1, pFile)==NULL)
break;
// skip first line (headers)
if(++lineno==1)
continue;
// jump over empty lines
if(strlen(sInputBuf)==0)
continue;
// set pFields array pointers to null-terminated string fields in sInputBuf
if(loadValues(sInputBuf,lineno)==RET_FAIL){
(*errcount)++;
if(*errcount > MAXERRS)
break;
} else {
// On return pFields array pointers point to loaded fields ready for load into DB or whatever
// Fields can be accessed via pFields, e.g.
printf("lp=%s, imie=%s, data_ur=%s\n", pFields[LP], pFields[IMIE], pFields[DATA_UR]);
}
}
return lineno;
}
static int loadValues(char *line, long lineno){
if(line == NULL)
return RET_FAIL;
// chop of last char of input if it is a CR or LF (e.g.Windows file loading in Unix env.)
// can be removed if sure fgets has removed both CR and LF from end of line
if(*(line + strlen(line)-1) == '\r' || *(line + strlen(line)-1) == '\n')
*(line + strlen(line)-1) = '\0';
if(*(line + strlen(line)-1) == '\r' || *(line + strlen(line)-1 )== '\n')
*(line + strlen(line)-1) = '\0';
char *cptr = line;
int fld = 0;
int inquote = FALSE;
char ch;
pFields[fld]=cptr;
while((ch=*cptr) != '\0' && fld < NUM_FIELDS){
if(ch == '"') {
if(! inquote)
pFields[fld]=cptr+1;
else {
*cptr = '\0'; // zero out " and jump over it
}
inquote = ! inquote;
} else if(ch == delim && ! inquote){
*cptr = '\0'; // end of field, null terminate it
pFields[++fld]=cptr+1;
}
cptr++;
}
if(fld > NUM_FIELDS-1){
fprintf(stderr, "Expected field count (%d) exceeded on line %ld\n", NUM_FIELDS, lineno);
return RET_FAIL;
} else if (fld < NUM_FIELDS-1){
fprintf(stderr, "Expected field count (%d) not reached on line %ld\n", NUM_FIELDS, lineno);
return RET_FAIL;
}
return RET_OK;
}
int main(int argc, char **argv)
{
FILE *fp;
long errcount = 0L;
long lines = 0L;
if(argc!=3){
printf("Usage: %s csvfilepath delimiter\n", basename(argv[0]));
return (RET_FAIL);
}
if((delim=argv[2][0])=='\0'){
fprintf(stderr,"delimiter must be specified\n");
return (RET_FAIL);
}
fp = fopen(argv[1] , "r");
if(fp == NULL) {
fprintf(stderr,"Error opening file: %d\n",errno);
return(RET_FAIL);
}
lines=loadFile(fp,&errcount);
fclose(fp);
printf("Processed %ld lines, encountered %ld error(s)\n", lines, errcount);
if(errcount>0)
return(RET_FAIL);
return(RET_OK);
}
Visual Studio debugging/loading very slow
Another last resort solution with respect to time is to repair the VS installation.
- Go to
Tools
=> Get Tools and Features
- Locate the existing VS installation, and choose
repair
under the more button.
- For example: Visual Studio Enterprise 2019 installation.
How to detect iPhone 5 (widescreen devices)?
I found that answers do not include a special case for Simulators.
#define IS_WIDESCREEN ( [ [ UIScreen mainScreen ] bounds ].size.height == 568 )
#define IS_IPHONE ([[ [ UIDevice currentDevice ] model ] rangeOfString:@"iPhone"].location != NSNotFound)
#define IS_IPAD ([[ [ UIDevice currentDevice ] model ] rangeOfString:@"iPad"].location != NSNotFound)
#define IS_IPHONE_5 ( IS_IPHONE && IS_WIDESCREEN )
Python threading.timer - repeat function every 'n' seconds
This is an alternate implementation using function instead of class. Inspired by @Andrew Wilkins above.
Because wait is more accurate than sleep ( it takes function runtime into account ):
import threading
PING_ON = threading.Event()
def ping():
while not PING_ON.wait(1):
print("my thread %s" % str(threading.current_thread().ident))
t = threading.Thread(target=ping)
t.start()
sleep(5)
PING_ON.set()
Adding calculated column(s) to a dataframe in pandas
The first four functions you list will work on vectors as well, with the exception that lower_wick needs to be adapted. Something like this,
def lower_wick_vec(o, l, c):
min_oc = numpy.where(o > c, c, o)
return min_oc - l
where o, l and c are vectors.
You could do it this way instead which just takes the df as input and avoid using numpy, although it will be much slower:
def lower_wick_df(df):
min_oc = df[['Open', 'Close']].min(axis=1)
return min_oc - l
The other three will work on columns or vectors just as they are. Then you can finish off with
def is_hammer(df):
lw = lower_wick_at_least_twice_real_body(df["Open"], df["Low"], df["Close"])
cl = closed_in_top_half_of_range(df["High"], df["Low"], df["Close"])
return cl & lw
Bit operators can perform set logic on boolean vectors, &
for and
, |
for or
etc. This is enough to completely vectorize the sample calculations you gave and should be relatively fast. You could probably speed up even more by temporarily working with the numpy arrays underlying the data while performing these calculations.
For the second part, I would recommend introducing a column indicating the pattern for each row and writing a family of functions which deal with each pattern. Then groupby the pattern and apply the appropriate function to each group.
Thread Safe C# Singleton Pattern
Another version of Singleton where the following line of code creates the Singleton instance at the time of application startup.
private static readonly Singleton singleInstance = new Singleton();
Here CLR (Common Language Runtime) will take care of object initialization and thread safety. That means we will not require to write any code explicitly for handling the thread safety for a multithreaded environment.
"The Eager loading in singleton design pattern is nothing a process in
which we need to initialize the singleton object at the time of
application start-up rather than on demand and keep it ready in memory
to be used in future."
public sealed class Singleton
{
private static int counter = 0;
private Singleton()
{
counter++;
Console.WriteLine("Counter Value " + counter.ToString());
}
private static readonly Singleton singleInstance = new Singleton();
public static Singleton GetInstance
{
get
{
return singleInstance;
}
}
public void PrintDetails(string message)
{
Console.WriteLine(message);
}
}
from main :
static void Main(string[] args)
{
Parallel.Invoke(
() => PrintTeacherDetails(),
() => PrintStudentdetails()
);
Console.ReadLine();
}
private static void PrintTeacherDetails()
{
Singleton fromTeacher = Singleton.GetInstance;
fromTeacher.PrintDetails("From Teacher");
}
private static void PrintStudentdetails()
{
Singleton fromStudent = Singleton.GetInstance;
fromStudent.PrintDetails("From Student");
}
Android MediaPlayer Stop and Play
I may have not got your answer correct, but you can try this:
public void MusicController(View view) throws IOException{
switch (view.getId()){
case R.id.play: mplayer.start();break;
case R.id.pause: mplayer.pause(); break;
case R.id.stop:
if(mplayer.isPlaying()) {
mplayer.stop();
mplayer.prepare();
}
break;
}// where mplayer is defined in onCreate method}
as there is just one thread handling all, so stop() makes it die so we have to again prepare it If your intent is to start it again when your press start button(it throws IO Exception)
Or for better understanding of MediaPlayer you can refer to Android Media Player
What difference does .AsNoTracking() make?
Disabling tracking will also cause your result sets to be streamed into memory. This is more efficient when you're working with large sets of data and don't need the entire set of data all at once.
References:
Pointer to incomplete class type is not allowed
One thing to check for...
If your class is defined as a typedef:
typedef struct myclass { };
Then you try to refer to it as struct myclass
anywhere else, you'll get Incomplete Type errors left and right. It's sometimes a mistake to forget the class/struct was typedef'ed. If that's the case, remove "struct" from:
typedef struct mystruct {}...
struct mystruct *myvar = value;
Instead use...
mystruct *myvar = value;
Common mistake.
adding multiple event listeners to one element
What about something like this:
['focusout','keydown'].forEach( function(evt) {
self.slave.addEventListener(evt, function(event) {
// Here `this` is for the slave, i.e. `self.slave`
if ((event.type === 'keydown' && event.which === 27) || event.type === 'focusout') {
this.style.display = 'none';
this.parentNode.querySelector('.master').style.display = '';
this.parentNode.querySelector('.master').value = this.value;
console.log('out');
}
}, false);
});
// The above is replacement of:
/* self.slave.addEventListener("focusout", function(event) { })
self.slave.addEventListener("keydown", function(event) {
if (event.which === 27) { // Esc
}
})
*/
Programmatically change the src of an img tag
its ok now
function edit()
{
var inputs = document.myform;
for(var i = 0; i < inputs.length; i++) {
inputs[i].disabled = false;
}
var edit_save = document.getElementById("edit-save");
edit_save.src = "../template/save.png";
}
ldconfig error: is not a symbolic link
You need to include the path of the libraries inside /etc/ld.so.conf, and rerun ldconfig to upate the list
Other possibility is to include in the env variable LD_LIBRARY_PATH the path to your library, and rerun the executable.
check the symbolic links if they point to a valid library ...
You can add the path directly in /etc/ld.so.conf, without include...
run ldconfig -p
to see whether your library is well included in the cache.
Checking images for similarity with OpenCV
If for matching identical images ( same size/orientation )
// Compare two images by getting the L2 error (square-root of sum of squared error).
double getSimilarity( const Mat A, const Mat B ) {
if ( A.rows > 0 && A.rows == B.rows && A.cols > 0 && A.cols == B.cols ) {
// Calculate the L2 relative error between images.
double errorL2 = norm( A, B, CV_L2 );
// Convert to a reasonable scale, since L2 error is summed across all pixels of the image.
double similarity = errorL2 / (double)( A.rows * A.cols );
return similarity;
}
else {
//Images have a different size
return 100000000.0; // Return a bad value
}
Source
Losing scope when using ng-include
As @Renan mentioned, ng-include creates a new child scope. This scope prototypically inherits (see dashed lines below) from the HomeCtrl scope. ng-model="lineText"
actually creates a primitive scope property on the child scope, not HomeCtrl's scope. This child scope is not accessible to the parent/HomeCtrl scope:
To store what the user typed into HomeCtrl's $scope.lines array, I suggest you pass the value to the addLine function:
<form ng-submit="addLine(lineText)">
In addition, since lineText is owned by the ngInclude scope/partial, I feel it should be responsible for clearing it:
<form ng-submit="addLine(lineText); lineText=''">
Function addLine() would thus become:
$scope.addLine = function(lineText) {
$scope.chat.addLine(lineText);
$scope.lines.push({
text: lineText
});
};
Fiddle.
Alternatives:
- define an object property on HomeCtrl's $scope, and use that in the partial:
ng-model="someObj.lineText
; fiddle
- not recommended, this is more of a hack: use $parent in the partial to create/access a
lineText
property on the HomeCtrl $scope: ng-model="$parent.lineText"
; fiddle
It is a bit involved to explain why the above two alternatives work, but it is fully explained here: What are the nuances of scope prototypal / prototypical inheritance in AngularJS?
I don't recommend using this
in the addLine() function. It becomes much less clear which scope is being accessed/manipulated.
Reference alias (calculated in SELECT) in WHERE clause
It's actually possible to effectively define a variable that can be used in both the SELECT, WHERE and other clauses.
A cross join doesn't necessarily allow for appropriate binding to the referenced table columns, however OUTER APPLY does - and treats nulls more transparently.
SELECT
vars.BalanceDue
FROM
Entity e
OUTER APPLY (
SELECT
-- variables
BalanceDue = e.EntityTypeId,
Variable2 = ...some..long..complex..expression..etc...
) vars
WHERE
vars.BalanceDue > 0
Kudos to Syed Mehroz Alam.
Fragment onCreateView and onActivityCreated called twice
Ok, Here's what I found out.
What I didn't understand is that all fragments that are attached to an activity when a config change happens (phone rotates) are recreated and added back to the activity. (which makes sense)
What was happening in the TabListener constructor was the tab was detached if it was found and attached to the activity. See below:
mFragment = mActivity.getFragmentManager().findFragmentByTag(mTag);
if (mFragment != null && !mFragment.isDetached()) {
Log.d(TAG, "constructor: detaching fragment " + mTag);
FragmentTransaction ft = mActivity.getFragmentManager().beginTransaction();
ft.detach(mFragment);
ft.commit();
}
Later in the activity onCreate the previously selected tab was selected from the saved instance state. See below:
if (savedInstanceState != null) {
bar.setSelectedNavigationItem(savedInstanceState.getInt("tab", 0));
Log.d(TAG, "FragmentTabs.onCreate tab: " + savedInstanceState.getInt("tab"));
Log.d(TAG, "FragmentTabs.onCreate number: " + savedInstanceState.getInt("number"));
}
When the tab was selected it would be reattached in the onTabSelected callback.
public void onTabSelected(Tab tab, FragmentTransaction ft) {
if (mFragment == null) {
mFragment = Fragment.instantiate(mActivity, mClass.getName(), mArgs);
Log.d(TAG, "onTabSelected adding fragment " + mTag);
ft.add(android.R.id.content, mFragment, mTag);
} else {
Log.d(TAG, "onTabSelected attaching fragment " + mTag);
ft.attach(mFragment);
}
}
The fragment being attached is the second call to the onCreateView and onActivityCreated methods. (The first being when the system is recreating the acitivity and all attached fragments) The first time the onSavedInstanceState Bundle would have saved data but not the second time.
The solution is to not detach the fragment in the TabListener constructor, just leave it attached. (You still need to find it in the FragmentManager by it's tag) Also, in the onTabSelected method I check to see if the fragment is detached before I attach it. Something like this:
public void onTabSelected(Tab tab, FragmentTransaction ft) {
if (mFragment == null) {
mFragment = Fragment.instantiate(mActivity, mClass.getName(), mArgs);
Log.d(TAG, "onTabSelected adding fragment " + mTag);
ft.add(android.R.id.content, mFragment, mTag);
} else {
if(mFragment.isDetached()) {
Log.d(TAG, "onTabSelected attaching fragment " + mTag);
ft.attach(mFragment);
} else {
Log.d(TAG, "onTabSelected fragment already attached " + mTag);
}
}
}
Multiple queries executed in java in single statement
Why dont you try and write a Stored Procedure
for this?
You can get the Result Set
out and in the same Stored Procedure
you can Insert
what you want.
The only thing is you might not get the newly inserted rows in the Result Set
if you Insert
after the Select
.
How to control the width of select tag?
Add div wrapper
<div id=myForm>
<select name=countries>
<option value=af>Afghanistan</option>
<option value=ax>Åland Islands</option>
...
<option value=gs>South Georgia and the South Sandwich Islands</option>
...
</select>
</div>
and then write CSS
#myForm select {
width:200px; }
#myForm select:focus {
width:auto; }
Hope this will help.
RabbitMQ / AMQP: single queue, multiple consumers for same message?
Fan out was clearly what you wanted. fanout
read rabbitMQ tutorial:
https://www.rabbitmq.com/tutorials/tutorial-three-javascript.html
here's my example:
Publisher.js:
amqp.connect('amqp://<user>:<pass>@<host>:<port>', async (error0, connection) => {
if (error0) {
throw error0;
}
console.log('RabbitMQ connected')
try {
// Create exchange for queues
channel = await connection.createChannel()
await channel.assertExchange(process.env.EXCHANGE_NAME, 'fanout', { durable: false });
await channel.publish(process.env.EXCHANGE_NAME, '', Buffer.from('msg'))
} catch(error) {
console.error(error)
}
})
Subscriber.js:
amqp.connect('amqp://<user>:<pass>@<host>:<port>', async (error0, connection) => {
if (error0) {
throw error0;
}
console.log('RabbitMQ connected')
try {
// Create/Bind a consumer queue for an exchange broker
channel = await connection.createChannel()
await channel.assertExchange(process.env.EXCHANGE_NAME, 'fanout', { durable: false });
const queue = await channel.assertQueue('', {exclusive: true})
channel.bindQueue(queue.queue, process.env.EXCHANGE_NAME, '')
console.log(" [*] Waiting for messages in %s. To exit press CTRL+C");
channel.consume('', consumeMessage, {noAck: true});
} catch(error) {
console.error(error)
}
});
here is an example i found in the internet. maybe can also help.
https://www.codota.com/code/javascript/functions/amqplib/Channel/assertExchange
How to disable keypad popup when on edittext?
Thanks @A.B for good solution
android:focusableInTouchMode="false"
this case if you will disable keyboard in edit text , just add android:focusableInTouchMode="false" in edittext tagline.
work for me in Android Studio 3.0.1 minsdk 16 , maxsdk26
Facebook Graph API error code list
Facebook Developer Wiki (unofficial) contain not only list of FQL error codes but others too it's somehow updated but not contain full list of possible error codes.
There is no any official or updated (I mean really updated) list of error codes returned by Graph API. Every list that can be found online is outdated and not help that much...
There is official list describing some of API Errors and basic recovery tactics.
Also there is couple of offcial lists for specific codes:
How to transform currentTimeMillis to a readable date format?
There is a simpler way in Android
DateFormat.getInstance().format(currentTimeMillis);
Moreover, Date is deprecated, so use DateFormat class.
DateFormat.getDateInstance().format(new Date(0));
DateFormat.getDateTimeInstance().format(new Date(0));
DateFormat.getTimeInstance().format(new Date(0));
The above three lines will give:
Dec 31, 1969
Dec 31, 1969 4:00:00 PM
4:00:00 PM 12:00:00 AM
How can I generate a list or array of sequential integers in Java?
This is the shortest I could find.
List version
public List<Integer> makeSequence(int begin, int end)
{
List<Integer> ret = new ArrayList<Integer>(++end - begin);
for (; begin < end; )
ret.add(begin++);
return ret;
}
Array Version
public int[] makeSequence(int begin, int end)
{
if(end < begin)
return null;
int[] ret = new int[++end - begin];
for (int i=0; begin < end; )
ret[i++] = begin++;
return ret;
}
How do I bind Twitter Bootstrap tooltips to dynamically created elements?
For me, only catching the mouseenter event was a bit buggy, and the tooltip was not showing/hiding properly.
I had to write this, and it is now working perfectly:
$(document).on('mouseenter','[rel=tooltip]', function(){
$(this).tooltip('show');
});
$(document).on('mouseleave','[rel=tooltip]', function(){
$(this).tooltip('hide');
});
Read input stream twice
You can use org.apache.commons.io.IOUtils.copy
to copy the contents of the InputStream to a byte array, and then repeatedly read from the byte array using a ByteArrayInputStream. E.g.:
ByteArrayOutputStream baos = new ByteArrayOutputStream();
org.apache.commons.io.IOUtils.copy(in, baos);
byte[] bytes = baos.toByteArray();
// either
while (needToReadAgain) {
ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
yourReadMethodHere(bais);
}
// or
ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
while (needToReadAgain) {
bais.reset();
yourReadMethodHere(bais);
}
How do you split and unsplit a window/view in Eclipse IDE?
This is possible with the menu items Window>Editor>Toggle Split Editor.
Current shortcut for splitting is:
Azerty keyboard:
- Ctrl + _ for split horizontally, and
- Ctrl + { for split vertically.
Qwerty US keyboard:
- Ctrl + Shift + - (accessing _) for split horizontally, and
- Ctrl + Shift + [ (accessing {) for split vertically.
MacOS - Qwerty US keyboard:
- ⌘ + Shift + - (accessing _) for split horizontally, and
- ⌘ + Shift + [ (accessing {) for split vertically.
On any other keyboard if a required key is unavailable (like { on a german Qwertz keyboard), the following generic approach may work:
- Alt + ASCII code + Ctrl then release Alt
Example: ASCII for '{' = 123, so press 'Alt', '1', '2', '3', 'Ctrl' and release 'Alt', effectively typing '{' while 'Ctrl' is pressed, to split vertically.
Example of vertical split:
PS:
- The menu items Window>Editor>Toggle Split Editor were added with Eclipse Luna 4.4 M4, as mentioned by Lars Vogel in "Split editor implemented in Eclipse M4 Luna"
- The split editor is one of the oldest and most upvoted Eclipse bug! Bug 8009
- The split editor functionality has been developed in Bug 378298, and will be available as of Eclipse Luna M4. The Note & Newsworthy of Eclipse Luna M4 will contain the announcement.
ImportError: Cannot import name X
If you are importing file1.py
from file2.py
and used this:
if __name__ == '__main__':
# etc
Variables below that in file1.py
cannot be imported to file2.py
because __name__
does not equal __main__
!
If you want to import something from file1.py
to file2.py
, you need to use this in file1.py
:
if __name__ == 'file1':
# etc
In case of doubt, make an assert
statement to determine if __name__=='__main__'
How to beautify JSON in Python?
You could pipe the output to jq
. If you python script contains something like
print json.dumps(data)
then you can fire:
python foo.py | jq '.'
How do I call a function twice or more times consecutively?
Three more ways of doing so:
(I) I think using map
may also be an option, though is requires generation of an additional list with None
s in some cases and always needs a list of arguments:
def do():
print 'hello world'
l=map(lambda x: do(), range(10))
(II) itertools
contain functions which can be used used to iterate through other functions as well https://docs.python.org/2/library/itertools.html
(III) Using lists of functions was not mentioned so far I think (and it is actually the closest in syntax to the one originally discussed) :
it=[do]*10
[f() for f in it]
Or as a one liner:
[f() for f in [do]*10]
Syntax behind sorted(key=lambda: ...)
Another usage of lambda
and sorted
is like the following:
Given the input array: people = [[7,0],[4,4],[7,1],[5,0],[6,1],[5,2]]
The line: people_sort = sorted(people, key = lambda x: (-x[0], x[1]))
will give a people_sort
list as [[7,0],[7,1],[6,1],[5,0],[5,2],[4,4]]
In this case, key=lambda x: (-x[0], x[1])
basically tells sorted
to firstly sort the array based on the value of the first element of each of the instance(in descending order as the minus sign suggests), and then within the same subgroup, sort based on the second element of each of the instance(in ascending order as it is the default option).
Hope this is some useful information to you!
Android SeekBar setOnSeekBarChangeListener
Seekbar called onProgressChanged method when we initialize first time. We can skip by using below code
We need to check boolean it return false when initialize automatically
volumeManager.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int i, boolean b) {
if(b){
mAudioManager.setStreamVolume(AudioManager.STREAM_MUSIC, i, 0);
}
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
Clicking the back button twice to exit an activity
Back when Button pressed 2 times
public void click(View view){
if (isBackActivated) {
this.finish();
}
if (!isBackActivated) {
isBackActivated = true;
Toast.makeText(getApplicationContext(), "Again", Toast.LENGTH_SHORT).show();
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
@Override
public void run() {
isBackActivated = false; // setting isBackActivated after 2 second
}
}, 2000);
}
}
spring autowiring with unique beans: Spring expected single matching bean but found 2
If I'm not mistaken, the default bean name of a bean declared with @Component is the name of its class its first letter in lower-case. This means that
@Component
public class SuggestionService {
declares a bean of type SuggestionService
, and of name suggestionService
. It's equivalent to
@Component("suggestionService")
public class SuggestionService {
or to
<bean id="suggestionService" .../>
You're redefining another bean of the same type, but with a different name, in the XML:
<bean id="SuggestionService" class="com.hp.it.km.search.web.suggestion.SuggestionService">
...
</bean>
So, either specify the name of the bean in the annotation to be SuggestionService
, or use the ID suggestionService
in the XML (don't forget to also modify the <ref>
element, or to remove it, since it isn't needed). In this case, the XML definition will override the annotation definition.
Chaining multiple filter() in Django, is this a bug?
The way I understand it is that they are subtly different by design (and I am certainly open for correction): filter(A, B)
will first filter according to A and then subfilter according to B, while filter(A).filter(B)
will return a row that matches A 'and' a potentially different row that matches B.
Look at the example here:
https://docs.djangoproject.com/en/dev/topics/db/queries/#spanning-multi-valued-relationships
particularly:
Everything inside a single filter() call is applied simultaneously to filter out items matching all those requirements. Successive filter() calls further restrict the set of objects
...
In this second example (filter(A).filter(B)), the first filter restricted the queryset to (A). The second filter restricted the set of blogs further to those that are also (B). The entries select by the second filter may or may not be the same as the entries in the first filter.`
Powershell command to hide user from exchange address lists
You can use the following script, just replace DOMAIN with the name of your domain. When executed it will prompt you for a userlogin then hide that user's account from the address lists.
$name=Read-Host "Enter login name of user to hide"
Set-Mailbox -Identity DOMAIN\$name -HiddenFromAddressListsEnabled $true
Brian.
ORA-01008: not all variables bound. They are bound
I'd a similar problem in a legacy application, but de "--" was string parameter.
Ex.:
Dim cmd As New OracleCommand("INSERT INTO USER (name, address, photo) VALUES ('User1', '--', :photo)", oracleConnection)
Dim fs As IO.FileStream = New IO.FileStream("c:\img.jpg", IO.FileMode.Open)
Dim br As New IO.BinaryReader(fs)
cmd.Parameters.Add(New OracleParameter("photo", OracleDbType.Blob)).Value = br.ReadBytes(fs.Length)
cmd.ExecuteNonQuery() 'here throws ORA-01008
Changing address parameter value '--' to '00' or other thing, works.
fork() child and parent processes
This is the correct way for getting the correct output.... However, childs parent id maybe sometimes printed as 1 because parent process gets terminated and the root process with pid = 1 controls this orphan process.
pid_t pid;
pid = fork();
if (pid == 0)
printf("This is the child process. My pid is %d and my parent's id
is %d.\n", getpid(), getppid());
else
printf("This is the parent process. My pid is %d and my parent's
id is %d.\n", getpid(), pid);
geom_smooth() what are the methods available?
Sometimes it's asking the question that makes the answer jump out. The methods and extra arguments are listed on the ggplot2 wiki stat_smooth page.
Which is alluded to on the geom_smooth()
page with:
"See stat_smooth for examples of using built in model fitting if you
need some more flexible, this example shows you how to plot the fits
from any model of your choosing".
It's not the first time I've seen arguments in examples for ggplot graphs that aren't specifically in the function. It does make it tough to work out the scope of each function, or maybe I am yet to stumble upon a magic explicit list that says what will and will not work within each function.
Efficient iteration with index in Scala
I have the following approaches
object HelloV2 {
def main(args: Array[String]) {
//Efficient iteration with index in Scala
//Approach #1
var msg = "";
for (i <- args.indices)
{
msg+=(args(i));
}
var msg1="";
//Approach #2
for (i <- 0 until args.length)
{
msg1 += (args(i));
}
//Approach #3
var msg3=""
args.foreach{
arg =>
msg3 += (arg)
}
println("msg= " + msg);
println("msg1= " + msg1);
println("msg3= " + msg3);
}
}
Pythonic way to find maximum value and its index in a list?
I made some big lists. One is a list and one is a numpy array.
import numpy as np
import random
arrayv=np.random.randint(0,10,(100000000,1))
listv=[]
for i in range(0,100000000):
listv.append(random.randint(0,9))
Using jupyter notebook's %%time function I can compare the speed of various things.
2 seconds:
%%time
listv.index(max(listv))
54.6 seconds:
%%time
listv.index(max(arrayv))
6.71 seconds:
%%time
np.argmax(listv)
103 ms:
%%time
np.argmax(arrayv)
numpy's arrays are crazy fast.
Using HttpClient and HttpPost in Android with post parameters
You can actually send it as JSON the following way:
// Build the JSON object to pass parameters
JSONObject jsonObj = new JSONObject();
jsonObj.put("username", username);
jsonObj.put("apikey", apikey);
// Create the POST object and add the parameters
HttpPost httpPost = new HttpPost(url);
StringEntity entity = new StringEntity(jsonObj.toString(), HTTP.UTF_8);
entity.setContentType("application/json");
httpPost.setEntity(entity);
HttpClient client = new DefaultHttpClient();
HttpResponse response = client.execute(httpPost);
Can Mockito capture arguments of a method called multiple times?
I think it should be
verify(mockBar, times(2)).doSomething(...)
Sample from mockito javadoc:
ArgumentCaptor<Person> peopleCaptor = ArgumentCaptor.forClass(Person.class);
verify(mock, times(2)).doSomething(peopleCaptor.capture());
List<Person> capturedPeople = peopleCaptor.getAllValues();
assertEquals("John", capturedPeople.get(0).getName());
assertEquals("Jane", capturedPeople.get(1).getName());
"git rebase origin" vs."git rebase origin/master"
Here's a better option:
git remote set-head -a origin
From the documentation:
With -a, the remote is queried to determine its HEAD, then $GIT_DIR/remotes//HEAD is set to the same branch. e.g., if the remote HEAD is pointed at next, "git remote set-head origin -a" will set $GIT_DIR/refs/remotes/origin/HEAD to refs/remotes/origin/next. This will only work if refs/remotes/origin/next already exists; if not it must be fetched first.
This has actually been around quite a while (since v1.6.3); not sure how I missed it!
How to properly express JPQL "join fetch" with "where" clause as JPA 2 CriteriaQuery?
I will show visually the problem, using the great example from James answer and adding the alternative solution.
When you do the follow query, without the FETCH
:
Select e from Employee e
join e.phones p
where p.areaCode = '613'
You will have the follow results from Employee
as you expected:
EmployeeId |
EmployeeName |
PhoneId |
PhoneAreaCode |
1 |
James |
5 |
613 |
1 |
James |
6 |
416 |
But when you add the FETCH
word on JOIN
, this is what happens:
EmployeeId |
EmployeeName |
PhoneId |
PhoneAreaCode |
1 |
James |
5 |
613 |
The generated SQL is the same for the two queries, but the Hibernate removes on memory the 416
register when you use WHERE
on the FETCH
join.
So, to bring all phones and apply the WHERE
correctly, you need to have two JOIN
s: one for the WHERE
and another for the FETCH
. Like:
Select e from Employee e
join e.phones p
join fetch e.phones //no alias, to not commit the mistake
where p.areaCode = '613'
Is this the right way to clean-up Fragment back stack when leaving a deeply nested stack?
The other clean solution if you don't want to pop all stack entries...
getSupportFragmentManager().popBackStack(null, FragmentManager.POP_BACK_STACK_INCLUSIVE);
getSupportFragmentManager().beginTransaction().replace(R.id.home_activity_container, fragmentInstance).addToBackStack(null).commit();
This will clean the stack first and then load a new fragment, so at any given point you'll have only single fragment in stack
jQuery iframe load() event?
If possible, you'd be better off handling the load
event within the iframe's document and calling out to a function in the containing document. This has the advantage of working in all browsers and only running once.
In the main document:
function iframeLoaded() {
alert("Iframe loaded!");
}
In the iframe document:
window.onload = function() {
parent.iframeLoaded();
}
Maven – Always download sources and javadocs
In my case the "settings.xml" solution didn't work so I use this command in order to download all the sources:
mvn dependency:sources
You also can use it with other maven commands, for example:
mvn clean install dependency:sources -Dmaven.test.skip=true
To download all documentation, use the following command:
mvn dependency:resolve -Dclassifier=javadoc
jQuery $(".class").click(); - multiple elements, click event once
Apologies for bumping this old thread. I had the same problem right now, and I wanted to share my solution.
$(".yourButtonClass").on('click', function(event){
event.stopPropagation();
event.stopImmediatePropagation();
//(... rest of your JS code)
});
event.StopPropagation
and event.StopImmediatePropagation()
should do the trick.
Having a .class selector for Event handler will result in bubbling
of click event (sometimes to Parent element, sometimes to Children elements in DOM).
event.StopPropagation()
method ensures that event doesn't bubble to Parent elements, while event.StopImmediatePropagation()
method ensures that event doesn't bubble to Children elements of desired class selector.
Sources:
https://api.jquery.com/event.stoppropagation/
https://api.jquery.com/event.stopimmediatepropagation/
jQuery - Check if DOM element already exists
(()=> {
var elem = document.querySelector('.elem');
(
(elem) ?
console.log(elem+' was found.') :
console.log('not found')
)
})();
If it exists, it spits out the specified element as a DOM object. With JQuery $('.elem')
it only tells you that it's an object if found but not which.
for each inside a for each - Java
So you really want:
for each tweet
unless tweet is in db
insert tweet
If so, just write it down in your programming language.
Hint: The loop over the array is to be done before the insert, which is done depending on the outcome.
What you want to test is that all array elements are not equal to the current one. But your for loop does not do that.
How to implement a lock in JavaScript
I've had success mutex-promise.
I agree with other answers that you might not need locking in your case. But it's not true that one never needs locking in Javascript. You need mutual exclusivity when accessing external resources that do not handle concurrency.
LINQ to SQL: Multiple joins ON multiple Columns. Is this possible?
U can also use :
var query =
from t1 in myTABLE1List
join t2 in myTABLE1List
on new { ColA=t1.ColumnA, ColB=t1.ColumnB } equals new { ColA=t2.ColumnA, ColB=t2.ColumnB }
join t3 in myTABLE1List
on new {ColC=t2.ColumnA, ColD=t2.ColumnB } equals new { ColC=t3.ColumnA, ColD=t3.ColumnB }
what does this mean ? image/png;base64?
It's an inlined image (png), encoded in base64. It can make a page faster: the browser doesn't have to query the server for the image data separately, saving a round trip.
(It can also make it slower if abused: these resources are not cached, so the bytes are included in each page load.)
How to implement the factory method pattern in C++ correctly
Simple Factory Example:
// Factory returns object and ownership
// Caller responsible for deletion.
#include <memory>
class FactoryReleaseOwnership{
public:
std::unique_ptr<Foo> createFooInSomeWay(){
return std::unique_ptr<Foo>(new Foo(some, args));
}
};
// Factory retains object ownership
// Thus returning a reference.
#include <boost/ptr_container/ptr_vector.hpp>
class FactoryRetainOwnership{
boost::ptr_vector<Foo> myFoo;
public:
Foo& createFooInSomeWay(){
// Must take care that factory last longer than all references.
// Could make myFoo static so it last as long as the application.
myFoo.push_back(new Foo(some, args));
return myFoo.back();
}
};
Jquery split function
Try this. It uses the split
function which is a core part of javascript, nothing to do with jQuery.
var parts = html.split(":-"),
i, l
;
for (i = 0, l = parts.length; i < l; i += 2) {
$("#" + parts[i]).text(parts[i + 1]);
}
How to retrieve raw post data from HttpServletRequest in java
We had a situation where IE forced us to post as text/plain, so we had to manually parse the parameters using getReader. The servlet was being used for long polling, so when AsyncContext::dispatch was executed after a delay, it was literally reposting the request empty handed.
So I just stored the post in the request when it first appeared by using HttpServletRequest::setAttribute. The getReader method empties the buffer, where getParameter empties the buffer too but stores the parameters automagically.
String input = null;
// we have to store the string, which can only be read one time, because when the
// servlet awakens an AsyncContext, it reposts the request and returns here empty handed
if ((input = (String) request.getAttribute("com.xp.input")) == null) {
StringBuilder buffer = new StringBuilder();
BufferedReader reader = request.getReader();
String line;
while((line = reader.readLine()) != null){
buffer.append(line);
}
// reqBytes = buffer.toString().getBytes();
input = buffer.toString();
request.setAttribute("com.xp.input", input);
}
if (input == null) {
response.setContentType("text/plain");
PrintWriter out = response.getWriter();
out.print("{\"act\":\"fail\",\"msg\":\"invalid\"}");
}
Reliable way for a Bash script to get the full path to itself
Get the absolute path of a shell script
It does not use the -f
option in readlink, and it should therefore work on BSD/Mac OS X.
Supports
- source ./script (When called by the
.
dot operator)
- Absolute path /path/to/script
- Relative path like ./script
- /path/dir1/../dir2/dir3/../script
- When called from symlink
- When symlink is nested eg)
foo->dir1/dir2/bar bar->./../doe doe->script
- When caller changes the scripts name
I am looking for corner cases where this code does not work. Please let me know.
Code
pushd . > /dev/null
SCRIPT_PATH="${BASH_SOURCE[0]}";
while([ -h "${SCRIPT_PATH}" ]); do
cd "`dirname "${SCRIPT_PATH}"`"
SCRIPT_PATH="$(readlink "`basename "${SCRIPT_PATH}"`")";
done
cd "`dirname "${SCRIPT_PATH}"`" > /dev/null
SCRIPT_PATH="`pwd`";
popd > /dev/null
echo "srcipt=[${SCRIPT_PATH}]"
echo "pwd =[`pwd`]"
Known issus
The script must be on disk somewhere. Let it be over a network. If you try to run this script from a PIPE it will not work
wget -o /dev/null -O - http://host.domain/dir/script.sh |bash
Technically speaking, it is undefined. Practically speaking, there is no sane way to detect this. (A co-process can not access the environment of the parent.)
How can I run a PHP script in the background after a form is submitted?
Of all the answers, none considered the ridiculously easy fastcgi_finish_request function, that when called, flushes all remaining output to the browser and closes the Fastcgi session and the HTTP connection, while letting the script run in the background.
An example:
<?php
header('Content-Type: application/json');
echo json_encode(['ok' => true]);
fastcgi_finish_request(); // The user is now disconnected from the script
// do stuff with received data,
Adding/removing items from a JavaScript object with jQuery
If you are using jQuery you can use the extend function to add new items.
var olddata = {"fruit":{"apples":10,"pears":21}};
var newdata = {};
newdata['vegetables'] = {"carrots": 2, "potatoes" : 5};
$.extend(true, olddata, newdata);
This will generate:
{"fruit":{"apples":10,"pears":21}, "vegetables":{"carrots":2,"potatoes":5}};
Find duplicate entries in a column
Using:
SELECT t.ctn_no
FROM YOUR_TABLE t
GROUP BY t.ctn_no
HAVING COUNT(t.ctn_no) > 1
...will show you the ctn_no
value(s) that have duplicates in your table. Adding criteria to the WHERE will allow you to further tune what duplicates there are:
SELECT t.ctn_no
FROM YOUR_TABLE t
WHERE t.s_ind = 'Y'
GROUP BY t.ctn_no
HAVING COUNT(t.ctn_no) > 1
If you want to see the other column values associated with the duplicate, you'll want to use a self join:
SELECT x.*
FROM YOUR_TABLE x
JOIN (SELECT t.ctn_no
FROM YOUR_TABLE t
GROUP BY t.ctn_no
HAVING COUNT(t.ctn_no) > 1) y ON y.ctn_no = x.ctn_no
What's the best way to join on the same table twice?
The first method is the proper approach and will do what you need. However, with the inner joins, you will only select rows from Table1
if both phone numbers exist in Table2
. You may want to do a LEFT JOIN
so that all rows from Table1
are selected. If the phone numbers don't match, then the SomeOtherField
s would be null. If you want to make sure you have at least one matching phone number you could then do WHERE t2.PhoneNumber IS NOT NULL OR t3.PhoneNumber IS NOT NULL
The second method could have a problem: what happens if Table2
has both PhoneNumber1
and PhoneNumber2
? Which row will be selected? Depending on your data, foreign keys, etc. this may or may not be a problem.
Number of regex matches
I know this is a little old, but this but here is a concise function for counting regex patterns.
def regex_cnt(string, pattern):
return len(re.findall(pattern, string))
string = 'abc123'
regex_cnt(string, '[0-9]')
CodeIgniter 404 Page Not Found, but why?
It happens cause of multiple reasons but the answer missing above there's the "className" while extending your controller.
Make sure your class name is the same as your controller name is your controllers. e.g.,
If your controller name is Settings.php, you must extend the controller like.
class Settings extends CI_Controller
{
// some actions like...
public function __construct(){
// and so and so...
}
}
Peak detection in a 2D array
Physicist's solution:
Define 5 paw-markers identified by their positions X_i
and init them with random positions.
Define some energy function combining some award for location of markers in paws' positions with some punishment for overlap of markers; let's say:
E(X_i;S)=-Sum_i(S(X_i))+alfa*Sum_ij (|X_i-Xj|<=2*sqrt(2)?1:0)
(S(X_i)
is the mean force in 2x2 square around X_i
, alfa
is a parameter to be peaked experimentally)
Now time to do some Metropolis-Hastings magic:
1. Select random marker and move it by one pixel in random direction.
2. Calculate dE, the difference of energy this move caused.
3. Get an uniform random number from 0-1 and call it r.
4. If dE<0
or exp(-beta*dE)>r
, accept the move and go to 1; if not, undo the move and go to 1.
This should be repeated until the markers will converge to paws. Beta controls the scanning to optimizing tradeoff, so it should be also optimized experimentally; it can be also constantly increased with the time of simulation (simulated annealing).
Faster way to zero memory than with memset?
Nowadays your compiler should do all the work for you. At least of what I know gcc is very efficient in optimizing calls to memset
away (better check the assembler, though).
Then also, avoid memset
if you don't have to:
- use calloc for heap memory
- use proper initialization (
... = { 0
}
) for stack memory
And for really large chunks use mmap
if you have it. This just gets zero initialized memory from the system "for free".
JPA Criteria API - How to add JOIN clause (as general sentence as possible)
Actually you don't have to deal with the static metamodel if you had your annotations right.
With the following entities :
@Entity
public class Pet {
@Id
protected Long id;
protected String name;
protected String color;
@ManyToOne
protected Set<Owner> owners;
}
@Entity
public class Owner {
@Id
protected Long id;
protected String name;
}
You can use this :
CriteriaQuery<Pet> cq = cb.createQuery(Pet.class);
Metamodel m = em.getMetamodel();
EntityType<Pet> petMetaModel = m.entity(Pet.class);
Root<Pet> pet = cq.from(Pet.class);
Join<Pet, Owner> owner = pet.join(petMetaModel.getSet("owners", Owner.class));
append multiple values for one key in a dictionary
d = {}
# import list of year,value pairs
for year,value in mylist:
try:
d[year].append(value)
except KeyError:
d[year] = [value]
The Python way - it is easier to receive forgiveness than ask permission!
error: Unable to find vcvarsall.bat
calling import setuptools
will monkey patch distutils to force compatibility with Visual Studio. Calling vcvars32.bat
manually will setup the virtual environment and prevent other common errors the compiler will throw. For VS 2017 the file is located at
"C:\Program Files (x86)\Microsoft Visual
Studio\2017\Community\VC\Auxiliary\Build\vcvars32.bat"
Here is the setup script I use to quickly compile .pyx files to .pyd:
(Note: it uses the 3rd party module
send2trash
# cython_setup.py
import sys, os, time, platform, subprocess
from setuptools import setup, find_packages
from Cython.Build import cythonize
from traceback import format_exc
# USAGE:
#
# from cython_setup import run
# run(pyx_path)
# vcvars = r"C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Auxiliary\Build\vcvars32.bat"
# NOTE: to use visual studio 2017 you must have setuptools version 34+
vcvars = r"C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Auxiliary\Build\vcvars32.bat"
def _build_ext():
try:
pyx_path = sys.argv.pop(-1)
pyx_path = os.path.abspath(pyx_path)
if not os.path.exists(pyx_path):
raise FileNotFoundError(f"{pyx_path} does not exist")
project_name = sys.argv.pop(-1)
os.chdir(os.path.abspath(os.path.dirname(pyx_path)))
print("cwd: %s" % os.getcwd())
print(os.path.abspath("build"))
setup(
name=project_name,
# cmdclass = {'build_ext': build_ext},
packages=find_packages(),
# ext_modules=cythonize(extensions)
ext_modules=cythonize(pyx_path,
compiler_directives={'language_level': 3, 'infer_types': True, 'binding': False},
annotate=True),
# include_dirs = [numpy.get_include()]
build_dir=os.path.abspath("build")
)
except:
input(format_exc())
def retry(func):
def wrapper(*args, **kw):
tries = 0
while True:
try:
return func(*args, **kw)
except Exception:
tries += 1
if tries > 4:
raise
time.sleep(0.4)
return wrapper
@retry
def cleanup(pyx_path):
from send2trash import send2trash
c_file = os.path.splitext(pyx_path)[0] + ".c"
if os.path.exists(c_file):
os.remove(c_file)
if os.path.exists("build"):
send2trash("build")
def move_pyd_files(pyx_path):
pyx_dir = os.path.dirname(pyx_path)
build_dir = os.path.join(pyx_dir, "build")
if not os.path.exists(build_dir):
raise RuntimeError(f"build_dir {build_dir} did not exist....")
found_pyd = False
for top, dirs, nondirs in os.walk(build_dir):
for name in nondirs:
if name.lower().endswith(".pyd") or name.lower().endswith(".so"):
found_pyd = True
old_path = os.path.join(top, name)
new_path = os.path.join(pyx_dir, name)
if os.path.exists(new_path):
print(f"removing {new_path}")
os.remove(new_path)
print(f"file created at {new_path}")
os.rename(old_path, new_path)
if not found_pyd:
raise RuntimeError("Never found .pyd file to move")
def run(pyx_path):
"""
:param pyx_path:
:type pyx_path:
:return: this function creates the batch file, which in turn calls this module, which calls cythonize, once done
the batch script deletes itself... I'm sure theres a less convoluted way of doing this, but it works
:rtype:
"""
try:
project_name = os.path.splitext(os.path.basename(pyx_path))[0]
run_script(project_name, os.path.abspath(pyx_path))
except:
input(format_exc())
def run_script(project_name, pyx_path):
dirname = os.path.dirname(pyx_path)
# ------------------------------
os.chdir(dirname)
if os.path.exists(vcvars):
# raise RuntimeError(
# f"Could not find vcvars32.bat at {vcvars}\nis Visual Studio Installed?\nIs setuptools version > 34?")
subprocess.check_call(f'call "{vcvars}"', shell=True)
cmd = "python" if platform.system() == "Windows" else "python3"
subprocess.check_call(f'{cmd} "{__file__}" build_ext "{project_name}" "{pyx_path}"', shell=True)
move_pyd_files(pyx_path)
cleanup(pyx_path)
if len(sys.argv) > 2:
_build_ext()
Printing a 2D array in C
First you need to input the two numbers say num_rows and num_columns perhaps using argc and argv then do a for loop to print the dots.
int j=0;
int k=0;
for (k=0;k<num_columns;k++){
for (j=0;j<num_rows;j++){
printf(".");
}
printf("\n");
}
you'd have to replace the dot with something else later.
How to resolve Error listenerStart when deploying web-app in Tomcat 5.5?
Answered provided by Tom Saleeba is very helpful.
Today I also struggled with the same error
Apr 28, 2015 7:53:27 PM org.apache.catalina.core.StandardContext startInternal
SEVERE: Error listenerStart
I followed the suggestion and added the logging.properties file. And below was my reason of failure:
java.lang.IllegalStateException: Cannot set web app root system
property when WAR file is not expanded
The root cause of the issue was a listener (Log4jConfigListener) that I added into the web.xml. And as per the link SEVERE: Exception org.springframework.web.util.Log4jConfigListener , this listener cannot be added within a WAR that is not expanded.
It may be helpful for someone to know that this was happening on OpenShift JBoss gear.
How do I reset the scale/zoom of a web app on an orientation change on the iPhone?
Elisabeth you can change viewport content dynamically by adding the "id" property to the metatag:
<meta name="viewport" id="view" content="user-scalable=yes, width=device-width minimum-scale=1, maximum-scale=1" />
Then you just can call by javascript:
document.getElementById("view").setAttribute('content','user-scalable=yes, width=device-width, minimum-scale=1, maximum-scale=10');
How to delete an object by id with entity framework
dwkd's answer mostly worked for me in Entity Framework core, except when I saw this exception:
InvalidOperationException: The instance of entity type 'Customer' cannot
be tracked because another instance with the same key value for {'Id'}
is already being tracked. When attaching existing entities, ensure
that only one entity instance with a given key value is attached.
Consider using 'DbContextOptionsBuilder.EnableSensitiveDataLogging' to
see the conflicting key values.
To avoid the exception, I updated the code:
Customer customer = context.Customers.Local.First(c => c.Id == id);
if (customer == null) {
customer = new Customer () { Id = id };
context.Customers.Attach(customer);
}
context.Customers.Remove(customer);
context.SaveChanges();
How can I switch to a tag/branch in hg?
Once you have cloned the repo, you have everything: you can then hg up branchname
or hg up tagname
to update your working copy.
UP: hg up
is a shortcut of hg update
, which also has hg checkout
alias for people with git
habits.
How can I SELECT multiple columns within a CASE WHEN on SQL Server?
Actually you can do it.
Although, someone should note that repeating the CASE
statements are not bad as it seems. SQL Server's query optimizer is smart enough to not execute the CASE
twice so that you won't get any performance hit because of that.
Additionally, someone might use the following logic to not repeat the CASE (if it suits you..)
INSERT INTO dbo.T1
(
Col1,
Col2,
Col3
)
SELECT
1,
SUBSTRING(MyCase.MergedColumns, 0, CHARINDEX('%', MyCase.MergedColumns)),
SUBSTRING(MyCase.MergedColumns, CHARINDEX('%', MyCase.MergedColumns) + 1, LEN(MyCase.MergedColumns) - CHARINDEX('%', MyCase.MergedColumns))
FROM
dbo.T1 t
LEFT OUTER JOIN
(
SELECT CASE WHEN 1 = 1 THEN '2%3' END MergedColumns
) AS MyCase ON 1 = 1
This will insert the values (1, 2, 3) for each record in the table T1
. This uses a delimiter '%'
to split the merged columns. You can write your own split function depending on your needs (e.g. for handling null records or using complex delimiter for varchar
fields etc.). But the main logic is that you should join the CASE
statement and select from the result set of the join with using a split logic.
A select query selecting a select statement
Not sure if Access supports it, but in most engines (including SQL Server
) this is called a correlated subquery and works fine:
SELECT TypesAndBread.Type, TypesAndBread.TBName,
(
SELECT Count(Sandwiches.[SandwichID]) As SandwichCount
FROM Sandwiches
WHERE (Type = 'Sandwich Type' AND Sandwiches.Type = TypesAndBread.TBName)
OR (Type = 'Bread' AND Sandwiches.Bread = TypesAndBread.TBName)
) As SandwichCount
FROM TypesAndBread
This can be made more efficient by indexing Type
and Bread
and distributing the subqueries over the UNION
:
SELECT [Sandwiches Types].[Sandwich Type] As TBName, "Sandwich Type" As Type,
(
SELECT COUNT(*) As SandwichCount
FROM Sandwiches
WHERE Sandwiches.Type = [Sandwiches Types].[Sandwich Type]
)
FROM [Sandwiches Types]
UNION ALL
SELECT [Breads].[Bread] As TBName, "Bread" As Type,
(
SELECT COUNT(*) As SandwichCount
FROM Sandwiches
WHERE Sandwiches.Bread = [Breads].[Bread]
)
FROM [Breads]
FileSystemWatcher Changed event is raised twice
Here is my solution which helped me to stop the event being raised twice:
watcher.NotifyFilter = NotifyFilters.FileName | NotifyFilters.Size;
Here I have set the NotifyFilter
property with only Filename and size.
watcher
is my object of FileSystemWatcher. Hope this will help.
Generating a drop down list of timezones with PHP
$timezone = array(
'Pacific/Midway' => '(GMT-11:00) Midway Island, Samoa',
'America/Adak' => '(GMT-10:00) Hawaii-Aleutian',
'Etc/GMT+10' => '(GMT-10:00) Hawaii',
'Pacific/Marquesas' => '(GMT-09:30) Marquesas Islands',
'Pacific/Gambier' => '(GMT-09:00) Gambier Islands',
'America/Anchorage' => '(GMT-09:00) Alaska',
'America/Ensenada' => '(GMT-08:00) Tijuana, Baja California',
'Etc/GMT+8' => '(GMT-08:00) Pitcairn Islands',
'America/Los_Angeles' => '(GMT-08:00) Pacific Time (US & Canada)',
'America/Denver' => '(GMT-07:00) Mountain Time (US & Canada)',
'America/Chihuahua' => '(GMT-07:00) Chihuahua, La Paz, Mazatlan',
'America/Dawson_Creek' => '(GMT-07:00) Arizona',
'America/Belize' => '(GMT-06:00) Saskatchewan, Central America',
'America/Cancun' => '(GMT-06:00) Guadalajara, Mexico City, Monterrey',
'Chile/EasterIsland' => '(GMT-06:00) Easter Island',
'America/Chicago' => '(GMT-06:00) Central Time (US & Canada)',
'America/New_York' => '(GMT-05:00) Eastern Time (US & Canada)',
'America/Havana' => '(GMT-05:00) Cuba',
'America/Bogota' => '(GMT-05:00) Bogota, Lima, Quito, Rio Branco',
'America/Caracas' => '(GMT-04:30) Caracas',
'America/Santiago' => '(GMT-04:00) Santiago',
'America/La_Paz' => '(GMT-04:00) La Paz',
'Atlantic/Stanley' => '(GMT-04:00) Faukland Islands',
'America/Campo_Grande' => '(GMT-04:00) Brazil',
'America/Goose_Bay' => '(GMT-04:00) Atlantic Time (Goose Bay)',
'America/Glace_Bay' => '(GMT-04:00) Atlantic Time (Canada)',
'America/St_Johns' => '(GMT-03:30) Newfoundland',
'America/Araguaina' => '(GMT-03:00) UTC-3',
'America/Montevideo' => '(GMT-03:00) Montevideo',
'America/Miquelon' => '(GMT-03:00) Miquelon, St. Pierre',
'America/Godthab' => '(GMT-03:00) Greenland',
'America/Argentina/Buenos_Aires' => '(GMT-03:00) Buenos Aires',
'America/Sao_Paulo' => '(GMT-03:00) Brasilia',
'America/Noronha' => '(GMT-02:00) Mid-Atlantic',
'Atlantic/Cape_Verde' => '(GMT-01:00) Cape Verde Is.',
'Atlantic/Azores' => '(GMT-01:00) Azores',
'Europe/Belfast' => '(GMT) Greenwich Mean Time : Belfast',
'Europe/Dublin' => '(GMT) Greenwich Mean Time : Dublin',
'Europe/Lisbon' => '(GMT) Greenwich Mean Time : Lisbon',
'Europe/London' => '(GMT) Greenwich Mean Time : London',
'Africa/Abidjan' => '(GMT) Monrovia, Reykjavik',
'Europe/Amsterdam' => '(GMT+01:00) Amsterdam, Berlin, Bern, Rome, Stockholm, Vienna',
'Europe/Belgrade' => '(GMT+01:00) Belgrade, Bratislava, Budapest, Ljubljana, Prague',
'Europe/Brussels' => '(GMT+01:00) Brussels, Copenhagen, Madrid, Paris',
'Africa/Algiers' => '(GMT+01:00) West Central Africa',
'Africa/Windhoek' => '(GMT+01:00) Windhoek',
'Asia/Beirut' => '(GMT+02:00) Beirut',
'Africa/Cairo' => '(GMT+02:00) Cairo',
'Asia/Gaza' => '(GMT+02:00) Gaza',
'Africa/Blantyre' => '(GMT+02:00) Harare, Pretoria',
'Asia/Jerusalem' => '(GMT+02:00) Jerusalem',
'Europe/Minsk' => '(GMT+02:00) Minsk',
'Asia/Damascus' => '(GMT+02:00) Syria',
'Europe/Moscow' => '(GMT+03:00) Moscow, St. Petersburg, Volgograd',
'Africa/Addis_Ababa' => '(GMT+03:00) Nairobi',
'Asia/Tehran' => '(GMT+03:30) Tehran',
'Asia/Dubai' => '(GMT+04:00) Abu Dhabi, Muscat',
'Asia/Yerevan' => '(GMT+04:00) Yerevan',
'Asia/Kabul' => '(GMT+04:30) Kabul',
'Asia/Yekaterinburg' => '(GMT+05:00) Ekaterinburg',
'Asia/Tashkent' => '(GMT+05:00) Tashkent',
'Asia/Kolkata' => '(GMT+05:30) Chennai, Kolkata, Mumbai, New Delhi',
'Asia/Katmandu' => '(GMT+05:45) Kathmandu',
'Asia/Dhaka' => '(GMT+06:00) Astana, Dhaka',
'Asia/Novosibirsk' => '(GMT+06:00) Novosibirsk',
'Asia/Rangoon' => '(GMT+06:30) Yangon (Rangoon)',
'Asia/Bangkok' => '(GMT+07:00) Bangkok, Hanoi, Jakarta',
'Asia/Krasnoyarsk' => '(GMT+07:00) Krasnoyarsk',
'Asia/Hong_Kong' => '(GMT+08:00) Beijing, Chongqing, Hong Kong, Urumqi',
'Asia/Irkutsk' => '(GMT+08:00) Irkutsk, Ulaan Bataar',
'Australia/Perth' => '(GMT+08:00) Perth',
'Australia/Eucla' => '(GMT+08:45) Eucla',
'Asia/Tokyo' => '(GMT+09:00) Osaka, Sapporo, Tokyo',
'Asia/Seoul' => '(GMT+09:00) Seoul',
'Asia/Yakutsk' => '(GMT+09:00) Yakutsk',
'Australia/Adelaide' => '(GMT+09:30) Adelaide',
'Australia/Darwin' => '(GMT+09:30) Darwin',
'Australia/Brisbane' => '(GMT+10:00) Brisbane',
'Australia/Hobart' => '(GMT+10:00) Hobart',
'Asia/Vladivostok' => '(GMT+10:00) Vladivostok',
'Australia/Lord_Howe' => '(GMT+10:30) Lord Howe Island',
'Etc/GMT-11' => '(GMT+11:00) Solomon Is., New Caledonia',
'Asia/Magadan' => '(GMT+11:00) Magadan',
'Pacific/Norfolk' => '(GMT+11:30) Norfolk Island',
'Asia/Anadyr' => '(GMT+12:00) Anadyr, Kamchatka',
'Pacific/Auckland' => '(GMT+12:00) Auckland, Wellington',
'Etc/GMT-12' => '(GMT+12:00) Fiji, Kamchatka, Marshall Is.',
'Pacific/Chatham' => '(GMT+12:45) Chatham Islands',
'Pacific/Tongatapu' => '(GMT+13:00) Nukualofa',
'Pacific/Kiritimati' => '(GMT+14:00) Kiritimati',
date_default_timezone_set($timezone);
MySQL "CREATE TABLE IF NOT EXISTS" -> Error 1050
I had a similar Problem as @CraigWalker on debian: My database was in a state where a DROP TABLE
failed because it couldn't find the table, but a CREATE TABLE
also failed because MySQL thought the table still existed. So the broken table still existed somewhere although it wasn't there when I looked in phpmyadmin.
I created this state by just copying the whole folder that contained a database with some MyISAM
and some InnoDB
tables
cp -a /var/lib/mysql/sometable /var/lib/mysql/test
(this is not recommended!)
All InnoDB tables where not visible in the new database test
in phpmyadmin.
sudo mysqladmin flush-tables
didn't help either.
My solution: I had to delete the new test database with drop database test
and copy it with mysqldump
instead:
mysqldump somedatabase -u username -p -r export.sql
mysql test -u username -p < export.sql
How to hide Table Row Overflow?
Only downside (it seems), is that the
table cell widths are identical. Any
way to get around this? – Josh Stodola
Oct 12 at 15:53
Just define width of the table and width for each table cell
something like
table {border-collapse:collapse; table-layout:fixed; width:900px;}
th {background: yellow; }
td {overflow:hidden;white-space:nowrap; }
.cells1{width:300px;}
.cells2{width:500px;}
.cells3{width:200px;}
It works like a charm :o)
How can I get the name of an object in Python?
This one-liner works, for all types of objects, as long as they are in globals()
dict, which they should be:
def name_of_global_obj(xx):
return [objname for objname, oid in globals().items()
if id(oid)==id(xx)][0]
or, equivalently:
def name_of_global_obj(xx):
for objname, oid in globals().items():
if oid is xx:
return objname
Python Git Module experiences?
I thought I would answer my own question, since I'm taking a different path than suggested in the answers. Nonetheless, thanks to those who answered.
First, a brief synopsis of my experiences with GitPython, PyGit, and Dulwich:
- GitPython: After downloading, I got this imported and the appropriate object initialized. However, trying to do what was suggested in the tutorial led to errors. Lacking more documentation, I turned elsewhere.
- PyGit: This would not even import, and I could find no documentation.
- Dulwich: Seems to be the most promising (at least for what I wanted and saw). I made some progress with it, more than with GitPython, since its egg comes with Python source. However, after a while, I decided it may just be easier to try what I did.
Also, StGit looks interesting, but I would need the functionality extracted into a separate module and do not want wait for that to happen right now.
In (much) less time than I spent trying to get the three modules above working, I managed to get git commands working via the subprocess module, e.g.
def gitAdd(fileName, repoDir):
cmd = ['git', 'add', fileName]
p = subprocess.Popen(cmd, cwd=repoDir)
p.wait()
gitAdd('exampleFile.txt', '/usr/local/example_git_repo_dir')
This isn't fully incorporated into my program yet, but I'm not anticipating a problem, except maybe speed (since I'll be processing hundreds or even thousands of files at times).
Maybe I just didn't have the patience to get things going with Dulwich or GitPython. That said, I'm hopeful the modules will get more development and be more useful soon.
C++ Redefinition Header Files (winsock2.h)
#pragma once
is based on the full path of the filename. So what you likely have is there are two identical copies of either MyClass.h or Winsock2.h in different directories.
Add list to set?
You want to add a tuple, not a list:
>>> a=set('abcde')
>>> a
set(['a', 'c', 'b', 'e', 'd'])
>>> l=['f','g']
>>> l
['f', 'g']
>>> t = tuple(l)
>>> t
('f', 'g')
>>> a.add(t)
>>> a
set(['a', 'c', 'b', 'e', 'd', ('f', 'g')])
If you have a list, you can convert to the tuple, as shown above. A tuple is immutable, so it can be added to the set.
Disable pasting text into HTML form
You can disable the copy paste option with jQuery by the below script:
jQuery("input").attr("onpaste","return false;");
of by using the bellow oppaste attribute into the input fields.
onpaste="return false;"
How to efficiently calculate a running standard deviation?
The Python runstats Module is for just this sort of thing. Install runstats from PyPI:
pip install runstats
Runstats summaries can produce the mean, variance, standard deviation, skewness, and kurtosis in a single pass of data. We can use this to create your "running" version.
from runstats import Statistics
stats = [Statistics() for num in range(len(data[0]))]
for row in data:
for index, val in enumerate(row):
stats[index].push(val)
for index, stat in enumerate(stats):
print 'Index', index, 'mean:', stat.mean()
print 'Index', index, 'standard deviation:', stat.stddev()
Statistics summaries are based on the Knuth and Welford method for computing standard deviation in one pass as described in the Art of Computer Programming, Vol 2, p. 232, 3rd edition. The benefit of this is numerically stable and accurate results.
Disclaimer: I am the author the Python runstats module.
Random String Generator Returning Same String
I created this method.
It works great.
public static string GeneratePassword(int Lenght, int NonAlphaNumericChars)
{
string allowedChars = "abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNOPQRSTUVWXYZ0123456789";
string allowedNonAlphaNum = "!@#$%^&*()_-+=[{]};:<>|./?";
Random rd = new Random();
if (NonAlphaNumericChars > Lenght || Lenght <= 0 || NonAlphaNumericChars < 0)
throw new ArgumentOutOfRangeException();
char[] pass = new char[Lenght];
int[] pos = new int[Lenght];
int i = 0, j = 0, temp = 0;
bool flag = false;
//Random the position values of the pos array for the string Pass
while (i < Lenght - 1)
{
j = 0;
flag = false;
temp = rd.Next(0, Lenght);
for (j = 0; j < Lenght; j++)
if (temp == pos[j])
{
flag = true;
j = Lenght;
}
if (!flag)
{
pos[i] = temp;
i++;
}
}
//Random the AlphaNumericChars
for (i = 0; i < Lenght - NonAlphaNumericChars; i++)
pass[i] = allowedChars[rd.Next(0, allowedChars.Length)];
//Random the NonAlphaNumericChars
for (i = Lenght - NonAlphaNumericChars; i < Lenght; i++)
pass[i] = allowedNonAlphaNum[rd.Next(0, allowedNonAlphaNum.Length)];
//Set the sorted array values by the pos array for the rigth posistion
char[] sorted = new char[Lenght];
for (i = 0; i < Lenght; i++)
sorted[i] = pass[pos[i]];
string Pass = new String(sorted);
return Pass;
}
When do I need to use a semicolon vs a slash in Oracle SQL?
I know this is an old thread, but I just stumbled upon it and I feel this has not been explained completely.
There is a huge difference in SQL*Plus between the meaning of a /
and a ;
because they work differently.
The ;
ends a SQL statement, whereas the /
executes whatever is in the current "buffer". So when you use a ;
and a /
the statement is actually executed twice.
You can easily see that using a /
after running a statement:
SQL*Plus: Release 11.2.0.1.0 Production on Wed Apr 18 12:37:20 2012
Copyright (c) 1982, 2010, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning and OLAP options
SQL> drop table foo;
Table dropped.
SQL> /
drop table foo
*
ERROR at line 1:
ORA-00942: table or view does not exist
In this case one actually notices the error.
But assuming there is a SQL script like this:
drop table foo;
/
And this is run from within SQL*Plus then this will be very confusing:
SQL*Plus: Release 11.2.0.1.0 Production on Wed Apr 18 12:38:05 2012
Copyright (c) 1982, 2010, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning and OLAP options
SQL> @drop
Table dropped.
drop table foo
*
ERROR at line 1:
ORA-00942: table or view does not exist
The /
is mainly required in order to run statements that have embedded ;
like a CREATE PROCEDURE
statement.
Using DISTINCT and COUNT together in a MySQL Query
SELECTING DISTINCT PRODUCT AND DISPLAY COUNT PER PRODUCT
for another answer about this type of question this is my another answer for getting count of product base on product name distinct like this sample below:
Table Value
select * FROM Product
Counted Product Name
SELECT DISTINCT(Product_Name),
(SELECT COUNT(Product_Name)
from Product WHERE Product_Name = Prod.Product_Name)
as `Product_Count`
from Product as Prod
Record Count: 4; Execution Time: 2ms
Resolving ORA-4031 "unable to allocate x bytes of shared memory"
Don't forget about fragmentation.
If you have a lot of traffic, your pools can be fragmented and even if you have several MB free, there could be no block larger than 4KB.
Check size of largest free block with a query like:
select
'0 (<140)' BUCKET, KSMCHCLS, KSMCHIDX,
10*trunc(KSMCHSIZ/10) "From",
count(*) "Count" ,
max(KSMCHSIZ) "Biggest",
trunc(avg(KSMCHSIZ)) "AvgSize",
trunc(sum(KSMCHSIZ)) "Total"
from
x$ksmsp
where
KSMCHSIZ<140
and
KSMCHCLS='free'
group by
KSMCHCLS, KSMCHIDX, 10*trunc(KSMCHSIZ/10)
UNION ALL
select
'1 (140-267)' BUCKET,
KSMCHCLS,
KSMCHIDX,
20*trunc(KSMCHSIZ/20) ,
count(*) ,
max(KSMCHSIZ) ,
trunc(avg(KSMCHSIZ)) "AvgSize",
trunc(sum(KSMCHSIZ)) "Total"
from
x$ksmsp
where
KSMCHSIZ between 140 and 267
and
KSMCHCLS='free'
group by
KSMCHCLS, KSMCHIDX, 20*trunc(KSMCHSIZ/20)
UNION ALL
select
'2 (268-523)' BUCKET,
KSMCHCLS,
KSMCHIDX,
50*trunc(KSMCHSIZ/50) ,
count(*) ,
max(KSMCHSIZ) ,
trunc(avg(KSMCHSIZ)) "AvgSize",
trunc(sum(KSMCHSIZ)) "Total"
from
x$ksmsp
where
KSMCHSIZ between 268 and 523
and
KSMCHCLS='free'
group by
KSMCHCLS, KSMCHIDX, 50*trunc(KSMCHSIZ/50)
UNION ALL
select
'3-5 (524-4107)' BUCKET,
KSMCHCLS,
KSMCHIDX,
500*trunc(KSMCHSIZ/500) ,
count(*) ,
max(KSMCHSIZ) ,
trunc(avg(KSMCHSIZ)) "AvgSize",
trunc(sum(KSMCHSIZ)) "Total"
from
x$ksmsp
where
KSMCHSIZ between 524 and 4107
and
KSMCHCLS='free'
group by
KSMCHCLS, KSMCHIDX, 500*trunc(KSMCHSIZ/500)
UNION ALL
select
'6+ (4108+)' BUCKET,
KSMCHCLS,
KSMCHIDX,
1000*trunc(KSMCHSIZ/1000) ,
count(*) ,
max(KSMCHSIZ) ,
trunc(avg(KSMCHSIZ)) "AvgSize",
trunc(sum(KSMCHSIZ)) "Total"
from
x$ksmsp
where
KSMCHSIZ >= 4108
and
KSMCHCLS='free'
group by
KSMCHCLS, KSMCHIDX, 1000*trunc(KSMCHSIZ/1000);
Code from
Simple tool to 'accept theirs' or 'accept mine' on a whole file using git
Based on kynan's answer, here are the same aliases, modified so they can handle spaces and initial dashes in filenames:
accept-ours = "!f() { [ -z \"$@\" ] && set - '.'; git checkout --ours -- \"$@\"; git add -u -- \"$@\"; }; f"
accept-theirs = "!f() { [ -z \"$@\" ] && set - '.'; git checkout --theirs -- \"$@\"; git add -u -- \"$@\"; }; f"
Item frequency count in Python
The Counter
class in the collections
module is purpose built to solve this type of problem:
from collections import Counter
words = "apple banana apple strawberry banana lemon"
Counter(words.split())
# Counter({'apple': 2, 'banana': 2, 'strawberry': 1, 'lemon': 1})
adding child nodes in treeview
SqlConnection con = new SqlConnection(@"Data Source=NIKOLAY;Initial Catalog=PlanZadanie;Integrated Security=True");
SqlCommand cmd = new SqlCommand();
DataTable dt = new DataTable();
public void loadTree(TreeView tree)
{
cmd.Connection = con;
cmd.CommandType = CommandType.Text;
cmd.CommandText = "SELECT [RAZDEL_ID],[NAME_RAZDEL] FROM [tbl_RAZDEL]";
try
{
con.Open();
SqlDataReader reader = cmd.ExecuteReader();
while (reader.Read())
{
tree.Nodes.Add(reader.GetString(1));
tree.Nodes[0].Nodes.Add("yourChildNode");
tree.ExpandAll();
}
con.Close();
}
catch (Exception ex)
{
MessageBox.Show("?????? ? ??????????: " + ex.Message);
}
}
Globally catch exceptions in a WPF application?
Here is complete example using NLog
using NLog;
using System;
using System.Windows;
namespace MyApp
{
/// <summary>
/// Interaction logic for App.xaml
/// </summary>
public partial class App : Application
{
private static Logger logger = LogManager.GetCurrentClassLogger();
public App()
{
var currentDomain = AppDomain.CurrentDomain;
currentDomain.UnhandledException += CurrentDomain_UnhandledException;
}
private void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
{
var ex = (Exception)e.ExceptionObject;
logger.Error("UnhandledException caught : " + ex.Message);
logger.Error("UnhandledException StackTrace : " + ex.StackTrace);
logger.Fatal("Runtime terminating: {0}", e.IsTerminating);
}
}
}
Batch Renaming of Files in a Directory
Try: http://www.mattweber.org/2007/03/04/python-script-renamepy/
I like to have my music, movie, and
picture files named a certain way.
When I download files from the
internet, they usually don’t follow my
naming convention. I found myself
manually renaming each file to fit my
style. This got old realy fast, so I
decided to write a program to do it
for me.
This program can convert the filename
to all lowercase, replace strings in
the filename with whatever you want,
and trim any number of characters from
the front or back of the filename.
The program's source code is also available.
How do I scroll to an element within an overflowed Div?
After playing with it for a very long time, this is what I came up with:
jQuery.fn.scrollTo = function (elem) {
var b = $(elem);
this.scrollTop(b.position().top + b.height() - this.height());
};
and I call it like this
$("#basketListGridHolder").scrollTo('tr[data-uid="' + basketID + '"]');
How do I check if a variable is of a certain type (compare two types) in C?
From linux/typecheck.h:
/*
* Check at compile time that something is of a particular type.
* Always evaluates to 1 so you may use it easily in comparisons.
*/
#define typecheck(type,x) \
({ type __dummy; \
typeof(x) __dummy2; \
(void)(&__dummy == &__dummy2); \
1; \
})
Here you can find explanation which statements from standard and which GNU extensions above code uses.
(Maybe a bit not in scope of the question, since question is not about failure on type mismatch, but anyway, leaving it here).
PHP - Modify current object in foreach loop
There are 2 ways of doing this
foreach($questions as $key => $question){
$questions[$key]['answers'] = $answers_model->get_answers_by_question_id($question['question_id']);
}
This way you save the key, so you can update it again in the main $questions
variable
or
foreach($questions as &$question){
Adding the &
will keep the $questions
updated. But I would say the first one is recommended even though this is shorter (see comment by Paystey)
Per the PHP foreach
documentation:
In order to be able to directly modify array elements within the loop precede $value with &. In that case the value will be assigned by reference.
SQL where datetime column equals today's date?
Can you try this?
SELECT [Title], [Firstname], [Surname], [Company_name], [Interest]
FROM [dbo].[EXTRANET_users]
WHERE CAST(Submission_date AS DATE) = CAST(GETDATE() AS DATE)
T-SQL doesn't really have the "implied" casting like C# does - you need to explicitly use CAST
(or CONVERT
).
Also, use GETDATE()
or CURRENT_TIMESTAMP
to get the "now" date and time.
Update: since you're working against SQL Server 2000 - none of those approaches so far work. Try this instead:
SELECT [Title], [Firstname], [Surname], [Company_name], [Interest]
FROM [dbo].[EXTRANET_users]
WHERE DATEADD(dd, 0, DATEDIFF(dd, 0, submission_date)) = DATEADD(dd, 0, DATEDIFF(dd, 0, GETDATE()))
Guid.NewGuid() vs. new Guid()
new Guid()
makes an "empty" all-0 guid (00000000-0000-0000-0000-000000000000 is not very useful).
Guid.NewGuid()
makes an actual guid with a unique value, what you probably want.
How to generate Class Diagram (UML) on Android Studio (IntelliJ Idea)
Update 24.3.2016
I have found this guide from VP https://knowhow.visual-paradigm.com/technical-support/running-vp-in-android-studio/ created on September 8, 2015.
Good to know - it is possible to integrate VP into Android studio (in my case 1.5.1) now. Do not forget to backup your Android Studio settings (you can find them in Users%userName/.AndroidStudioX.X on Windows) ahead of installation.
I was trying to make it work, but created vp project did not contain any diagrams. Maybe someone else will have more luck.
I was using this manual http://www.visual-paradigm.com/support/documents/vpuserguide/2381/2385/66578_creatingauml.html to make Visual Paradigm working in Android studio, but action in 2. did not invoke dialogue in 3. So I Have asked Visual Paradigm support for help and they replied that Android Studio integration is not supported right now.
Reply from Visual paradigm reply from Apr 17 2015:
Thank you for your inquiry and I'm very sorry that at the moment we
only support integrate with the standard IntelliJ IDEA, but
not integrate with the Android Studio. We may consider to support it in our future release, and I'll keep you post once there
any update on this topics. Feel free to contact me for any questions
and wish you have a good day!
This post was deleted, so I will try to make it more clear.
As such I am considering previous answers as misleading and not useful. Therefore I thing that it is important for others to know that, before they lose their time trying to make it working.
Fetching data from MySQL database to html dropdown list
To do this you want to loop through each row of your query results and use this info for each of your drop down's options. You should be able to adjust the code below fairly easily to meet your needs.
// Assume $db is a PDO object
$query = $db->query("YOUR QUERY HERE"); // Run your query
echo '<select name="DROP DOWN NAME">'; // Open your drop down box
// Loop through the query results, outputing the options one by one
while ($row = $query->fetch(PDO::FETCH_ASSOC)) {
echo '<option value="'.$row['something'].'">'.$row['something'].'</option>';
}
echo '</select>';// Close your drop down box
Getting current unixtimestamp using Moment.js
For anyone who finds this page looking for unix timestamp w/ milliseconds, the documentation says
moment().valueOf()
or
+moment();
you can also get it through moment().format('x')
(or .format('X')
[capital X] for unix seconds with decimal milliseconds), but that will give you a string. Which moment.js won't actually parse back afterwards, unless you convert/cast it back to a number first.
Java: JSON -> Protobuf & back conversion
For protobuf 2.5, use the dependency:
"com.googlecode.protobuf-java-format" % "protobuf-java-format" % "1.2"
Then use the code:
com.googlecode.protobuf.format.JsonFormat.merge(json, builder)
com.googlecode.protobuf.format.JsonFormat.printToString(proto)
java.util.NoSuchElementException - Scanner reading user input
The problem is
When a Scanner is closed, it will close its input source if the source implements the Closeable interface.
http://docs.oracle.com/javase/1.5.0/docs/api/java/util/Scanner.html
Thus scan.close()
closes System.in
.
To fix it you can make
Scanner scan
static
and do not close it in PromptCustomerQty. Code below works.
public static void main (String[] args) {
// Create a customer
// Future proofing the possabiltiies of multiple customers
Customer customer = new Customer("Will");
// Create object for each Product
// (Name,Code,Description,Price)
// Initalize Qty at 0
Product Computer = new Product("Computer","PC1003","Basic Computer",399.99);
Product Monitor = new Product("Monitor","MN1003","LCD Monitor",99.99);
Product Printer = new Product("Printer","PR1003x","Inkjet Printer",54.23);
// Define internal variables
// ## DONT CHANGE
ArrayList<Product> ProductList = new ArrayList<Product>(); // List to store Products
String formatString = "%-15s %-10s %-20s %-10s %-10s %n"; // Default format for output
// Add objects to list
ProductList.add(Computer);
ProductList.add(Monitor);
ProductList.add(Printer);
// Ask users for quantities
PromptCustomerQty(customer, ProductList);
// Ask user for payment method
PromptCustomerPayment(customer);
// Create the header
PrintHeader(customer, formatString);
// Create Body
PrintBody(ProductList, formatString);
}
static Scanner scan;
public static void PromptCustomerQty(Customer customer, ArrayList<Product> ProductList) {
// Initiate a Scanner
scan = new Scanner(System.in);
// **** VARIABLES ****
int qty = 0;
// Greet Customer
System.out.println("Hello " + customer.getName());
// Loop through each item and ask for qty desired
for (Product p : ProductList) {
do {
// Ask user for qty
System.out.println("How many would you like for product: " + p.name);
System.out.print("> ");
// Get input and set qty for the object
qty = scan.nextInt();
}
while (qty < 0); // Validation
p.setQty(qty); // Set qty for object
qty = 0; // Reset count
}
// Cleanup
}
public static void PromptCustomerPayment (Customer customer) {
// Variables
String payment = "";
// Prompt User
do {
System.out.println("Would you like to pay in full? [Yes/No]");
System.out.print("> ");
payment = scan.next();
} while ((!payment.toLowerCase().equals("yes")) && (!payment.toLowerCase().equals("no")));
// Check/set result
if (payment.toLowerCase() == "yes") {
customer.setPaidInFull(true);
}
else {
customer.setPaidInFull(false);
}
}
On a side note, you shouldn't use ==
for String comparision, use .equals
instead.
What does T&& (double ampersand) mean in C++11?
It denotes an rvalue reference. Rvalue references will only bind to temporary objects, unless explicitly generated otherwise. They are used to make objects much more efficient under certain circumstances, and to provide a facility known as perfect forwarding, which greatly simplifies template code.
In C++03, you can't distinguish between a copy of a non-mutable lvalue and an rvalue.
std::string s;
std::string another(s); // calls std::string(const std::string&);
std::string more(std::string(s)); // calls std::string(const std::string&);
In C++0x, this is not the case.
std::string s;
std::string another(s); // calls std::string(const std::string&);
std::string more(std::string(s)); // calls std::string(std::string&&);
Consider the implementation behind these constructors. In the first case, the string has to perform a copy to retain value semantics, which involves a new heap allocation. However, in the second case, we know in advance that the object which was passed in to our constructor is immediately due for destruction, and it doesn't have to remain untouched. We can effectively just swap the internal pointers and not perform any copying at all in this scenario, which is substantially more efficient. Move semantics benefit any class which has expensive or prohibited copying of internally referenced resources. Consider the case of std::unique_ptr
- now that our class can distinguish between temporaries and non-temporaries, we can make the move semantics work correctly so that the unique_ptr
cannot be copied but can be moved, which means that std::unique_ptr
can be legally stored in Standard containers, sorted, etc, whereas C++03's std::auto_ptr
cannot.
Now we consider the other use of rvalue references- perfect forwarding. Consider the question of binding a reference to a reference.
std::string s;
std::string& ref = s;
(std::string&)& anotherref = ref; // usually expressed via template
Can't recall what C++03 says about this, but in C++0x, the resultant type when dealing with rvalue references is critical. An rvalue reference to a type T, where T is a reference type, becomes a reference of type T.
(std::string&)&& ref // ref is std::string&
(const std::string&)&& ref // ref is const std::string&
(std::string&&)&& ref // ref is std::string&&
(const std::string&&)&& ref // ref is const std::string&&
Consider the simplest template function- min and max. In C++03 you have to overload for all four combinations of const and non-const manually. In C++0x it's just one overload. Combined with variadic templates, this enables perfect forwarding.
template<typename A, typename B> auto min(A&& aref, B&& bref) {
// for example, if you pass a const std::string& as first argument,
// then A becomes const std::string& and by extension, aref becomes
// const std::string&, completely maintaining it's type information.
if (std::forward<A>(aref) < std::forward<B>(bref))
return std::forward<A>(aref);
else
return std::forward<B>(bref);
}
I left off the return type deduction, because I can't recall how it's done offhand, but that min can accept any combination of lvalues, rvalues, const lvalues.
How do I associate file types with an iPhone application?
BIG WARNING: Make ONE HUNDRED PERCENT sure that your extension is not already tied to some mime type.
We used the extension '.icz' for our custom files for, basically, ever, and Safari just never would let you open them saying "Safari cannot open this file." no matter what we did or tried with the UT stuff above.
Eventually I realized that there are some UT* C functions you can use to explore various things, and while .icz gives the right answer (our app):
In app did load at top, just do this...
NSString * UTI = (NSString *)UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension,
(CFStringRef)@"icz",
NULL);
CFURLRef ur =UTTypeCopyDeclaringBundleURL(UTI);
and put break after that line and see what UTI and ur are -- in our case, it was our identifier as we wanted), and the bundle url (ur) was pointing to our app's folder.
But the MIME type that Dropbox gives us back for our link, which you can check by doing e.g.
$ curl -D headers THEURLGOESHERE > /dev/null
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 27393 100 27393 0 0 24983 0 0:00:01 0:00:01 --:--:-- 28926
$ cat headers
HTTP/1.1 200 OK
accept-ranges: bytes
cache-control: max-age=0
content-disposition: attachment; filename="123.icz"
Content-Type: text/calendar
Date: Fri, 24 May 2013 17:41:28 GMT
etag: 872926d
pragma: public
Server: nginx
x-dropbox-request-id: 13bd327248d90fde
X-RequestId: bf9adc56934eff0bfb68a01d526eba1f
x-server-response-time: 379
Content-Length: 27393
Connection: keep-alive
The Content-Type is what we want. Dropbox claims this is a text/calendar entry. Great. But in my case, I've ALREADY TRIED PUTTING text/calendar into my app's mime types, and it still doesn't work. Instead, when I try to get the UTI and bundle url for the text/calendar mimetype,
NSString * UTI = (NSString *)UTTypeCreatePreferredIdentifierForTag(kUTTagClassMIMEType,
(CFStringRef)@"text/calendar",
NULL);
CFURLRef ur =UTTypeCopyDeclaringBundleURL(UTI);
I see "com.apple.ical.ics" as the UTI and ".../MobileCoreTypes.bundle/" as the bundle URL. Not our app, but Apple. So I try putting com.apple.ical.ics into the LSItemContentTypes alongside my own, and into UTConformsTo in the export, but no go.
So basically, if Apple thinks they want to at some point handle some form of file type (that could be created 10 years after your app is live, mind you), you will have to change extension cause they'll simply not let you handle the file type.
How to backup a local Git repository?
I started hacking away a bit on Yar's script and the result is on github, including man pages and install script:
https://github.com/najamelan/git-backup
Installation:
git clone "https://github.com/najamelan/git-backup.git"
cd git-backup
sudo ./install.sh
Welcoming all suggestions and pull request on github.
#!/usr/bin/env ruby
#
# For documentation please sea man git-backup(1)
#
# TODO:
# - make it a class rather than a function
# - check the standard format of git warnings to be conform
# - do better checking for git repo than calling git status
# - if multiple entries found in config file, specify which file
# - make it work with submodules
# - propose to make backup directory if it does not exists
# - depth feature in git config (eg. only keep 3 backups for a repo - like rotate...)
# - TESTING
# allow calling from other scripts
def git_backup
# constants:
git_dir_name = '.git' # just to avoid magic "strings"
filename_suffix = ".git.bundle" # will be added to the filename of the created backup
# Test if we are inside a git repo
`git status 2>&1`
if $?.exitstatus != 0
puts 'fatal: Not a git repository: .git or at least cannot get zero exit status from "git status"'
exit 2
else # git status success
until File::directory?( Dir.pwd + '/' + git_dir_name ) \
or File::directory?( Dir.pwd ) == '/'
Dir.chdir( '..' )
end
unless File::directory?( Dir.pwd + '/.git' )
raise( 'fatal: Directory still not a git repo: ' + Dir.pwd )
end
end
# git-config --get of version 1.7.10 does:
#
# if the key does not exist git config exits with 1
# if the key exists twice in the same file with 2
# if the key exists exactly once with 0
#
# if the key does not exist , an empty string is send to stdin
# if the key exists multiple times, the last value is send to stdin
# if exaclty one key is found once, it's value is send to stdin
#
# get the setting for the backup directory
# ----------------------------------------
directory = `git config --get backup.directory`
# git config adds a newline, so remove it
directory.chomp!
# check exit status of git config
case $?.exitstatus
when 1 : directory = Dir.pwd[ /(.+)\/[^\/]+/, 1]
puts 'Warning: Could not find backup.directory in your git config file. Please set it. See "man git config" for more details on git configuration files. Defaulting to the same directroy your git repo is in: ' + directory
when 2 : puts 'Warning: Multiple entries of backup.directory found in your git config file. Will use the last one: ' + directory
else unless $?.exitstatus == 0 then raise( 'fatal: unknown exit status from git-config: ' + $?.exitstatus ) end
end
# verify directory exists
unless File::directory?( directory )
raise( 'fatal: backup directory does not exists: ' + directory )
end
# The date and time prefix
# ------------------------
prefix = ''
prefix_date = Time.now.strftime( '%F' ) + ' - ' # %F = YYYY-MM-DD
prefix_time = Time.now.strftime( '%H:%M:%S' ) + ' - '
add_date_default = true
add_time_default = false
prefix += prefix_date if git_config_bool( 'backup.prefix-date', add_date_default )
prefix += prefix_time if git_config_bool( 'backup.prefix-time', add_time_default )
# default bundle name is the name of the repo
bundle_name = Dir.pwd.split('/').last
# set the name of the file to the first command line argument if given
bundle_name = ARGV[0] if( ARGV[0] )
bundle_name = File::join( directory, prefix + bundle_name + filename_suffix )
puts "Backing up to bundle #{bundle_name.inspect}"
# git bundle will print it's own error messages if it fails
`git bundle create #{bundle_name.inspect} --all --remotes`
end # def git_backup
# helper function to call git config to retrieve a boolean setting
def git_config_bool( option, default_value )
# get the setting for the prefix-time from git config
config_value = `git config --get #{option.inspect}`
# check exit status of git config
case $?.exitstatus
# when not set take default
when 1 : return default_value
when 0 : return true unless config_value =~ /(false|no|0)/i
when 2 : puts 'Warning: Multiple entries of #{option.inspect} found in your git config file. Will use the last one: ' + config_value
return true unless config_value =~ /(false|no|0)/i
else raise( 'fatal: unknown exit status from git-config: ' + $?.exitstatus )
end
end
# function needs to be called if we are not included in another script
git_backup if __FILE__ == $0
Python Socket Receive Large Amount of Data
Most of the answers describe some sort of recvall()
method. If your bottleneck when receiving data is creating the byte array in a for
loop, I benchmarked three approaches of allocating the received data in the recvall()
method:
Byte string method:
arr = b''
while len(arr) < msg_len:
arr += sock.recv(max_msg_size)
List method:
fragments = []
while True:
chunk = sock.recv(max_msg_size)
if not chunk:
break
fragments.append(chunk)
arr = b''.join(fragments)
Pre-allocated bytearray
method:
arr = bytearray(msg_len)
pos = 0
while pos < msg_len:
arr[pos:pos+max_msg_size] = sock.recv(max_msg_size)
pos += max_msg_size
Results:
Best Way to read rss feed in .net Using C#
Update: This supports only with UWP - Windows Community Toolkit
There is a much easier way now. You can use the RssParser class. The sample code is given below.
public async void ParseRSS()
{
string feed = null;
using (var client = new HttpClient())
{
try
{
feed = await client.GetStringAsync("https://visualstudiomagazine.com/rss-feeds/news.aspx");
}
catch { }
}
if (feed != null)
{
var parser = new RssParser();
var rss = parser.Parse(feed);
foreach (var element in rss)
{
Console.WriteLine($"Title: {element.Title}");
Console.WriteLine($"Summary: {element.Summary}");
}
}
}
For non-UWP use the Syndication from the namespace System.ServiceModel.Syndication
as others suggested.
public static IEnumerable <FeedItem> GetLatestFivePosts() {
var reader = XmlReader.Create("https://sibeeshpassion.com/feed/");
var feed = SyndicationFeed.Load(reader);
reader.Close();
return (from itm in feed.Items select new FeedItem {
Title = itm.Title.Text, Link = itm.Id
}).ToList().Take(5);
}
public class FeedItem {
public string Title {
get;
set;
}
public string Link {
get;
set;
}
}
client denied by server configuration
This has happened to me several times migrating from Apache 2.2.
What I have found is that there is an Order,Deny that I missed with VIM's Search feature somehow that is the default main Vhost, line 379. Hope this helps someone. I commented out the Order Deny,Allow and Deny from All and it worked!
MySQL ORDER BY multiple column ASC and DESC
Ok, I THINK I understand what you want now, and let me clarify to confirm before the query. You want 1 record for each user. For each user, you want their BEST POINTS score record. Of the best points per user, you want the one with the best average time. Once you have all users "best" values, you want the final results sorted with best points first... Almost like ranking of a competition.
So now the query. If the above statement is accurate, you need to start with getting the best point/average time per person and assigning a "Rank" to that entry. This is easily done using MySQL @ variables. Then, just include a HAVING clause to only keep those records ranked 1 for each person. Finally apply the order by of best points and shortest average time.
select
U.UserName,
PreSortedPerUser.Point,
PreSortedPerUser.Avg_Time,
@UserRank := if( @lastUserID = PreSortedPerUser.User_ID, @UserRank +1, 1 ) FinalRank,
@lastUserID := PreSortedPerUser.User_ID
from
( select
S.user_id,
S.point,
S.avg_time
from
Scores S
order by
S.user_id,
S.point DESC,
S.Avg_Time ) PreSortedPerUser
JOIN Users U
on PreSortedPerUser.user_ID = U.ID,
( select @lastUserID := 0,
@UserRank := 0 ) sqlvars
having
FinalRank = 1
order by
Point Desc,
Avg_Time
Results as handled by SQLFiddle
Note, due to the inline @variables needed to get the answer, there are the two extra columns at the end of each row. These are just "left-over" and can be ignored in any actual output presentation you are trying to do... OR, you can wrap the entire thing above one more level to just get the few columns you want like
select
PQ.UserName,
PQ.Point,
PQ.Avg_Time
from
( entire query above pasted here ) as PQ
Find and replace strings in vim on multiple lines
In vim if you are confused which all lines will be affected, Use below
:%s/foo/bar/gc
Change each 'foo' to 'bar', but ask for confirmation first.
Press 'y' for yes and 'n' for no. Dont forget to save after that
:wq
How to view the committed files you have not pushed yet?
git diff HEAD origin/master
Where origin
is the remote repository and master
is the default branch where you will push. Also, do a git fetch
before the diff
so that you are not diffing against a stale origin/master.
P.S. I am also new to git, so in case the above is wrong, please rectify.
Putting text in top left corner of matplotlib plot
You can use text
.
text(x, y, s, fontsize=12)
text
coordinates can be given relative to the axis, so the position of your text will be independent of the size of the plot:
The default transform specifies that text is in data coords,
alternatively, you can specify text in axis coords (0,0 is lower-left
and 1,1 is upper-right). The example below places text in the center
of the axes::
text(0.5, 0.5,'matplotlib',
horizontalalignment='center',
verticalalignment='center',
transform = ax.transAxes)
To prevent the text to interfere with any point of your scatter is more difficult afaik. The easier method is to set y_axis (ymax in ylim((ymin,ymax))
) to a value a bit higher than the max y-coordinate of your points. In this way you will always have this free space for the text.
EDIT: here you have an example:
In [17]: from pylab import figure, text, scatter, show
In [18]: f = figure()
In [19]: ax = f.add_subplot(111)
In [20]: scatter([3,5,2,6,8],[5,3,2,1,5])
Out[20]: <matplotlib.collections.CircleCollection object at 0x0000000007439A90>
In [21]: text(0.1, 0.9,'matplotlib', ha='center', va='center', transform=ax.transAxes)
Out[21]: <matplotlib.text.Text object at 0x0000000007415B38>
In [22]:
The ha and va parameters set the alignment of your text relative to the insertion point. ie. ha='left' is a good set to prevent a long text to go out of the left axis when the frame is reduced (made narrower) manually.
Open window in JavaScript with HTML inserted
You can also create an "example.html" page which has your desired html and give that page's url as parameter to window.open
var url = '/example.html';
var myWindow = window.open(url, "", "width=800,height=600");
Split comma separated column data into additional columns
You can use split function.
SELECT
(select top 1 item from dbo.Split(FullName,',') where id=1 ) Column1,
(select top 1 item from dbo.Split(FullName,',') where id=2 ) Column2,
(select top 1 item from dbo.Split(FullName,',') where id=3 ) Column3,
(select top 1 item from dbo.Split(FullName,',') where id=4 ) Column4,
FROM MyTbl
No process is on the other end of the pipe (SQL Server 2012)
Always try to log in using those credentials with SQL Management Studio. This might reveal some more details that you don't get at runtime in your code.
I had checked the SQL + Windows authentication, restarted the server but still no luck.
After trying to log in using SQL Management, I got this prompt:
Somehow the password had expired although the login was created just minutes before. Anyway, new password set, connection string updated and all's fine.
glm rotate usage in Opengl
You need to multiply your Model matrix. Because that is where model position, scaling and rotation should be (that's why it's called the model matrix).
All you need to do is (see here)
Model = glm::rotate(Model, angle_in_radians, glm::vec3(x, y, z)); // where x, y, z is axis of rotation (e.g. 0 1 0)
Note that to convert from degrees to radians, use glm::radians(degrees)
That takes the Model matrix and applies rotation on top of all the operations that are already in there. The other functions translate and scale do the same. That way it's possible to combine many transformations in a single matrix.
note: earlier versions accepted angles in degrees. This is deprecated since 0.9.6
Model = glm::rotate(Model, angle_in_degrees, glm::vec3(x, y, z)); // where x, y, z is axis of rotation (e.g. 0 1 0)
Get file name from a file location in Java
Here are 2 ways(both are OS independent.)
Using Paths
: Since 1.7
Path p = Paths.get(<Absolute Path of Linux/Windows system>);
String fileName = p.getFileName().toString();
String directory = p.getParent().toString();
Using FilenameUtils
in Apache Commons IO :
String name1 = FilenameUtils.getName("/ab/cd/xyz.txt");
String name2 = FilenameUtils.getName("c:\\ab\\cd\\xyz.txt");
Passing struct to function
The line function implementation should be:
void addStudent(struct student person) {
}
person
is not a type but a variable, you cannot use it as the type of a function parameter.
Also, make sure your struct is defined before the prototype of the function addStudent
as the prototype uses it.
SQL SELECT WHERE field contains words
SELECT * FROM MyTable WHERE
Column1 LIKE '%word1%'
AND Column1 LIKE '%word2%'
AND Column1 LIKE '%word3%'
Changed OR
to AND
based on edit to question.
sql select with column name like
You cannot with standard SQL. Column names are not treated like data in SQL.
If you use a SQL engine that has, say, meta-data tables storing column names, types, etc. you may select on that table instead.
SSH to Elastic Beanstalk instance
Depending on your environment configuration, you may not have a public IP address on the EC2 instance that was created for your environment. You can check by:
- Go to the EC2 Console
- Find your instance and check the Description tab
- If there is no Public IP...
- Click Elastic IPs on the Navigation
- Click Allocate new address
- Choose Amazon for the pool
- Click Allocate
Finally, select your new EIP and choose Associate address from the action menu. Associate that IP with your EC2 instance. You should be able to connect using eb ssh
now.
You can reset the connection details by running eb ssh --setup
.
Difference between a Seq and a List in Scala
As @daniel-c-sobral said, List extends the trait Seq and is an abstract class implemented by scala.collection.immutable.$colon$colon
(or ::
for short), but technicalities aside, mind that most of lists and seqs we use are initialized in the form of Seq(1, 2, 3)
or List(1, 2, 3)
which both return scala.collection.immutable.$colon$colon
, hence one can write:
var x: scala.collection.immutable.$colon$colon[Int] = null
x = Seq(1, 2, 3).asInstanceOf[scala.collection.immutable.$colon$colon[Int]]
x = List(1, 2, 3).asInstanceOf[scala.collection.immutable.$colon$colon[Int]]
As a result, I'd argue than the only thing that matters are the methods you want to expose, for instance to prepend you can use ::
from List that I find redundant with +:
from Seq and I personally stick to Seq by default.
Unable to load script from assets index.android.bundle on windows
I spent hours trying to figure this issue out. My problem was not specific to Windows but is specific to Android.
Accessing the development server worked locally and in the emulator's browser. The only thing that did not work was accessing the development server in the app.
Starting with Android 9.0 (API level 28), cleartext support is disabled by default.
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest ...>
<uses-permission android:name="android.permission.INTERNET" />
<application
...
android:usesCleartextTraffic="true"
...>
...
</application>
</manifest>
See for more info:
https://stackoverflow.com/a/50834600/1713216
Explaining Python's '__enter__' and '__exit__'
try adding my answers (my thought of learning) :
__enter__
and [__exit__]
both are methods that are invoked on entry to and exit from the body of "the with statement" (PEP 343) and implementation of both is called context manager.
the with statement is intend to hiding flow control of try finally clause and make the code inscrutable.
the syntax of the with statement is :
with EXPR as VAR:
BLOCK
which translate to (as mention in PEP 343) :
mgr = (EXPR)
exit = type(mgr).__exit__ # Not calling it yet
value = type(mgr).__enter__(mgr)
exc = True
try:
try:
VAR = value # Only if "as VAR" is present
BLOCK
except:
# The exceptional case is handled here
exc = False
if not exit(mgr, *sys.exc_info()):
raise
# The exception is swallowed if exit() returns true
finally:
# The normal and non-local-goto cases are handled here
if exc:
exit(mgr, None, None, None)
try some code:
>>> import logging
>>> import socket
>>> import sys
#server socket on another terminal / python interpreter
>>> s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
>>> s.listen(5)
>>> s.bind((socket.gethostname(), 999))
>>> while True:
>>> (clientsocket, addr) = s.accept()
>>> print('get connection from %r' % addr[0])
>>> msg = clientsocket.recv(1024)
>>> print('received %r' % msg)
>>> clientsocket.send(b'connected')
>>> continue
#the client side
>>> class MyConnectionManager:
>>> def __init__(self, sock, addrs):
>>> logging.basicConfig(level=logging.DEBUG, format='%(asctime)s \
>>> : %(levelname)s --> %(message)s')
>>> logging.info('Initiating My connection')
>>> self.sock = sock
>>> self.addrs = addrs
>>> def __enter__(self):
>>> try:
>>> self.sock.connect(addrs)
>>> logging.info('connection success')
>>> return self.sock
>>> except:
>>> logging.warning('Connection refused')
>>> raise
>>> def __exit__(self, type, value, tb):
>>> logging.info('CM suppress exception')
>>> return False
>>> addrs = (socket.gethostname())
>>> s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
>>> with MyConnectionManager(s, addrs) as CM:
>>> try:
>>> CM.send(b'establishing connection')
>>> msg = CM.recv(1024)
>>> print(msg)
>>> except:
>>> raise
#will result (client side) :
2018-12-18 14:44:05,863 : INFO --> Initiating My connection
2018-12-18 14:44:05,863 : INFO --> connection success
b'connected'
2018-12-18 14:44:05,864 : INFO --> CM suppress exception
#result of server side
get connection from '127.0.0.1'
received b'establishing connection'
and now try manually (following translate syntax):
>>> s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) #make new socket object
>>> mgr = MyConnection(s, addrs)
2018-12-18 14:53:19,331 : INFO --> Initiating My connection
>>> ext = mgr.__exit__
>>> value = mgr.__enter__()
2018-12-18 14:55:55,491 : INFO --> connection success
>>> exc = True
>>> try:
>>> try:
>>> VAR = value
>>> VAR.send(b'establishing connection')
>>> msg = VAR.recv(1024)
>>> print(msg)
>>> except:
>>> exc = False
>>> if not ext(*sys.exc_info()):
>>> raise
>>> finally:
>>> if exc:
>>> ext(None, None, None)
#the result:
b'connected'
2018-12-18 15:01:54,208 : INFO --> CM suppress exception
the result of the server side same as before
sorry for my bad english and my unclear explanations, thank you....
What is the maximum size of a web browser's cookie's key?
Actually, RFC 2965, the document that defines how cookies work, specifies that there should be no maximum length of a cookie's key or value size, and encourages implementations to support arbitrarily large cookies. Each browser's implementation maximum will necessarily be different, so consult individual browser documentation.
See section 5.3, "Implementation Limits", in the RFC.
How to create a unique index on a NULL column?
The calculated column trick is widely known as a "nullbuster"; my notes credit Steve Kass:
CREATE TABLE dupNulls (
pk int identity(1,1) primary key,
X int NULL,
nullbuster as (case when X is null then pk else 0 end),
CONSTRAINT dupNulls_uqX UNIQUE (X,nullbuster)
)
Python/Json:Expecting property name enclosed in double quotes
I had the same problem and what I did is to replace the single quotes with the double one, but what was worse is the fact I had the same error when I had a comma for the last attribute of the json object. So I used regex in python to replace it before using the json.loads()
function. (Be careful about the s at the end of "loads")
import re
with open("file.json", 'r') as f:
s = f.read()
correct_format = re.sub(", *\n *}", "}", s)
data_json = json.loads(correct_format)
The used regex return each comma followed by a newline and "}", replacing it just with a "}".
How to bundle vendor scripts separately and require them as needed with Webpack?
In case you're interested in bundling automatically your scripts separately from vendors ones:
var webpack = require('webpack'),
pkg = require('./package.json'), //loads npm config file
html = require('html-webpack-plugin');
module.exports = {
context : __dirname + '/app',
entry : {
app : __dirname + '/app/index.js',
vendor : Object.keys(pkg.dependencies) //get npm vendors deps from config
},
output : {
path : __dirname + '/dist',
filename : 'app.min-[hash:6].js'
},
plugins: [
//Finally add this line to bundle the vendor code separately
new webpack.optimize.CommonsChunkPlugin('vendor', 'vendor.min-[hash:6].js'),
new html({template : __dirname + '/app/index.html'})
]
};
You can read more about this feature in official documentation.
Using python's eval() vs. ast.literal_eval()?
If all you need is a user provided dictionary, possible better solution is json.loads
. The main limitation is that json dicts requires string keys. Also you can only provide literal data, but that is also the case for literal_eval
.
Reading file using fscanf() in C
First of all, you're testing fp
twice. so printf("Error Reading File\n");
never gets executed.
Then, the output of fscanf
should be equal to 2
since you're reading two values.
Javascript to export html table to Excel
If you add:
<meta http-equiv="content-type" content="text/plain; charset=UTF-8"/>
in the head of the document it will start working as expected:
<script type="text/javascript">
var tableToExcel = (function() {
var uri = 'data:application/vnd.ms-excel;base64,'
, template = '<html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns="http://www.w3.org/TR/REC-html40"><head><!--[if gte mso 9]><xml><x:ExcelWorkbook><x:ExcelWorksheets><x:ExcelWorksheet><x:Name>{worksheet}</x:Name><x:WorksheetOptions><x:DisplayGridlines/></x:WorksheetOptions></x:ExcelWorksheet></x:ExcelWorksheets></x:ExcelWorkbook></xml><![endif]--><meta http-equiv="content-type" content="text/plain; charset=UTF-8"/></head><body><table>{table}</table></body></html>'
, base64 = function(s) { return window.btoa(unescape(encodeURIComponent(s))) }
, format = function(s, c) { return s.replace(/{(\w+)}/g, function(m, p) { return c[p]; }) }
return function(table, name) {
if (!table.nodeType) table = document.getElementById(table)
var ctx = {worksheet: name || 'Worksheet', table: table.innerHTML}
window.location.href = uri + base64(format(template, ctx))
}
})()
</script>
Updated Fiddle Here.
What is the difference between UTF-8 and Unicode?
Unicode is a standard that defines, along with ISO/IEC 10646, Universal Character Set (UCS) which is a superset of all existing characters required to represent practically all known languages.
Unicode assigns a Name and a Number (Character Code, or Code-Point) to each character in its repertoire.
UTF-8 encoding, is a way to represent these characters digitally in computer memory. UTF-8 maps each code-point into a sequence of octets (8-bit bytes)
For e.g.,
UCS Character = Unicode Han Character
UCS code-point = U+24B62
UTF-8 encoding = F0 A4 AD A2 (hex) = 11110000 10100100 10101101 10100010 (bin)
customize Android Facebook Login button
You can use styles for modifiy the login button like this
<style name="FacebookLoginButton">
<item name="android:textSize">@dimen/smallTxtSize</item>
<item name="android:background">@drawable/facebook_signin_btn</item>
<item name="android:layout_marginTop">10dp</item>
<item name="android:layout_marginBottom">10dp</item>
<item name="android:layout_gravity">center_horizontal</item>
</style>
and in layout
<com.facebook.widget.LoginButton
xmlns:fb="http://schemas.android.com/apk/res-auto"
android:id="@+id/loginFacebookButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
fb:login_text="@string/loginFacebookButton"
fb:logout_text=""
style="@style/FacebookLoginButton"/>
Get Base64 encode file-data from Input Form
I used FileReader to display image on click of the file upload button not using any Ajax requests. Following is the code hope it might help some one.
$(document).ready(function($) {
$.extend( true, jQuery.fn, {
imagePreview: function( options ){
var defaults = {};
if( options ){
$.extend( true, defaults, options );
}
$.each( this, function(){
var $this = $( this );
$this.bind( 'change', function( evt ){
var files = evt.target.files; // FileList object
// Loop through the FileList and render image files as thumbnails.
for (var i = 0, f; f = files[i]; i++) {
// Only process image files.
if (!f.type.match('image.*')) {
continue;
}
var reader = new FileReader();
// Closure to capture the file information.
reader.onload = (function(theFile) {
return function(e) {
// Render thumbnail.
$('#imageURL').attr('src',e.target.result);
};
})(f);
// Read in the image file as a data URL.
reader.readAsDataURL(f);
}
});
});
}
});
$( '#fileinput' ).imagePreview();
});
File input 'accept' attribute - is it useful?
It's been a few years, and Chrome at least makes use of this attribute. This attribute is very useful from a usability standpoint as it will filter out the unnecessary files for the user, making their experience smoother. However, the user can still select "all files" from the type (or otherwise bypass the filter), thus you should always validate the file where it is actually used; If you're using it on the server, validate it there before using it. The user can always bypass any client-side scripting.
Font Awesome not working, icons showing as squares
It could be possible that your font path is not correct so that css not able to load the font and render the icons so you need to provide the stranded path of attached fonts.
@font-face {
font-family: "FontAwesome";
src: url("fonts/fontawesome-webfont.eot");
}
Rename specific column(s) in pandas
A much faster implementation would be to use list-comprehension
if you need to rename a single column.
df.columns = ['log(gdp)' if x=='gdp' else x for x in df.columns]
If the need arises to rename multiple columns, either use conditional expressions like:
df.columns = ['log(gdp)' if x=='gdp' else 'cap_mod' if x=='cap' else x for x in df.columns]
Or, construct a mapping using a dictionary
and perform the list-comprehension
with it's get
operation by setting default value as the old name:
col_dict = {'gdp': 'log(gdp)', 'cap': 'cap_mod'} ## key?old name, value?new name
df.columns = [col_dict.get(x, x) for x in df.columns]
Timings:
%%timeit
df.rename(columns={'gdp':'log(gdp)'}, inplace=True)
10000 loops, best of 3: 168 µs per loop
%%timeit
df.columns = ['log(gdp)' if x=='gdp' else x for x in df.columns]
10000 loops, best of 3: 58.5 µs per loop
MySQL TEXT vs BLOB vs CLOB
It's worth to mention that CLOB / BLOB data types and their sizes are supported by MySQL 5.0+, so you can choose the proper data type for your need.
http://dev.mysql.com/doc/refman/5.7/en/storage-requirements.html
Data Type Date Type Storage Required
(CLOB) (BLOB)
TINYTEXT TINYBLOB L + 1 bytes, where L < 2**8 (255)
TEXT BLOB L + 2 bytes, where L < 2**16 (64 K)
MEDIUMTEXT MEDIUMBLOB L + 3 bytes, where L < 2**24 (16 MB)
LONGTEXT LONGBLOB L + 4 bytes, where L < 2**32 (4 GB)
where L stands for the byte length of a string
When you use 'badidea' or 'thisisunsafe' to bypass a Chrome certificate/HSTS error, does it only apply for the current site?
I'm a PHP developer and to be able to work on my development environment with a certificate, I was able to do the same by finding the real SSL HTTPS/HTTP Certificate and deleting it.
The steps are :
- In the address bar, type "chrome://net-internals/#hsts".
- Type the domain
name in the text field below "Delete domain".
- Click the "Delete" button.
- Type the domain name in the text field below "Query domain".
- Click the "Query" button.
- Your response should be "Not found".
You can find more information at :
http://classically.me/blogs/how-clear-hsts-settings-major-browsers
Although this solution is not the best, Chrome currently does not have any good solution for the moment. I have escalated this situation with their support team to help improve user experience.
Edit : you have to repeat the steps every time you will go on the production site.
github: server certificate verification failed
You can also disable SSL verification, (if the project does not require a high level of security other than login/password) by typing :
git config --global http.sslverify false
enjoy git :)
Close Current Tab
As of Chrome 46, a simple onclick=window.close()
does the trick. This only closes the tab, and not the entire browser, if multiple tabs are opened.
Using Mockito to test abstract classes
Mocking frameworks are designed to make it easier to mock out dependencies of the class you are testing. When you use a mocking framework to mock a class, most frameworks dynamically create a subclass, and replace the method implementation with code for detecting when a method is called and returning a fake value.
When testing an abstract class, you want to execute the non-abstract methods of the Subject Under Test (SUT), so a mocking framework isn't what you want.
Part of the confusion is that the answer to the question you linked to said to hand-craft a mock that extends from your abstract class. I wouldn't call such a class a mock. A mock is a class that is used as a replacement for a dependency, is programmed with expectations, and can be queried to see if those expectations are met.
Instead, I suggest defining a non-abstract subclass of your abstract class in your test. If that results in too much code, than that may be a sign that your class is difficult to extend.
An alternative solution would be to make your test case itself abstract, with an abstract method for creating the SUT (in other words, the test case would use the Template Method design pattern).
Check empty string in Swift?
Check check for only spaces and newlines characters in text
extension String
{
var isBlank:Bool {
return self.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet()).isEmpty
}
}
using
if text.isBlank
{
//text is blank do smth
}
How to revert a merge commit that's already pushed to remote branch?
The correctly marked answer worked for me but I had to spend some time to determine whats going on.. So I decided to add an answer with simple straightforward steps for cases like mine..
Lets say we got branches A and B.. You merged branch A into branch B and pushed branch B to itself so now the merge is part of it.. But you want to go back to the last commit before the merge.. What do you do?
- Go to your git root folder (the project folder usually) and use
git log
You will see the history of recent commits - the commits have commit/author/date properties while the merges also have a merge property - so you see them like this:
commit: <commitHash>
Merge: <parentHashA> <parentHashB>
Author: <author>
Date: <date>
Use git log <parentHashA>
and git log <parentHashB>
- you will see the commit histories of those parent branches - the first commits in the list are the latest ones
- Take the
<commitHash>
of the commit you want, go to your git root folder and use git checkout -b <newBranchName> <commitHash>
- that will create a new branch starting from that last commit you've chosen before the merge.. Voila, ready!
Virtualenv Command Not Found
I think your problem can be solved using a simple symbolic link, but you are creating the symbolic link to the wrong file. As far as I know virtualenv is installed to /Library/Frameworks/Python.framework/Versions/2.7/bin/virtualenv
, (you can change the numbers for your Python version) so the command for creating the symbolic link should be:
ln -s /Library/Frameworks/Python.framework/Versions/2.7/bin/virtualenv /usr/local/bin/virtualenv
html text input onchange event
Well unless I misunderstand you can just use the onChange
attribute:
<input type="text" onChange="return bar()">
Note: in FF 3 (at least) this is not called until some the user has confirmed they are changed either by clicking away from the element, clicking enter, or other.
What is the height of iPhone's onscreen keyboard?
I created this table which contains both the heights of iPhone and iPad keyboards, both for landscape and portrait mode, both with the toolbar on and off.
I even explained how you can use these dimensions in your code here.
Note that you should only use these dimensions if you need to know the keyboard's dimension before you layout the view. Otherwise the solutions from the other answers work better.
kill a process in bash
You have a multiple options:
First, you can use kill. But you need the pid of your process, which you can get by using ps, pidof or pgrep.
ps -A // to get the pid, can be combined with grep
-or-
pidof <name>
-or-
pgrep <name>
kill <pid>
It is possible to kill a process by just knowing the name. Use pkill or killall.
pkill <name>
-or-
killall <name>
All commands send a signal to the process. If the process hung up, it might be neccessary to send a sigkill to the process (this is signal number 9, so the following examples do the same):
pkill -9 <name>
pkill -SIGKILL <name>
You can use this option with kill
and killall
, too.
Read this article about controlling processes to get more informations about processes in general.
Bind TextBox on Enter-key press
A different solution (not using xaml but still quite clean I think).
class ReturnKeyTextBox : TextBox
{
protected override void OnKeyUp(KeyEventArgs e)
{
base.OnKeyUp(e);
if (e.Key == Key.Return)
GetBindingExpression(TextProperty).UpdateSource();
}
}
How to scroll up or down the page to an anchor using jQuery?
SS Slow Scroll
This solution does not require anchor tags but you do of course need to match the menu button (arbitrary attribute, 'ss' in example) with the destination element id in your html.
ss="about"
takes you to id="about"
_x000D_
_x000D_
$('.menu-item').click(function() {_x000D_
var keyword = $(this).attr('ss');_x000D_
var scrollTo = $('#' + keyword);_x000D_
$('html, body').animate({_x000D_
scrollTop: scrollTo.offset().top_x000D_
}, 'slow');_x000D_
});
_x000D_
.menu-wrapper {_x000D_
display: flex;_x000D_
margin-bottom: 500px;_x000D_
}_x000D_
.menu-item {_x000D_
display: flex;_x000D_
justify-content: center;_x000D_
flex: 1;_x000D_
font-size: 20px;_x000D_
line-height: 30px;_x000D_
color: hsla(0, 0%, 80%, 1);_x000D_
background-color: hsla(0, 0%, 20%, 1);_x000D_
cursor: pointer;_x000D_
}_x000D_
.menu-item:hover {_x000D_
background-color: hsla(0, 40%, 40%, 1);_x000D_
}_x000D_
_x000D_
.content-block-header {_x000D_
display: flex;_x000D_
justify-content: center;_x000D_
font-size: 20px;_x000D_
line-height: 30px;_x000D_
color: hsla(0, 0%, 90%, 1);_x000D_
background-color: hsla(0, 50%, 50%, 1);_x000D_
}
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>_x000D_
<div class="menu-wrapper">_x000D_
<div class="menu-item" ss="about">About Us</div>_x000D_
<div class="menu-item" ss="services">Services</div>_x000D_
<div class="menu-item" ss="contact">Contact</div>_x000D_
</div>_x000D_
_x000D_
<div class="content-block-header" id="about">About Us</div>_x000D_
<div class="content-block">_x000D_
Lorem ipsum dolor sit we gonna chung, crazy adipiscing phat. Nullizzle sapizzle velizzle, shut the shizzle up volutpizzle, suscipizzle quizzle, away vizzle, arcu. Pellentesque my shizz sure. Sed erizzle. I'm in the shizzle izzle funky fresh dapibus turpis tempus shizzlin dizzle. Maurizzle my shizz nibh izzle turpizzle. Gangsta izzle fo shizzle mah nizzle fo rizzle, mah home g-dizzle. I'm in the shizzle eleifend rhoncizzle fo shizzle my nizzle. In rizzle habitasse crazy dictumst. Yo dapibus. Curabitizzle tellizzle urna, pretizzle break it down, mattis izzle, eleifend rizzle, nunc. My shizz suscipit. Integer check it out funky fresh sizzle pizzle._x000D_
_x000D_
That's the shizzle et dizzle quis nisi sheezy mollis. Suspendisse bizzle. Morbi odio. Vivamizzle boofron. Crizzle orci. Cras mauris its fo rizzle, interdizzle a, we gonna chung amizzle, break it down izzle, pizzle. Pellentesque rizzle. Vestibulum its fo rizzle mi, volutpat uhuh ... yih!, ass funky fresh, adipiscing semper, fo shizzle. Crizzle izzle ipsum. We gonna chung mammasay mammasa mamma oo sa stuff brizzle yo. Cras ass justo nizzle purizzle sodales break it down. Check it out venenatizzle justo yo shut the shizzle up. Nunc crackalackin. Suspendisse bow wow wow placerizzle sure. Fizzle eu ante. Nunc that's the shizzle, leo eu gangster hendrerizzle, gangsta felis elementum pizzle, sizzle aliquizzle crunk bizzle luctus pede. Nam a nisl. Fo shizzle da bomb taciti gangster stuff i'm in the shizzle i'm in the shizzle per conubia you son of a bizzle, per inceptos its fo rizzle. Check it out break it down, neque izzle cool nonummy, tellivizzle orci viverra leo, bizzle semper risizzle arcu fo shizzle mah nizzle._x000D_
</div>_x000D_
<div class="content-block-header" id="services">Services</div>_x000D_
<div class="content-block">_x000D_
Lorem ipsum dolor sit we gonna chung, crazy adipiscing phat. Nullizzle sapizzle velizzle, shut the shizzle up volutpizzle, suscipizzle quizzle, away vizzle, arcu. Pellentesque my shizz sure. Sed erizzle. I'm in the shizzle izzle funky fresh dapibus turpis tempus shizzlin dizzle. Maurizzle my shizz nibh izzle turpizzle. Gangsta izzle fo shizzle mah nizzle fo rizzle, mah home g-dizzle. I'm in the shizzle eleifend rhoncizzle fo shizzle my nizzle. In rizzle habitasse crazy dictumst. Yo dapibus. Curabitizzle tellizzle urna, pretizzle break it down, mattis izzle, eleifend rizzle, nunc. My shizz suscipit. Integer check it out funky fresh sizzle pizzle._x000D_
_x000D_
That's the shizzle et dizzle quis nisi sheezy mollis. Suspendisse bizzle. Morbi odio. Vivamizzle boofron. Crizzle orci. Cras mauris its fo rizzle, interdizzle a, we gonna chung amizzle, break it down izzle, pizzle. Pellentesque rizzle. Vestibulum its fo rizzle mi, volutpat uhuh ... yih!, ass funky fresh, adipiscing semper, fo shizzle. Crizzle izzle ipsum. We gonna chung mammasay mammasa mamma oo sa stuff brizzle yo. Cras ass justo nizzle purizzle sodales break it down. Check it out venenatizzle justo yo shut the shizzle up. Nunc crackalackin. Suspendisse bow wow wow placerizzle sure. Fizzle eu ante. Nunc that's the shizzle, leo eu gangster hendrerizzle, gangsta felis elementum pizzle, sizzle aliquizzle crunk bizzle luctus pede. Nam a nisl. Fo shizzle da bomb taciti gangster stuff i'm in the shizzle i'm in the shizzle per conubia you son of a bizzle, per inceptos its fo rizzle. Check it out break it down, neque izzle cool nonummy, tellivizzle orci viverra leo, bizzle semper risizzle arcu fo shizzle mah nizzle._x000D_
</div>_x000D_
<div class="content-block-header" id="contact">Contact</div>_x000D_
<div class="content-block">_x000D_
Lorem ipsum dolor sit we gonna chung, crazy adipiscing phat. Nullizzle sapizzle velizzle, shut the shizzle up volutpizzle, suscipizzle quizzle, away vizzle, arcu. Pellentesque my shizz sure. Sed erizzle. I'm in the shizzle izzle funky fresh dapibus turpis tempus shizzlin dizzle. Maurizzle my shizz nibh izzle turpizzle. Gangsta izzle fo shizzle mah nizzle fo rizzle, mah home g-dizzle. I'm in the shizzle eleifend rhoncizzle fo shizzle my nizzle. In rizzle habitasse crazy dictumst. Yo dapibus. Curabitizzle tellizzle urna, pretizzle break it down, mattis izzle, eleifend rizzle, nunc. My shizz suscipit. Integer check it out funky fresh sizzle pizzle._x000D_
_x000D_
That's the shizzle et dizzle quis nisi sheezy mollis. Suspendisse bizzle. Morbi odio. Vivamizzle boofron. Crizzle orci. Cras mauris its fo rizzle, interdizzle a, we gonna chung amizzle, break it down izzle, pizzle. Pellentesque rizzle. Vestibulum its fo rizzle mi, volutpat uhuh ... yih!, ass funky fresh, adipiscing semper, fo shizzle. Crizzle izzle ipsum. We gonna chung mammasay mammasa mamma oo sa stuff brizzle yo. Cras ass justo nizzle purizzle sodales break it down. Check it out venenatizzle justo yo shut the shizzle up. Nunc crackalackin. Suspendisse bow wow wow placerizzle sure. Fizzle eu ante. Nunc that's the shizzle, leo eu gangster hendrerizzle, gangsta felis elementum pizzle, sizzle aliquizzle crunk bizzle luctus pede. Nam a nisl. Fo shizzle da bomb taciti gangster stuff i'm in the shizzle i'm in the shizzle per conubia you son of a bizzle, per inceptos its fo rizzle. Check it out break it down, neque izzle cool nonummy, tellivizzle orci viverra leo, bizzle semper risizzle arcu fo shizzle mah nizzle._x000D_
</div>
_x000D_
_x000D_
_x000D_
Fiddle
https://jsfiddle.net/Hastig/stcstmph/4/
SVN Error - Not a working copy
I also meet this problem in svn diff operation, it was caused by incorrect file path, you should add './'
to indicate the current file directory.
How to change angular port from 4200 to any other
If you have more than one enviroment, you may add the following way in the angular.json
:
"serve": {
"builder": "@angular-devkit/build-angular:dev-server",
"options": {
"browserTarget": "your_project:build"
},
"configurations": {
"production": {
"browserTarget": "your_project:build:production"
},
"es5": {
"browserTarget": "your_project:build:es5"
},
"local": {
"browserTarget": "your_project:build:local",
"port": 4201
},
"uat": {
"browserTarget": "your_project:build:uat"
}
}
},
This way only the local points to another port.
Annotation @Transactional. How to rollback?
For me rollbackFor was not enough, so I had to put this and it works as expected:
@Transactional(propagation = Propagation.REQUIRED, readOnly = false, rollbackFor = Exception.class)
I hope it helps :-)
How do I check if I'm running on Windows in Python?
Python os module
Specifically for Python 3.6/3.7:
os.name
: The name of the operating
system dependent module imported. The
following names have currently been
registered: 'posix', 'nt', 'java'.
In your case, you want to check for 'nt' as os.name
output:
import os
if os.name == 'nt':
...
There is also a note on os.name
:
See also sys.platform
has a finer granularity. os.uname()
gives
system-dependent version information.
The platform module provides
detailed checks for the system’s identity.
Gnuplot line types
Until version 4.6
The dash type of a linestyle
is given by the linetype
, which does also select the line color unless you explicitely set an other one with linecolor
.
However, the support for dashed lines depends on the selected terminal:
- Some terminals don't support dashed lines, like
png
(uses libgd
)
- Other terminals, like
pngcairo
, support dashed lines, but it is disables by default. To enable it, use set termoption dashed
, or set terminal pngcairo dashed ...
.
- The exact dash patterns differ between terminals. To see the defined
linetype
, use the test
command:
Running
set terminal pngcairo dashed
set output 'test.png'
test
set output
gives:
whereas, the postscript
terminal shows different dash patterns:
set terminal postscript eps color colortext
set output 'test.eps'
test
set output
Version 5.0
Starting with version 5.0 the following changes related to linetypes, dash patterns and line colors are introduced:
A new dashtype
parameter was introduced:
To get the predefined dash patterns, use e.g.
plot x dashtype 2
You can also specify custom dash patterns like
plot x dashtype (3,5,10,5),\
2*x dashtype '.-_'
The terminal options dashed
and solid
are ignored. By default all lines are solid. To change them to dashed, use e.g.
set for [i=1:8] linetype i dashtype i
The default set of line colors was changed. You can select between three different color sets with set colorsequence default|podo|classic
:
How to get elements with multiple classes
Okay this code does exactly what you need:
HTML:
<div class="class1">nothing happens hear.</div>
<div class="class1 class2">This element will receive yout code.</div>
<div class="class1">nothing happens hear.</div>
JS:
function getElementMultipleClasses() {
var x = document.getElementsByClassName("class1 class2");
x[0].innerHTML = "This is the element you want";
}
getElementMultipleClasses();
Hope it helps! ;)
Call a Javascript function every 5 seconds continuously
As best coding practices suggests, use setTimeout
instead of setInterval
.
function foo() {
// your function code here
setTimeout(foo, 5000);
}
foo();
Please note that this is NOT a recursive function. The function is not calling itself before it ends, it's calling a setTimeout
function that will be later call the same function again.
Arithmetic overflow error converting numeric to data type numeric
I feel I need to clarify one very important thing, for others (like my co-worker) who came across this thread and got the wrong information.
The answer given ("Try decimal(9,2) or decimal(10,2) or whatever.") is correct, but the reason ("increase the number of digits before the decimal") is wrong.
decimal(p,s) and numeric(p,s) both specify a Precision and a Scale. The "precision" is not the number of digits to the left of the decimal, but instead is the total precision of the number.
For example:
decimal(2,1) covers 0.0 to 9.9, because the precision is 2 digits (00 to 99) and the scale is 1.
decimal(4,1) covers 000.0 to 999.9
decimal(4,2) covers 00.00 to 99.99
decimal(4,3) covers 0.000 to 9.999
What is SOA "in plain english"?
You might find this article (What is SOA? - SOA and Web Services Explained ) helpful.
A little teaser:
SOA is a style of architecting applications in such a way that they are composed of discrete software agents that have simple, well defined interfaces and are orchestrated through a loose coupling to perform a required function.
There are 2 roles in SOA- a service provider and a service consumer. A software agent may play both roles. SOA is not an entirely new concept – however, this article mainly focuses on SOA as implemented with web services.
How to prevent errno 32 broken pipe?
This might be because you are using two method for inserting data into database and this cause the site to slow down.
def add_subscriber(request, email=None):
if request.method == 'POST':
email = request.POST['email_field']
e = Subscriber.objects.create(email=email).save() <====
return HttpResponseRedirect('/')
else:
return HttpResponseRedirect('/')
In above function, the error is where arrow is pointing. The correct implementation is below:
def add_subscriber(request, email=None):
if request.method == 'POST':
email = request.POST['email_field']
e = Subscriber.objects.create(email=email)
return HttpResponseRedirect('/')
else:
return HttpResponseRedirect('/')
sending email via php mail function goes to spam
The problem is simple that the PHP-Mail function is not using a well configured SMTP Server.
Nowadays Email-Clients and Servers perform massive checks on the emails sending server, like Reverse-DNS-Lookups, Graylisting and whatevs. All this tests will fail with the php mail() function. If you are using a dynamic ip, its even worse.
Use the PHPMailer-Class and configure it to use smtp-auth along with a well configured, dedicated SMTP Server (either a local one, or a remote one) and your problems are gone.
https://github.com/PHPMailer/PHPMailer
Find which commit is currently checked out in Git
If you want to extract just a simple piece of information, you can get that using git show
with the --format=<string>
option...and ask it not to give you the diff with --no-patch
. This means you can get a printf-style output of whatever you want, which might often be a single field.
For instance, to get just the shortened hash (%h
) you could say:
$ git show --format="%h" --no-patch
4b703eb
If you're looking to save that into an environment variable in bash (a likely thing for people to want to do) you can use the $()
syntax:
$ GIT_COMMIT="$(git show --format="%h" --no-patch)"
$ echo $GIT_COMMIT
4b703eb
The full list of what you can do is in git show --help
. But here's an abbreviated list of properties that might be useful:
%H
commit hash
%h
abbreviated commit hash
%T
tree hash
%t
abbreviated tree hash
%P
parent hashes
%p
abbreviated parent hashes
%an
author name
%ae
author email
%at
author date, UNIX timestamp
%aI
author date, strict ISO 8601 format
%cn
committer name
%ce
committer email
%ct
committer date, UNIX timestamp
%cI
committer date, strict ISO 8601 format
%s
subject
%f
sanitized subject line, suitable for a filename
%gD
reflog selector, e.g., refs/stash@{1}
%gd
shortened reflog selector, e.g., stash@{1}
How to show all shared libraries used by executables in Linux?
- Use
ldd
to list shared libraries for each executable.
- Cleanup the output
- Sort, compute counts, sort by count
To find the answer for all executables in the "/bin" directory:
find /bin -type f -perm /a+x -exec ldd {} \; \
| grep so \
| sed -e '/^[^\t]/ d' \
| sed -e 's/\t//' \
| sed -e 's/.*=..//' \
| sed -e 's/ (0.*)//' \
| sort \
| uniq -c \
| sort -n
Change "/bin" above to "/" to search all directories.
Output (for just the /bin directory) will look something like this:
1 /lib64/libexpat.so.0
1 /lib64/libgcc_s.so.1
1 /lib64/libnsl.so.1
1 /lib64/libpcre.so.0
1 /lib64/libproc-3.2.7.so
1 /usr/lib64/libbeecrypt.so.6
1 /usr/lib64/libbz2.so.1
1 /usr/lib64/libelf.so.1
1 /usr/lib64/libpopt.so.0
1 /usr/lib64/librpm-4.4.so
1 /usr/lib64/librpmdb-4.4.so
1 /usr/lib64/librpmio-4.4.so
1 /usr/lib64/libsqlite3.so.0
1 /usr/lib64/libstdc++.so.6
1 /usr/lib64/libz.so.1
2 /lib64/libasound.so.2
2 /lib64/libblkid.so.1
2 /lib64/libdevmapper.so.1.02
2 /lib64/libpam_misc.so.0
2 /lib64/libpam.so.0
2 /lib64/libuuid.so.1
3 /lib64/libaudit.so.0
3 /lib64/libcrypt.so.1
3 /lib64/libdbus-1.so.3
4 /lib64/libresolv.so.2
4 /lib64/libtermcap.so.2
5 /lib64/libacl.so.1
5 /lib64/libattr.so.1
5 /lib64/libcap.so.1
6 /lib64/librt.so.1
7 /lib64/libm.so.6
9 /lib64/libpthread.so.0
13 /lib64/libselinux.so.1
13 /lib64/libsepol.so.1
22 /lib64/libdl.so.2
83 /lib64/ld-linux-x86-64.so.2
83 /lib64/libc.so.6
Edit - Removed "grep -P"
How do I post form data with fetch api?
You can set body
to an instance of URLSearchParams
with query string passed as argument
fetch("/path/to/server", {
method:"POST"
, body:new URLSearchParams("[email protected]&password=pw")
})
_x000D_
_x000D_
document.forms[0].onsubmit = async(e) => {_x000D_
e.preventDefault();_x000D_
const params = new URLSearchParams([...new FormData(e.target).entries()]);_x000D_
// fetch("/path/to/server", {method:"POST", body:params})_x000D_
const response = await new Response(params).text();_x000D_
console.log(response);_x000D_
}
_x000D_
<form>_x000D_
<input name="email" value="[email protected]">_x000D_
<input name="password" value="pw">_x000D_
<input type="submit">_x000D_
</form>
_x000D_
_x000D_
_x000D_
Writing MemoryStream to Response Object
I had the same problem and the only solution that worked was:
Response.Clear();
Response.ContentType = "Application/msword";
Response.AddHeader("Content-Disposition", "attachment; filename=myfile.docx");
Response.BinaryWrite(myMemoryStream.ToArray());
// myMemoryStream.WriteTo(Response.OutputStream); //works too
Response.Flush();
Response.Close();
Response.End();
Add space between two particular <td>s
my choice was to add a td
between the two td
tags and set the width
to 25px
. It can be more or less to your liking. This may be cheesy but it is simple and it works.
How to retrieve data from a SQL Server database in C#?
public Person SomeMethod(string fName)
{
var con = ConfigurationManager.ConnectionStrings["Yourconnection"].ToString();
Person matchingPerson = new Person();
using (SqlConnection myConnection = new SqlConnection(con))
{
string oString = "Select * from Employees where FirstName=@fName";
SqlCommand oCmd = new SqlCommand(oString, myConnection);
oCmd.Parameters.AddWithValue("@Fname", fName);
myConnection.Open();
using (SqlDataReader oReader = oCmd.ExecuteReader())
{
while (oReader.Read())
{
matchingPerson.firstName = oReader["FirstName"].ToString();
matchingPerson.lastName = oReader["LastName"].ToString();
}
myConnection.Close();
}
}
return matchingPerson;
}
Few things to note here: I used a parametrized query, which makes your code safer. The way you are making the select statement with the "where x = "+ Textbox.Text +""
part opens you up to SQL injection.
I've changed this to:
"Select * from Employees where FirstName=@fName"
oCmd.Parameters.AddWithValue("@fname", fName);
So what this block of code is going to do is:
Execute an SQL statement against your database, to see if any there are any firstnames matching the one you provided.
If that is the case, that person will be stored in a Person object (see below in my answer for the class).
If there is no match, the properties of the Person object will be null
.
Obviously I don't exactly know what you are trying to do, so there's a few things to pay attention to: When there are more then 1 persons with a matching name, only the last one will be saved and returned to you.
If you want to be able to store this data, you can add them to a List<Person>
.
Person class to make it cleaner:
public class Person
{
public string firstName { get; set; }
public string lastName { get; set; }
}
Now to call the method:
Person x = SomeMethod("John");
You can then fill your textboxes with values coming from the Person object like so:
txtLastName.Text = x.LastName;
Using SSIS BIDS with Visual Studio 2012 / 2013
Today March 6, 2013, Microsoft released SQL Server Data Tools – Business Intelligence for Visual Studio 2012 (SSDT BI) templates. With SSDT BI for Visual Studio 2012 you can develop and deploy SQL Server Business intelligence projects. Projects created in Visual Studio 2010 can be opened in Visual Studio 2012 and the other way around without upgrading or downgrading – it just works.
The download/install is named to ensure you get the SSDT templates that contain the Business Intelligence projects. The setup for these tools is now available from the web and can be downloaded in multiple languages right here: http://www.microsoft.com/download/details.aspx?id=36843
How to fill the whole canvas with specific color?
You know what, there is an entire library for canvas graphics. It is called p5.js
You can add it with just a single line in your head element and an additional sketch.js file.
Do this to your html and body tags first:
<html style="margin:0 ; padding:0">
<body style="margin:0 ; padding:0">
Add this to your head:
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/0.6.1/p5.js"></script>
<script type="text/javascript" src="sketch.js"></script>
The sketch.js file
function setup() {
createCanvas(windowWidth, windowHeight);
background(r, g, b);
}
Delete terminal history in Linux
If you use bash, then the terminal history is saved in a file called .bash_history. Delete it, and history will be gone.
However, for MySQL the better approach is not to enter the password in the command line. If you just specify the -p option, without a value, then you will be prompted for the password and it won't be logged.
Another option, if you don't want to enter your password every time, is to store it in a my.cnf file. Create a file named ~/.my.cnf with something like:
[client]
user = <username>
password = <password>
Make sure to change the file permissions so that only you can read the file.
Of course, this way your password is still saved in a plaintext file in your home directory, just like it was previously saved in .bash_history.
What is the difference between DTR/DSR and RTS/CTS flow control?
- DTR - Data Terminal Ready
- DSR - Data Set Ready
- RTS - Request To Send
- CTS - Clear To Send
There are multiple ways of doing things because there were never any protocols built into the standards. You use whatever ad-hoc "standard" your equipment implements.
Just based on the names, RTS/CTS would seem to be a natural fit. However, it's backwards from the needs that developed over time. These signals were created at a time when a terminal would batch-send a screen full of data, but the receiver might not be ready, thus the need for flow control. Later the problem would be reversed, as the terminal couldn't keep up with data coming from the host, but the RTS/CTS signals go the wrong direction - the interface isn't orthogonal, and there's no corresponding signals going the other way. Equipment makers adapted as best they could, including using the DTR and DSR signals.
EDIT
To add a bit more detail, its a two level hierarchy so "officially" both must happen for communication to take place. The behavior is defined in the original CCITT (now ITU-T) standard V.28.
The DCE is a modem connecting between the terminal and telephone network. In the telephone network was another piece of equipment which split off to the data network, eg. X.25.
The modem has three states: Powered off, Ready (Data Set Ready is true), and connected (Data Carrier Detect)
The terminal can't do anything until the modem is connected.
When the modem wants to send data, it raises RTS and the modem grants the request with CTS. The modem lowers CTS when its internal buffer is full.
So nostalgic!
Excel how to find values in 1 column exist in the range of values in another
Use the formula by tigeravatar:
=COUNTIF($B$2:$B$5,A2)>0 – tigeravatar Aug 28 '13 at 14:50
as conditional formatting. Highlight column A. Choose conditional formatting by forumula. Enter the formula (above) - this finds values in col B that are also in A. Choose a format (I like to use FILL and a bold color).
To find all of those values, highlight col A. Data > Filter and choose Filter by color.
React.js: Identifying different inputs with one onChange handler
I suggest sticking to standard HTML attributes like name
on input
Elements to identify your inputs. Also, you don't need to keep "total" as a separate value in state because it is composable by adding other values in your state:
var Hello = React.createClass({
getInitialState: function() {
return {input1: 0, input2: 0};
},
render: function() {
const total = this.state.input1 + this.state.input2;
return (
<div>{total}<br/>
<input type="text" value={this.state.input1} name="input1" onChange={this.handleChange} />
<input type="text" value={this.state.input2} name="input2" onChange={this.handleChange} />
</div>
);
},
handleChange: function(e) {
this.setState({[e.target.name]: e.target.value});
}
});
React.renderComponent(<Hello />, document.getElementById('content'));
Display current date and time without punctuation
Without punctuation (as @Burusothman has mentioned):
current_date_time="`date +%Y%m%d%H%M%S`";
echo $current_date_time;
O/P:
20170115072120
With punctuation:
current_date_time="`date "+%Y-%m-%d %H:%M:%S"`";
echo $current_date_time;
O/P:
2017-01-15 07:25:33
if condition in sql server update query
Something like this should work:
UPDATE
table_Name
SET
column_A = CASE WHEN @flag = '1' THEN column_A + @new_value ELSE column_A END,
column_B = CASE WHEN @flag = '0' THEN column_B + @new_value ELSE column_B END
WHERE
ID = @ID
How to do IF NOT EXISTS in SQLite
You can also set a Constraint on a Table with the KEY fields and set On Conflict "Ignore"
When an applicable constraint violation occurs, the IGNORE resolution
algorithm skips the one row that contains the constraint violation and
continues processing subsequent rows of the SQL statement as if
nothing went wrong. Other rows before and after the row that contained
the constraint violation are inserted or updated normally. No error is
returned when the IGNORE conflict resolution algorithm is used.
SQLite Documentation
Get a JSON object from a HTTP response
You need to use JSONObject
like below:
String mJsonString = downloadFileFromInternet(urls[0]);
JSONObject jObject = null;
try {
jObject = new JSONObject(mJsonString);
}
catch (JSONException e) {
e.printStackTrace();
return false;
}
...
private String downloadFileFromInternet(String url)
{
if(url == null /*|| url.isEmpty() == true*/)
new IllegalArgumentException("url is empty/null");
StringBuilder sb = new StringBuilder();
InputStream inStream = null;
try
{
url = urlEncode(url);
URL link = new URL(url);
inStream = link.openStream();
int i;
int total = 0;
byte[] buffer = new byte[8 * 1024];
while((i=inStream.read(buffer)) != -1)
{
if(total >= (1024 * 1024))
{
return "";
}
total += i;
sb.append(new String(buffer,0,i));
}
}
catch(Exception e )
{
e.printStackTrace();
return null;
}catch(OutOfMemoryError e)
{
e.printStackTrace();
return null;
}
return sb.toString();
}
private String urlEncode(String url)
{
if(url == null /*|| url.isEmpty() == true*/)
return null;
url = url.replace("[","");
url = url.replace("]","");
url = url.replaceAll(" ","%20");
return url;
}
Hope this helps you..
Vim multiline editing like in sublimetext?
There are several ways to accomplish that in Vim. I don't know which are most
similar to Sublime Text's though.
The first one would be via multiline insert mode. Put your cursor to the
second "a" in the first line, press Ctrl-V
, select all lines, then press I
, and
put in a doublequote. Pressing <esc>
will repeat the operation on every line.
The second one is via macros. Put the cursor on the first character, and start
recording a macro with qa
.
Go the your right with llll
, enter insert mode with
a
, put down a doublequote, exit insert mode, and go back to the beginning of
your row with <home>
(or equivalent). Press j
to move down one row.
Stop recording with q
.
And then replay the macro with @a
. Several times.
Does any of the above approaches work for you?
How to check which locks are held on a table
You can also use the built-in sp_who2
stored procedure to get current blocked and blocking processes on a SQL Server instance. Typically you'd run this alongside a SQL Profiler instance to find a blocking process and look at the most recent command that spid issued in profiler.
Render HTML to an image
May I recommend dom-to-image library, that was written solely to address this problem (I'm the maintainer).
Here is how you use it (some more here):
var node = document.getElementById('my-node');
domtoimage.toPng(node)
.then (function (dataUrl) {
var img = new Image();
img.src = dataUrl;
document.appendChild(img);
})
.catch(function (error) {
console.error('oops, something went wrong!', error);
});
Removing the fragment identifier from AngularJS urls (# symbol)
You can tweak the html5mode but that is only functional for links included in html anchors of your page and how the url looks like in the browser address bar. Attempting to request a subpage without the hashtag (with or without html5mode) from anywhere outside the page will result in a 404 error. For example, the following CURL request will result in a page not found error, irrespective of html5mode:
$ curl http://foo.bar/phones
although the following will return the root/home page:
$ curl http://foo.bar/#/phones
The reason for this is that anything after the hashtag is stripped off before the request arrives at the server. So a request for http://foo.bar/#/portfolio
arrives at the server as a request for http://foo.bar
. The server will respond with a 200 OK response (presumably) for http://foo.bar
and the agent/client will process the rest.
So in cases that you want to share a url with others, you have no option but to include the hashtag.
How to read a file in reverse order?
Always use with
when working with files as it handles everything for you:
with open('filename', 'r') as f:
for line in reversed(f.readlines()):
print line
Or in Python 3:
with open('filename', 'r') as f:
for line in reversed(list(f.readlines())):
print(line)
How can I print message in Makefile?
It's not clear what you want, or whether you want this trick to work with different targets, or whether you've defined these targets elsewhere, or what version of Make you're using, but what the heck, I'll go out on a limb:
ifeq (yes, ${TEST})
CXXFLAGS := ${CXXFLAGS} -DDESKTOP_TEST
test:
$(info ************ TEST VERSION ************)
else
release:
$(info ************ RELEASE VERSIOIN **********)
endif
Submitting the value of a disabled input field
I wanna Disable an Input Field on a
form and when i submit the form the
values from the disabled form is not
submitted.
Use Case: i am trying to get Lat Lng
from Google Map and wanna Display it..
but dont want the user to edit it.
You can use the readonly
property in your input field
<input type="text" readonly="readonly" />
Why can't C# interfaces contain fields?
Others have given the 'Why', so I'll just add that your interface can define a Control; if you wrap it in a property:
public interface IView {
Control Year { get; }
}
public Form : IView {
public Control Year { get { return uxYear; } } //numeric text box or whatever
}
How to stop/shut down an elasticsearch node?
Considering you have 3 nodes.
Prepare your cluster
export ES_HOST=localhost:9200
# Disable shard allocation
curl -X PUT "$ES_HOST/_cluster/settings" -H 'Content-Type: application/json' -d'
{
"persistent": {
"cluster.routing.allocation.enable": "none"
}
}
'
# Stop non-essential indexing and perform a synced flush
curl -X POST "$ES_HOST/_flush/synced"
Stop elasticsearch service in each node
# check nodes
export ES_HOST=localhost:9200
curl -X GET "$ES_HOST/_cat/nodes"
# node 1
systemctl stop elasticsearch.service
# node 2
systemctl stop elasticsearch.service
# node 3
systemctl stop elasticsearch.service
Restarting cluster again
# start
systemctl start elasticsearch.service
# Reenable shard allocation once the node has joined the cluster
curl -X PUT "$ES_HOST/_cluster/settings" -H 'Content-Type: application/json' -d'
{
"persistent": {
"cluster.routing.allocation.enable": null
}
}
'
Tested on Elasticseach 6.5
Source:
- https://www.elastic.co/guide/en/elasticsearch/reference/6.5/stopping-elasticsearch.html
- https://www.elastic.co/guide/en/elasticsearch/reference/6.5/rolling-upgrades.html
How can I color Python logging output?
Install the colorlog package, you can use colors in your log messages immediately:
- Obtain a
logger
instance, exactly as you would normally do.
- Set the logging level. You can also use the constants like
DEBUG
and INFO
from the logging module directly.
- Set the message formatter to be the
ColoredFormatter
provided
by the colorlog
library.
import colorlog
logger = colorlog.getLogger()
logger.setLevel(colorlog.colorlog.logging.DEBUG)
handler = colorlog.StreamHandler()
handler.setFormatter(colorlog.ColoredFormatter())
logger.addHandler(handler)
logger.debug("Debug message")
logger.info("Information message")
logger.warning("Warning message")
logger.error("Error message")
logger.critical("Critical message")
output:
UPDATE: extra info
Just update ColoredFormatter
:
handler.setFormatter(colorlog.ColoredFormatter('%(log_color)s [%(asctime)s] %(levelname)s [%(filename)s.%(funcName)s:%(lineno)d] %(message)s', datefmt='%a, %d %b %Y %H:%M:%S'))
output:
Package:
pip install colorlog
output:
Collecting colorlog
Downloading colorlog-4.6.2-py2.py3-none-any.whl (10.0 kB)
Installing collected packages: colorlog
Successfully installed colorlog-4.6.2
How to download file from database/folder using php
I have changed to your code with little modification will works well.
Here is the code:
butangDonload.php
<?php
$file = "logo_ldg.png"; //Let say If I put the file name Bang.png
echo "<a href='download1.php?nama=".$file."'>download</a> ";
?>
download.php
<?php
$name= $_GET['nama'];
header('Content-Description: File Transfer');
header('Content-Type: application/force-download');
header("Content-Disposition: attachment; filename=\"" . basename($name) . "\";");
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
header('Content-Length: ' . filesize($name));
ob_clean();
flush();
readfile("your_file_path/".$name); //showing the path to the server where the file is to be download
exit;
?>
Here you need to show the path from where the file to be download.
i.e. will just give the file name but need to give the file path for reading that file. So, it should be replaced by
I have tested by using your code and modifying also will works.
How do I parse a string into a number with Dart?
void main(){
var x = "4";
int number = int.parse(x);//STRING to INT
var y = "4.6";
double doubleNum = double.parse(y);//STRING to DOUBLE
var z = 55;
String myStr = z.toString();//INT to STRING
}
int.parse() and double.parse() can throw an error when it couldn't parse the String
Action Bar's onClick listener for the Home button
You need to explicitly enable the home action if running on ICS. From the docs:
Note: If you're using the icon to navigate to the home activity, beware that
beginning with Android 4.0 (API level 14), you must
explicitly enable the icon as an action item by calling
setHomeButtonEnabled(true) (in previous versions, the icon was enabled
as an action item by default).
Understanding the Rails Authenticity Token
The authenticity token is used to prevent Cross-Site Request Forgery attacks (CSRF). To understand the authenticity token, you must first understand CSRF attacks.
CSRF
Suppose that you are the author of bank.com
. You have a form on your site that is used to transfer money to a different account with a GET request:
A hacker could just send an HTTP request to the server saying GET /transfer?amount=$1000000&account-to=999999
, right?
Wrong. The hackers attack won't work. The server will basically think?
Huh? Who is this guy trying to initiate a transfer. It's not the owner of the account, that's for sure.
How does the server know this? Because there's no session_id
cookie authenticating the requester.
When you sign in with your username and password, the server sets a session_id
cookie on your browser. That way, you don't have to authenticate each request with your username and password. When your browser sends the session_id
cookie, the server knows:
Oh, that's John Doe. He signed in successfully 2.5 minutes ago. He's good to go.
A hacker might think:
Hmm. A normal HTTP request won't work, but if I could get my hand on that session_id
cookie, I'd be golden.
The users browser has a bunch of cookies set for the bank.com
domain. Every time the user makes a request to the bank.com
domain, all of the cookies get sent along. Including the session_id
cookie.
So if a hacker could get you to make the GET request that transfers money into his account, he'd be successful. How could he trick you into doing so?
With Cross Site Request Forgery.
It's pretty simply, actually. The hacker could just get you to visit his website. On his website, he could have the following image tag:
<img src="http://bank.com/transfer?amount=$1000000&account-to=999999">
When the users browser comes across that image tag, it'll be making a GET request to that url. And since the request comes from his browser, it'll send with it all of the cookies associated with bank.com
. If the user had recently signed in to bank.com
... the session_id
cookie will be set, and the server will think that the user meant to transfer $1,000,000 to account 999999!
Well, just don't visit dangerous sites and you'll be fine.
That isn't enough. What if someone posts that image to Facebook and it appears on your wall? What if it's injected into a site you're visiting with a XSS attack?
It's not so bad. Only GET requests are vulnerable.
Not true. A form that sends a POST request can be dynamically generated. Here's the example from the Rails Guide on Security:
<a href="http://www.harmless.com/" onclick="
var f = document.createElement('form');
f.style.display = 'none';
this.parentNode.appendChild(f);
f.method = 'POST';
f.action = 'http://www.example.com/account/destroy';
f.submit();
return false;">To the harmless survey</a>
Authenticity Token
When your ApplicationController
has this:
protect_from_forgery with: :exception
This:
<%= form_tag do %>
Form contents
<% end %>
Is compiled into this:
<form accept-charset="UTF-8" action="/" method="post">
<input name="utf8" type="hidden" value="✓" />
<input name="authenticity_token" type="hidden" value="J7CBxfHalt49OSHp27hblqK20c9PgwJ108nDHX/8Cts=" />
Form contents
</form>
In particular, the following is generated:
<input name="authenticity_token" type="hidden" value="J7CBxfHalt49OSHp27hblqK20c9PgwJ108nDHX/8Cts=" />
To protect against CSRF attacks, if Rails doesn't see the authenticity token sent along with a request, it won't consider the request safe.
How is an attacker supposed to know what this token is? A different value is generated randomly each time the form is generated:
A Cross Site Scripting (XSS) attack - that's how. But that's a different vulnerability for a different day.
#1062 - Duplicate entry for key 'PRIMARY'
The DB I was importing had a conflict during the import due to the presence of a column both autoincrement and primary key.
The problem was that in the .sql file the table was chopped into multiple "INSERT INTO" and during the import these queries were executed all together.
MY SOLUTION was to deselect the "Run multiple queries in each execution" on Navicat and it worked perfectly
What column type/length should I use for storing a Bcrypt hashed password in a Database?
A Bcrypt hash can be stored in a BINARY(40)
column.
BINARY(60)
, as the other answers suggest, is the easiest and most natural choice, but if you want to maximize storage efficiency, you can save 20 bytes by losslessly deconstructing the hash. I've documented this more thoroughly on GitHub: https://github.com/ademarre/binary-mcf
Bcrypt hashes follow a structure referred to as modular crypt format (MCF). Binary MCF (BMCF) decodes these textual hash representations to a more compact binary structure. In the case of Bcrypt, the resulting binary hash is 40 bytes.
Gumbo did a nice job of explaining the four components of a Bcrypt MCF hash:
$<id>$<cost>$<salt><digest>
Decoding to BMCF goes like this:
$<id>$
can be represented in 3 bits.
<cost>$
, 04-31, can be represented in 5 bits. Put these together for 1 byte.
- The 22-character salt is a (non-standard) base-64 representation of 128 bits. Base-64 decoding yields 16 bytes.
- The 31-character hash digest can be base-64 decoded to 23 bytes.
- Put it all together for 40 bytes:
1 + 16 + 23
You can read more at the link above, or examine my PHP implementation, also on GitHub.
Convert Java String to sql.Timestamp
If you get time as string in format such as 1441963946053 you simply could do something as following:
//String timestamp;
Long miliseconds = Long.valueOf(timestamp);
Timestamp ti = new Timestamp(miliseconds);
How to get hex color value rather than RGB value?
Same answer like @Jim F answer but ES6 syntax , so, less instructions :
const rgb2hex = (rgb) => {
if (rgb.search("rgb") === -1) return rgb;
rgb = rgb.match(/^rgba?\((\d+),\s*(\d+),\s*(\d+)(?:,\s*(\d+))?\)$/);
const hex = (x) => ("0" + parseInt(x).toString(16)).slice(-2);
return "#" + hex(rgb[1]) + hex(rgb[2]) + hex(rgb[3]);
};
CodeIgniter: Load controller within controller
With the following code you can load the controller classes and execute the methods.
This code was written for codeigniter 2.1
First add a new file MY_Loader.php
in your application/core directory. Add the following code to your newly created MY_Loader.php
file:
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
// written by AJ [email protected]
class MY_Loader extends CI_Loader
{
protected $_my_controller_paths = array();
protected $_my_controllers = array();
public function __construct()
{
parent::__construct();
$this->_my_controller_paths = array(APPPATH);
}
public function controller($controller, $name = '', $db_conn = FALSE)
{
if (is_array($controller))
{
foreach ($controller as $babe)
{
$this->controller($babe);
}
return;
}
if ($controller == '')
{
return;
}
$path = '';
// Is the controller in a sub-folder? If so, parse out the filename and path.
if (($last_slash = strrpos($controller, '/')) !== FALSE)
{
// The path is in front of the last slash
$path = substr($controller, 0, $last_slash + 1);
// And the controller name behind it
$controller = substr($controller, $last_slash + 1);
}
if ($name == '')
{
$name = $controller;
}
if (in_array($name, $this->_my_controllers, TRUE))
{
return;
}
$CI =& get_instance();
if (isset($CI->$name))
{
show_error('The controller name you are loading is the name of a resource that is already being used: '.$name);
}
$controller = strtolower($controller);
foreach ($this->_my_controller_paths as $mod_path)
{
if ( ! file_exists($mod_path.'controllers/'.$path.$controller.'.php'))
{
continue;
}
if ($db_conn !== FALSE AND ! class_exists('CI_DB'))
{
if ($db_conn === TRUE)
{
$db_conn = '';
}
$CI->load->database($db_conn, FALSE, TRUE);
}
if ( ! class_exists('CI_Controller'))
{
load_class('Controller', 'core');
}
require_once($mod_path.'controllers/'.$path.$controller.'.php');
$controller = ucfirst($controller);
$CI->$name = new $controller();
$this->_my_controllers[] = $name;
return;
}
// couldn't find the controller
show_error('Unable to locate the controller you have specified: '.$controller);
}
}
Now you can load all the controllers in your application/controllers directory.
for example:
load the controller class Invoice and execute the function test()
$this->load->controller('invoice','invoice_controller');
$this->invoice_controller->test();
or when the class is within a dir
$this->load->controller('/dir/invoice','invoice_controller');
$this->invoice_controller->test();
It just works the same like loading a model
Saving awk output to variable
I think the $() syntax is easier to read...
variable=$(ps -ef | grep "port 10 -" | grep -v "grep port 10 -"| awk '{printf "%s", $12}')
But the real issue is probably that $12
should not be qouted with ""
Edited since the question was changed, This returns valid data, but it is not clear what the expected output of ps -ef
is and what is expected in variable.
Auto-fit TextView for Android
Thanks to MartinH's simple fix here, this code also takes care of android:drawableLeft
, android:drawableRight
, android:drawableTop
and android:drawableBottom
tags.
My answer here should make you happy Auto Scale TextView Text to Fit within Bounds
I have modified your test case:
@Override
protected void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final ViewGroup container = (ViewGroup) findViewById(R.id.container);
findViewById(R.id.button1).setOnClickListener(new OnClickListener() {
@Override
public void onClick(final View v) {
container.removeAllViews();
final int maxWidth = container.getWidth();
final int maxHeight = container.getHeight();
final AutoResizeTextView fontFitTextView = new AutoResizeTextView(MainActivity.this);
final int width = _random.nextInt(maxWidth) + 1;
final int height = _random.nextInt(maxHeight) + 1;
fontFitTextView.setLayoutParams(new FrameLayout.LayoutParams(
width, height));
int maxLines = _random.nextInt(4) + 1;
fontFitTextView.setMaxLines(maxLines);
fontFitTextView.setTextSize(500);// max size
fontFitTextView.enableSizeCache(false);
fontFitTextView.setBackgroundColor(0xff00ff00);
final String text = getRandomText();
fontFitTextView.setText(text);
container.addView(fontFitTextView);
Log.d("DEBUG", "width:" + width + " height:" + height
+ " text:" + text + " maxLines:" + maxLines);
}
});
}
I am posting code here at per android developer's request:
Final effect:
Sample Layout file:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:padding="16dp" >
<com.vj.widgets.AutoResizeTextView
android:layout_width="match_parent"
android:layout_height="100dp"
android:ellipsize="none"
android:maxLines="2"
android:text="Auto Resized Text, max 2 lines"
android:textSize="100sp" /> <!-- maximum size -->
<com.vj.widgets.AutoResizeTextView
android:layout_width="match_parent"
android:layout_height="100dp"
android:ellipsize="none"
android:gravity="center"
android:maxLines="1"
android:text="Auto Resized Text, max 1 line"
android:textSize="100sp" /> <!-- maximum size -->
<com.vj.widgets.AutoResizeTextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Auto Resized Text"
android:textSize="500sp" /> <!-- maximum size -->
</LinearLayout>
And the Java code:
import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.RectF;
import android.os.Build;
import android.text.Layout.Alignment;
import android.text.StaticLayout;
import android.text.TextPaint;
import android.util.AttributeSet;
import android.util.SparseIntArray;
import android.util.TypedValue;
import android.widget.TextView;
public class AutoResizeTextView extends TextView {
private interface SizeTester {
/**
*
* @param suggestedSize
* Size of text to be tested
* @param availableSpace
* available space in which text must fit
* @return an integer < 0 if after applying {@code suggestedSize} to
* text, it takes less space than {@code availableSpace}, > 0
* otherwise
*/
public int onTestSize(int suggestedSize, RectF availableSpace);
}
private RectF mTextRect = new RectF();
private RectF mAvailableSpaceRect;
private SparseIntArray mTextCachedSizes;
private TextPaint mPaint;
private float mMaxTextSize;
private float mSpacingMult = 1.0f;
private float mSpacingAdd = 0.0f;
private float mMinTextSize = 20;
private int mWidthLimit;
private static final int NO_LINE_LIMIT = -1;
private int mMaxLines;
private boolean mEnableSizeCache = true;
private boolean mInitializedDimens;
public AutoResizeTextView(Context context) {
super(context);
initialize();
}
public AutoResizeTextView(Context context, AttributeSet attrs) {
super(context, attrs);
initialize();
}
public AutoResizeTextView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initialize();
}
private void initialize() {
mPaint = new TextPaint(getPaint());
mMaxTextSize = getTextSize();
mAvailableSpaceRect = new RectF();
mTextCachedSizes = new SparseIntArray();
if (mMaxLines == 0) {
// no value was assigned during construction
mMaxLines = NO_LINE_LIMIT;
}
}
@Override
public void setTextSize(float size) {
mMaxTextSize = size;
mTextCachedSizes.clear();
adjustTextSize();
}
@Override
public void setMaxLines(int maxlines) {
super.setMaxLines(maxlines);
mMaxLines = maxlines;
adjustTextSize();
}
public int getMaxLines() {
return mMaxLines;
}
@Override
public void setSingleLine() {
super.setSingleLine();
mMaxLines = 1;
adjustTextSize();
}
@Override
public void setSingleLine(boolean singleLine) {
super.setSingleLine(singleLine);
if (singleLine) {
mMaxLines = 1;
} else {
mMaxLines = NO_LINE_LIMIT;
}
adjustTextSize();
}
@Override
public void setLines(int lines) {
super.setLines(lines);
mMaxLines = lines;
adjustTextSize();
}
@Override
public void setTextSize(int unit, float size) {
Context c = getContext();
Resources r;
if (c == null)
r = Resources.getSystem();
else
r = c.getResources();
mMaxTextSize = TypedValue.applyDimension(unit, size,
r.getDisplayMetrics());
mTextCachedSizes.clear();
adjustTextSize();
}
@Override
public void setLineSpacing(float add, float mult) {
super.setLineSpacing(add, mult);
mSpacingMult = mult;
mSpacingAdd = add;
}
/**
* Set the lower text size limit and invalidate the view
*
* @param minTextSize
*/
public void setMinTextSize(float minTextSize) {
mMinTextSize = minTextSize;
adjustTextSize();
}
private void adjustTextSize() {
if (!mInitializedDimens) {
return;
}
int startSize = (int) mMinTextSize;
int heightLimit = getMeasuredHeight() - getCompoundPaddingBottom()
- getCompoundPaddingTop();
mWidthLimit = getMeasuredWidth() - getCompoundPaddingLeft()
- getCompoundPaddingRight();
mAvailableSpaceRect.right = mWidthLimit;
mAvailableSpaceRect.bottom = heightLimit;
super.setTextSize(
TypedValue.COMPLEX_UNIT_PX,
efficientTextSizeSearch(startSize, (int) mMaxTextSize,
mSizeTester, mAvailableSpaceRect));
}
private final SizeTester mSizeTester = new SizeTester() {
@TargetApi(Build.VERSION_CODES.JELLY_BEAN)
@Override
public int onTestSize(int suggestedSize, RectF availableSPace) {
mPaint.setTextSize(suggestedSize);
String text = getText().toString();
boolean singleline = getMaxLines() == 1;
if (singleline) {
mTextRect.bottom = mPaint.getFontSpacing();
mTextRect.right = mPaint.measureText(text);
} else {
StaticLayout layout = new StaticLayout(text, mPaint,
mWidthLimit, Alignment.ALIGN_NORMAL, mSpacingMult,
mSpacingAdd, true);
// Return early if we have more lines
if (getMaxLines() != NO_LINE_LIMIT
&& layout.getLineCount() > getMaxLines()) {
return 1;
}
mTextRect.bottom = layout.getHeight();
int maxWidth = -1;
for (int i = 0; i < layout.getLineCount(); i++) {
if (maxWidth < layout.getLineWidth(i)) {
maxWidth = (int) layout.getLineWidth(i);
}
}
mTextRect.right = maxWidth;
}
mTextRect.offsetTo(0, 0);
if (availableSPace.contains(mTextRect)) {
// May be too small, don't worry we will find the best match
return -1;
} else {
// too big
return 1;
}
}
};
/**
* Enables or disables size caching, enabling it will improve performance
* where you are animating a value inside TextView. This stores the font
* size against getText().length() Be careful though while enabling it as 0
* takes more space than 1 on some fonts and so on.
*
* @param enable
* Enable font size caching
*/
public void enableSizeCache(boolean enable) {
mEnableSizeCache = enable;
mTextCachedSizes.clear();
adjustTextSize(getText().toString());
}
private int efficientTextSizeSearch(int start, int end,
SizeTester sizeTester, RectF availableSpace) {
if (!mEnableSizeCache) {
return binarySearch(start, end, sizeTester, availableSpace);
}
int key = getText().toString().length();
int size = mTextCachedSizes.get(key);
if (size != 0) {
return size;
}
size = binarySearch(start, end, sizeTester, availableSpace);
mTextCachedSizes.put(key, size);
return size;
}
private static int binarySearch(int start, int end, SizeTester sizeTester,
RectF availableSpace) {
int lastBest = start;
int lo = start;
int hi = end - 1;
int mid = 0;
while (lo <= hi) {
mid = (lo + hi) >>> 1;
int midValCmp = sizeTester.onTestSize(mid, availableSpace);
if (midValCmp < 0) {
lastBest = lo;
lo = mid + 1;
} else if (midValCmp > 0) {
hi = mid - 1;
lastBest = hi;
} else {
return mid;
}
}
// Make sure to return the last best.
// This is what should always be returned.
return lastBest;
}
@Override
protected void onTextChanged(final CharSequence text, final int start,
final int before, final int after) {
super.onTextChanged(text, start, before, after);
adjustTextSize();
}
@Override
protected void onSizeChanged(int width, int height, int oldwidth,
int oldheight) {
mInitializedDimens = true;
mTextCachedSizes.clear();
super.onSizeChanged(width, height, oldwidth, oldheight);
if (width != oldwidth || height != oldheight) {
adjustTextSize();
}
}
}
Warning:
Beware of this resolved bug in Android 3.1 (Honeycomb) though.
Create a string of variable length, filled with a repeated character
For Evergreen browsers, this will build a staircase based on an incoming character and the number of stairs to build.
function StairCase(character, input) {
let i = 0;
while (i < input) {
const spaces = " ".repeat(input - (i+1));
const hashes = character.repeat(i + 1);
console.log(spaces + hashes);
i++;
}
}
//Implement
//Refresh the console
console.clear();
StairCase("#",6);
You can also add a polyfill for Repeat for older browsers
if (!String.prototype.repeat) {
String.prototype.repeat = function(count) {
'use strict';
if (this == null) {
throw new TypeError('can\'t convert ' + this + ' to object');
}
var str = '' + this;
count = +count;
if (count != count) {
count = 0;
}
if (count < 0) {
throw new RangeError('repeat count must be non-negative');
}
if (count == Infinity) {
throw new RangeError('repeat count must be less than infinity');
}
count = Math.floor(count);
if (str.length == 0 || count == 0) {
return '';
}
// Ensuring count is a 31-bit integer allows us to heavily optimize the
// main part. But anyway, most current (August 2014) browsers can't handle
// strings 1 << 28 chars or longer, so:
if (str.length * count >= 1 << 28) {
throw new RangeError('repeat count must not overflow maximum string size');
}
var rpt = '';
for (;;) {
if ((count & 1) == 1) {
rpt += str;
}
count >>>= 1;
if (count == 0) {
break;
}
str += str;
}
// Could we try:
// return Array(count + 1).join(this);
return rpt;
}
}
How do you Encrypt and Decrypt a PHP String?
For Laravel framework
If you are using Laravel framework then it's more easy to encrypt and decrypt with internal functions.
$string = 'Some text to be encrypted';
$encrypted = \Illuminate\Support\Facades\Crypt::encrypt($string);
$decrypted_string = \Illuminate\Support\Facades\Crypt::decrypt($encrypted);
var_dump($string);
var_dump($encrypted);
var_dump($decrypted_string);
Note: Be sure to set a 16, 24, or 32 character random string in the
key option of the config/app.php file. Otherwise, encrypted values
will not be secure.
How to use <DllImport> in VB.NET?
You have to add Imports System.Runtime.InteropServices
to the top of your source file.
Alternatively, you can fully qualify attribute name:
<System.Runtime.InteropService.DllImport("user32.dll", _
SetLastError:=True, CharSet:=CharSet.Auto)> _
Get Memory Usage in Android
I use this function to calculate cpu usage. Hope it can help you.
private float readUsage() {
try {
RandomAccessFile reader = new RandomAccessFile("/proc/stat", "r");
String load = reader.readLine();
String[] toks = load.split(" +"); // Split on one or more spaces
long idle1 = Long.parseLong(toks[4]);
long cpu1 = Long.parseLong(toks[2]) + Long.parseLong(toks[3]) + Long.parseLong(toks[5])
+ Long.parseLong(toks[6]) + Long.parseLong(toks[7]) + Long.parseLong(toks[8]);
try {
Thread.sleep(360);
} catch (Exception e) {}
reader.seek(0);
load = reader.readLine();
reader.close();
toks = load.split(" +");
long idle2 = Long.parseLong(toks[4]);
long cpu2 = Long.parseLong(toks[2]) + Long.parseLong(toks[3]) + Long.parseLong(toks[5])
+ Long.parseLong(toks[6]) + Long.parseLong(toks[7]) + Long.parseLong(toks[8]);
return (float)(cpu2 - cpu1) / ((cpu2 + idle2) - (cpu1 + idle1));
} catch (IOException ex) {
ex.printStackTrace();
}
return 0;
}
Python Create unix timestamp five minutes in the future
Now in Python >= 3.3 you can just call the timestamp() method to get the timestamp as a float.
import datetime
current_time = datetime.datetime.now(datetime.timezone.utc)
unix_timestamp = current_time.timestamp() # works if Python >= 3.3
unix_timestamp_plus_5_min = unix_timestamp + (5 * 60) # 5 min * 60 seconds
How to display pandas DataFrame of floats using a format string for columns?
If you do not want to change the display format permanently, and perhaps apply a new format later on, I personally favour the use of a resource manager (the with
statement in Python). In your case you could do something like this:
with pd.option_context('display.float_format', '${:0.2f}'.format):
print(df)
If you happen to need a different format further down in your code, you can change it by varying just the format in the snippet above.
mysqli::query(): Couldn't fetch mysqli
Probably somewhere you have DBconnection->close();
and then some queries try to execute .
Hint: It's sometimes mistake to insert ...->close();
in __destruct()
(because __destruct
is event, after which there will be a need for execution of queries)
Change a web.config programmatically with C# (.NET)
Since web.config file is xml file you can open web.config using xmldocument class. Get the node from that xml file that you want to update and then save xml file.
here is URL that explains in more detail how you can update web.config file programmatically.
http://patelshailesh.com/index.php/update-web-config-programmatically
Note: if you make any changes to web.config, ASP.NET detects that changes and it will reload your application(recycle application pool) and effect of that is data kept in Session, Application, and Cache will be lost (assuming session state is InProc and not using a state server or database).
How to detect reliably Mac OS X, iOS, Linux, Windows in C preprocessor?
As Jake points out, TARGET_IPHONE_SIMULATOR
is a subset of TARGET_OS_IPHONE
.
Also, TARGET_OS_IPHONE
is a subset of TARGET_OS_MAC
.
So a better approach might be:
#ifdef _WIN64
//define something for Windows (64-bit)
#elif _WIN32
//define something for Windows (32-bit)
#elif __APPLE__
#include "TargetConditionals.h"
#if TARGET_OS_IPHONE && TARGET_IPHONE_SIMULATOR
// define something for simulator
#elif TARGET_OS_IPHONE
// define something for iphone
#else
#define TARGET_OS_OSX 1
// define something for OSX
#endif
#elif __linux
// linux
#elif __unix // all unices not caught above
// Unix
#elif __posix
// POSIX
#endif
Attach parameter to button.addTarget action in Swift
Swift 4.2
Result:
testButton.on(.touchUpInside) { (sender, event) in
// You can use any reference initialized before the code block here
// You can access self by adding [weak self] before (sender, event)
// You can then either make self strong by using a guard statement or use a optional operator (?)
print("user did press test button")
}
In the file UIButton+Events.swift
I've created an extension method for UIButton
that binds a UIControl.Event
to a completion handler called EventHandler
:
import UIKit
fileprivate var bindedEvents: [UIButton:EventBinder] = [:]
fileprivate class EventBinder {
let event: UIControl.Event
let button: UIButton
let handler: UIButton.EventHandler
let selector: Selector
required init(
_ event: UIControl.Event,
on button: UIButton,
withHandler handler: @escaping UIButton.EventHandler
) {
self.event = event
self.button = button
self.handler = handler
self.selector = #selector(performEvent(on:ofType:))
button.addTarget(self, action: self.selector, for: event)
}
deinit {
button.removeTarget(self, action: selector, for: event)
if let index = bindedEvents.index(forKey: button) {
bindedEvents.remove(at: index)
}
}
}
private extension EventBinder {
@objc func performEvent(on sender: UIButton, ofType event: UIControl.Event) {
handler(sender, event)
}
}
extension UIButton {
typealias EventHandler = (UIButton, UIControl.Event) -> Void
func on(_ event: UIControl.Event, handler: @escaping EventHandler) {
bindedEvents[self] = EventBinder(event, on: self, withHandler: handler)
}
}
The reason why I used a custom class for binding the event is to be able to dispose the reference later when the button is deintialised. This will prevent a possible memory leak from occurring. This wasn't possible within the UIButton
its extension, because I'm not allowed to implement a property nor the deinit
method.
Scripting SQL Server permissions
Our version:
SET NOCOUNT ON
DECLARE @message NVARCHAR(MAX)
-- GENERATE LOGINS CREATE SCRIPT
USE [master]
-- creating accessory procedure
IF EXISTS (SELECT 1 FROM sys.objects WHERE object_id = OBJECT_ID(N'sp_hexadecimal') AND type IN ( N'P', N'PC' ))
DROP PROCEDURE [dbo].[sp_hexadecimal]
EXEC('
CREATE PROCEDURE [dbo].[sp_hexadecimal]
@binvalue varbinary(256),
@hexvalue varchar (514) OUTPUT
AS
DECLARE @charvalue varchar (514)
DECLARE @i int
DECLARE @length int
DECLARE @hexstring char(16)
SELECT @charvalue = ''0x''
SELECT @i = 1
SELECT @length = DATALENGTH (@binvalue)
SELECT @hexstring = ''0123456789ABCDEF''
WHILE (@i <= @length)
BEGIN
DECLARE @tempint int
DECLARE @firstint int
DECLARE @secondint int
SELECT @tempint = CONVERT(int, SUBSTRING(@binvalue,@i,1))
SELECT @firstint = FLOOR(@tempint/16)
SELECT @secondint = @tempint - (@firstint*16)
SELECT @charvalue = @charvalue +
SUBSTRING(@hexstring, @firstint+1, 1) +
SUBSTRING(@hexstring, @secondint+1, 1)
SELECT @i = @i + 1
END
SELECT @hexvalue = @charvalue')
SET @message = '-- CREATE LOGINS' + CHAR(13) + CHAR(13) +'USE [master]' + CHAR(13)
DECLARE @name sysname
DECLARE @type varchar (1)
DECLARE @hasaccess int
DECLARE @denylogin int
DECLARE @is_disabled int
DECLARE @PWD_varbinary varbinary (256)
DECLARE @PWD_string varchar (514)
DECLARE @SID_varbinary varbinary (85)
DECLARE @SID_string varchar (514)
DECLARE @tmpstr NVARCHAR(MAX)
DECLARE @is_policy_checked varchar (3)
DECLARE @is_expiration_checked varchar (3)
DECLARE @defaultdb sysname
DECLARE login_curs CURSOR FOR
SELECT p.sid, p.name, p.type, p.is_disabled, p.default_database_name, l.hasaccess, l.denylogin FROM
sys.server_principals p LEFT JOIN sys.syslogins l
ON ( l.name = p.name ) WHERE p.type IN ( 'S', 'G', 'U' ) AND p.name <> 'sa'
OPEN login_curs
FETCH NEXT FROM login_curs INTO @SID_varbinary, @name, @type, @is_disabled, @defaultdb, @hasaccess, @denylogin
IF (@@fetch_status = -1)
BEGIN
PRINT 'No login(s) found.'
CLOSE login_curs
DEALLOCATE login_curs
END
WHILE (@@fetch_status <> -1)
BEGIN
IF (@@fetch_status <> -2)
BEGIN
IF (@type IN ( 'G', 'U'))
BEGIN -- NT authenticated account/group
SET @tmpstr = 'IF NOT EXISTS (SELECT loginname FROM master.dbo.syslogins WHERE name = ''' + @name + ''' AND dbname = ''' + @defaultdb + ''')' + CHAR(13) +
'BEGIN TRY' + CHAR(13) +
' CREATE LOGIN ' + QUOTENAME( @name ) + ' FROM WINDOWS WITH DEFAULT_DATABASE = [' + @defaultdb + ']'
END
ELSE BEGIN -- SQL Server authentication
-- obtain password and sid
SET @PWD_varbinary = CAST( LOGINPROPERTY( @name, 'PasswordHash' ) AS varbinary (256) )
EXEC sp_hexadecimal @PWD_varbinary, @PWD_string OUT
EXEC sp_hexadecimal @SID_varbinary,@SID_string OUT
-- obtain password policy state
SELECT @is_policy_checked = CASE is_policy_checked WHEN 1 THEN 'ON' WHEN 0 THEN 'OFF' ELSE NULL END FROM sys.sql_logins WHERE name = @name
SELECT @is_expiration_checked = CASE is_expiration_checked WHEN 1 THEN 'ON' WHEN 0 THEN 'OFF' ELSE NULL END FROM sys.sql_logins WHERE name = @name
SET @tmpstr = 'IF NOT EXISTS (SELECT loginname FROM master.dbo.syslogins WHERE name = ''' + @name + ''' AND dbname = ''' + @defaultdb + ''')' + CHAR(13) +
'BEGIN TRY' + CHAR(13) +
' CREATE LOGIN ' + QUOTENAME( @name ) + ' WITH PASSWORD = ' + @PWD_string + ' HASHED, SID = ' + @SID_string + ', DEFAULT_DATABASE = [' + @defaultdb + ']'
IF ( @is_policy_checked IS NOT NULL )
BEGIN
SET @tmpstr = @tmpstr + ', CHECK_POLICY = ' + @is_policy_checked
END
IF ( @is_expiration_checked IS NOT NULL )
BEGIN
SET @tmpstr = @tmpstr + ', CHECK_EXPIRATION = ' + @is_expiration_checked
END
END
IF (@denylogin = 1)
BEGIN -- login is denied access
SET @tmpstr = @tmpstr + '; DENY CONNECT SQL TO ' + QUOTENAME( @name )
END
ELSE IF (@hasaccess = 0)
BEGIN -- login exists but does not have access
SET @tmpstr = @tmpstr + '; REVOKE CONNECT SQL TO ' + QUOTENAME( @name )
END
IF (@is_disabled = 1)
BEGIN -- login is disabled
SET @tmpstr = @tmpstr + '; ALTER LOGIN ' + QUOTENAME( @name ) + ' DISABLE'
END
SET @tmpstr = @tmpstr + CHAR(13) + 'END TRY' + CHAR(13) + 'BEGIN CATCH' + CHAR(13) + 'END CATCH'
SET @message = @message + CHAR(13) + @tmpstr
END
FETCH NEXT FROM login_curs INTO @SID_varbinary, @name, @type, @is_disabled, @defaultdb, @hasaccess, @denylogin
END
CLOSE login_curs
DEALLOCATE login_curs
--removing accessory procedure
DROP PROCEDURE [dbo].[sp_hexadecimal]
-- GENERATE SERVER PERMISSIONS
USE [master]
DECLARE @ServerPrincipal SYSNAME
DECLARE @PrincipalType SYSNAME
DECLARE @PermissionName SYSNAME
DECLARE @StateDesc SYSNAME
SET @message = @message + CHAR(13) + CHAR(13) + '-- CREATE SERVER PERMISSIONS' + CHAR(13) + CHAR(13) +'USE [master]' + CHAR(13)
DECLARE server_permissions_curs CURSOR FOR
SELECT
[srvprin].[name] [server_principal],
[srvprin].[type_desc] [principal_type],
[srvperm].[permission_name],
[srvperm].[state_desc]
FROM [sys].[server_permissions] srvperm
INNER JOIN [sys].[server_principals] srvprin
ON [srvperm].[grantee_principal_id] = [srvprin].[principal_id]
WHERE [srvprin].[type] IN ('S', 'U', 'G') AND [srvprin].name NOT IN ('sa', 'dbo', 'information_schema', 'sys')
ORDER BY [server_principal], [permission_name];
OPEN server_permissions_curs
FETCH NEXT FROM server_permissions_curs INTO @ServerPrincipal, @PrincipalType, @PermissionName, @StateDesc
WHILE (@@fetch_status <> -1)
BEGIN
SET @message = @message + CHAR(13) + 'BEGIN TRY' + CHAR(13) +
@StateDesc + N' ' + @PermissionName + N' TO ' + QUOTENAME(@ServerPrincipal) +
+ CHAR(13) + 'END TRY' + CHAR(13) + 'BEGIN CATCH' + CHAR(13) + 'END CATCH'
FETCH NEXT FROM server_permissions_curs INTO @ServerPrincipal, @PrincipalType, @PermissionName, @StateDesc
END
CLOSE server_permissions_curs
DEALLOCATE server_permissions_curs
--GENERATE USERS AND PERMISSION SCRIPT FOR EVERY DATABASE
SET @message = @message + CHAR(13) + CHAR(13) + N'--ENUMERATE DATABASES'
DECLARE @databases TABLE (
DatabaseName SYSNAME,
DatabaseSize INT,
Remarks SYSNAME NULL
)
INSERT INTO
@databases EXEC sp_databases
DECLARE @DatabaseName SYSNAME
DECLARE database_curs CURSOR FOR
SELECT DatabaseName FROM @databases WHERE DatabaseName IN (N'${DatabaseName}')
OPEN database_curs
FETCH NEXT FROM database_curs INTO @DatabaseName
WHILE (@@fetch_status <> -1)
BEGIN
SET @tmpStr =
N'USE ' + QUOTENAME(@DatabaseName) + '
DECLARE @tmpstr NVARCHAR(MAX)
SET @messageOut = CHAR(13) + CHAR(13) + ''USE ' + QUOTENAME(@DatabaseName) + ''' + CHAR(13)
-- GENERATE USERS SCRIPT
SET @messageOut = @messageOut + CHAR(13) + ''-- CREATE USERS '' + CHAR(13)
DECLARE @users TABLE (
UserName SYSNAME Null,
RoleName SYSNAME Null,
LoginName SYSNAME Null,
DefDBName SYSNAME Null,
DefSchemaName SYSNAME Null,
UserID INT Null,
[SID] varbinary(85) Null
)
INSERT INTO
@users EXEC sp_helpuser
DECLARE @UserName SYSNAME
DECLARE @LoginName SYSNAME
DECLARE @DefSchemaName SYSNAME
DECLARE user_curs CURSOR FOR
SELECT UserName, LoginName, DefSchemaName FROM @users
OPEN user_curs
FETCH NEXT FROM user_curs INTO @UserName, @LoginName, @DefSchemaName
WHILE (@@fetch_status <> -1)
BEGIN
SET @messageOut = @messageOut + CHAR(13) +
''IF NOT EXISTS (SELECT * FROM sys.database_principals WHERE name = N''''''+ @UserName +'''''')''
+ CHAR(13) + ''BEGIN TRY'' + CHAR(13) +
'' CREATE USER '' + QUOTENAME(@UserName)
IF (@LoginName IS NOT NULL)
SET @messageOut = @messageOut + '' FOR LOGIN '' + QUOTENAME(@LoginName)
ELSE
SET @messageOut = @messageOut + '' WITHOUT LOGIN''
IF (@DefSchemaName IS NOT NULL)
SET @messageOut = @messageOut + '' WITH DEFAULT_SCHEMA = '' + QUOTENAME(@DefSchemaName)
SET @messageOut = @messageOut + CHAR(13) + ''END TRY'' + CHAR(13) + ''BEGIN CATCH'' + CHAR(13) + ''END CATCH''
FETCH NEXT FROM user_curs INTO @UserName, @LoginName, @DefSchemaName
END
CLOSE user_curs
DEALLOCATE user_curs
-- GENERATE ROLES
SET @messageOut = @messageOut + CHAR(13) + CHAR(13) + ''-- CREATE ROLES '' + CHAR(13)
SELECT @messageOut = @messageOut + CHAR(13) + ''BEGIN TRY'' + CHAR(13) +
N''EXEC sp_addrolemember N''''''+ rp.name +'''''', N''''''+ mp.name +''''''''
+ CHAR(13) + ''END TRY'' + CHAR(13) + ''BEGIN CATCH'' + CHAR(13) + ''END CATCH''
FROM sys.database_role_members drm
join sys.database_principals rp ON (drm.role_principal_id = rp.principal_id)
join sys.database_principals mp ON (drm.member_principal_id = mp.principal_id)
WHERE mp.name NOT IN (N''dbo'')
-- GENERATE PERMISSIONS
SET @messageOut = @messageOut + CHAR(13) + CHAR(13) + ''-- CREATE PERMISSIONS '' + CHAR(13)
SELECT @messageOut = @messageOut + CHAR(13) + ''BEGIN TRY'' + CHAR(13) +
'' GRANT '' + dp.permission_name collate latin1_general_cs_as +
'' ON '' + QUOTENAME(s.name) + ''.'' + QUOTENAME(o.name) + '' TO '' + QUOTENAME(dpr.name) +
+ CHAR(13) + ''END TRY'' + CHAR(13) + ''BEGIN CATCH'' + CHAR(13) + ''END CATCH''
FROM sys.database_permissions AS dp
INNER JOIN sys.objects AS o ON dp.major_id=o.object_id
INNER JOIN sys.schemas AS s ON o.schema_id = s.schema_id
INNER JOIN sys.database_principals AS dpr ON dp.grantee_principal_id=dpr.principal_id
WHERE dpr.name NOT IN (''public'',''guest'')'
EXECUTE sp_executesql @tmpStr, N'@messageOut NVARCHAR(MAX) OUTPUT', @messageOut = @tmpstr OUTPUT
SET @message = @message + @tmpStr
FETCH NEXT FROM database_curs INTO @DatabaseName
END
CLOSE database_curs
DEALLOCATE database_curs
SELECT @message
Where is jarsigner?
It's in the bin folder of your java JDK install (Java SE). If you only have the JRE installed you probably don't have it.
Testing pointers for validity (C/C++)
Addendum to the accpeted answer(s):
Assume that your pointer could hold only three values -- 0, 1 and -1 where 1 signifies a valid pointer, -1 an invalid one and 0 another invalid one. What is the probability that your pointer is NULL, all values being equally likely? 1/3. Now, take the valid case out, so for every invalid case, you have a 50:50 ratio to catch all errors. Looks good right? Scale this for a 4-byte pointer. There are 2^32 or 4294967294 possible values. Of these, only ONE value is correct, one is NULL, and you are still left with 4294967292 other invalid cases. Recalculate: you have a test for 1 out of (4294967292+ 1) invalid cases. A probability of 2.xe-10 or 0 for most practical purposes. Such is the futility of the NULL check.
Create view with primary key?
I got the error "The table/view 'dbo.vMyView' does not have a primary key defined" after I created a view in SQL server query designer. I solved the problem by using ISNULL on a column to force entity framework to use it as a primary key. You might have to restart visual studio to get the warnings to go away.
CREATE VIEW [dbo].[vMyView]
AS
SELECT ISNULL(Id, -1) AS IdPrimaryKey, Name
FROM dbo.MyTable
Django: How can I call a view function from template?
you can put the input inside a form like this:-
<script>
$(document).ready(function(){
$(document).on('click','#send', function(){
$('#hid').val(data)
document.forms["myForm"].submit();
})
})
</script>
<form id="myForm" action="/request_page url/" method="post">
<input type="hidden" id="hid" name="hid"/>
</form>
<div id="send">Send Data</div>
How to set base url for rest in spring boot?
I couldn't believe how complicate the answer to this seemingly simple question is. Here are some references:
There are many differnt things to consider:
- By setting
server.context-path=/api
in application.properties
you can configure a prefix for everything.(Its server.context-path not server.contextPath !)
- Spring Data controllers annotated with @RepositoryRestController that expose a repository as rest endpoint will use the environment variable
spring.data.rest.base-path
in application.properties
. But plain @RestController
won't take this into account. According to the spring data rest documentation there is an annotation @BasePathAwareController
that you can use for that. But I do have problems in connection with Spring-security when I try to secure such a controller. It is not found anymore.
Another workaround is a simple trick. You cannot prefix a static String in an annotation, but you can use expressions like this:
@RestController
public class PingController {
/**
* Simple is alive test
* @return <pre>{"Hello":"World"}</pre>
*/
@RequestMapping("${spring.data.rest.base-path}/_ping")
public String isAlive() {
return "{\"Hello\":\"World\"}";
}
}
Linq to SQL how to do "where [column] in (list of values)"
var filterTransNos = (from so in db.SalesOrderDetails
where ItemDescription.Contains(ItemDescription)
select new { so.TransNo }).AsEnumerable();
listreceipt = listreceipt.Where(p => filterTransNos.Any(p2 => p2.TransNo == p.TransNo)).ToList();
Pad a number with leading zeros in JavaScript
function padToFour(number) {
if (number<=9999) { number = ("000"+number).slice(-4); }
return number;
}
Something like that?
Bonus incomprehensible-but-slicker single-line ES6 version:
let padToFour = number => number <= 9999 ? `000${number}`.slice(-4) : number;
ES6isms:
let
is a block scoped variable (as opposed to var
’s functional scoping)
=>
is an arrow function that among other things replaces function
and is prepended by its parameters
- If a arrow function takes a single parameter you can omit the parentheses (hence
number =>
)
- If an arrow function body has a single line that starts with
return
you can omit the braces and the return
keyword and simply use the expression
- To get the function body down to a single line I cheated and used a ternary expression
What is the pythonic way to detect the last element in a 'for' loop?
The most simple solution coming to my mind is:
for item in data_list:
try:
print(new)
except NameError: pass
new = item
print('The last item: ' + str(new))
So we always look ahead one item by delaying the the processing one iteration. To skip doing something during the first iteration I simply catch the error.
Of course you need to think a bit, in order for the NameError
to be raised when you want it.
Also keep the `counstruct
try:
new
except NameError: pass
else:
# continue here if no error was raised
This relies that the name new wasn't previously defined. If you are paranoid you can ensure that new
doesn't exist using:
try:
del new
except NameError:
pass
Alternatively you can of course also use an if statement (if notfirst: print(new) else: notfirst = True
). But as far as I know the overhead is bigger.
Using `timeit` yields:
...: try: new = 'test'
...: except NameError: pass
...:
100000000 loops, best of 3: 16.2 ns per loop
so I expect the overhead to be unelectable.
CSS3 :unchecked pseudo-class
The way I handled this was switching the className of a label based on a condition. This way you only need one label and you can have different classes for different states... Hope that helps!
Plot logarithmic axes with matplotlib in python
You can use the Axes.set_yscale
method. That allows you to change the scale after the Axes
object is created. That would also allow you to build a control to let the user pick the scale if you needed to.
The relevant line to add is:
ax.set_yscale('log')
You can use 'linear'
to switch back to a linear scale. Here's what your code would look like:
import pylab
import matplotlib.pyplot as plt
a = [pow(10, i) for i in range(10)]
fig = plt.figure()
ax = fig.add_subplot(2, 1, 1)
line, = ax.plot(a, color='blue', lw=2)
ax.set_yscale('log')
pylab.show()