How to change the default collation of a table?
MySQL has 4 levels of collation: server, database, table, column.
If you change the collation of the server, database or table, you don't change the setting for each column, but you change the default collations.
E.g if you change the default collation of a database, each new table you create in that database will use that collation, and if you change the default collation of a table, each column you create in that table will get that collation.
How to replace a char in string with an Empty character in C#.NET
Since the other answers here, even though correct, do not explicitly address your initial doubts, I'll do it.
If you call string.Replace(char oldChar, char newChar) it will replace the occurrences of a character with another character. It is a one-for-one replacement. Because of this the length of the resulting string will be the same.
What you want is to remove the dashes, which, obviously, is not the same thing as replacing them with another character. You cannot replace it by "no character" because 1 character is always 1 character. That's why you need to use the overload that takes strings: strings can have different lengths. If you replace a string of length 1, with a string of length 0, the effect is that the dashes are gone, replaced by "nothing".
How to install requests module in Python 3.4, instead of 2.7
while installing python packages in a global environment is doable, it is a best practice to isolate the environment between projects (creating virtual environments). Otherwise, confusion between Python versions will arise, just like your problem.
The simplest method is to use venv library in the project directory:
python3 -m venv venv
Where the first venv is to call the venv package, and the second venv defines the virtual environment directory name.
Then activate the virtual environment:
source venv/bin/activate
Once the virtual environment has been activated, your pip install ... commands would not be interfered with any other Python version or pip version anymore.
For installing requests:
pip install requests
Another benefit of the virtual environment is to have a concise list of libraries needed for that specific project.
*note: commands only work on Linux and Mac OS
How to query for today's date and 7 days before data?
Query in Parado's answer is correct, if you want to use MySql too instead GETDATE() you must use (because you've tagged this question with Sql server and Mysql):
select * from tab
where DateCol between adddate(now(),-7) and now()
Finding all objects that have a given property inside a collection
JFilter http://code.google.com/p/jfilter/ suites your requirement.
JFilter is a simple and high performance open source library to query collection of Java beans.
Key features
- Support of collection (java.util.Collection, java.util.Map and Array) properties.
- Support of collection inside collection of any depth.
- Support of inner queries.
- Support of parameterized queries.
- Can filter 1 million records in few 100 ms.
- Filter ( query) is given in simple json format, it is like Mangodb queries. Following are some examples.
- { "id":{"$le":"10"}
- where object id property is less than equals to 10.
- { "id": {"$in":["0", "100"]}}
- where object id property is 0 or 100.
- {"lineItems":{"lineAmount":"1"}}
- where lineItems collection property of parameterized type has lineAmount equals to 1.
- { "$and":[{"id": "0"}, {"billingAddress":{"city":"DEL"}}]}
- where id property is 0 and billingAddress.city property is DEL.
- {"lineItems":{"taxes":{ "key":{"code":"GST"}, "value":{"$gt": "1.01"}}}}
- where lineItems collection property of parameterized type which has taxes map type property of parameteriszed type has code equals to GST value greater than 1.01.
- {'$or':[{'code':'10'},{'skus': {'$and':[{'price':{'$in':['20', '40']}}, {'code':'RedApple'}]}}]}
- Select all products where product code is 10 or sku price in 20 and 40 and sku code is "RedApple".
Preloading images with jQuery
jQuery.preloadImage=function(src,onSuccess,onError)
{
var img = new Image()
img.src=src;
var error=false;
img.onerror=function(){
error=true;
if(onError)onError.call(img);
}
if(error==false)
setTimeout(function(){
if(img.height>0&&img.width>0){
if(onSuccess)onSuccess.call(img);
return img;
} else {
setTimeout(arguments.callee,5);
}
},0);
return img;
}
jQuery.preloadImages=function(arrayOfImages){
jQuery.each(arrayOfImages,function(){
jQuery.preloadImage(this);
})
}
// example
jQuery.preloadImage(
'img/someimage.jpg',
function(){
/*complete
this.width!=0 == true
*/
},
function(){
/*error*/
}
)
Converting timestamp to time ago in PHP e.g 1 day ago, 2 days ago...
just pass the date time to this func. it would print out in time ago format for you
date_default_timezone_set('your-time-zone');
function convert($datetime){
$time=strtotime($datetime);
$diff=time()-$time;
$diff/=60;
$var1=floor($diff);
$var=$var1<=1 ? 'min' : 'mins';
if($diff>=60){
$diff/=60;
$var1=floor($diff);
$var=$var1<=1 ? 'hr' : 'hrs';
if($diff>=24){$diff/=24;$var1=floor($diff);$var=$var1<=1 ? 'day' : 'days';
if($diff>=30.4375){$diff/=30.4375;$var1=floor($diff);$var=$var1<=1 ? 'month' : 'months';
if($diff>=12){$diff/=12;$var1=floor($diff);$var=$var1<=1 ? 'year' : 'years';}}}}
echo $var1,' ',$var,' ago';
}
How can I delete Docker's images?
To delete some Docker image you must execute the following command:
$ docker rmi <docker_image_id>
So, to delete all Docker images you can execute the following command:
$ docker rmi $(docker images -q)
Now, if you want delete all Docker images (including images that are in use), you can add the flag -f, for example:
$ docker rmi -f $(docker images -q)
Is there a stopwatch in Java?
Try this.
public class StopWatch {
private long startTime = 0;
private long stopTime = 0;
public StopWatch()
{
startTime = System.currentTimeMillis();
}
public void start() {
startTime = System.currentTimeMillis();
}
public void stop() {
stopTime = System.currentTimeMillis();
System.out.println("StopWatch: " + getElapsedTime() + " milliseconds.");
System.out.println("StopWatch: " + getElapsedTimeSecs() + " seconds.");
}
/**
* @param process_name
*/
public void stop(String process_name) {
stopTime = System.currentTimeMillis();
System.out.println(process_name + " StopWatch: " + getElapsedTime() + " milliseconds.");
System.out.println(process_name + " StopWatch: " + getElapsedTimeSecs() + " seconds.");
}
//elaspsed time in milliseconds
public long getElapsedTime() {
return stopTime - startTime;
}
//elaspsed time in seconds
public double getElapsedTimeSecs() {
double elapsed;
elapsed = ((double)(stopTime - startTime)) / 1000;
return elapsed;
}
}
Usage:
StopWatch watch = new StopWatch();
// do something
watch.stop();
Console:
StopWatch: 143 milliseconds.
StopWatch: 0.143 seconds.
Get mouse wheel events in jQuery?
my combination looks like this. it fades out and fades in on each scroll down/up. otherwise you have to scroll up to the header, for fading the header in.
var header = $("#header");
$('#content-container').bind('mousewheel', function(e){
if(e.originalEvent.wheelDelta > 0) {
if (header.data('faded')) {
header.data('faded', 0).stop(true).fadeTo(800, 1);
}
}
else{
if (!header.data('faded')) header.data('faded', 1).stop(true).fadeTo(800, 0);
}
});
the above one is not optimized for touch/mobile, I think this one does it better for all mobile:
var iScrollPos = 0;
var header = $("#header");
$('#content-container').scroll(function () {
var iCurScrollPos = $(this).scrollTop();
if (iCurScrollPos > iScrollPos) {
if (!header.data('faded')) header.data('faded', 1).stop(true).fadeTo(800, 0);
} else {
//Scrolling Up
if (header.data('faded')) {
header.data('faded', 0).stop(true).fadeTo(800, 1);
}
}
iScrollPos = iCurScrollPos;
});
How to find substring inside a string (or how to grep a variable)?
expr is used instead of [ rather than inside it, and variables are only expanded inside double quotes, so try this:
if expr match "$LIST" "$SOURCE"; then
But I'm not really clear what SOURCE is supposed to represent.
It looks like your code will read in a pattern from standard input, and exit if it matches a database alias, otherwise it will echo "ok". Is that what you want?
SVN repository backup strategies
I have compiled the steps I followed for the purpose of taking a backup of the remote SVN
repository of my project.
install svk (http://svk.bestpractical.com/view/SVKWin32)
install svn (http://sourceforge.net/projects/win32svn/files/1.6.16/Setup-Subversion-1.6.16.msi/download)
svk mirror //local <remote repository URL>
svk sync //local
This takes time and says that it is fetching the logs from repository. It creates a set of files inside C:\Documents and Settings\nverma\.svk\local.
To update this local repository with the latest set of changes from the remote one, just run the previous command from time to time.
Now you can play with your local repository (/home/user/.svk/local in this example) as if it were a normal SVN repository!
The only problem with this approach is that the local repository is created with a revision increments by the actual revision in the remote repository. As someone wrote:
The svk miror command generates a commit in the just created repository. So all the commits created by the subsequent sync will have revision numbers incremented by one as compared to the remote public repository.
But, this was OK for me as I only wanted some backup of the remote repository time to time, nothing else.
Verification:
To verify, use the SVN client with the local repository like this:
svn checkout "file:///C:/Documents and Settings\nverma/.svk/local/" <local-dir-path-to-checkout-onto>
This command then goes to checkout the latest revision from the local repository. At the end it says Checked out revision N. This N was one more than the actual revision found in the remote repository (due to the problem mentioned above).
To verify that svk also brought all the history, the SVN checkout was run with various older revisions using -r with 2, 10, 50 etc. Then the files in <local-dir-path-to-checkout-onto> were confirmed to be from that revision.
At the end, zip the directory C:/Documents and Settings\nverma/.svk/local/ and store the zip somewhere. Keep doing this regularly.
How to hash a password
I use a hash and a salt for my password encryption (it's the same hash that Asp.Net Membership uses):
private string PasswordSalt
{
get
{
var rng = new RNGCryptoServiceProvider();
var buff = new byte[32];
rng.GetBytes(buff);
return Convert.ToBase64String(buff);
}
}
private string EncodePassword(string password, string salt)
{
byte[] bytes = Encoding.Unicode.GetBytes(password);
byte[] src = Encoding.Unicode.GetBytes(salt);
byte[] dst = new byte[src.Length + bytes.Length];
Buffer.BlockCopy(src, 0, dst, 0, src.Length);
Buffer.BlockCopy(bytes, 0, dst, src.Length, bytes.Length);
HashAlgorithm algorithm = HashAlgorithm.Create("SHA1");
byte[] inarray = algorithm.ComputeHash(dst);
return Convert.ToBase64String(inarray);
}
Create a Path from String in Java7
From the javadocs..http://docs.oracle.com/javase/tutorial/essential/io/pathOps.html
Path p1 = Paths.get("/tmp/foo");
is the same as
Path p4 = FileSystems.getDefault().getPath("/tmp/foo");
Path p3 = Paths.get(URI.create("file:///Users/joe/FileTest.java"));
Path p5 = Paths.get(System.getProperty("user.home"),"logs", "foo.log");
In Windows, creates file C:\joe\logs\foo.log (assuming user home as C:\joe)
In Unix, creates file /u/joe/logs/foo.log (assuming user home as /u/joe)
How do I add comments to package.json for npm install?
Inspired by this thread, here's what we are using:
{
"//dependencies": {
"crypto-exchange": "Unified exchange API"
},
"dependencies": {
"crypto-exchange": "^2.3.3"
},
"//devDependencies": {
"chai": "Assertions",
"mocha": "Unit testing framwork",
"sinon": "Spies, Stubs, Mocks",
"supertest": "Test requests"
},
"devDependencies": {
"chai": "^4.1.2",
"mocha": "^4.0.1",
"sinon": "^4.1.3",
"supertest": "^3.0.0"
}
}
Spring MVC Multipart Request with JSON
As documentation says:
Raised when the part of a "multipart/form-data" request identified by
its name cannot be found.
This may be because the request is not a multipart/form-data either
because the part is not present in the request, or because the web
application is not configured correctly for processing multipart
requests -- e.g. no MultipartResolver.
Linux shell sort file according to the second column?
If this is UNIX:
sort -k 2 file.txt
You can use multiple -k flags to sort on more than one column. For example, to sort by family name then first name as a tie breaker:
sort -k 2,2 -k 1,1 file.txt
Relevant options from "man sort":
-k, --key=POS1[,POS2]
start a key at POS1, end it at POS2 (origin 1)
POS is F[.C][OPTS], where F is the field number and C the character position in the field. OPTS is one or more single-letter ordering options, which override global ordering options for that key. If no key is given, use the entire line as the key.
-t, --field-separator=SEP
use SEP instead of non-blank to blank transition
What is the difference between a mutable and immutable string in C#?
Strings are mutable because .NET use string pool behind the scene. It means :
string name = "My Country";
string name2 = "My Country";
Both name and name2 are referring to same memory location from string pool.
Now suppose you want to change name2 to :
name2 = "My Loving Country";
It will look in to string pool for the string "My Loving Country", if found you will get the reference of it other wise new string "My Loving Country" will be created in string pool and name2 will get reference of it.
But it this whole process "My Country" was not changed because other variable like name is still using it.
And that is the reason why string are IMMUTABLE.
StringBuilder works in different manner and don't use string pool. When we create any instance of StringBuilder :
var address = new StringBuilder(500);
It allocate memory chunk of size 500 bytes for this instance and all operation just modify this memory location and this memory not shared with any other object. And that is the reason why StringBuilder is MUTABLE.
I hope it will help.
Git: How configure KDiff3 as merge tool and diff tool
Just to extend the @Joseph's answer:
After applying these commands your global .gitconfig file will have the following lines (to speed up the process you can just copy them in the file):
[merge]
tool = kdiff3
[mergetool "kdiff3"]
path = C:/Program Files/KDiff3/kdiff3.exe
trustExitCode = false
[diff]
guitool = kdiff3
[difftool "kdiff3"]
path = C:/Program Files/KDiff3/kdiff3.exe
trustExitCode = false
How to sort a list of strings numerically?
If you want to use strings of the numbers better take another list as shown in my code it will work fine.
list1=["1","10","3","22","23","4","2","200"]
k=[]
for item in list1:
k.append(int(item))
k.sort()
print(k)
# [1, 2, 3, 4, 10, 22, 23, 200]
Opening database file from within SQLite command-line shell
You can attach one and even more databases and work with it in the same way like using sqlite dbname.db
sqlite3
:
sqlite> attach "mydb.sqlite" as db1;
and u can see all attached databases with
.databases
where in normal way the main is used for the command-line db
.databases
seq name file
--- --------------- ----------------------------------------------------------
0 main
1 temp
2 ttt c:\home\user\gg.ite
Docker compose port mapping
If you want to access redis from the host (127.0.0.1), you have to use the ports command.
redis:
build:
context: .
dockerfile: Dockerfile-redis
ports:
- "6379:6379"
Why can't I reference System.ComponentModel.DataAnnotations?
I searched for help on this topic as I came across the same issue.
Although the following may not be the Answer to the question asked originally in 2012 it may be a solution for those who come across this thread.
A way to solve this is to check where your project is within the solution. It turns out for my instance (I was trying to install a NuGet package but it wouldn't and the listed error came up) that my project file was not included within the solution directory although showing in the solution explorer. I deleted the project from the directory out of scope and re-added the project but this time within the correct location.
IndentationError: unindent does not match any outer indentation level
I got this error even though I didn't have any tabs in my code, and the reason was there was a superfluous closing parenthesis somewhere in my code. I should have figured this out earlier because it was messing up spaces before and after some equal signs... If you find anything off even after running Reformat code in your IDE (or manually running autopep8), make sure all your parentheses match, starting backwards from the weird spaces before/after the first equals sign.
is there any IE8 only css hack?
If needed small changes in CSS use \9 it targets IE8 and below (IE6, IE7, IE8)
.element {
color:green \9;
}
Best way is to use conditional comments in HTML, like this:
<!--[if IE 8]>
<style>...</style>
<![endif]-->
Request Monitoring in Chrome
I know this is an old thread but I thought I would chime in.
Chrome currently has a solution built in.
- Use
CTRL+SHIFT+I (or navigate to Current Page Control > Developer > Developer Tools. In the newer versions of Chrome, click the Wrench icon > Tools > Developer Tools.) to enable the Developer Tools.
- From within the developer tools click on the
Network button. If it isn't already, enable it for the session or always.
- Click the
"XHR" sub-button.
- Initiate an
AJAX call.
- You will see items begin to show up in the left column under
"Resources".
- Click the resource and there are 2 tabs showing the headers and return content.
ApiNotActivatedMapError for simple html page using google-places-api
Assuming you already have a application created under google developer console,
Follow the below steps
- Go to the following link
https://console.cloud.google.com/apis/dashboard? you will be getting the below page 
- Click on ENABLE APIS AND SERVICES you will be directed to following page
- Select the desired option - in this case "Maps JavaScript API"
- Click ENABLE button as below,
Note: Please use a server to load the html file
How to open a WPF Popup when another control is clicked, using XAML markup only?
I did something simple, but it works.
I used a typical ToggleButton, which I restyled as a textblock by changing its control template. Then I just bound the IsChecked property on the ToggleButton to the IsOpen property on the popup. Popup has some properties like StaysOpen that let you modify the closing behavior.
The following works in XamlPad.
<StackPanel>
<ToggleButton Name="button">
<ToggleButton.Template>
<ControlTemplate TargetType="ToggleButton">
<TextBlock>Click Me Here!!</TextBlock>
</ControlTemplate>
</ToggleButton.Template>
</ToggleButton>
<Popup IsOpen="{Binding IsChecked, ElementName=button}" StaysOpen="False">
<Border Background="LightYellow">
<TextBlock>I'm the popup</TextBlock>
</Border>
</Popup>
</StackPanel>
CSS: On hover show and hide different div's at the same time?
http://jsfiddle.net/MBLZx/
Here is the code
_x000D_
_x000D_
.showme{ _x000D_
display: none;_x000D_
}_x000D_
.showhim:hover .showme{_x000D_
display : block;_x000D_
}_x000D_
.showhim:hover .ok{_x000D_
display : none;_x000D_
}
_x000D_
<div class="showhim">_x000D_
HOVER ME_x000D_
<div class="showme">hai</div>_x000D_
<div class="ok">ok</div>_x000D_
</div>_x000D_
_x000D_
_x000D_
_x000D_
_x000D_
How to redirect to an external URL in Angular2?
If you've been using the OnDestry lifecycle hook, you might be interested in using something like this before calling window.location.href=...
this.router.ngOnDestroy();
window.location.href = 'http://www.cnn.com/';
that will trigger the OnDestry callback in your component that you might like.
Ohh, and also:
import { Router } from '@angular/router';
is where you find the router.
---EDIT---
Sadly, I might have been wrong in the example above. At least it's not working as exepected in my production code right now - so, until I have time to investigate further, I solve it like this (since my app really need the hook when possible)
this.router.navigate(["/"]).then(result=>{window.location.href = 'http://www.cnn.com/';});
Basically routing to any (dummy) route to force the hook, and then navigate as requested.
With MySQL, how can I generate a column containing the record index in a table?
I found the original answer incredibly helpful but I also wanted to grab a certain set of rows based on the row numbers I was inserting. As such, I wrapped the entire original answer in a subquery so that I could reference the row number I was inserting.
SELECT * FROM
(
SELECT *, @curRow := @curRow + 1 AS "row_number"
FROM db.tableName, (SELECT @curRow := 0) r
) as temp
WHERE temp.row_number BETWEEN 1 and 10;
Having a subquery in a subquery is not very efficient, so it would be worth testing whether you get a better result by having your SQL server handle this query, or fetching the entire table and having the application/web server manipulate the rows after the fact.
Personally my SQL server isn't overly busy, so having it handle the nested subqueries was preferable.
Making a DateTime field in a database automatic?
Just right click on that column and select properties and write getdate()in Default value or binding.like image:
If you want do it in CodeFirst in EF you should add this attributes befor of your column definition:
[Databasegenerated(Databaseoption.computed)]
this attributes can found in System.ComponentModel.Dataannotion.Schema.
In my opinion first one is better:))
Excel VBA - Sum up a column
I think you are misinterpreting the source of the error; rExternalTotal appears to be equal to a single cell.
rReportData.offset(0,0) is equal to rReportData
rReportData.offset(261,0).end(xlUp) is likely also equal to rReportData, as you offset by 261 rows and then use the .end(xlUp) function which selects the top of a contiguous data range.
If you are interested in the sum of just a column, you can just refer to the whole column:
dExternalTotal = Application.WorksheetFunction.Sum(columns("A:A"))
or
dExternalTotal = Application.WorksheetFunction.Sum(columns((rReportData.column))
The worksheet function sum will correctly ignore blank spaces.
Let me know if this helps!
How to use MapView in android using google map V2?
I created dummy sample for Google Maps v2 Android with Kotlin and AndroidX
You can find complete project here: github-link
MainActivity.kt
class MainActivity : AppCompatActivity() {
val position = LatLng(-33.920455, 18.466941)
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
with(mapView) {
// Initialise the MapView
onCreate(null)
// Set the map ready callback to receive the GoogleMap object
getMapAsync{
MapsInitializer.initialize(applicationContext)
setMapLocation(it)
}
}
}
private fun setMapLocation(map : GoogleMap) {
with(map) {
moveCamera(CameraUpdateFactory.newLatLngZoom(position, 13f))
addMarker(MarkerOptions().position(position))
mapType = GoogleMap.MAP_TYPE_NORMAL
setOnMapClickListener {
Toast.makeText(this@MainActivity, "Clicked on map", Toast.LENGTH_SHORT).show()
}
}
}
override fun onResume() {
super.onResume()
mapView.onResume()
}
override fun onPause() {
super.onPause()
mapView.onPause()
}
override fun onDestroy() {
super.onDestroy()
mapView.onDestroy()
}
override fun onLowMemory() {
super.onLowMemory()
mapView.onLowMemory()
}
}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" package="com.murgupluoglu.googlemap">
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme"
tools:ignore="GoogleAppIndexingWarning">
<meta-data
android:name="com.google.android.geo.API_KEY"
android:value="API_KEY_HERE" />
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
</application>
</manifest>
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<com.google.android.gms.maps.MapView
android:layout_width="0dp"
android:layout_height="0dp"
android:id="@+id/mapView"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"/>
</androidx.constraintlayout.widget.ConstraintLayout>
SQL Query with Join, Count and Where
I have used sub-query and it worked great!
SELECT *,(SELECT count(*) FROM $this->tbl_news WHERE
$this->tbl_news.cat_id=$this->tbl_categories.cat_id) as total_news FROM
$this->tbl_categories
how to change onclick event with jquery?
@Amirali
console.log(document.getElementById("SAVE_FOOTER"));
document.getElementById("SAVE_FOOTER").attribute("onclick","console.log('c')");
throws:
Uncaught TypeError: document.getElementById(...).attribute is not a function
in chrome.
Element exists and is dumped in console;
Can I use a binary literal in C or C++?
Based on some other answers, but this one will reject programs with illegal binary literals. Leading zeroes are optional.
template<bool> struct BinaryLiteralDigit;
template<> struct BinaryLiteralDigit<true> {
static bool const value = true;
};
template<unsigned long long int OCT, unsigned long long int HEX>
struct BinaryLiteral {
enum {
value = (BinaryLiteralDigit<(OCT%8 < 2)>::value && BinaryLiteralDigit<(HEX >= 0)>::value
? (OCT%8) + (BinaryLiteral<OCT/8, 0>::value << 1)
: -1)
};
};
template<>
struct BinaryLiteral<0, 0> {
enum {
value = 0
};
};
#define BINARY_LITERAL(n) BinaryLiteral<0##n##LU, 0x##n##LU>::value
Example:
#define B BINARY_LITERAL
#define COMPILE_ERRORS 0
int main (int argc, char ** argv) {
int _0s[] = { 0, B(0), B(00), B(000) };
int _1s[] = { 1, B(1), B(01), B(001) };
int _2s[] = { 2, B(10), B(010), B(0010) };
int _3s[] = { 3, B(11), B(011), B(0011) };
int _4s[] = { 4, B(100), B(0100), B(00100) };
int neg8s[] = { -8, -B(1000) };
#if COMPILE_ERRORS
int errors[] = { B(-1), B(2), B(9), B(1234567) };
#endif
return 0;
}
How to handle command-line arguments in PowerShell
You are reinventing the wheel. Normal PowerShell scripts have parameters starting with -, like script.ps1 -server http://devserver
Then you handle them in param section in the beginning of the file.
You can also assign default values to your params, read them from console if not available or stop script execution:
param (
[string]$server = "http://defaultserver",
[Parameter(Mandatory=$true)][string]$username,
[string]$password = $( Read-Host "Input password, please" )
)
Inside the script you can simply
write-output $server
since all parameters become variables available in script scope.
In this example, the $server gets a default value if the script is called without it, script stops if you omit the -username parameter and asks for terminal input if -password is omitted.
Update:
You might also want to pass a "flag" (a boolean true/false parameter) to a PowerShell script. For instance, your script may accept a "force" where the script runs in a more careful mode when force is not used.
The keyword for that is [switch] parameter type:
param (
[string]$server = "http://defaultserver",
[string]$password = $( Read-Host "Input password, please" ),
[switch]$force = $false
)
Inside the script then you would work with it like this:
if ($force) {
//deletes a file or does something "bad"
}
Now, when calling the script you'd set the switch/flag parameter like this:
.\yourscript.ps1 -server "http://otherserver" -force
If you explicitly want to state that the flag is not set, there is a special syntax for that
.\yourscript.ps1 -server "http://otherserver" -force:$false
Links to relevant Microsoft documentation (for PowerShell 5.0; tho versions 3.0 and 4.0 are also available at the links):
Dump a list in a pickle file and retrieve it back later
Pickling will serialize your list (convert it, and it's entries to a unique byte string), so you can save it to disk. You can also use pickle to retrieve your original list, loading from the saved file.
So, first build a list, then use pickle.dump to send it to a file...
Python 3.4.1 (default, May 21 2014, 12:39:51)
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.2.79)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> mylist = ['I wish to complain about this parrot what I purchased not half an hour ago from this very boutique.', "Oh yes, the, uh, the Norwegian Blue...What's,uh...What's wrong with it?", "I'll tell you what's wrong with it, my lad. 'E's dead, that's what's wrong with it!", "No, no, 'e's uh,...he's resting."]
>>>
>>> import pickle
>>>
>>> with open('parrot.pkl', 'wb') as f:
... pickle.dump(mylist, f)
...
>>>
Then quit and come back later… and open with pickle.load...
Python 3.4.1 (default, May 21 2014, 12:39:51)
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.2.79)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import pickle
>>> with open('parrot.pkl', 'rb') as f:
... mynewlist = pickle.load(f)
...
>>> mynewlist
['I wish to complain about this parrot what I purchased not half an hour ago from this very boutique.', "Oh yes, the, uh, the Norwegian Blue...What's,uh...What's wrong with it?", "I'll tell you what's wrong with it, my lad. 'E's dead, that's what's wrong with it!", "No, no, 'e's uh,...he's resting."]
>>>
Importing a GitHub project into Eclipse
It can be done in two ways:
1.Use clone Git
2.You can set it up manually by rearranging folders given in it.
make a two separate folder 'src' and 'res' and place appropriate classes and xml file given by library. and then import project from eclipse and make it as library, that's it.
Android SDK manager won't open
I saw answers that provide workaround solutions by hard coding java.exe location and x86 / x86_64 architecture string in sdk\tools\android.bat. Those are quick solutions but did not solve the fundamental issue that I am actually curious of.
The actual problem that I encountered is, the batch script is not able to find another script/jar file and thus is failed to proceed. I could say the script was poorly written.
After I made the following changes in sdk\tools\android.bat, everything works like a charm.
Specifically, I added %~dp0\:
set java_exe=
call %~dp0\lib\find_java.bat
if not defined java_exe goto :EOF
...
for /f "delims=" %%a in ('"%java_exe%" -jar %~dp0\lib\archquery.jar') do set swt_path=lib\%%a
Now, try to launch the script and SDK Manager should come out.
p.s. My installation of OS, Java 8 and Android SDK are fresh and I did not do any of the extra configuration.
p.s. You may still need to configure PATH environment variable so that the script could find the suitable java.exe.
Post request with Wget?
Wget currently only supports x-www-form-urlencoded data. --post-file is not for transmitting files as form attachments, it expects data with the form: key=value&otherkey=example.
--post-data and --post-file work the same way: the only difference is that --post-data allows you to specify the data in the command line, while --post-file allows you to specify the path of the file that contain the data to send.
Here's the documentation:
--post-data=string
--post-file=file
Use POST as the method for all HTTP requests and send the specified data
in the request body. --post-data sends string as data, whereas
--post-file sends the contents of file. Other than that, they work in
exactly the same way. In particular, they both expect content of the
form "key1=value1&key2=value2", with percent-encoding for special
characters; the only difference is that one expects its content as a
command-line parameter and the other accepts its content from a file. In
particular, --post-file is not for transmitting files as form
attachments: those must appear as "key=value" data (with appropriate
percent-coding) just like everything else. Wget does not currently
support "multipart/form-data" for transmitting POST data; only
"application/x-www-form-urlencoded". Only one of --post-data and
--post-file should be specified.
Regarding your authentication token, it should either be provided in the header, in the path of the url, or in the data itself. This must be indicated somewhere in the documentation of the service you use. In a POST request, as in a GET request, you must specify the data using keys and values. This way the server will be able to receive multiple information with specific names. It's similar with variables.
Hence, you can't just send a magic token to the server, you also need to specify the name of the key. If the key is "token", then it should be token=YOUR_TOKEN.
wget --post-data 'user=foo&password=bar' http://example.com/auth.php
Also, you should consider using curl if you can because it is easier to send files using it. There are many examples on the Internet for that.
Rotate camera in Three.js with mouse
OrbitControls and TrackballControls seems to be good for this purpose.
controls = new THREE.TrackballControls( camera );
controls.rotateSpeed = 1.0;
controls.zoomSpeed = 1.2;
controls.panSpeed = 0.8;
controls.noZoom = false;
controls.noPan = false;
controls.staticMoving = true;
controls.dynamicDampingFactor = 0.3;
update in render
controls.update();
How to restore/reset npm configuration to default values?
To reset user defaults
Run this in the command line (or git bash on windows):
echo "" > $(npm config get userconfig)
npm config edit
To reset global defaults
echo "" > $(npm config get globalconfig)
npm config --global edit
If you need sudo then run this instead:
sudo sh -c 'echo "" > $(npm config get globalconfig)'
How do I perform query filtering in django templates
The other option is that if you have a filter that you always want applied, to add a custom manager on the model in question which always applies the filter to the results returned.
A good example of this is a Event model, where for 90% of the queries you do on the model you are going to want something like Event.objects.filter(date__gte=now), i.e. you're normally interested in Events that are upcoming. This would look like:
class EventManager(models.Manager):
def get_query_set(self):
now = datetime.now()
return super(EventManager,self).get_query_set().filter(date__gte=now)
And in the model:
class Event(models.Model):
...
objects = EventManager()
But again, this applies the same filter against all default queries done on the Event model and so isn't as flexible some of the techniques described above.
How to export private key from a keystore of self-signed certificate
It is a little tricky. First you can use keytool to put the private key into PKCS12 format, which is more portable/compatible than Java's various keystore formats. Here is an example taking a private key with alias 'mykey' in a Java keystore and copying it into a PKCS12 file named myp12file.p12.
[note that on most screens this command extends beyond the right side of the box: you need to scroll right to see it all]
keytool -v -importkeystore -srckeystore .keystore -srcalias mykey -destkeystore myp12file.p12 -deststoretype PKCS12
Enter destination keystore password:
Re-enter new password:
Enter source keystore password:
[Storing myp12file.p12]
Now the file myp12file.p12 contains the private key in PKCS12 format which may be used directly by many software packages or further processed using the openssl pkcs12 command. For example,
openssl pkcs12 -in myp12file.p12 -nocerts -nodes
Enter Import Password:
MAC verified OK
Bag Attributes
friendlyName: mykey
localKeyID: 54 69 6D 65 20 31 32 37 31 32 37 38 35 37 36 32 35 37
Key Attributes: <No Attributes>
-----BEGIN RSA PRIVATE KEY-----
MIIC...
.
.
.
-----END RSA PRIVATE KEY-----
Prints out the private key unencrypted.
Note that this is a private key, and you are responsible for appreciating the security implications of removing it from your Java keystore and moving it around.
Measuring execution time of a function in C++
You can have a simple class which can be used for this kind of measurements.
class duration_printer {
public:
duration_printer() : __start(std::chrono::high_resolution_clock::now()) {}
~duration_printer() {
using namespace std::chrono;
high_resolution_clock::time_point end = high_resolution_clock::now();
duration<double> dur = duration_cast<duration<double>>(end - __start);
std::cout << dur.count() << " seconds" << std::endl;
}
private:
std::chrono::high_resolution_clock::time_point __start;
};
The only thing is needed to do is to create an object in your function at the beginning of that function
void veryLongExecutingFunction() {
duration_calculator dc;
for(int i = 0; i < 100000; ++i) std::cout << "Hello world" << std::endl;
}
int main() {
veryLongExecutingFunction();
return 0;
}
and that's it. The class can be modified to fit your requirements.
Media Queries: How to target desktop, tablet, and mobile?
- Extra small devices (phones, up to 480px)
- Small devices (tablets, 768px and up)
- Medium devices (big landscape tablets, laptops, and
desktops, 992px and up)
- Large devices (large desktops, 1200px and up)
- portrait e-readers (Nook/Kindle), smaller tablets - min-width:481px
- portrait tablets, portrait iPad, landscape e-readers - min-width:641px
- tablet, landscape iPad, lo-res laptops - min-width:961px
- HTC One device-width: 360px device-height: 640px -webkit-device-pixel-ratio: 3
- Samsung Galaxy S2 device-width: 320px device-height: 534px -webkit-device-pixel-ratio: 1.5 (min--moz-device-pixel-ratio: 1.5), (-o-min-device-pixel-ratio:
3/2), (min-device-pixel-ratio: 1.5
- Samsung Galaxy S3 device-width: 320px device-height: 640px -webkit-device-pixel-ratio: 2 (min--moz-device-pixel-ratio: 2), - Older Firefox browsers (prior to Firefox 16) -
- Samsung Galaxy S4 device-width: 320px device-height: 640px -webkit-device-pixel-ratio: 3
- LG Nexus 4 device-width: 384px device-height: 592px -webkit-device-pixel-ratio: 2
- Asus Nexus 7 device-width: 601px device-height: 906px
-webkit-min-device-pixel-ratio: 1.331) and (-webkit-max-device-pixel-ratio: 1.332)
- iPad 1 and 2, iPad Mini device-width: 768px device-height: 1024px -webkit-device-pixel-ratio: 1
- iPad 3 and 4 device-width: 768px device-height: 1024px -webkit-device-pixel-ratio: 2)
- iPhone 3G device-width: 320px device-height: 480px -webkit-device-pixel-ratio: 1)
- iPhone 4 device-width: 320px device-height: 480px -webkit-device-pixel-ratio: 2)
- iPhone 5 device-width: 320px device-height: 568px -webkit-device-pixel-ratio: 2)
Anaconda Navigator won't launch (windows 10)
I struggled with this problem for a couple of hours (got the same error message you showed in your attachment). I knew the problem had to do with the path variable, specifically the PYTHONHOME variable.
I finally found I had set the PYTHONHOME path to the python.exe file (C:\Anaconda3\python.exe). It should be set to the Anaconda folder that contains the python.exe file (C:\Anaconda3).
After that I could run the Anaconda Navigator.
Dynamic Web Module 3.0 -- 3.1
- Go to Workspace location
- select your project folder
- .setting folder
- edit "org.eclipse.wst.common.project.facet.core"
- change installed facet="jst.web" version="3.0"
MATLAB - multiple return values from a function?
Use the following in the function you will call and it will work just fine.
[a b c] = yourfunction(optional)
%your code
a = 5;
b = 7;
c = 10;
return
end
This is a way to call the function both from another function and from the command terminal
[aa bb cc] = yourfunction(optional);
The variables aa, bb and cc now hold the return variables.
ORA-01036: illegal variable name/number when running query through C#
I was having the same problem in an application that I was maintaining, among all the adjustments to prepare the environment, I also spent almost an hour banging my head with this error "ORA-01036: illegal variable name / number" until I found out that the application connection was pointed to an outdated database, so the application passed two more parameters to the outdated database procedure causing the error.
.c vs .cc vs. .cpp vs .hpp vs .h vs .cxx
Those extensions aren't really new, they are old. :-)
When C++ was new, some people wanted to have a .c++ extension for the source files, but that didn't work on most file systems. So they tried something close to that, like .cxx, or .cpp instead.
Others thought about the language name, and "incrementing" .c to get .cc or even .C in some cases. Didn't catch on that much.
Some believed that if the source is .cpp, the headers ought to be .hpp to match. Moderately successful.
Android Endless List
One solution is to implement an OnScrollListener and make changes (like adding items, etc.) to the ListAdapter at a convenient state in its onScroll method.
The following ListActivity shows a list of integers, starting with 40, adding items when the user scrolls to the end of the list.
public class Test extends ListActivity implements OnScrollListener {
Aleph0 adapter = new Aleph0();
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setListAdapter(adapter);
getListView().setOnScrollListener(this);
}
public void onScroll(AbsListView view,
int firstVisible, int visibleCount, int totalCount) {
boolean loadMore = /* maybe add a padding */
firstVisible + visibleCount >= totalCount;
if(loadMore) {
adapter.count += visibleCount; // or any other amount
adapter.notifyDataSetChanged();
}
}
public void onScrollStateChanged(AbsListView v, int s) { }
class Aleph0 extends BaseAdapter {
int count = 40; /* starting amount */
public int getCount() { return count; }
public Object getItem(int pos) { return pos; }
public long getItemId(int pos) { return pos; }
public View getView(int pos, View v, ViewGroup p) {
TextView view = new TextView(Test.this);
view.setText("entry " + pos);
return view;
}
}
}
You should obviously use separate threads for long running actions (like loading web-data) and might want to indicate progress in the last list item (like the market or gmail apps do).
Search input with an icon Bootstrap 4
Update 2019
Why not use an input-group?
<div class="input-group col-md-4">
<input class="form-control py-2" type="search" value="search" id="example-search-input">
<span class="input-group-append">
<button class="btn btn-outline-secondary" type="button">
<i class="fa fa-search"></i>
</button>
</span>
</div>
And, you can make it appear inside the input using the border utils...
<div class="input-group col-md-4">
<input class="form-control py-2 border-right-0 border" type="search" value="search" id="example-search-input">
<span class="input-group-append">
<button class="btn btn-outline-secondary border-left-0 border" type="button">
<i class="fa fa-search"></i>
</button>
</span>
</div>
Or, using a input-group-text w/o the gray background so the icon appears inside the input...
<div class="input-group">
<input class="form-control py-2 border-right-0 border" type="search" value="search" id="example-search-input">
<span class="input-group-append">
<div class="input-group-text bg-transparent"><i class="fa fa-search"></i></div>
</span>
</div>
Alternately, you can use the grid (row>col-) with no gutter spacing:
<div class="row no-gutters">
<div class="col">
<input class="form-control border-secondary border-right-0 rounded-0" type="search" value="search" id="example-search-input4">
</div>
<div class="col-auto">
<button class="btn btn-outline-secondary border-left-0 rounded-0 rounded-right" type="button">
<i class="fa fa-search"></i>
</button>
</div>
</div>
Or, prepend the icon like this...
<div class="input-group">
<span class="input-group-prepend">
<div class="input-group-text bg-transparent border-right-0">
<i class="fa fa-search"></i>
</div>
</span>
<input class="form-control py-2 border-left-0 border" type="search" value="..." id="example-search-input" />
<span class="input-group-append">
<button class="btn btn-outline-secondary border-left-0 border" type="button">
Search
</button>
</span>
</div>
Demo of all Bootstrap 4 icon input options
Example with validation icons
SSL: error:0B080074:x509 certificate routines:X509_check_private_key:key values mismatch
For Nginx:
openssl req -newkey rsa:2048 -nodes -keyout domain.com.key -out domain.com.csr
SSL file domain_com.crt and domain_com.ca-bundle files, then copy new file in paste domain.com.chained.crt.
3: Add nginx files:
ssl_certificate /home/user/domain_ssl/domain.com.chained.crt;ssl_certificate_key /home/user/domain_ssl/domain.com.key;
Lates restart Nginx.
Write string to output stream
You can create a PrintStream wrapping around your OutputStream and then just call it's print(String):
final OutputStream os = new FileOutputStream("/tmp/out");
final PrintStream printStream = new PrintStream(os);
printStream.print("String");
printStream.close();
HTML/CSS: Making two floating divs the same height
I had similar problem and in my opinion best option is to use just a little bit of javascript or jquery.
You can get wanted divs to be same height by getting highest div value and applying that value to all other divs. If you have many divs and many solutions i suggest to write little advance js code to find out which of all divs is the highest and then use it's value.
With jquery and 2 divs it's very simple, here is example code:
$('.smaller-div').css('height',$('.higher-div').css('height'));
And for the end, there is 1 last thing.
Their padding (top and bottom) must be the same ! If one have larger padding you need to eliminate padding difference.
The POM for project is missing, no dependency information available
Change:
<!-- ANT4X -->
<dependency>
<groupId>net.sourceforge</groupId>
<artifactId>ant4x</artifactId>
<version>${net.sourceforge.ant4x-version}</version>
<scope>provided</scope>
</dependency>
To:
<!-- ANT4X -->
<dependency>
<groupId>net.sourceforge.ant4x</groupId>
<artifactId>ant4x</artifactId>
<version>${net.sourceforge.ant4x-version}</version>
<scope>provided</scope>
</dependency>
The groupId of net.sourceforge was incorrect. The correct value is net.sourceforge.ant4x.
Java JTable getting the data of the selected row
Just simple like this:
tbl.addMouseListener(new MouseListener() {
@Override
public void mouseReleased(MouseEvent e) {
}
@Override
public void mousePressed(MouseEvent e) {
String selectedCellValue = (String) tbl.getValueAt(tbl.getSelectedRow() , tbl.getSelectedColumn());
System.out.println(selectedCellValue);
}
@Override
public void mouseExited(MouseEvent e) {
}
@Override
public void mouseEntered(MouseEvent e) {
}
@Override
public void mouseClicked(MouseEvent e) {
}
});
Spring RestTemplate timeout
This question is the first link for a Spring Boot search, therefore, would be great to put here the solution recommended in the official documentation. Spring Boot has its own convenience bean RestTemplateBuilder:
@Bean
public RestTemplate restTemplate(
RestTemplateBuilder restTemplateBuilder) {
return restTemplateBuilder
.setConnectTimeout(Duration.ofSeconds(500))
.setReadTimeout(Duration.ofSeconds(500))
.build();
}
Manual creation of RestTemplate instances is a potentially troublesome approach because other auto-configured beans are not being injected in manually created instances.
R Error in x$ed : $ operator is invalid for atomic vectors
From the help file about $ (See ?"$") you can read:
$ is only valid for recursive objects, and is only discussed in the section below on recursive objects.
Now, let's check whether x is recursive
> is.recursive(x)
[1] FALSE
A recursive object has a list-like structure. A vector is not recursive, it is an atomic object instead, let's check
> is.atomic(x)
[1] TRUE
Therefore you get an error when applying $ to a vector (non-recursive object), use [ instead:
> x["ed"]
ed
2
You can also use getElement
> getElement(x, "ed")
[1] 2
WPF Databinding: How do I access the "parent" data context?
This will also work:
<Hyperlink Command="{Binding RelativeSource={RelativeSource AncestorType=ItemsControl},
Path=DataContext.AllowItemCommand}" />
ListView will inherit its DataContext from Window, so it's available at this point, too.
And since ListView, just like similar controls (e. g. Gridview, ListBox, etc.), is a subclass of ItemsControl, the Binding for such controls will work perfectly.
How to get the jQuery $.ajax error response text?
This is what worked for me
function showErrorMessage(xhr, status, error) {
if (xhr.responseText != "") {
var jsonResponseText = $.parseJSON(xhr.responseText);
var jsonResponseStatus = '';
var message = '';
$.each(jsonResponseText, function(name, val) {
if (name == "ResponseStatus") {
jsonResponseStatus = $.parseJSON(JSON.stringify(val));
$.each(jsonResponseStatus, function(name2, val2) {
if (name2 == "Message") {
message = val2;
}
});
}
});
alert(message);
}
}
Get CPU Usage from Windows Command Prompt
The following works correctly on Windows 7 Ultimate from an elevated command prompt:
C:\Windows\system32>typeperf "\Processor(_Total)\% Processor Time"
"(PDH-CSV 4.0)","\\vm\Processor(_Total)\% Processor Time"
"02/01/2012 14:10:59.361","0.648721"
"02/01/2012 14:11:00.362","2.986384"
"02/01/2012 14:11:01.364","0.000000"
"02/01/2012 14:11:02.366","0.000000"
"02/01/2012 14:11:03.367","1.038332"
The command completed successfully.
C:\Windows\system32>
Or for a snapshot:
C:\Windows\system32>wmic cpu get loadpercentage
LoadPercentage
8
How do I create a Bash alias?
In my .bashrc file the following lines were there by default:
# Alias definitions.
# You may want to put all your additions into a separate file like
# ~/.bash_aliases, instead of adding them here directly.
# See /usr/share/doc/bash-doc/examples in the bash-doc package.
if [ -f ~/.bash_aliases ]; then
. ~/.bash_aliases
fi
Hence, in my platform .bash_aliases is the file used for aliases by default (and the one I use). I'm not an OS X user, but I guess that if you open your .bashrc file, you'll be able to identify what's the file commonly used for aliases in your platform.
SSRS - Checking whether the data is null
Or in your SQL query wrap that field with IsNull or Coalesce (SQL Server).
Either way works, I like to put that logic in the query so the report has to do less.
How to set full calendar to a specific start date when it's initialized for the 1st time?
This can be used in v5.3.2 to goto a date after initialization
calendar.gotoDate( '2020-09-12' );
eg on datepicker change
var calendarEl = document.getElementById('calendar');
var calendar = new FullCalendar.Calendar(calendarEl, {
...
initialDate: '2020-09-02',
...
});
$(".date-picker").change(function(){
var date = $(this).val();
calendar.gotoDate( date );
});
finding and replacing elements in a list
The following is a very straightforward method in Python 3.x
a = [1,2,3,4,5,1,2,3,4,5,1] #Replacing every 1 with 10
for i in range(len(a)):
if a[i] == 1:
a[i] = 10
print(a)
This method works. Comments are welcome. Hope it helps :)
Also try understanding how outis's and damzam's solutions work. List compressions and lambda function are useful tools.
Activity has leaked window that was originally added
The answers to this question were all correct, but a little confusing for me to actually understand why. After playing around for around 2 hours the reason to this error (in my case) hit me:
You already know, from reading other answers, that the has X has leaked window DecorView@d9e6131[] error means a dialog was open when your app closed. But why?
It could be, that your app crashed for some other reason while your dialog was open
This lead to your app closing because of some bug in your code, which lead to the dialog remaining open at the same time as your app closed due to the other error.
So, look through your logical. Solve the first error, and then the second error will solve itself
One error causes another, which causes another, like DOMINOS!
How to make MySQL table primary key auto increment with some prefix
Create a table with a normal numeric auto_increment ID, but either define it with ZEROFILL, or use LPAD to add zeroes when selecting. Then CONCAT the values to get your intended behavior. Example #1:
create table so (
id int(3) unsigned zerofill not null auto_increment primary key,
name varchar(30) not null
);
insert into so set name = 'John';
insert into so set name = 'Mark';
select concat('LHPL', id) as id, name from so;
+---------+------+
| id | name |
+---------+------+
| LHPL001 | John |
| LHPL002 | Mark |
+---------+------+
Example #2:
create table so (
id int unsigned not null auto_increment primary key,
name varchar(30) not null
);
insert into so set name = 'John';
insert into so set name = 'Mark';
select concat('LHPL', LPAD(id, 3, 0)) as id, name from so;
+---------+------+
| id | name |
+---------+------+
| LHPL001 | John |
| LHPL002 | Mark |
+---------+------+
Code not running in IE 11, works fine in Chrome
Follow this method if problem comes when working with angular2+ projects
I was looking for a solution when i got this error, and it got me here. But this question seems to be specific but the error is not, its a generic error. This is a common error for angular developers dealing with Internet Explorer.
I had the same issue while working with angular 2+, and it got resolved just by few simple steps.
In Angular latest versions, there are come commented codes in the polyfills.ts shows all the polyfills required for the smooth running in Internet Explorer versions IE09,IE10 and IE11
/** IE9, IE10 and IE11 requires all of the following polyfills. **/
//import 'core-js/es6/symbol';
//import 'core-js/es6/object';
//import 'core-js/es6/function';
//import 'core-js/es6/parse-int';
//import 'core-js/es6/parse-float';
//import 'core-js/es6/number';
//import 'core-js/es6/math';
//import 'core-js/es6/string';
//import 'core-js/es6/date';
//import 'core-js/es6/array';
//import 'core-js/es6/regexp';
//import 'core-js/es6/map';
//import 'core-js/es6/weak-map';
//import 'core-js/es6/set';
Uncomment the codes and it would work perfectly in IE browsers
/** IE9, IE10 and IE11 requires all of the following polyfills. **/
import 'core-js/es6/symbol';
import 'core-js/es6/object';
import 'core-js/es6/function';
import 'core-js/es6/parse-int';
import 'core-js/es6/parse-float';
import 'core-js/es6/number';
import 'core-js/es6/math';
import 'core-js/es6/string';
import 'core-js/es6/date';
import 'core-js/es6/array';
import 'core-js/es6/regexp';
import 'core-js/es6/map';
import 'core-js/es6/weak-map';
import 'core-js/es6/set';
But you might see a performance drop in IE browsers compared to others :(
How to create an Oracle sequence starting with max value from a table?
Here I have my example which works just fine:
declare
ex number;
begin
select MAX(MAX_FK_ID) + 1 into ex from TABLE;
If ex > 0 then
begin
execute immediate 'DROP SEQUENCE SQ_NAME';
exception when others then
null;
end;
execute immediate 'CREATE SEQUENCE SQ_NAME INCREMENT BY 1 START WITH ' || ex || ' NOCYCLE CACHE 20 NOORDER';
end if;
end;
How to increment a datetime by one day?
You can also import timedelta so the code is cleaner.
from datetime import datetime, timedelta
date = datetime.now() + timedelta(seconds=[delta_value])
Then convert to date to string
date = date.strftime('%Y-%m-%d %H:%M:%S')
Python one liner is
date = (datetime.now() + timedelta(seconds=[delta_value])).strftime('%Y-%m-%d %H:%M:%S')
Trim spaces from start and end of string
Here, this should do all that you need
function doSomething(input) {
return input
.replace(/^\s\s*/, '') // Remove Preceding white space
.replace(/\s\s*$/, '') // Remove Trailing white space
.replace(/([\s]+)/g, '-'); // Replace remaining white space with dashes
}
alert(doSomething(" something with some whitespace "));
Global variable Python classes
What you have is correct, though you will not call it global, it is a class attribute and can be accessed via class e.g Shape.lolwut or via an instance e.g. shape.lolwut but be careful while setting it as it will set an instance level attribute not class attribute
class Shape(object):
lolwut = 1
shape = Shape()
print Shape.lolwut, # 1
print shape.lolwut, # 1
# setting shape.lolwut would not change class attribute lolwut
# but will create it in the instance
shape.lolwut = 2
print Shape.lolwut, # 1
print shape.lolwut, # 2
# to change class attribute access it via class
Shape.lolwut = 3
print Shape.lolwut, # 3
print shape.lolwut # 2
output:
1 1 1 2 3 2
Somebody may expect output to be 1 1 2 2 3 3 but it would be incorrect
Adding JPanel to JFrame
Instead of having your Test2 class contain a JPanel, you should have it subclass JPanel:
public class Test2 extends JPanel {
Test2(){
...
}
More details:
JPanel is a subclass of Component, so any method that takes a Component as an argument can also take a JPanel as an argument.
Older versions didn't let you add directly to a JFrame; you had to use JFrame.getContentPane().add(Component). If you're using an older version, this might also be an issue. Newer versions of Java do let you call JFrame.add(Component) directly.
Unable to read data from the transport connection : An existing connection was forcibly closed by the remote host
I received this error when calling a web-service. The issue was also related to transport level security. I could call the web-service through a website project, but when reusing the same code in a test project I would get a WebException that contained this message. Adding the following line before making the call resolved the issue:
System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;
Edit
System.Net.ServicePointManager.SecurityProtocol - This property
selects the version of the Secure Sockets Layer (SSL) or Transport
Layer Security (TLS) protocol to use for new connections that use the
Secure Hypertext Transfer Protocol (HTTPS) scheme only; existing
connections are not changed.
I believe the SecurityProtocol configuration is important during the TLS handshake when selecting the protocol version.
TLS handshake - This protocol is used to exchange all the information required by both sides for the exchange of the actual application data by TLS.
ClientHello - A client sends a ClientHello message specifying the highest TLS protocol version it supports ...
ServerHello - The server responds with a ServerHello message, containing the chosen protocol version ... The chosen protocol version should be the highest that both the client and server support. For example, if the client supports TLS version 1.1 and the server supports version 1.2, version 1.1 should be selected; version 1.2 should not be selected.
How do I reference a local image in React?
Inside public folder create an assets folder and place image path accordingly.
<img className="img-fluid"
src={`${process.env.PUBLIC_URL}/assets/images/uc-white.png`}
alt="logo"/>
How to display activity indicator in middle of the iphone screen?
import UIKit
class ViewController: UIViewController {
@IBOutlet weak var textLbl: UILabel!
var containerView = UIView()
var loadingView = UIView()
var activityIndicator = UIActivityIndicatorView()
override func viewDidLoad() {
super.viewDidLoad()
let _ = Timer.scheduledTimer(withTimeInterval: 10, repeats: false) { (_) in
self.textLbl.text = "Stop ActivitiIndicator"
self.activityIndicator.stopAnimating()
self.containerView.removeFromSuperview()
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
@IBAction func palyClicked(sender: AnyObject){
containerView.frame = self.view.frame
containerView.backgroundColor = UIColor(red: 0/255, green: 0/255, blue: 0/255, alpha: 0.3)
self.view.addSubview(containerView)
loadingView.frame = CGRect(x: 0, y: 0, width: 80, height: 80)
loadingView.center = self.view.center
loadingView.backgroundColor = UIColor(red: 0/255, green: 0/255, blue: 0/255, alpha: 0.5)
loadingView.clipsToBounds = true
loadingView.layer.cornerRadius = 10
containerView.addSubview(loadingView)
activityIndicator.frame = CGRect(x: 0, y: 0, width: 40, height: 40)
activityIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.whiteLarge
activityIndicator.center = CGPoint(x:loadingView.frame.size.width / 2, y:loadingView.frame.size.height / 2);
activityIndicator.startAnimating()
loadingView.addSubview(activityIndicator)
}
}
ArrayList of String Arrays
You can't force the String arrays to have a specific size.
You can do this:
private List<String[]> addresses = new ArrayList<String[]>();
but an array of any size can be added to this list.
However, as others have mentioned, the correct thing to do here is to create a separate class representing addresses. Then you would have something like:
private List<Address> addresses = new ArrayList<Address>();
Time complexity of Euclid's Algorithm
There's a great look at this on the wikipedia article.
It even has a nice plot of complexity for value pairs.
It is not O(a%b).
It is known (see article) that it will never take more steps than five times the number of digits in the smaller number. So the max number of steps grows as the number of digits (ln b). The cost of each step also grows as the number of digits, so the complexity is bound by O(ln^2 b) where b is the smaller number. That's an upper limit, and the actual time is usually less.
How to change dataframe column names in pyspark?
There are many ways to do that:
Option 1. Using selectExpr.
data = sqlContext.createDataFrame([("Alberto", 2), ("Dakota", 2)],
["Name", "askdaosdka"])
data.show()
data.printSchema()
# Output
#+-------+----------+
#| Name|askdaosdka|
#+-------+----------+
#|Alberto| 2|
#| Dakota| 2|
#+-------+----------+
#root
# |-- Name: string (nullable = true)
# |-- askdaosdka: long (nullable = true)
df = data.selectExpr("Name as name", "askdaosdka as age")
df.show()
df.printSchema()
# Output
#+-------+---+
#| name|age|
#+-------+---+
#|Alberto| 2|
#| Dakota| 2|
#+-------+---+
#root
# |-- name: string (nullable = true)
# |-- age: long (nullable = true)
Option 2. Using withColumnRenamed, notice that this method allows you to "overwrite" the same column. For Python3, replace xrange with range.
from functools import reduce
oldColumns = data.schema.names
newColumns = ["name", "age"]
df = reduce(lambda data, idx: data.withColumnRenamed(oldColumns[idx], newColumns[idx]), xrange(len(oldColumns)), data)
df.printSchema()
df.show()
Option 3. using
alias, in Scala you can also use as.
from pyspark.sql.functions import col
data = data.select(col("Name").alias("name"), col("askdaosdka").alias("age"))
data.show()
# Output
#+-------+---+
#| name|age|
#+-------+---+
#|Alberto| 2|
#| Dakota| 2|
#+-------+---+
Option 4. Using sqlContext.sql, which lets you use SQL queries on DataFrames registered as tables.
sqlContext.registerDataFrameAsTable(data, "myTable")
df2 = sqlContext.sql("SELECT Name AS name, askdaosdka as age from myTable")
df2.show()
# Output
#+-------+---+
#| name|age|
#+-------+---+
#|Alberto| 2|
#| Dakota| 2|
#+-------+---+
Web.Config Debug/Release
The web.config transforms that are part of Visual Studio 2010 use XSLT in order to "transform" the current web.config file into its .Debug or .Release version.
In your .Debug/.Release files, you need to add the following parameter in your connection string fields:
xdt:Transform="SetAttributes" xdt:Locator="Match(name)"
This will cause each connection string line to find the matching name and update the attributes accordingly.
Note: You won't have to worry about updating your providerName parameter in the transform files, since they don't change.
Here's an example from one of my apps. Here's the web.config file section:
<connectionStrings>
<add name="EAF" connectionString="[Test Connection String]" />
</connectionString>
And here's the web.config.release section doing the proper transform:
<connectionStrings>
<add name="EAF" connectionString="[Prod Connection String]"
xdt:Transform="SetAttributes"
xdt:Locator="Match(name)" />
</connectionStrings>
One added note: Transforms only occur when you publish the site, not when you simply run it with F5 or CTRL+F5. If you need to run an update against a given config locally, you will have to manually change your Web.config file for this.
For more details you can see the MSDN documentation
https://msdn.microsoft.com/en-us/library/dd465326(VS.100).aspx
Is there a java setting for disabling certificate validation?
Use cli utility keytool from java software distribution for import (and trust!) needed certificates
Sample:
From cli change dir to jre\bin
Check keystore (file found in jre\bin directory)
keytool -list -keystore ..\lib\security\cacerts
Enter keystore password: changeit
Download and save all certificates chain from needed server.
Add certificates (before need to remove "read-only" attribute on file "..\lib\security\cacerts")
keytool -alias REPLACE_TO_ANY_UNIQ_NAME -import -keystore ..\lib\security\cacerts -file "r:\root.crt"
accidentally I found such a simple tip.
Other solutions require the use of InstallCert.Java and JDK
source: http://www.java-samples.com/showtutorial.php?tutorialid=210
Is there a CSS selector for elements containing certain text?
@voyager's answer about using data-* attribute (e.g. data-gender="female|male" is the most effective and standards compliant approach as of 2017:
[data-gender='male'] {background-color: #000; color: #ccc;}
Pretty much most goals can be attained as there are some albeit limited selectors oriented around text. The ::first-letter is a pseudo-element that can apply limited styling to the first letter of an element. There is also a ::first-line pseudo-element besides obviously selecting the first line of an element (such as a paragraph) also implies that it is obvious that CSS could be used to extend this existing capability to style specific aspects of a textNode.
Until such advocacy succeeds and is implemented the next best thing I could suggest when applicable is to explode/split words using a space deliminator, output each individual word inside of a span element and then if the word/styling goal is predictable use in combination with :nth selectors:
$p = explode(' ',$words);
foreach ($p as $key1 => $value1)
{
echo '<span>'.$value1.'</span>;
}
Else if not predictable to, again, use voyager's answer about using data-* attribute. An example using PHP:
$p = explode(' ',$words);
foreach ($p as $key1 => $value1)
{
echo '<span data-word="'.$value1.'">'.$value1.'</span>;
}
Is there a wikipedia API just for retrieve content summary?
There's a way to get the entire "intro section" without any html parsing! Similar to AnthonyS's answer with an additional explaintext param, you can get the intro section text in plain text.
Query
Getting Stack Overflow's intro in plain text:
Using page title:
https://en.wikipedia.org/w/api.php?format=json&action=query&prop=extracts&exintro&explaintext&redirects=1&titles=Stack%20Overflow
or use pageids
https://en.wikipedia.org/w/api.php?format=json&action=query&prop=extracts&exintro&explaintext&redirects=1&pageids=21721040
JSON Response
(warnings stripped)
{
"query": {
"pages": {
"21721040": {
"pageid": 21721040,
"ns": 0,
"title": "Stack Overflow",
"extract": "Stack Overflow is a privately held website, the flagship site of the Stack Exchange Network, created in 2008 by Jeff Atwood and Joel Spolsky, as a more open alternative to earlier Q&A sites such as Experts Exchange. The name for the website was chosen by voting in April 2008 by readers of Coding Horror, Atwood's popular programming blog.\nIt features questions and answers on a wide range of topics in computer programming. The website serves as a platform for users to ask and answer questions, and, through membership and active participation, to vote questions and answers up or down and edit questions and answers in a fashion similar to a wiki or Digg. Users of Stack Overflow can earn reputation points and \"badges\"; for example, a person is awarded 10 reputation points for receiving an \"up\" vote on an answer given to a question, and can receive badges for their valued contributions, which represents a kind of gamification of the traditional Q&A site or forum. All user-generated content is licensed under a Creative Commons Attribute-ShareAlike license. Questions are closed in order to allow low quality questions to improve. Jeff Atwood stated in 2010 that duplicate questions are not seen as a problem but rather they constitute an advantage if such additional questions drive extra traffic to the site by multiplying relevant keyword hits in search engines.\nAs of April 2014, Stack Overflow has over 2,700,000 registered users and more than 7,100,000 questions. Based on the type of tags assigned to questions, the top eight most discussed topics on the site are: Java, JavaScript, C#, PHP, Android, jQuery, Python and HTML."
}
}
}
}
Documentation: API: query/prop=extracts
Edit: Added &redirects=1 as recommended in comments.
Edit: Added pageids example
How do I run a Python program?
If you want to run the #'.py' file
just write in print() in your code to actually see it get printed.
Unlike python IDLE, you need to specify what you want to print using print() command.
For eg.
import os
os.getcwd()
a=[1,2,3,4,5]
name= 'Python'
# Use print() function
print(a)
print(name)
OUTPUT
[1, 2, 3, 4, 5]
Python
Center content vertically on Vuetify
Still surprised that no one proposed the shortest solution with align-center justify-center to center content vertically and horizontally. Check this CodeSandbox and code below:
<v-container fluid fill-height>
<v-layout align-center justify-center>
<v-flex>
<!-- Some HTML elements... -->
</v-flex>
</v-layout>
</v-container>
Spring JDBC Template for calling Stored Procedures
There are a number of ways to call stored procedures in Spring.
If you use CallableStatementCreator to declare parameters, you will be using Java's standard interface of CallableStatement, i.e register out parameters and set them separately. Using SqlParameter abstraction will make your code cleaner.
I recommend you looking at SimpleJdbcCall. It may be used like this:
SimpleJdbcCall jdbcCall = new SimpleJdbcCall(jdbcTemplate)
.withSchemaName(schema)
.withCatalogName(package)
.withProcedureName(procedure)();
...
jdbcCall.addDeclaredParameter(new SqlParameter(paramName, OracleTypes.NUMBER));
...
jdbcCall.execute(callParams);
For simple procedures you may use jdbcTemplate's update method:
jdbcTemplate.update("call SOME_PROC (?, ?)", param1, param2);
How to roundup a number to the closest ten?
the second argument in ROUNDUP, eg =ROUNDUP(12345.6789,3) refers to the negative of the base-10 column with that power of 10, that you want rounded up. eg 1000 = 10^3, so to round up to the next highest 1000, use ,-3)
=ROUNDUP(12345.6789,-4) = 20,000
=ROUNDUP(12345.6789,-3) = 13,000
=ROUNDUP(12345.6789,-2) = 12,400
=ROUNDUP(12345.6789,-1) = 12,350
=ROUNDUP(12345.6789,0) = 12,346
=ROUNDUP(12345.6789,1) = 12,345.7
=ROUNDUP(12345.6789,2) = 12,345.68
=ROUNDUP(12345.6789,3) = 12,345.679
So, to answer your question:
if your value is in A1, use
=ROUNDUP(A1,-1)
how to run the command mvn eclipse:eclipse
I don't think one needs it any more. The latest versions of Eclipse have Maven plugin enabled. So you will just need to import a Maven project into Eclipse and no more as an existing project. Eclipse will create the needed .project, .settings, .classpath files based on your pom.xml and environment settings (installed Java version, etc.) . The earlier versions of Eclipse needed to have run the command mvn eclipse:eclipse which produced the same result.
How to declare a Fixed length Array in TypeScript
The javascript array has a constructor that accepts the length of the array:
let arr = new Array<number>(3);
console.log(arr); // [undefined × 3]
However, this is just the initial size, there's no restriction on changing that:
arr.push(5);
console.log(arr); // [undefined × 3, 5]
Typescript has tuple types which let you define an array with a specific length and types:
let arr: [number, number, number];
arr = [1, 2, 3]; // ok
arr = [1, 2]; // Type '[number, number]' is not assignable to type '[number, number, number]'
arr = [1, 2, "3"]; // Type '[number, number, string]' is not assignable to type '[number, number, number]'
onChange and onSelect in DropDownList
I bet the onchange is getting fired after the onselect, essentially re-enabling the select.
I'd recommend you implement only the onchange, inspect which option has been selected, and enable or disabled based on that.
To get the value of the selected option use:
document.getElementById("mySelect").options[document.getElementById("mySelect").selectedIndex].value
Which will yield .. nothing since you haven't specified a value for each option .. :(
<select id="mySelect" onChange="enable();">
<option onSelect="disable();" value="no">No</option>
<option onSelect="enable();" value="yes">Yes</option>
</select>
Now it will yield "yes" or "no"
Setting UILabel text to bold
Use attributed string:
// Define attributes
let labelFont = UIFont(name: "HelveticaNeue-Bold", size: 18)
let attributes :Dictionary = [NSFontAttributeName : labelFont]
// Create attributed string
var attrString = NSAttributedString(string: "Foo", attributes:attributes)
label.attributedText = attrString
You need to define attributes.
Using attributed string you can mix colors, sizes, fonts etc within one text
What do 1.#INF00, -1.#IND00 and -1.#IND mean?
From IEEE floating-point exceptions in C++ :
This page will answer the following questions.
- My program just printed out 1.#IND or 1.#INF (on Windows) or nan or inf (on Linux). What happened?
- How can I tell if a number is really a number and not a NaN or an infinity?
- How can I find out more details at runtime about kinds of NaNs and infinities?
- Do you have any sample code to show how this works?
- Where can I learn more?
These questions have to do with floating point exceptions. If you get some strange non-numeric output where you're expecting a number, you've either exceeded the finite limits of floating point arithmetic or you've asked for some result that is undefined. To keep things simple, I'll stick to working with the double floating point type. Similar remarks hold for float types.
Debugging 1.#IND, 1.#INF, nan, and inf
If your operation would generate a larger positive number than could be stored in a double, the operation will return 1.#INF on Windows or inf on Linux. Similarly your code will return -1.#INF or -inf if the result would be a negative number too large to store in a double. Dividing a positive number by zero produces a positive infinity and dividing a negative number by zero produces a negative infinity. Example code at the end of this page will demonstrate some operations that produce infinities.
Some operations don't make mathematical sense, such as taking the square root of a negative number. (Yes, this operation makes sense in the context of complex numbers, but a double represents a real number and so there is no double to represent the result.) The same is true for logarithms of negative numbers. Both sqrt(-1.0) and log(-1.0) would return a NaN, the generic term for a "number" that is "not a number". Windows displays a NaN as -1.#IND ("IND" for "indeterminate") while Linux displays nan. Other operations that would return a NaN include 0/0, 0*8, and 8/8. See the sample code below for examples.
In short, if you get 1.#INF or inf, look for overflow or division by zero. If you get 1.#IND or nan, look for illegal operations. Maybe you simply have a bug. If it's more subtle and you have something that is difficult to compute, see Avoiding Overflow, Underflow, and Loss of Precision. That article gives tricks for computing results that have intermediate steps overflow if computed directly.
Setting WPF image source in code
I am a new to WPF, but not in .NET.
I have spent five hours trying to add a PNG file to a "WPF Custom Control Library Project" in .NET 3.5 (Visual Studio 2010) and setting it as a background of an image-inherited control.
Nothing relative with URIs worked. I can not imagine why there is no method to get a URI from a resource file, through IntelliSense, maybe as:
Properties.Resources.ResourceManager.GetURI("my_image");
I've tried a lot of URIs and played with ResourceManager, and Assembly's GetManifest methods, but all there were exceptions or NULL values.
Here I pot the code that worked for me:
// Convert the image in resources to a Stream
Stream ms = new MemoryStream()
Properties.Resources.MyImage.Save(ms, ImageFormat.Png);
// Create a BitmapImage with the stream.
BitmapImage bitmap = new BitmapImage();
bitmap.BeginInit();
bitmap.StreamSource = ms;
bitmap.EndInit();
// Set as source
Source = bitmap;
C pointer to array/array of pointers disambiguation
int *arr1[5]
In this declaration, arr1 is an array of 5 pointers to integers.
Reason: Square brackets have higher precedence over * (dereferncing operator).
And in this type, number of rows are fixed (5 here), but number of columns is variable.
int (*arr2)[5]
In this declaration, arr2 is a pointer to an integer array of 5 elements.
Reason: Here, () brackets have higher precedence than [].
And in this type, number of rows is variable, but the number of columns is fixed (5 here).
Share variables between files in Node.js?
With a different opinion, I think the global variables might be the best choice if you are going to publish your code to npm, cuz you cannot be sure that all packages are using the same release of your code. So if you use a file for exporting a singleton object, it will cause issues here.
You can choose global, require.main or any other objects which are shared across files.
Otherwise, install your package as an optional dependency package can avoid this problem.
Please tell me if there are some better solutions.
Disabling Chrome cache for website development
I had the same problem, I tried :
- Control Shift R,
- Disable cache in F12
- Control F5.
Then I discovered that using a .appcache manifest for a non https site is deprecated.
I removed my site.appcache file and its reference in the html tag and now I'm seeing the latest version of each page!
How do I format a number with commas in T-SQL?
For SQL Server 2012+ implementations, you will have the ability to use the FORMAT to apply string formatting to non-string data types.
In the original question, the user had requested the ability to use commas as thousands separators. In a closed as duplicate question, the user had asked how they could apply currency formatting. The following query shows how to perform both tasks. It also demonstrates the application of culture to make this a more generic solution (addressing Tsiridis Dimitris's function to apply Greek special formatting)
-- FORMAT
-- http://msdn.microsoft.com/en-us/library/hh213505(v=sql.110).aspx
-- FORMAT does not do conversion, that's the domain of cast/convert/parse etc
-- Only accepts numeric and date/time data types for formatting.
--
-- Formatting Types
-- http://msdn.microsoft.com/en-us/library/26etazsy.aspx
-- Standard numeric format strings
-- http://msdn.microsoft.com/en-us/library/dwhawy9k.aspx
SELECT
-- c => currency
-- n => numeric
FORMAT(987654321, N'N', C.culture) AS some_number
, FORMAT(987654321, N'c', C.culture) AS some_currency
, C.culture
FROM
(
-- Language culture names
-- http://msdn.microsoft.com/en-us/library/ee825488(v=cs.20).aspx
VALUES
('en-US')
, ('en-GB')
, ('ja-JP')
, ('Ro-RO')
, ('el-GR')
) C (culture);
SQLFiddle for the above
Writing handler for UIAlertAction
create alert, tested in xcode 9
let alert = UIAlertController(title: "title", message: "message", preferredStyle: UIAlertControllerStyle.alert)
alert.addAction(UIAlertAction(title: "Ok", style: UIAlertActionStyle.default, handler: self.finishAlert))
self.present(alert, animated: true, completion: nil)
and the function
func finishAlert(alert: UIAlertAction!)
{
}
How do I implement onchange of <input type="text"> with jQuery?
If you want to trigger the event as you type, use the following:
$('input[name=myInput]').on('keyup', function() { ... });
If you want to trigger the event on leaving the input field, use the following:
$('input[name=myInput]').on('change', function() { ... });
404 Not Found The requested URL was not found on this server
In Ubuntu I did not found httpd.conf, It may not exit longer now.
Edit in apache2.conf file working for me.
cd /etc/apache2
sudo gedit apache2.conf
Here in apache2.conf change
<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride None
Require all granted
</Directory>
to
<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride All
Require all granted
</Directory>
can't start MySql in Mac OS 10.6 Snow Leopard
In order just to get MySQL working again (I haven't yet looked at startup), there is no need to reinstall . I've got my copy working by doing the following:
What you need to do is this:
sudo ln -s /usr/local/mysql-5.0.51a-osx10.5-x86_64 /usr/local/mysql
This creates a symbolic link from the /usr/local/mysql directory to the location where MySQL is. This is critical, because unless you carefully backed up all your databases with mysqldump before running the Leopard upgrade, that's where all your data lives - and restoring it simply from a whole-hard-drive backup is going to be hard.
Now you can go to the right directory and start up mysql:
cd /usr/local/mysql-5.0.51a-osx10.5-x86_64
sudo ./bin/mysqld_safe
You can now do the usual CTRL-Z to get back to the shell. To make sure mysqld is running, type:
sudo ps -A|grep mysql
I got something like this:
1220 ttys000 0:00.02 /bin/sh ./bin/mysqld_safe
1240 ttys000 0:00.39 /usr/local/mysql-5.0.51a-osx10.5-x86_64/bin/mysqld --basedir=/usr/local/mysql-5.0.51a-osx10.5-x86_64 --datadir=/usr/local/mysql-5.0.51a-osx10.5-x86_64/data --user=mysql --pid-file=/usr/local/mysql-5.0.51a-osx10.5-x86_64/data/dkmac-2.home.pid --port=3306 --socket=/tmp/mysql.soc
My copy of mysql now seems to work fine. At the very least, it's good enough to run mysqldump on all my databases, so that if I need to upgrade mysql by other means and dump my data directory, I'm still in good shape.
List directory tree structure in python?
A solution without your indentation:
for path, dirs, files in os.walk(given_path):
print path
for f in files:
print f
os.walk already does the top-down, depth-first walk you are looking for.
Ignoring the dirs list prevents the overlapping you mention.
'Class' does not contain a definition for 'Method'
I had the same problem. Turns out the project I was referencing did not get build.
When I went to the build configuration manager in visual studio and enabled the reference project , the issue got resolved.
OR condition in Regex
Try
\d \w |\d
or add a positive lookahead if you don't want to include the trailing space in the match
\d \w(?= )|\d
When you have two alternatives where one is an extension of the other, put the longer one first, otherwise it will have no opportunity to be matched.
JavaScript error: "is not a function"
Your LMSInitialize function is declared inside Scorm_API_12 function. So it can be seen only in Scorm_API_12 function's scope.
If you want to use this function like API.LMSInitialize(""), declare Scorm_API_12 function like this:
function Scorm_API_12() {
var Initialized = false;
this.LMSInitialize = function(param) {
errorCode = "0";
if (param == "") {
if (!Initialized) {
Initialized = true;
errorCode = "0";
return "true";
} else {
errorCode = "101";
}
} else {
errorCode = "201";
}
return "false";
}
// some more functions, omitted.
}
var API = new Scorm_API_12();
"git pull" or "git merge" between master and development branches
If you are not sharing develop branch with anybody, then I would just rebase it every time master updated, that way you will not have merge commits all over your history once you will merge develop back into master. Workflow in this case would be as follows:
> git clone git://<remote_repo_path>/ <local_repo>
> cd <local_repo>
> git checkout -b develop
....do a lot of work on develop
....do all the commits
> git pull origin master
> git rebase master develop
Above steps will ensure that your develop branch will be always on top of the latest changes from the master branch. Once you are done with develop branch and it's rebased to the latest changes on master you can just merge it back:
> git checkout -b master
> git merge develop
> git branch -d develop
Length of array in function argument
First, a better usage to compute number of elements when the actual array declaration is in scope is:
sizeof array / sizeof array[0]
This way you don't repeat the type name, which of course could change in the declaration and make you end up with an incorrect length computation. This is a typical case of don't repeat yourself.
Second, as a minor point, please note that sizeof is not a function, so the expression above doesn't need any parenthesis around the argument to sizeof.
Third, C doesn't have references so your usage of & in a declaration won't work.
I agree that the proper C solution is to pass the length (using the size_t type) as a separate argument, and use sizeof at the place the call is being made if the argument is a "real" array.
Note that often you work with memory returned by e.g. malloc(), and in those cases you never have a "true" array to compute the size off of, so designing the function to use an element count is more flexible.
MySQL root access from all hosts
MYSQL 8.0 - open mysql command line client
GRANT ALL PRIVILEGES ON \*.* TO 'root'@'localhost';
use mysql
UPDATE mysql.user SET host='%' WHERE user='root';
Restart mysql service
Get image dimensions
You can use the getimagesize function like this:
list($width, $height) = getimagesize('path to image');
echo "width: " . $width . "<br />";
echo "height: " . $height;
Java 8 lambda Void argument
You can create a sub-interface for that special case:
interface Command extends Action<Void, Void> {
default Void execute(Void v) {
execute();
return null;
}
void execute();
}
It uses a default method to override the inherited parameterized method Void execute(Void), delegating the call to the simpler method void execute().
The result is that it's much simpler to use:
Command c = () -> System.out.println("Do nothing!");
Calculate MD5 checksum for a file
This is how I do it:
using System.IO;
using System.Security.Cryptography;
public string checkMD5(string filename)
{
using (var md5 = MD5.Create())
{
using (var stream = File.OpenRead(filename))
{
return Encoding.Default.GetString(md5.ComputeHash(stream));
}
}
}
sass :first-child not working
I think that it is better (for my expirience) to use: :first-of-type, :nth-of-type(), :last-of-type. It can be done whit a little changing of rules, but I was able to do much more than whit *-of-type, than *-child selectors.
Palindrome check in Javascript
I've added some more to the above functions, to check strings like, "Go hang a salami, I'm a lasagna hog".
function checkPalindrom(str) {
var str = str.replace(/[^a-zA-Z0-9]+/gi, '').toLowerCase();
return str == str.split('').reverse().join('');
}
Thanks
How to check whether a int is not null or empty?
An integer can't be null but there is a really simple way of doing what you want to do. Use an if-then statement in which you check the integer's value against all possible values.
Example:
int x;
// Some Code...
if (x <= 0 || x > 0){
// What you want the code to do if x has a value
} else {
// What you want the code to do if x has no value
}
Disclaimer:
I am assuming that Java does not automatically set values of numbers to 0 if it doesn't see a value.
Find location of a removable SD card
Since my original answer above, scanning vold is no longer viable across the various manufacturers.
I've developed a more reliable and straight forward method.
File mnt = new File("/storage");
if (!mnt.exists())
mnt = new File("/mnt");
File[] roots = mnt.listFiles(new FileFilter() {
@Override
public boolean accept(File pathname) {
return pathname.isDirectory() && pathname.exists()
&& pathname.canWrite() && !pathname.isHidden()
&& !isSymlink(pathname);
}
});
roots will contain all the writeable root directories on the system, including any usb connected usb devices.
NOTE: The canWrite method needs the android.permission.WRITE_EXTERNAL_STORAGE permission.
How to animate button in android?
Class.Java
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_with_the_button);
final Animation myAnim = AnimationUtils.loadAnimation(this, R.anim.milkshake);
Button myButton = (Button) findViewById(R.id.new_game_btn);
myButton.setAnimation(myAnim);
}
For onClick of the Button
myButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
v.startAnimation(myAnim);
}
});
Create the anim folder in res directory
Right click on, res -> New -> Directory
Name the new Directory anim
create a new xml file name it milkshake
milkshake.xml
<?xml version="1.0" encoding="utf-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:duration="100"
android:fromDegrees="-5"
android:pivotX="50%"
android:pivotY="50%"
android:repeatCount="10"
android:repeatMode="reverse"
android:toDegrees="5" />
asp.net Button OnClick event not firing
I had the same problem, my aspnet button's click was not firing. It turns out that some where on other part of the page has an input with html "required" attribute on.
This might be sound strange, but once I remove the required attribute, the button just works normally.
Parsing JSON giving "unexpected token o" error
Your data is already an object. No need to parse it. The javascript interpreter has already parsed it for you.
var cur_ques_details ={"ques_id":15,"ques_title":"jlkjlkjlkjljl"};
document.write(cur_ques_details['ques_title']);
Why doesn't logcat show anything in my Android?
While the answer provided by MoMo will resolve the problem temporarily it will most likely reoccur the next time you launch Eclipse, or launch on a different Emulator/Device.
Instead of always having to select my device in the devices view I've found a better solution is to go into your Eclipse preferences and navigate to Android -> LogCat in the list on the left and then enable "Monitor logcat for messages from applications in workspace".
This way no matter what device you are using logcat will automatically start showing output from it as soon as the application launches.
It will also setup a filter that ensures that only output from your application is displayed, which you can reuse / disable as needed.
java.net.BindException: Address already in use: JVM_Bind <null>:80
Use the following command to find if your tomcat port is already in use,
netstat -a -b
netstat -a -o | findstr :port
For example
netstat -a -o | findstr :8080
Exception:
java.net.BindException: Address already in use: JVM_Bind:80
means that port 80 is configured by your Tomcat server and it is already used by some other application running on your computer. Please quit Skype if open or change the default port in Skype or other application's port to something other than 80. Or change the tomcat port to something else than 80(e.g. 8080 or 9090) in the server.xml file under the config folder of your tomcat installation directory.
Exception:
java.net.BindException: Address already in use: JVM_Bind
means you din't stop the tomcat server properly and you are trying to start the server again. In Eclipse, the solution for me was to remove the project from the servers tab and right click and run the project as Run on server. This added the project back to the Tomcat 7 and I din't get the BindException error. This was due to closing eclipse the last time you used without stopping the Tomcat server.
How can I see the specific value of the sql_mode?
You can also try this to determine the current global sql_mode value:
SELECT @@GLOBAL.sql_mode;
or session sql_mode value:
SELECT @@SESSION.sql_mode;
I also had the feeling that the SQL mode was indeed empty.
200 PORT command successful. Consider using PASV. 425 Failed to establish connection
Try using the passive command before using ls.
From FTP client, to check if the FTP server supports passive mode, after login, type quote PASV.
Following are connection examples to a vsftpd server with passive mode on and off
vsftpd with pasv_enable=NO:
# ftp localhost
Connected to localhost.localdomain.
220 (vsFTPd 2.3.5)
Name (localhost:john): anonymous
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> quote PASV
550 Permission denied.
ftp>
vsftpd with pasv_enable=YES:
# ftp localhost
Connected to localhost.localdomain.
220 (vsFTPd 2.3.5)
Name (localhost:john): anonymous
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> quote PASV
227 Entering Passive Mode (127,0,0,1,173,104).
ftp>
How to log request and response body with Retrofit-Android?
I hope this code will help you to logging .
you just need to add interceptor in your Build.Gradle then make RetrofitClient .
First Step
Add this line to your build.gradle
implementation 'com.squareup.okhttp3:logging-interceptor:3.4.1'
Second Step
Make your Retrofit Client
public class RetrofitClient {
private Retrofit retrofit;
private static OkHttpClient.Builder httpClient =
new OkHttpClient.Builder();
private static RetrofitClient instance = null;
private static ApiServices service = null;
private static HttpLoggingInterceptor logging =
new HttpLoggingInterceptor();
private RetrofitClient(final Context context) {
httpClient.interceptors().add(new Interceptor() {
@Override
public okhttp3.Response intercept(Interceptor.Chain chain) throws IOException {
Request originalRequest = chain.request();
Request.Builder builder = originalRequest.newBuilder().
method(originalRequest.method(), originalRequest.body());
okhttp3.Response response = chain.proceed(builder.build());
/*
Do what you want
*/
return response;
}
});
if (BuildConfig.DEBUG) {
logging.setLevel(HttpLoggingInterceptor.Level.BODY);
// add logging as last interceptor
httpClient.addInterceptor(logging);
}
retrofit = new Retrofit.Builder().client(httpClient.build()).
baseUrl(Constants.BASE_URL).
addConverterFactory(GsonConverterFactory.create()).build();
service = retrofit.create(ApiServices.class);
}
public static RetrofitClient getInstance(Context context) {
if (instance == null) {
instance = new RetrofitClient(context);
}
return instance;
}
public ApiServices getApiService() {
return service;
}
}
Calling
RetrofitClient.getInstance(context).getApiService().yourRequestCall();
How to change button color with tkinter
Another way to change color of a button if you want to do multiple operations along with color change. Using the Tk().after method and binding a change method allows you to change color and do other operations.
Label.destroy is another example of the after method.
def export_win():
//Some Operation
orig_color = export_finding_graph.cget("background")
export_finding_graph.configure(background = "green")
tt = "Exported"
label = Label(tab1_closed_observations, text=tt, font=("Helvetica", 12))
label.grid(row=0,column=0,padx=10,pady=5,columnspan=3)
def change(orig_color):
export_finding_graph.configure(background = orig_color)
tab1_closed_observations.after(1000, lambda: change(orig_color))
tab1_closed_observations.after(500, label.destroy)
export_finding_graph = Button(tab1_closed_observations, text='Export', command=export_win)
export_finding_graph.grid(row=6,column=4,padx=70,pady=20,sticky='we',columnspan=3)
You can also revert to the original color.
How to decrypt Hash Password in Laravel
Short answer is that you don't 'decrypt' the password (because it's not encrypted - it's hashed).
The long answer is that you shouldn't send the user their password by email, or any other way. If the user has forgotten their password, you should send them a password reset email, and allow them to change their password on your website.
Laravel has most of this functionality built in (see the Laravel documentation - I'm not going to replicate it all here. Also available for versions 4.2 and 5.0 of Laravel).
For further reading, check out this 'blogoverflow' post: Why passwords should be hashed.
Error: Microsoft Visual C++ 10.0 is required (Unable to find vcvarsall.bat) when running Python script
I was able to fix this on Windows 7 64-bit running Python 3.4.3 by running the set command at a command prompt to determine the existing Visual Studio tools environment variable; in my case it was VS140COMNTOOLS for Visual Studio Community 2015.
Then run the following (substituting the variable on the right-hand side if yours has a different name):
set VS100COMNTOOLS=%VS140COMNTOOLS%
This allowed me to install the PyCrypto module that was previously giving me the same error as the OP.
For a more permanent solution, add this environment variable to your Windows environment via Control Panel ("Edit the system environment variables"), though you might need to use the actual path instead of the variable substitution.
Matplotlib scatterplot; colour as a function of a third variable
There's no need to manually set the colors. Instead, specify a grayscale colormap...
import numpy as np
import matplotlib.pyplot as plt
# Generate data...
x = np.random.random(10)
y = np.random.random(10)
# Plot...
plt.scatter(x, y, c=y, s=500)
plt.gray()
plt.show()
Or, if you'd prefer a wider range of colormaps, you can also specify the cmap kwarg to scatter. To use the reversed version of any of these, just specify the "_r" version of any of them. E.g. gray_r instead of gray. There are several different grayscale colormaps pre-made (e.g. gray, gist_yarg, binary, etc).
import matplotlib.pyplot as plt
import numpy as np
# Generate data...
x = np.random.random(10)
y = np.random.random(10)
plt.scatter(x, y, c=y, s=500, cmap='gray')
plt.show()
How to use curl in a shell script?
Firstly, your example is looking quite correct and works well on my machine. You may go another way.
curl $CURLARGS $RVMHTTP > ./install.sh
All output now storing in ./install.sh file, which you can edit and execute.
Maven with Eclipse Juno
This is what I was getting when tried to install m2e from Eclipse Market place.
I am using Eclipse Juno.
Cannot complete the install because one or more required items could not be found.
Software being installed: m2e - Maven Integration for Eclipse (includes Incubating components) 1.5.0.20140606-0033 (org.eclipse.m2e.feature.feature.group 1.5.0.20140606-0033)
Missing requirement: Maven Integration for Eclipse 1.5.0.20140606-0033 (org.eclipse.m2e.core 1.5.0.20140606-0033) requires 'bundle com.google.guava [14.0.1,16.0.0)' but it could not be found
Cannot satisfy dependency:
From: m2e - Maven Integration for Eclipse (includes Incubating components) 1.5.0.20140606-0033 (org.eclipse.m2e.feature.feature.group 1.5.0.20140606-0033)
To: org.eclipse.m2e.core [1.5.0.20140606-0033]
However, the below links is perfect, it works for me.
http://marketplace.eclipse.org/content/maven-integration-eclipse-wtp-juno-0
Regards,
Bilal
What is the python keyword "with" used for?
Explanation from the Preshing on Programming blog:
It’s handy when you have two related operations which you’d like to
execute as a pair, with a block of code in between. The classic
example is opening a file, manipulating the file, then
closing it:
with open('output.txt', 'w') as f:
f.write('Hi there!')
The above with statement will automatically close the file after the
nested block of code. (Continue reading to see exactly how the close
occurs.) The advantage of using a with statement is that it is
guaranteed to close the file no matter how the nested block exits. If
an exception occurs before the end of the block, it will close the
file before the exception is caught by an outer exception handler. If
the nested block were to contain a return statement, or a continue or
break statement, the with statement would automatically close the file
in those cases, too.
Update Git submodule to latest commit on origin
In my case, I wanted git to update to the latest and at the same time re-populate any missing files.
The following restored the missing files (thanks to --force which doesn't seem to have been mentioned here), but it didn't pull any new commits:
git submodule update --init --recursive --force
This did:
git submodule update --recursive --remote --merge --force
