Default FirebaseApp is not initialized
It seems that google-services:4.1.0 has an issue. Either downgrade it to
classpath 'com.google.gms:google-services:4.0.0'
or upgrade it to
classpath 'com.google.gms:google-services:4.2.0'
dependencies {
classpath 'com.android.tools.build:gradle:3.3.0-alpha08'
classpath 'com.google.gms:google-services:4.2.0'
/*classpath 'com.google.gms:google-services:4.1.0' <-- this was the problem */
}
Hope it helps
How do I remove diacritics (accents) from a string in .NET?
I needed something that converts all major unicode characters and the voted answer leaved a few out so I've created a version of CodeIgniter's convert_accented_characters($str) into C# that is easily customisable:
using System;
using System.Text;
using System.Collections.Generic;
public static class Strings
{
static Dictionary<string, string> foreign_characters = new Dictionary<string, string>
{
{ "äæ?", "ae" },
{ "öœ", "oe" },
{ "ü", "ue" },
{ "Ä", "Ae" },
{ "Ü", "Ue" },
{ "Ö", "Oe" },
{ "ÀÁÂÃÄÅ?AAAA??????????????", "A" },
{ "àáâãå?aaaaªa??????????????", "a" },
{ "?", "B" },
{ "?", "b" },
{ "ÇCCCC", "C" },
{ "çcccc", "c" },
{ "?", "D" },
{ "?", "d" },
{ "ÐDÐ?", "Dj" },
{ "ðddd", "dj" },
{ "ÈÉÊËEEEEE????????????", "E" },
{ "èéêëeeeee?e??????????", "e" },
{ "?", "F" },
{ "?", "f" },
{ "GGGGG??", "G" },
{ "gggg???", "g" },
{ "HH", "H" },
{ "hh", "h" },
{ "ÌÍÎÏIIIIII?????????", "I" },
{ "ìíîïiiiiii??????????", "i" },
{ "J", "J" },
{ "j", "j" },
{ "K??", "K" },
{ "k??", "k" },
{ "LLL?L??", "L" },
{ "lll?l??", "l" },
{ "?", "M" },
{ "?", "m" },
{ "ÑNNN??", "N" },
{ "ñnnn???", "n" },
{ "ÒÓÔÕOOOOOØ???O??????????????", "O" },
{ "òóôõoooooø?º?????????????????", "o" },
{ "?", "P" },
{ "?", "p" },
{ "RRR??", "R" },
{ "rrr??", "r" },
{ "SSS?ŠS?", "S" },
{ "sss?š?s??", "s" },
{ "?TTTt?", "T" },
{ "?ttt?", "t" },
{ "ÙÚÛUUUUUUUUUUUUU????????", "U" },
{ "ùúûuuuuuuuuuuuu???????????", "u" },
{ "ÝŸY????????", "Y" },
{ "ýÿy?????", "y" },
{ "?", "V" },
{ "?", "v" },
{ "W", "W" },
{ "w", "w" },
{ "ZZŽ??", "Z" },
{ "zzž??", "z" },
{ "Æ?", "AE" },
{ "ß", "ss" },
{ "?", "IJ" },
{ "?", "ij" },
{ "Œ", "OE" },
{ "ƒ", "f" },
{ "?", "ks" },
{ "p", "p" },
{ "ß", "v" },
{ "µ", "m" },
{ "?", "ps" },
{ "?", "Yo" },
{ "?", "yo" },
{ "?", "Ye" },
{ "?", "ye" },
{ "?", "Yi" },
{ "?", "Zh" },
{ "?", "zh" },
{ "?", "Kh" },
{ "?", "kh" },
{ "?", "Ts" },
{ "?", "ts" },
{ "?", "Ch" },
{ "?", "ch" },
{ "?", "Sh" },
{ "?", "sh" },
{ "?", "Shch" },
{ "?", "shch" },
{ "????", "" },
{ "?", "Yu" },
{ "?", "yu" },
{ "?", "Ya" },
{ "?", "ya" },
};
public static char RemoveDiacritics(this char c){
foreach(KeyValuePair<string, string> entry in foreign_characters)
{
if(entry.Key.IndexOf (c) != -1)
{
return entry.Value[0];
}
}
return c;
}
public static string RemoveDiacritics(this string s)
{
//StringBuilder sb = new StringBuilder ();
string text = "";
foreach (char c in s)
{
int len = text.Length;
foreach(KeyValuePair<string, string> entry in foreign_characters)
{
if(entry.Key.IndexOf (c) != -1)
{
text += entry.Value;
break;
}
}
if (len == text.Length) {
text += c;
}
}
return text;
}
}
Usage
// for strings
"crème brûlée".RemoveDiacritics (); // creme brulee
// for chars
"Ã"[0].RemoveDiacritics (); // A
Select Multiple Fields from List in Linq
Anonymous types allow you to select arbitrary fields into data structures that are strongly typed later on in your code:
var cats = listObject
.Select(i => new { i.category_id, i.category_name })
.Distinct()
.OrderByDescending(i => i.category_name)
.ToArray();
Since you (apparently) need to store it for later use, you could use the GroupBy operator:
Data[] cats = listObject
.GroupBy(i => new { i.category_id, i.category_name })
.OrderByDescending(g => g.Key.category_name)
.Select(g => g.First())
.ToArray();
Skipping every other element after the first
def skip_elements(elements):
new_list = []
for index,element in enumerate(elements):
if index == 0:
new_list.append(element)
elif (index % 2) == 0:
new_list.append(element)
return new_list
Also can use for loop + enumerate.
elif (index % 2) == 0: ## Checking if number is even, not odd cause indexing starts from zero not 1.
Android SQLite Example
The following Links my help you
1. Android Sqlite Database
2. Tutorial 1
Database Helper Class:
A helper class to manage database creation and version management.
You create a subclass implementing onCreate(SQLiteDatabase), onUpgrade(SQLiteDatabase, int, int) and optionally onOpen(SQLiteDatabase), and this class takes care of opening the database if it exists, creating it if it does not, and upgrading it as necessary. Transactions are used to make sure the database is always in a sensible state.
This class makes it easy for ContentProvider implementations to defer opening and upgrading the database until first use, to avoid blocking application startup with long-running database upgrades.
You need more refer this link Sqlite Helper
Inserting data to table (mysqli insert)
Okay, of course the question has been answered, but no-one seems to notice the third line of your code. It continuosly bugged me.
<?php
mysqli_connect("localhost","root","","web_table");
mysql_select_db("web_table") or die(mysql_error());
for some reason, you made a mysqli connection to server, but you are trying to make a mysql connection to database.To get going, rather use
$link = mysqli_connect("localhost","root","","web_table");
mysqli_select_db ($link , "web_table" ) or die.....
or for where i began
<?php $connection = mysqli_connect("localhost","root","","web_table");
global $connection; // global connection to databases - kill it once you're done
or just query with a $connection parameter as the other argument like above. Get rid of that third line.
Folder structure for a Node.js project
Assuming we are talking about web applications and building APIs:
One approach is to categorize files by feature, much like what a micro service architecture would look like. The biggest win in my opinion is that it is super easy to see which files relate to a feature of the application.
The best way to illustrate is through an example:
We are developing a library application. In the first version of the application, a user can:
- Search for books and see metadata of books
- Search for authors and see their books
In a second version, users can also:
- Create an account and log in
- Loan/borrow books
In a third version, users can also:
- Save a list of books they want to read/mark favorites
First we have the following structure:
books
+- controllers
¦ +- booksController.js
¦ +- authorsController.js
¦
+- entities
+- book.js
+- author.js
We then add on the user and loan features:
user
+- controllers
¦ +- userController.js
+- entities
¦ +- user.js
+- middleware
+- authentication.js
loan
+- controllers
¦ +- loanController.js
+- entities
+- loan.js
And then the favorites functionality:
favorites
+- controllers
¦ +- favoritesController.js
+- entities
+- favorite.js
For any new developer that gets handed the task to add on that the books search should also return information if any book have been marked as favorite, it's really easy to see where in the code he/she should look.
Then when the product owner sweeps in and exclaims that the favorites feature should be removed completely, it's easy to remove it.
How to set recurring schedule for xlsm file using Windows Task Scheduler
Better to use a vbs as you indicated
- Create a simple
vbs, which is a text file with a .vbs extension (see sample code below)
- Use the Task Scheduler to run the
vbs
- Use the
vbs to open the workbook at the scheduled time and then either:
- use the
Private Sub Workbook_Open() event in the ThisWorkbook module to run code when the file is opened
- more robustly (as macros may be disabled on open), use
Application.Run in the vbs to run the macro
See this example of the later approach at Running Excel on Windows Task Scheduler
sample vbs
Dim ObjExcel, ObjWB
Set ObjExcel = CreateObject("excel.application")
'vbs opens a file specified by the path below
Set ObjWB = ObjExcel.Workbooks.Open("C:\temp\rod.xlsm")
'either use the Workbook Open event (if macros are enabled), or Application.Run
ObjWB.Close False
ObjExcel.Quit
Set ObjExcel = Nothing
C error: undefined reference to function, but it IS defined
I think the problem is that when you're trying to compile testpoint.c, it includes point.h but it doesn't know about point.c. Since point.c has the definition for create, not having point.c will cause the compilation to fail.
I'm not familiar with MinGW, but you need to tell the compiler to look for point.c. For example with gcc you might do this:
gcc point.c testpoint.c
As others have pointed out, you also need to remove one of your main functions, since you can only have one.
Using .Select and .Where in a single LINQ statement
Did you add the Select() after the Where() or before?
You should add it after, because of the concurrency logic:
1 Take the entire table
2 Filter it accordingly
3 Select only the ID's
4 Make them distinct.
If you do a Select first, the Where clause can only contain the ID attribute because all other attributes have already been edited out.
Update: For clarity, this order of operators should work:
db.Items.Where(x=> x.userid == user_ID).Select(x=>x.Id).Distinct();
Probably want to add a .toList() at the end but that's optional :)
How do I get the picture size with PIL?
You can use Pillow (Website, Documentation, GitHub, PyPI). Pillow has the same interface as PIL, but works with Python 3.
Installation
$ pip install Pillow
If you don't have administrator rights (sudo on Debian), you can use
$ pip install --user Pillow
Other notes regarding the installation are here.
Code
from PIL import Image
with Image.open(filepath) as img:
width, height = img.size
Speed
This needed 3.21 seconds for 30336 images (JPGs from 31x21 to 424x428, training data from National Data Science Bowl on Kaggle)
This is probably the most important reason to use Pillow instead of something self-written. And you should use Pillow instead of PIL (python-imaging), because it works with Python 3.
Alternative #1: Numpy (deprecated)
I keep scipy.ndimage.imread as the information is still out there, but keep in mind:
imread is deprecated! imread is deprecated in SciPy 1.0.0, and [was] removed in 1.2.0.
import scipy.ndimage
height, width, channels = scipy.ndimage.imread(filepath).shape
Alternative #2: Pygame
import pygame
img = pygame.image.load(filepath)
width = img.get_width()
height = img.get_height()
Eclipse: Frustration with Java 1.7 (unbound library)
To set JDK you can watch this video : how to set JDK
. Then when you'll have JDK:
- Right click on build path and select "Build Path"
- Choose "Configure Build Path"
- Click on "JRE System Library [JavaSE-1.7] (unbound)"
- Edit it
- Choose "Alternate JRE"
- Click on "Installed JREs.." button
- Press Add
- Choose to add "Standard VM"
- Choose JRE Home directory - usually it is locates in "C:\Program Files\Java\jre7" directory
- Press "Finish"
- Re-check newly appeared "Jre7": Verify that now when you edit "JRE System Library [JavaSE-1.7]" "Alternate JRE" is chosen for jre7.
bypass invalid SSL certificate in .net core
Came here looking for an answer to the same problem, but I'm using WCF for NET Core. If you're in the same boat, use:
client.ClientCredentials.ServiceCertificate.SslCertificateAuthentication =
new X509ServiceCertificateAuthentication()
{
CertificateValidationMode = X509CertificateValidationMode.None,
RevocationMode = X509RevocationMode.NoCheck
};
How do I remove duplicate items from an array in Perl?
Try this, seems the uniq function needs a sorted list to work properly.
use strict;
# Helper function to remove duplicates in a list.
sub uniq {
my %seen;
grep !$seen{$_}++, @_;
}
my @teststrings = ("one", "two", "three", "one");
my @filtered = uniq @teststrings;
print "uniq: @filtered\n";
my @sorted = sort @teststrings;
print "sort: @sorted\n";
my @sortedfiltered = uniq sort @teststrings;
print "uniq sort : @sortedfiltered\n";
How do you create nested dict in Python?
UPDATE: For an arbitrary length of a nested dictionary, go to this answer.
Use the defaultdict function from the collections.
High performance: "if key not in dict" is very expensive when the data set is large.
Low maintenance: make the code more readable and can be easily extended.
from collections import defaultdict
target_dict = defaultdict(dict)
target_dict[key1][key2] = val
How can I fill a div with an image while keeping it proportional?
It's a bit late but I just had the same problem and finally solved it with the help of another stackoverflow post (https://stackoverflow.com/a/29103071).
img {
object-fit: cover;
width: 50px;
height: 100px;
}
Hope this still helps somebody.
Ps: Also works together with max-height, max-width, min-width and min-height css properties. It's espacially handy with using lenght units like 100% or 100vh/100vw to fill the container or the whole browser window.
How to enable mbstring from php.ini?
All XAMPP packages come with Multibyte String (php_mbstring.dll) extension installed.
If you have accidentally removed DLL file from php/ext folder, just add it back (get the copy from XAMPP zip archive - its downloadable).
If you have deleted the accompanying INI configuration line from php.ini file, add it back as well:
extension=php_mbstring.dll
Also, ensure to restart your webserver (Apache) using XAMPP control panel.
Additional Info on Enabling PHP Extensions
- install extension (e.g. put php_mbstring.dll into
/XAMPP/php/ext directory)
- in php.ini, ensure extension directory specified (e.g.
extension_dir = "ext")
- ensure correct build of DLL file (e.g. 32bit thread-safe VC9 only works with DLL files built using exact same tools and configuration: 32bit thread-safe VC9)
- ensure PHP API versions match (If not, once you restart the webserver you will receive related error.)
AngularJS - Trigger when radio button is selected
i prefer to use ng-value with ng-if,
[ng-value] will handle trigger changes
<input type="radio" name="isStudent" ng-model="isStudent" ng-value="true" />
//to show and hide input by removing it from the DOM, that's make me secure from malicious data
<input type="text" ng-if="isStudent" name="textForStudent" ng-model="job">
Retrieving Android API version programmatically
Very easy:
String manufacturer = Build.MANUFACTURER;
String model = Build.MODEL;
int version = Build.VERSION.SDK_INT;
String versionRelease = Build.VERSION.RELEASE;
Log.e("MyActivity", "manufacturer " + manufacturer
+ " \n model " + model
+ " \n version " + version
+ " \n versionRelease " + versionRelease
);
Output:
E/MyActivity: manufacturer ManufacturerX
model SM-T310
version 19
versionRelease 4.4.2
Jquery Date picker Default Date
interesting, datepicker default date is current date as I found,
but you can set date by
$("#yourinput").datepicker( "setDate" , "7/11/2011" );
don't forget to check you system date :)
How do I delay a function call for 5 seconds?
You can use plain javascript, this will call your_func once, after 5 seconds:
setTimeout(function() { your_func(); }, 5000);
If your function has no parameters and no explicit receiver you can call directly setTimeout(func, 5000)
There is also a plugin I've used once. It has oneTime and everyTime methods.
How to check if a value exists in a dictionary (python)
Python dictionary has get(key) function
>>> d.get(key)
For Example,
>>> d = {'1': 'one', '3': 'three', '2': 'two', '5': 'five', '4': 'four'}
>>> d.get('3')
'three'
>>> d.get('10')
None
If your key does'nt exist, will return None value.
foo = d[key] # raise error if key doesn't exist
foo = d.get(key) # return None if key doesn't exist
Content relevant to versions less than 3.0 and greater than 5.0.
.
How can I add new item to the String array?
From arrays
An array is a container object that holds a fixed number of values of a single type. The length of an array is established when the array is created. After creation, its length is fixed. You've seen an example of arrays already, in the main method of the "Hello World!" application. This section discusses arrays in greater detail.
So in the case of a String array, once you create it with some length, you can't modify it,
but you can add elements until you fill it.
String[] arr = new String[10]; // 10 is the length of the array.
arr[0] = "kk";
arr[1] = "pp";
...
So if your requirement is to add many objects, it's recommended that you use Lists like:
List<String> a = new ArrayList<String>();
a.add("kk");
a.add("pp");
Posting a File and Associated Data to a RESTful WebService preferably as JSON
Please ensure that you have following import. Ofcourse other standard imports
import org.springframework.core.io.FileSystemResource
void uploadzipFiles(String token) {
RestBuilder rest = new RestBuilder(connectTimeout:10000, readTimeout:20000)
def zipFile = new File("testdata.zip")
def Id = "001G00000"
MultiValueMap<String, String> form = new LinkedMultiValueMap<String, String>()
form.add("id", id)
form.add('file',new FileSystemResource(zipFile))
def urld ='''http://URL''';
def resp = rest.post(urld) {
header('X-Auth-Token', clientSecret)
contentType "multipart/form-data"
body(form)
}
println "resp::"+resp
println "resp::"+resp.text
println "resp::"+resp.headers
println "resp::"+resp.body
println "resp::"+resp.status
}
Do I need <class> elements in persistence.xml?
Not sure if you're doing something similar to what I am doing, but Im generating a load of source java from an XSD using JAXB in a seperate component using Maven. Lets say this artifact is called "base-model"
I wanted to import this artifact containing the java source and run hibernate over all classes in my "base-model" artifact jar and not specify each explicitly. Im adding "base-model" as a dependency for my hibernate component but the trouble is the tag in persistence.xml only allows you to specify absolute paths.
The way I got round it is to copy my "base-model" jar dependency explictly to my target dir and also strip the version of it. So whereas if I build my "base-model" artifact it generate "base-model-1.0-SNAPSHOT.jar", the copy-resources step copies it as "base-model.jar".
So in your pom for the hibernate component:
<!-- We want to copy across all our artifacts containing java code
generated from our scheams. We copy them across and strip the version
so that our persistence.xml can reference them directly in the tag
<jar-file>target/dependency/${artifactId}.jar</jar-file> -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.5.1</version>
<executions>
<execution>
<id>copy-dependencies</id>
<phase>process-resources</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
</execution>
</executions>
<configuration>
<includeArtifactIds>base-model</includeArtifactIds>
<stripVersion>true</stripVersion>
</configuration>
</plugin>
Then I call the hibernate plugin in the next phase "process-classes":
<!-- Generate the schema DDL -->
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>hibernate3-maven-plugin</artifactId>
<version>2.2</version>
<executions>
<execution>
<id>generate-ddl</id>
<phase>process-classes</phase>
<goals>
<goal>hbm2ddl</goal>
</goals>
</execution>
</executions>
<configuration>
<components>
<component>
<name>hbm2java</name>
<implementation>annotationconfiguration</implementation>
<outputDirectory>/src/main/java</outputDirectory>
</component>
</components>
<componentProperties>
<persistenceunit>mysql</persistenceunit>
<implementation>jpaconfiguration</implementation>
<create>true</create>
<export>false</export>
<drop>true</drop>
<outputfilename>mysql-schema.sql</outputfilename>
</componentProperties>
</configuration>
</plugin>
and finally in my persistence.xml I can explicitly set the location of the jar thus:
<jar-file>target/dependency/base-model.jar</jar-file>
and add the property:
<property name="hibernate.archive.autodetection" value="class, hbm"/>
How to uninstall a package installed with pip install --user
I strongly recommend you to use virtual environments for python package installation. With virtualenv, you prevent any package conflict and total isolation from your python related userland commands.
To delete all your package follow this;
It's possible to uninstall packages installed with --user flag. This one worked for me;
pip freeze --user | xargs pip uninstall -y
For python 3;
pip3 freeze --user | xargs pip3 uninstall -y
But somehow these commands don't uninstall setuptools and pip. After those commands (if you really want clean python) you may delete them with;
pip uninstall setuptools && pip uninstall pip
How to get item count from DynamoDB?
In Scala:
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClientBuilder
import com.amazonaws.services.dynamodbv2.document.DynamoDB
val client = AmazonDynamoDBClientBuilder.standard().build()
val dynamoDB = new DynamoDB(client)
val tableDescription = dynamoDB.getTable("table name").describe().getItemCount()
Android java.lang.NoClassDefFoundError
After Checking Java Build Path, Then add lines of code in manifest file.
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
Read next word in java
you're better off reading a line and then doing a split.
File file = new File("path/to/file");
String words[]; // I miss C
String line;
HashMap<String, String> hm = new HashMap<>();
try (BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(file), "UTF-8")))
{
while((line = br.readLine() != null)){
words = line.split("\\s");
if (hm.containsKey(words[0])){
System.out.println("Found duplicate ... handle logic");
}
hm.put(words[0],words[1]); //if index==0 is ur key
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
Received fatal alert: handshake_failure through SSLHandshakeException
To troubleshoot from developer (item 1) and system admin (item 2 and 3) perspective:
- Enable SSL handshake debug at Java via
-Djavax.net.debug=ssl:handshake:verbose.
- Install ssldump at server via
sudo apt install ssldump or compile from source by following this link if you observe Unknown value in cipher when you run below step.
- At server,
sudo ssldump -k <your-private-key> -i <your-network-interface>
- Check the log about real reason of the failure.
Example of not working handshake of ssldump log:
New TCP connection #1: 10.1.68.86(45308) <-> 10.1.68.83(5671)
1 1 0.0111 (0.0111) C>S Handshake
ClientHello
Version 3.3
cipher suites
TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
TLS_RSA_WITH_AES_256_GCM_SHA384
TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384
TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384
TLS_DHE_RSA_WITH_AES_256_GCM_SHA384
TLS_DHE_DSS_WITH_AES_256_GCM_SHA384
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
TLS_RSA_WITH_AES_128_GCM_SHA256
TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256
TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256
TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
TLS_DHE_DSS_WITH_AES_128_GCM_SHA256
TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384
TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384
TLS_RSA_WITH_AES_256_CBC_SHA256
TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384
TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384
TLS_DHE_RSA_WITH_AES_256_CBC_SHA256
TLS_DHE_DSS_WITH_AES_256_CBC_SHA256
TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA
TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA
TLS_RSA_WITH_AES_256_CBC_SHA
TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA
TLS_ECDH_RSA_WITH_AES_256_CBC_SHA
TLS_DHE_RSA_WITH_AES_256_CBC_SHA
TLS_DHE_DSS_WITH_AES_256_CBC_SHA
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256
TLS_RSA_WITH_AES_128_CBC_SHA256
TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256
TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256
TLS_DHE_RSA_WITH_AES_128_CBC_SHA256
TLS_DHE_DSS_WITH_AES_128_CBC_SHA256
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA
TLS_RSA_WITH_AES_128_CBC_SHA
TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA
TLS_ECDH_RSA_WITH_AES_128_CBC_SHA
TLS_DHE_RSA_WITH_AES_128_CBC_SHA
TLS_DHE_DSS_WITH_AES_128_CBC_SHA
TLS_EMPTY_RENEGOTIATION_INFO_SCSV
compression methods
NULL
1 2 0.0122 (0.0011) S>C Alert
level fatal
value insufficient_security
1 0.0126 (0.0004) S>C TCP RST
Example of successful handshake of ssldump log
New TCP connection #1: 10.1.68.86(56558) <-> 10.1.68.83(8443)
1 1 0.0009 (0.0009) C>S Handshake
ClientHello
Version 3.3
cipher suites
TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
TLS_DHE_RSA_WITH_AES_256_GCM_SHA384
Unknown value 0xcca9
Unknown value 0xcca8
Unknown value 0xccaa
TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384
TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384
TLS_DHE_RSA_WITH_AES_256_CBC_SHA256
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256
TLS_DHE_RSA_WITH_AES_128_CBC_SHA256
TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA
TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA
TLS_DHE_RSA_WITH_AES_256_CBC_SHA
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA
TLS_DHE_RSA_WITH_AES_128_CBC_SHA
TLS_RSA_WITH_AES_256_GCM_SHA384
TLS_RSA_WITH_AES_128_GCM_SHA256
TLS_RSA_WITH_AES_256_CBC_SHA256
TLS_RSA_WITH_AES_128_CBC_SHA256
TLS_RSA_WITH_AES_256_CBC_SHA
TLS_RSA_WITH_AES_128_CBC_SHA
TLS_EMPTY_RENEGOTIATION_INFO_SCSV
compression methods
NULL
1 2 0.0115 (0.0106) S>C Handshake
ServerHello
Version 3.3
session_id[0]=
cipherSuite TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
compressionMethod NULL
1 3 0.0115 (0.0000) S>C Handshake
Certificate
1 4 0.0115 (0.0000) S>C Handshake
ServerKeyExchange
Not enough data. Found 294 bytes (expecting 32767)
1 5 0.0115 (0.0000) S>C Handshake
ServerHelloDone
1 6 0.0141 (0.0025) C>S Handshake
ClientKeyExchange
Not enough data. Found 31 bytes (expecting 16384)
1 7 0.0141 (0.0000) C>S ChangeCipherSpec
1 8 0.0141 (0.0000) C>S Handshake
1 9 0.0149 (0.0008) S>C Handshake
1 10 0.0149 (0.0000) S>C ChangeCipherSpec
1 11 0.0149 (0.0000) S>C Handshake
Example of not working Java log
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.778 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.779 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.779 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.780 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_RSA_WITH_AES_256_GCM_SHA384 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.780 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.780 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.781 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.781 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_DHE_DSS_WITH_AES_256_GCM_SHA384 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.781 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.782 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_RSA_WITH_AES_128_GCM_SHA256 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.782 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.782 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.782 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.783 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_DHE_DSS_WITH_AES_128_GCM_SHA256 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.783 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.783 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.783 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_RSA_WITH_AES_256_CBC_SHA256 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.783 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.784 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.784 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: T LS_DHE_RSA_WITH_AES_256_CBC_SHA256 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.784 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_DHE_DSS_WITH_AES_256_CBC_SHA256 for TLS11
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.784 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.784 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.784 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.784 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_RSA_WITH_AES_256_GCM_SHA384 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.785 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.785 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.785 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.785 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_DHE_DSS_WITH_AES_256_GCM_SHA384 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.785 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.785 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_RSA_WITH_AES_128_GCM_SHA256 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.785 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.785 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.786 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.786 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_DHE_DSS_WITH_AES_128_GCM_SHA256 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.786 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.786 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.786 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_RSA_WITH_AES_256_CBC_SHA256 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.786 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384 for TLS10 javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.786 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.786 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_DHE_RSA_WITH_AES_256_CBC_SHA256 for TLS10
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.787 MYT|HandshakeContext.java:294|Ignore unsupported cipher suite: TLS_DHE_DSS_WITH_AES_256_CBC_SHA256 for TLS10
javax.net.ssl|WARNING|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.818 MYT|SignatureScheme.java:282|Signature algorithm, ed25519, is not supported by the underlying providers
javax.net.ssl|WARNING|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.818 MYT|SignatureScheme.java:282|Signature algorithm, ed448, is not supported by the underlying providers
javax.net.ssl|ALL|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.822 MYT|SignatureScheme.java:358|Ignore disabled signature sheme: rsa_md5
javax.net.ssl|INFO|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.822 MYT|AlpnExtension.java:161|No available application protocols
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.823 MYT|SSLExtensions.java:256|Ignore, context unavailable extension: application_layer_protocol_negotiation
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.823 MYT|SSLExtensions.java:256|Ignore, context unavailable extension: renegotiation_info
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.825 MYT|ClientHello.java:651|Produced ClientHello handshake message (
"ClientHello": {
"client version" : "TLSv1.2",
"random" : "FB BC CD 7C 17 65 86 49 3E 1C 15 37 24 94 7D E7 60 44 1B B8 F4 18 21 D0 E1 B1 31 0D E1 80 D6 A7",
"session id" : "",
"cipher suites" : "[TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384(0xC02C), TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256(0xC02B), TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384(0xC030), TLS_RSA_WITH_AES_256_GCM_SHA384(0x009D), TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384(0xC02E), TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384(0xC032), TLS_DHE_RSA_WITH_AES_256_GCM_SHA384(0x009F), TLS_DHE_DSS_WITH_AES_256_GCM_SHA384(0x00A3), TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256(0xC02F), TLS_RSA_WITH_AES_128_GCM_SHA256(0x009C), TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256(0xC02D), TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256(0xC031), TLS_DHE_RSA_WITH_AES_128_GCM_SHA256(0x009E), TLS_DHE_DSS_WITH_AES_128_GCM_SHA256(0x00A2), TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384(0xC024), TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384(0xC028), TLS_RSA_WITH_AES_256_CBC_SHA256(0x003D), TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384(0xC026), TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384(0xC02A), TLS_DHE_RSA_WITH_AES_256_CBC_SHA256(0x006B), TLS_DHE_DSS_WITH_AES_256_CBC_SHA256(0x006A), TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA(0xC00A), TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA(0xC014), TLS_RSA_WITH_AES_256_CBC_SHA(0x0035), TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA(0xC005), TLS_ECDH_RSA_WITH_AES_256_CBC_SHA(0xC00F), TLS_DHE_RSA_WITH_AES_256_CBC_SHA(0x0039), TLS_DHE_DSS_WITH_AES_256_CBC_SHA(0x0038), TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256(0xC023), TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256(0xC027), TLS_RSA_WITH_AES_128_CBC_SHA256(0x003C), TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256(0xC025), TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256(0xC029), TLS_DHE_RSA_WITH_AES_128_CBC_SHA256(0x0067), TLS_DHE_DSS_WITH_AES_128_CBC_SHA256(0x0040), TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA(0xC009), TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA(0xC013), TLS_RSA_WITH_AES_128_CBC_SHA(0x002F), TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA(0xC004), TLS_ECDH_RSA_WITH_AES_128_CBC_SHA(0xC00E), TLS_DHE_RSA_WITH_AES_128_CBC_SHA(0x0033), TLS_DHE_DSS_WITH_AES_128_CBC_SHA(0x0032), TLS_EMPTY_RENEGOTIATION_INFO_SCSV(0x00FF)]",
"compression methods" : "00", "extensions" : [
"server_name (0)": {
type=host_name (0), value=mq.tpc-ohcis.moh.gov.my
},
"status_request (5)": {
"certificate status type": ocsp
"OCSP status request": {
"responder_id": <empty>
"request extensions": {
<empty>
}
}
},
"supported_groups (10)": {
"versions": [secp256r1, secp384r1, secp521r1, sect283k1, sect283r1, sect409k1, sect409r1, sect571k1, sect571r1, secp256k1, ffdhe2048, ffdhe3072, ffdhe4096, ffdhe6144, ffdhe8192]
},
"ec_point_formats (11)": {
"formats": [uncompressed]
},
"signature_algorithms (13)": {
"signature schemes": [ecdsa_secp256r1_sha256, ecdsa_secp384r1_sha384, ecdsa_secp512r1_sha512, rsa_pss_rsae_sha256, rsa_pss_rsae_sha384, rsa_pss_rsae_sha512, rsa_pss_pss_sha256, rsa_pss_pss_sha384, rsa_pss_pss_sha512, rsa_pkcs1_sha256, rsa_pkcs1_sha384, rsa_pkcs1_sha512, dsa_sha256, ecdsa_sha224, rsa_sha224, dsa_sha224, ecdsa_sha1, rsa_pkcs1_sha1, dsa_sha1]
},
"signature_algorithms_cert (50)": {
"signature schemes": [ecdsa_secp256r1_sha256, ecdsa_secp384r1_sha384, ecdsa_secp512r1_sha512, rsa_pss_rsae_sha256, rsa_pss_rsae_sha384, rsa_pss_rsae_sha512, rsa_pss_pss_sha256, rsa_pss_pss_sha384, rsa_pss_pss_sha512, rsa_pkcs1_sha256, rsa_pkcs1_sha384, rsa_pkcs1_sha512, dsa_sha256, ecdsa_sha224, rsa_sha224, dsa_sha224, ecdsa_sha1, rsa_pkcs1_sha1, dsa_sha1]
},
"status_request_v2 (17)": {
"cert status request": {
"certificate status type": ocsp_multi
"OCSP status request": {
"responder_id": <empty>
"request extensions": {
<empty>
}
} }
},
"extended_master_secret (23)": {
<empty>
},
"supported_versions (43)": {
"versions": [TLSv1.2, TLSv1.1, TLSv1]
}
]
}
)
javax.net.ssl|DEBUG|43|SimpleAsyncTaskExecutor-1|2019-07-03 17:35:01.829 MYT|Alert.java:238|Received alert message (
"Alert": {
"level" : "fatal",
"description": "insufficient_security"
}
)
expected constructor, destructor, or type conversion before ‘(’ token
This is not only a 'newbie' scenario. I just ran across this compiler message (GCC 5.4) when refactoring a class to remove some constructor parameters. I forgot to update both the declaration and definition, and the compiler spit out this unintuitive error.
The bottom line seems to be this: If the compiler can't match the definition's signature to the declaration's signature it thinks the definition is not a constructor and then doesn't know how to parse the code and displays this error. Which is also what happened for the OP: std::string is not the same type as string so the declaration's signature differed from the definition's and this message was spit out.
As a side note, it would be nice if the compiler looked for almost-matching constructor signatures and upon finding one suggested that the parameters didn't match rather than giving this message.
How to check if MySQL returns null/empty?
You can use is_null() function.
http://php.net/manual/en/function.is-null.php : in the comments :
mdufour at gmail dot com
20-Aug-2008 04:31
Testing for a NULL field/column returned by a mySQL query.
Say you want to check if field/column “foo” from a given row of the table “bar” when > returned by a mySQL query is null.
You just use the “is_null()” function:
[connect…]
$qResult=mysql_query("Select foo from bar;");
while ($qValues=mysql_fetch_assoc($qResult))
if (is_null($qValues["foo"]))
echo "No foo data!";
else
echo "Foo data=".$qValues["foo"];
[…]
Difference between "Complete binary tree", "strict binary tree","full binary Tree"?
Consider a binary tree whose nodes are drawn in a tree fashion. Now start numbering the nodes from top to bottom and left to right. A complete tree has these properties:
If n has children then all nodes numbered less than n have two children.
If n has one child it must be the left child and all nodes less than n have two children. In addition no node numbered greater than n has children.
If n has no children then no node numbered greater than n has children.
A complete binary tree can be used to represent a heap. It can be easily represented in contiguous memory with no gaps (i.e. all array elements are used save for any space that may exist at the end).
Command failed due to signal: Segmentation fault: 11
I just had this issue and found that it was because I had accidentally left an override on a function that I'd moved from the class to a protocol (therefore the subclass was no longer overriding a function of the parent).
Android Canvas: drawing too large bitmap
In my case I had to remove the android platform and add it again. Something got stuck and copying all my code into another app worked like a charm - hence my idea of cleaning up the build for android by removing the platform.
cordova platform remove android
cordova platform add android
I guess it's some kind of cleanup that you have to do from time to time :-(
Angularjs autocomplete from $http
Use angular-ui-bootstrap's typehead.
It had great support for $http and promises.
Also, it doesn't include any JQuery at all, pure AngularJS.
(I always prefer using existing libraries and if they are missing something to open an issue or pull request, much better then creating your own again)
Convert integer into its character equivalent, where 0 => a, 1 => b, etc
The only problemo with @mikemaccana's great solution is that it uses the binary >> operator which is costly, performance-wise. I suggest this modification to his great work as a slight improvement that your colleagues can perhaps read more easily.
const getColumnName = (i) => {
const previousLetters = (i >= 26 ? getColumnName(Math.floor(i / 26) -1 ) : '');
const lastLetter = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'[i % 26];
return previousLetters + lastLetter;
}
Or as a one-liner
const getColumnName = i => (i >= 26 ? getColumnName(Math.floor(i / 26) -1 ) : '') + 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'[i % 26];
Example:
getColumnName(0); // "A"
getColumnName(1); // "B"
getColumnName(25); // "Z"
getColumnName(26); // "AA"
getColumnName(27); // "AB"
getColumnName(80085) // "DNLF"
How to download and save an image in Android
I have a simple solution which is working perfectly. The code is not mine, I found it on this link. Here are the steps to follow:
1. Before downloading the image, let’s write a method for saving bitmap into an image file in the internal storage in android. It needs a context, better to use the pass in the application context by getApplicationContext(). This method can be dumped into your Activity class or other util classes.
public void saveImage(Context context, Bitmap b, String imageName)
{
FileOutputStream foStream;
try
{
foStream = context.openFileOutput(imageName, Context.MODE_PRIVATE);
b.compress(Bitmap.CompressFormat.PNG, 100, foStream);
foStream.close();
}
catch (Exception e)
{
Log.d("saveImage", "Exception 2, Something went wrong!");
e.printStackTrace();
}
}
2. Now we have a method to save bitmap into an image file in andorid, let’s write the AsyncTask for downloading images by url. This private class need to be placed in your Activity class as a subclass. After the image is downloaded, in the onPostExecute method, it calls the saveImage method defined above to save the image. Note, the image name is hardcoded as “my_image.png”.
private class DownloadImage extends AsyncTask<String, Void, Bitmap> {
private String TAG = "DownloadImage";
private Bitmap downloadImageBitmap(String sUrl) {
Bitmap bitmap = null;
try {
InputStream inputStream = new URL(sUrl).openStream(); // Download Image from URL
bitmap = BitmapFactory.decodeStream(inputStream); // Decode Bitmap
inputStream.close();
} catch (Exception e) {
Log.d(TAG, "Exception 1, Something went wrong!");
e.printStackTrace();
}
return bitmap;
}
@Override
protected Bitmap doInBackground(String... params) {
return downloadImageBitmap(params[0]);
}
protected void onPostExecute(Bitmap result) {
saveImage(getApplicationContext(), result, "my_image.png");
}
}
3. The AsyncTask for downloading the image is defined, but we need to execute it in order to run that AsyncTask. To do so, write this line in your onCreate method in your Activity class, or in an onClick method of a button or other places you see fit.
new DownloadImage().execute("http://developer.android.com/images/activity_lifecycle.png");
The image should be saved in /data/data/your.app.packagename/files/my_image.jpeg, check this post for accessing this directory from your device.
IMO this solves the issue! If you want further steps such as load the image you can follow these extra steps:
4. After the image is downloaded, we need a way to load the image bitmap from the internal storage, so we can use it. Let’s write the method for loading the image bitmap. This method takes two paramethers, a context and an image file name, without the full path, the context.openFileInput(imageName) will look up the file at the save directory when this file name was saved in the above saveImage method.
public Bitmap loadImageBitmap(Context context, String imageName) {
Bitmap bitmap = null;
FileInputStream fiStream;
try {
fiStream = context.openFileInput(imageName);
bitmap = BitmapFactory.decodeStream(fiStream);
fiStream.close();
} catch (Exception e) {
Log.d("saveImage", "Exception 3, Something went wrong!");
e.printStackTrace();
}
return bitmap;
}
5. Now we have everything we needed for setting the image of an ImageView or any other Views that you like to use the image on. When we save the image, we hardcoded the image name as “my_image.jpeg”, now we can pass this image name to the above loadImageBitmap method to get the bitmap and set it to an ImageView.
someImageView.setImageBitmap(loadImageBitmap(getApplicationContext(), "my_image.jpeg"));
6. To get the image full path by image name.
File file = getApplicationContext().getFileStreamPath("my_image.jpeg");
String imageFullPath = file.getAbsolutePath();
7. Check if the image file exists.
File file =
getApplicationContext().getFileStreamPath("my_image.jpeg");
if (file.exists()) Log.d("file", "my_image.jpeg exists!");
To delete the image file.
File file = getApplicationContext().getFileStreamPath("my_image.jpeg");
if (file.delete()) Log.d("file", "my_image.jpeg deleted!");
how do I print an unsigned char as hex in c++ using ostream?
I have used in this way.
char strInput[] = "yourchardata";
char chHex[2] = "";
int nLength = strlen(strInput);
char* chResut = new char[(nLength*2) + 1];
memset(chResut, 0, (nLength*2) + 1);
for (int i = 0; i < nLength; i++)
{
sprintf(chHex, "%02X", strInput[i]& 0x00FF);
memcpy(&(chResut[i*2]), chHex, 2);
}
printf("\n%s",chResut);
delete chResut;
chResut = NULL;
Git vs Team Foundation Server
I think, the statement
everyone hates it except me
makes any further discussion waste: when you keep using Git, they will blame you if anything goes wrong.
Apart from this, for me Git has two advantages over a centralized VCS that I appreciate most (as partly described by Rob Sobers):
- automatic backup of the whole repo: everytime someone pulls from the central repo, he/she gets a full history of the changes. When one repo gets lost: don't worry, take one of those present on every workstation.
- offline repo access: when I'm working at home (or in an airplane or train), I can see the full history of the project, every single checkin, without starting up my VPN connection to work and can work like I were at work: checkin, checkout, branch, anything.
But as I said: I think that you're fighting a lost battle: when everyone hates Git, don't use Git. It could help you more to know why they hate Git instead of trying them to convince them.
If they simply don't want it 'cause it's new to them and are not willing to learn something new: are you sure that you will do successful development with that staff?
Does really every single person hate Git or are they influenced by some opinion leaders? Find the leaders and ask them what's the problem. Convince them and you'll convince the rest of the team.
If you cannot convince the leaders: forget about using Git, take the TFS. Will make your life easier.
Concatenate a NumPy array to another NumPy array
Well, the error message says it all: NumPy arrays do not have an append() method. There's a free function numpy.append() however:
numpy.append(M, a)
This will create a new array instead of mutating M in place. Note that using numpy.append() involves copying both arrays. You will get better performing code if you use fixed-sized NumPy arrays.
Twitter bootstrap scrollable table
None of these answers worked satisfactorily for me. They either didn't fix the table heading row in place or they required fixed column widths to work, and even then tended to have the heading row and body rows misaligned in various browsers.
I recommend biting the bullet and using a proper grid control like jsGrid or my personal favorite, SlickGrid. It obviously introduces a dependency but if you want your tables to behave like real grids with cross-browser support, this will save you pulling your hair out. It also gives you the option of sorting and resizing columns plus tons of other features if you want them.
CSS overflow-x: visible; and overflow-y: hidden; causing scrollbar issue
After some serious searching it seems i've found the answer to my question:
from: http://www.brunildo.org/test/Overflowxy2.html
In Gecko, Safari, Opera, ‘visible’
becomes ‘auto’ also when combined with
‘hidden’ (in other words: ‘visible’
becomes ‘auto’ when combined with
anything else different from
‘visible’). Gecko 1.8, Safari 3, Opera
9.5 are pretty consistent among them.
also the W3C spec says:
The computed values of ‘overflow-x’
and ‘overflow-y’ are the same as their
specified values, except that some
combinations with ‘visible’ are not
possible: if one is specified as
‘visible’ and the other is ‘scroll’ or
‘auto’, then ‘visible’ is set to
‘auto’. The computed value of
‘overflow’ is equal to the computed
value of ‘overflow-x’ if ‘overflow-y’
is the same; otherwise it is the pair
of computed values of ‘overflow-x’ and
‘overflow-y’.
Short Version:
If you are using visible for either overflow-x or overflow-y and something other than visible for the other, the visible value is interpreted as auto.
Logical operators for boolean indexing in Pandas
When you say
(a['x']==1) and (a['y']==10)
You are implicitly asking Python to convert (a['x']==1) and (a['y']==10) to boolean values.
NumPy arrays (of length greater than 1) and Pandas objects such as Series do not have a boolean value -- in other words, they raise
ValueError: The truth value of an array is ambiguous. Use a.empty, a.any() or a.all().
when used as a boolean value. That's because its unclear when it should be True or False. Some users might assume they are True if they have non-zero length, like a Python list. Others might desire for it to be True only if all its elements are True. Others might want it to be True if any of its elements are True.
Because there are so many conflicting expectations, the designers of NumPy and Pandas refuse to guess, and instead raise a ValueError.
Instead, you must be explicit, by calling the empty(), all() or any() method to indicate which behavior you desire.
In this case, however, it looks like you do not want boolean evaluation, you want element-wise logical-and. That is what the & binary operator performs:
(a['x']==1) & (a['y']==10)
returns a boolean array.
By the way, as alexpmil notes,
the parentheses are mandatory since & has a higher operator precedence than ==.
Without the parentheses, a['x']==1 & a['y']==10 would be evaluated as a['x'] == (1 & a['y']) == 10 which would in turn be equivalent to the chained comparison (a['x'] == (1 & a['y'])) and ((1 & a['y']) == 10). That is an expression of the form Series and Series.
The use of and with two Series would again trigger the same ValueError as above. That's why the parentheses are mandatory.
String length in bytes in JavaScript
Took me a while to find a solution for React Native so I'll put it here:
First install the buffer package:
npm install --save buffer
Then user the node method:
const { Buffer } = require('buffer');
const length = Buffer.byteLength(string, 'utf-8');
Cannot declare instance members in a static class in C#
public static class Employee
{
public static string SomeSetting
{
get
{
return ConfigurationManager.AppSettings["SomeSetting"];
}
}
}
Declare the property as static, as well. Also, Don't bother storing a private reference to ConfigurationManager.AppSettings. ConfigurationManager is already a static class.
If you feel that you must store a reference to appsettings, try
public static class Employee
{
private static NameValueCollection _appSettings=ConfigurationManager.AppSettings;
public static NameValueCollection AppSettings { get { return _appSettings; } }
}
It's good form to always give an explicit access specifier (private, public, etc) even though the default is private.
How to handle static content in Spring MVC?
I've just been grappling with this issue in Spring MVC 3.0 and I initially went with the UrlRewriteFilter option. However I was not happy with this solution as it "didn't feel right" (I'm not the only one - see the link above to the Spring Forums where the word "hack" appears a few times).
So I came up with a similar solution to "Unknown (Google)" above but borrowed the idea of having all static content served from /static/ (taken from the Spring Roo version of the Pet Store app). The "default" servlet did not work for me but the Spring Webflow ResourceServlet did (also taken from Spring Roo generated app).
Web.xml:
<servlet>
<servlet-name>mainDispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>2</load-on-startup>
</servlet>
<servlet>
<servlet-name>Resource Servlet</servlet-name>
<servlet-class>org.springframework.js.resource.ResourceServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>mainDispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>Resource Servlet</servlet-name>
<url-pattern>/static/*</url-pattern>
</servlet-mapping>
The only change I made to JSPs was to add the /static/ path to URLs for CSS, JS and images. E.g. "${pageContext.request.contextPath}/static/css/screen.css".
for Maven users the dependency for "org.springframework.js.resource.ResourceServlet" is:
<dependency>
<groupId>org.springframework.webflow</groupId>
<artifactId>org.springframework.js</artifactId>
<version>2.0.8.RELEASE</version>
</dependency>
How do I decode a string with escaped unicode?
Note that the use of unescape() is deprecated and doesn't work with the TypeScript compiler, for example.
Based on radicand's answer and the comments section below, here's an updated solution:
var string = "http\\u00253A\\u00252F\\u00252Fexample.com";
decodeURIComponent(JSON.parse('"' + string.replace(/\"/g, '\\"') + '"'));
http://example.com
Get CPU Usage from Windows Command Prompt
For anyone that stumbles upon this page, none of the solutions here worked for me. I found this is the way to do it (in a batch file):
@for /f "skip=1" %%p in ('wmic cpu get loadpercentage /VALUE') do (
for /F "tokens=2 delims==" %%J in ("%%p") do echo %%J
)
open program minimized via command prompt
I tried this commands in my PC.It is working fine....
To open notepad in minimized mode:
start /min "" "C:\Windows\notepad.exe"
To open MS word in minimized mode:
start /min "" "C:\Program Files\Microsoft Office\Office14\WINWORD.EXE"
What is the meaning of the term "thread-safe"?
Instead of thinking of code or classes as thread safe or not, I think it is more helpful to think of actions as being thread-safe. Two actions are thread safe if they will be behave as specified when run from arbitrary threading contexts. In many cases, classes will support some combinations of actions in thread-safe fashion and others not.
For example, many collections like array-lists and hash sets will guarantee that if they are initially accessed exclusively with one thread, and they are never modified after a reference becomes visible to any other threads, they may be read in arbitrary fashion by any combination of threads without interference.
More interestingly, some hash-set collections such as the original non-generic one in .NET, may offer a guarantee that as long as no item is ever removed, and provided that only one thread ever writes to them, any thread that tries to read the collection will behave as though accessing a collection where updates might be delayed and occur in arbitrary order, but which will otherwise behave normally. If thread #1 adds X and then Y, and thread #2 looks for and sees Y and then X, it would be possible for thread #2 to see that Y exists but X doesn't; whether or not such behavior is "thread-safe" would depend upon whether thread #2 is prepared to deal with that possibility.
As a final note, some classes--especially blocking communications libraries--may have a "close" or "Dispose" method which is thread-safe with respect to all other methods, but no other methods that are thread-safe with respect to each other. If a thread performs a blocking read request and a user of the program clicks "cancel", there would be no way for a close request to be issued by the thread that's attempting to perform the read. The close/dispose request, however, may asynchronously set a flag which will cause the read request to be canceled as soon as possible. Once close is performed on any thread, the object would become useless, and all attempts at future actions would fail immediately, but being able to asynchronously terminate any attempted I/O operations is better than require that the close request be synchronized with the read (since if the read blocks forever, the synchronization request would be likewise blocked).
jQuery Validation plugin: validate check box
There is the easy way
HTML:
<input type="checkbox" name="test[]" />x
<input type="checkbox" name="test[]" />y
<input type="checkbox" name="test[]" />z
<button type="button" id="submit">Submit</button>
JQUERY:
$("#submit").on("click",function(){
if (($("input[name*='test']:checked").length)<=0) {
alert("You must check at least 1 box");
}
return true;
});
For this you not need any plugin.
Enjoy;)
Webpack - webpack-dev-server: command not found
npm install webpack-dev-server -g -- windows OS
Better you use sudo in linux to avoid permission errors
sudo npm install webpack-dev-server -g
You could use sudo npm install webpack-dev-server --save to add it to package.json.
Sometimes you may require to run the below commands.
npm install webpack-cli --save or npm install webpack-cli -g
How do I delete an entity from symfony2
From what I understand, you struggle with what to put into your template.
I'll show an example:
<ul>
{% for guest in guests %}
<li>{{ guest.name }} <a href="{{ path('your_delete_route_name',{'id': guest.id}) }}">[[DELETE]]</a></li>
{% endfor %}
</ul>
Now what happens is it iterates over every object within guests (you'll have to rename this if your object collection is named otherwise!), shows the name and places the correct link. The route name might be different.
How to tell which row number is clicked in a table?
A simple and jQuery free solution:
document.querySelector('#elitable').onclick = function(ev) {
// ev.target <== td element
// ev.target.parentElement <== tr
var index = ev.target.parentElement.rowIndex;
}
Bonus: It works even if rows are added/removed dynamically
Bootstrap Responsive Text Size
Well, my solution is sort of hack, but it works and I am using it.
1vw = 1% of viewport width
1vh = 1% of viewport height
1vmin = 1vw or 1vh, whichever is smaller
1vmax = 1vw or 1vh, whichever is larger
h1 {
font-size: 5.9vw;
}
h2 {
font-size: 3.0vh;
}
p {
font-size: 2vmin;
}
How to check if a string contains only numbers?
You may just remove all spaces and leverage LINQ All:
Determines whether all elements of a sequence satisfy a condition.
Use it as shown below:
Dim number As String = "077 234 211"
If number.Replace(" ", "").All(AddressOf Char.IsDigit) Then
Console.WriteLine("The string is all numeric (spaces ignored)!")
Else
Console.WriteLine("The string contains a char that is not numeric and space!")
End If
To only check if a string consists of only digits use:
If number.All(AddressOf Char.IsDigit) Then
What does the ^ (XOR) operator do?
^ is the Python bitwise XOR operator. It is how you spell XOR in python:
>>> 0 ^ 0
0
>>> 0 ^ 1
1
>>> 1 ^ 0
1
>>> 1 ^ 1
0
XOR stands for exclusive OR. It is used in cryptography because it let's you 'flip' the bits using a mask in a reversable operation:
>>> 10 ^ 5
15
>>> 15 ^ 5
10
where 5 is the mask; (input XOR mask) XOR mask gives you the input again.
Automapper missing type map configuration or unsupported mapping - Error
I had same issue in .Net Core. Because my base dto class(i give it as a type in startup for automapper assembly) was in different project. Automapper tried to search for profiles in base class project. But my dto's were in different project. I moved my base class. And problem solved. This may help for some persons.
Can a CSS class inherit one or more other classes?
While direct inheritance isn't possible.
It is possible to use a class (or id) for a parent tag and then use CSS combinators to alter child tag behaviour from it's heirarchy.
_x000D_
_x000D_
p.test{background-color:rgba(55,55,55,0.1);}_x000D_
p.test > span{background-color:rgba(55,55,55,0.1);}_x000D_
p.test > span > span{background-color:rgba(55,55,55,0.1);}_x000D_
p.test > span > span > span{background-color:rgba(55,55,55,0.1);}_x000D_
p.test > span > span > span > span{background-color:rgba(55,55,55,0.1);}_x000D_
p.test > span > span > span > span > span{background-color:rgba(55,55,55,0.1);}_x000D_
p.test > span > span > span > span > span > span{background-color:rgba(55,55,55,0.1);}_x000D_
p.test > span > span > span > span > span > span > span{background-color:rgba(55,55,55,0.1);}_x000D_
p.test > span > span > span > span > span > span > span > span{background-color:rgba(55,55,55,0.1);}
_x000D_
<p class="test"><span>One <span>possible <span>solution <span>is <span>using <span>multiple <span>nested <span>tags</span></span></span></span></span></span></span></span></p>
_x000D_
_x000D_
_x000D_
I wouldn't suggest using so many spans like the example, however it's just a proof of concept. There are still many bugs that can arise when trying to apply CSS in this manner. (For example altering text-decoration types).
How to add images to README.md on GitHub?
There are 2 simple way you can do this ,
1) use HTML img tag ,
2) 
the path would you can copy from the URL in the browser while you have opened that image.
there might be an issue occur of spacing so make sure if there is any space b/w two words of path or in image name add-> %20. just like browser do.
Both of them will work , if you want to understand more you can check my github -> https://github.com/adityarawat29
Editing the date formatting of x-axis tick labels in matplotlib
From the package matplotlib.dates as shown in this example the date format can be applied to the axis label and ticks for plot.
Below I have given an example for labeling axis ticks for multiplots
import matplotlib.pyplot as plt
import matplotlib.dates as mdates
import pandas as pd
df = pd.read_csv('US_temp.csv')
plt.plot(df['Date'],df_f['MINT'],label='Min Temp.')
plt.plot(df['Date'],df_f['MAXT'],label='Max Temp.')
plt.legend()
####### Use the below functions #######
dtFmt = mdates.DateFormatter('%b') # define the formatting
plt.gca().xaxis.set_major_formatter(dtFmt) # apply the format to the desired axis
plt.show()
As simple as that
php create object without class
you can always use new stdClass(). Example code:
$object = new stdClass();
$object->property = 'Here we go';
var_dump($object);
/*
outputs:
object(stdClass)#2 (1) {
["property"]=>
string(10) "Here we go"
}
*/
Also as of PHP 5.4 you can get same output with:
$object = (object) ['property' => 'Here we go'];
Can I get JSON to load into an OrderedDict?
Simple version for Python 2.7+
my_ordered_dict = json.loads(json_str, object_pairs_hook=collections.OrderedDict)
Or for Python 2.4 to 2.6
import simplejson as json
import ordereddict
my_ordered_dict = json.loads(json_str, object_pairs_hook=ordereddict.OrderedDict)
Explanation on Integer.MAX_VALUE and Integer.MIN_VALUE to find min and max value in an array
Instead of initializing the variables with arbitrary values (for example int smallest = 9999, largest = 0) it is safer to initialize the variables with the largest and smallest values representable by that number type (that is int smallest = Integer.MAX_VALUE, largest = Integer.MIN_VALUE).
Since your integer array cannot contain a value larger than Integer.MAX_VALUE and smaller than Integer.MIN_VALUE your code works across all edge cases.
Getter and Setter?
Generally speaking, the first way is more popular overall because those with prior programming knowledge can easily transition to PHP and get work done in an object-oriented fashion. The first way is more universal. My advice would be to stick with what is tried and true across many languages. Then, when and if you use another language, you'll be ready to get something accomplished (instead of spending time reinventing the wheel).
Get a list of checked checkboxes in a div using jQuery
If you need to get quantity of selected checkboxes:
var selected = []; // initialize array
$('div#checkboxes input[type=checkbox]').each(function() {
if ($(this).is(":checked")) {
selected.push($(this));
}
});
var selectedQuantity = selected.length;
PostgreSQL: Resetting password of PostgreSQL on Ubuntu
Assuming you're the administrator of the machine, Ubuntu has granted you the right to sudo to run any command as any user.
Also assuming you did not restrict the rights in the pg_hba.conf file (in the /etc/postgresql/9.1/main directory), it should contain this line as the first rule:
# Database administrative login by Unix domain socket
local all postgres peer
(About the file location: 9.1 is the major postgres version and main the name of your "cluster". It will differ if using a newer version of postgres or non-default names. Use the pg_lsclusters command to obtain this information for your version/system).
Anyway, if the pg_hba.conf file does not have that line, edit the file, add it, and reload the service with sudo service postgresql reload.
Then you should be able to log in with psql as the postgres superuser with this shell command:
sudo -u postgres psql
Once inside psql, issue the SQL command:
ALTER USER postgres PASSWORD 'newpassword';
In this command, postgres is the name of a superuser. If the user whose password is forgotten was ritesh, the command would be:
ALTER USER ritesh PASSWORD 'newpassword';
References: PostgreSQL 9.1.13 Documentation, Chapter 19. Client Authentication
Keep in mind that you need to type postgres with a single S at the end
If leaving the password in clear text in the history of commands or the server log is a problem, psql provides an interactive meta-command to avoid that, as an alternative to ALTER USER ... PASSWORD:
\password username
It asks for the password with a double blind input, then hashes it according to the password_encryption setting and issue the ALTER USER command to the server with the hashed version of the password, instead of the clear text version.
Load HTML file into WebView
The Accepted Answer is not working for me, This is what works for me
WebSettings webSetting = webView.getSettings();
webSetting.setBuiltInZoomControls(true);
webView1.setWebViewClient(new WebViewClient());
webView.loadUrl("file:///android_asset/index.html");
How to use <DllImport> in VB.NET?
I know this has already been answered, but here is an example for the people who are trying to use SQL Server Types in a vb project:
Imports System
Imports System.IO
Imports System.Runtime.InteropServices
Namespace SqlServerTypes
Public Class Utilities
<DllImport("kernel32.dll", CharSet:=CharSet.Auto, SetLastError:=True)>
Public Shared Function LoadLibrary(ByVal libname As String) As IntPtr
End Function
Public Shared Sub LoadNativeAssemblies(ByVal rootApplicationPath As String)
Dim nativeBinaryPath = If(IntPtr.Size > 4, Path.Combine(rootApplicationPath, "SqlServerTypes\x64\"), Path.Combine(rootApplicationPath, "SqlServerTypes\x86\"))
LoadNativeAssembly(nativeBinaryPath, "msvcr120.dll")
LoadNativeAssembly(nativeBinaryPath, "SqlServerSpatial140.dll")
End Sub
Private Shared Sub LoadNativeAssembly(ByVal nativeBinaryPath As String, ByVal assemblyName As String)
Dim path = System.IO.Path.Combine(nativeBinaryPath, assemblyName)
Dim ptr = LoadLibrary(path)
If ptr = IntPtr.Zero Then
Throw New Exception(String.Format("Error loading {0} (ErrorCode: {1})", assemblyName, Marshal.GetLastWin32Error()))
End If
End Sub
End Class
End Namespace
Why aren't Xcode breakpoints functioning?
I have a lot of problems with breakpoints in Xcode (2.4.1). I use a project that just contains other projects (like a Solution in Visual Studio). I find sometimes that breakpoints don't work at all unless there is at least one breakpoint set in the starting project (i.e. the one containing the entry point for my code). If the only breakpoints are in "lower level" projects, they just get ignored.
It also seems as if Xcode only handles breakpoint operations correctly if you act on the breakpoint when you're in the project that contains the source line the breakpoint's on.
If I try deleting or disabling breakpoints via another project, the action sometimes doesn't take effect, even though the debugger indicates that it has. So I will find myself breaking on disabled breakpoints, or on a (now invisible) breakpoint that I removed earlier.
Figuring out whether a number is a Double in Java
Reflection is slower, but works for a situation when you want to know whether that is of type Dog or a Cat and not an instance of Animal. So you'd do something like:
if(null != items.elementAt(1) && items.elementAt(1).getClass().toString().equals("Cat"))
{
//do whatever with cat.. not any other instance of animal.. eg. hideClaws();
}
Not saying the answer above does not work, except the null checking part is necessary.
Another way to answer that is use generics and you are guaranteed to have Double as any element of items.
List<Double> items = new ArrayList<Double>();
combining two data frames of different lengths
i had similar problem, i matched the entries in a particular column of two data sets and cbind only if it matched.
For two data sets, data1 & data2, i am adding a column in data1 from data2 after comparing first column of both.
for(i in 1:nrow(data1){
for( j in 1:nrow(data2){
if (data1[i,1]==data2[j,1]) data1[i,3]<- data2[j,2]
}
}
How to create a simple http proxy in node.js?
Super simple and readable, here's how you create a local proxy server to a local HTTP server with just Node.js (tested on v8.1.0). I've found it particular useful for integration testing so here's my share:
/**
* Once this is running open your browser and hit http://localhost
* You'll see that the request hits the proxy and you get the HTML back
*/
'use strict';
const net = require('net');
const http = require('http');
const PROXY_PORT = 80;
const HTTP_SERVER_PORT = 8080;
let proxy = net.createServer(socket => {
socket.on('data', message => {
console.log('---PROXY- got message', message.toString());
let serviceSocket = new net.Socket();
serviceSocket.connect(HTTP_SERVER_PORT, 'localhost', () => {
console.log('---PROXY- Sending message to server');
serviceSocket.write(message);
});
serviceSocket.on('data', data => {
console.log('---PROXY- Receiving message from server', data.toString();
socket.write(data);
});
});
});
let httpServer = http.createServer((req, res) => {
switch (req.url) {
case '/':
res.writeHead(200, {'Content-Type': 'text/html'});
res.end('<html><body><p>Ciao!</p></body></html>');
break;
default:
res.writeHead(404, {'Content-Type': 'text/plain'});
res.end('404 Not Found');
}
});
proxy.listen(PROXY_PORT);
httpServer.listen(HTTP_SERVER_PORT);
https://gist.github.com/fracasula/d15ae925835c636a5672311ef584b999
How big can a MySQL database get before performance starts to degrade
I once was called upon to look at a mysql that had "stopped working". I discovered that the DB files were residing on a Network Appliance filer mounted with NFS2 and with a maximum file size of 2GB. And sure enough, the table that had stopped accepting transactions was exactly 2GB on disk. But with regards to the performance curve I'm told that it was working like a champ right up until it didn't work at all! This experience always serves for me as a nice reminder that there're always dimensions above and below the one you naturally suspect.
TypeError: object of type 'int' has no len() error assistance needed
Abstract:
The reason why you are getting this error message is because you are trying to call a method on an int type of a variable. This would work if would have called len() function on a list type of a variable. Let's examin the two cases:
Fail:
num = 10
print(len(num))
The above will produce an error similar to yours due to calling len() function on an int type of a variable;
Success:
data = [0, 4, 8, 9, 12]
print(len(data))
The above will work since you are calling a function on a list type of a variable;
html table cell width for different rows
One solution would be to divide your table into 20 columns of 5% width each, then use colspan on each real column to get the desired width, like this:
_x000D_
_x000D_
<html>_x000D_
<body bgcolor="#14B3D9">_x000D_
<table width="100%" border="1" bgcolor="#ffffff">_x000D_
<colgroup>_x000D_
<col width="5%"><col width="5%">_x000D_
<col width="5%"><col width="5%">_x000D_
<col width="5%"><col width="5%">_x000D_
<col width="5%"><col width="5%">_x000D_
<col width="5%"><col width="5%">_x000D_
<col width="5%"><col width="5%">_x000D_
<col width="5%"><col width="5%">_x000D_
<col width="5%"><col width="5%">_x000D_
<col width="5%"><col width="5%">_x000D_
<col width="5%"><col width="5%">_x000D_
</colgroup>_x000D_
<tr>_x000D_
<td colspan=5>25</td>_x000D_
<td colspan=10>50</td>_x000D_
<td colspan=5>25</td>_x000D_
</tr>_x000D_
<tr>_x000D_
<td colspan=10>50</td>_x000D_
<td colspan=6>30</td>_x000D_
<td colspan=4>20</td>_x000D_
</tr>_x000D_
</table>_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_
JSFIDDLE
Plot data in descending order as appears in data frame
You want reorder(). Here is an example with dummy data
set.seed(42)
df <- data.frame(Category = sample(LETTERS), Count = rpois(26, 6))
require("ggplot2")
p1 <- ggplot(df, aes(x = Category, y = Count)) +
geom_bar(stat = "identity")
p2 <- ggplot(df, aes(x = reorder(Category, -Count), y = Count)) +
geom_bar(stat = "identity")
require("gridExtra")
grid.arrange(arrangeGrob(p1, p2))
Giving:
Use reorder(Category, Count) to have Category ordered from low-high.
How do I get the XML root node with C#?
Root node is the DocumentElement property of XmlDocument
XmlElement root = xmlDoc.DocumentElement
If you only have the node, you can get the root node by
XmlElement root = xmlNode.OwnerDocument.DocumentElement
Structs data type in php?
A public class is one option, if you want something more encapsulated you can use an abstract/anonymous class combination. My favorite part is that autocomplete still works (for PhpStorm) for this but I don't have a public class sitting around.
<?php
final class MyParentClass
{
/**
* @return MyStruct[]
*/
public function getData(): array
{
return array(
$this->createMyObject("One", 1.0, new DateTime("now")),
$this->createMyObject("Two", 2.0, new DateTime("tommorow"))
);
}
private function createMyObject(string $description, float $magnitude, DateTime $timeStamp): MyStruct
{
return new class(func_get_args()) extends MyStruct {
protected function __construct(array $args)
{
$this->description = $args[0];
$this->magnitude = $args[1];
$this->timeStamp = $args[2];
}
};
}
}
abstract class MyStruct
{
public string $description;
public float $magnitude;
public DateTime $timeStamp;
}
Lambda function in list comprehensions
This question touches a very stinking part of the "famous" and "obvious" Python syntax - what takes precedence, the lambda, or the for of list comprehension.
I don't think the purpose of the OP was to generate a list of squares from 0 to 9. If that was the case, we could give even more solutions:
squares = []
for x in range(10): squares.append(x*x)
- this is the good ol' way of imperative syntax.
But it's not the point. The point is W(hy)TF is this ambiguous expression so counter-intuitive? And I have an idiotic case for you at the end, so don't dismiss my answer too early (I had it on a job interview).
So, the OP's comprehension returned a list of lambdas:
[(lambda x: x*x) for x in range(10)]
This is of course just 10 different copies of the squaring function, see:
>>> [lambda x: x*x for _ in range(3)]
[<function <lambda> at 0x00000000023AD438>, <function <lambda> at 0x00000000023AD4A8>, <function <lambda> at 0x00000000023AD3C8>]
Note the memory addresses of the lambdas - they are all different!
You could of course have a more "optimal" (haha) version of this expression:
>>> [lambda x: x*x] * 3
[<function <lambda> at 0x00000000023AD2E8>, <function <lambda> at 0x00000000023AD2E8>, <function <lambda> at 0x00000000023AD2E8>]
See? 3 time the same lambda.
Please note, that I used _ as the for variable. It has nothing to do with the x in the lambda (it is overshadowed lexically!). Get it?
I'm leaving out the discussion, why the syntax precedence is not so, that it all meant:
[lambda x: (x*x for x in range(10))]
which could be: [[0, 1, 4, ..., 81]], or [(0, 1, 4, ..., 81)], or which I find most logical, this would be a list of 1 element - a generator returning the values. It is just not the case, the language doesn't work this way.
BUT What, If...
What if you DON'T overshadow the for variable, AND use it in your lambdas???
Well, then crap happens. Look at this:
[lambda x: x * i for i in range(4)]
this means of course:
[(lambda x: x * i) for i in range(4)]
BUT it DOESN'T mean:
[(lambda x: x * 0), (lambda x: x * 1), ... (lambda x: x * 3)]
This is just crazy!
The lambdas in the list comprehension are a closure over the scope of this comprehension. A lexical closure, so they refer to the i via reference, and not its value when they were evaluated!
So, this expression:
[(lambda x: x * i) for i in range(4)]
IS roughly EQUIVALENT to:
[(lambda x: x * 3), (lambda x: x * 3), ... (lambda x: x * 3)]
I'm sure we could see more here using a python decompiler (by which I mean e.g. the dis module), but for Python-VM-agnostic discussion this is enough.
So much for the job interview question.
Now, how to make a list of multiplier lambdas, which really multiply by consecutive integers? Well, similarly to the accepted answer, we need to break the direct tie to i by wrapping it in another lambda, which is getting called inside the list comprehension expression:
Before:
>>> a = [(lambda x: x * i) for i in (1, 2)]
>>> a[1](1)
2
>>> a[0](1)
2
After:
>>> a = [(lambda y: (lambda x: y * x))(i) for i in (1, 2)]
>>> a[1](1)
2
>>> a[0](1)
1
(I had the outer lambda variable also = i, but I decided this is the clearer solution - I introduced y so that we can all see which witch is which).
Edit 2019-08-30:
Following a suggestion by @josoler, which is also present in an answer by @sheridp - the value of the list comprehension "loop variable" can be "embedded" inside an object - the key is for it to be accessed at the right time. The section "After" above does it by wrapping it in another lambda and calling it immediately with the current value of i. Another way (a little bit easier to read - it produces no 'WAT' effect) is to store the value of i inside a partial object, and have the "inner" (original) lambda take it as an argument (passed supplied by the partial object at the time of the call), i.e.:
After 2:
>>> from functools import partial
>>> a = [partial(lambda y, x: y * x, i) for i in (1, 2)]
>>> a[0](2), a[1](2)
(2, 4)
Great, but there is still a little twist for you! Let's say we wan't to make it easier on the code reader, and pass the factor by name (as a keyword argument to partial). Let's do some renaming:
After 2.5:
>>> a = [partial(lambda coef, x: coef * x, coef=i) for i in (1, 2)]
>>> a[0](1)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: <lambda>() got multiple values for argument 'coef'
WAT?
>>> a[0]()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: <lambda>() missing 1 required positional argument: 'x'
Wait... We're changing the number of arguments by 1, and going from "too many" to "too few"?
Well, it's not a real WAT, when we pass coef to partial in this way, it becomes a keyword argument, so it must come after the positional x argument, like so:
After 3:
>>> a = [partial(lambda x, coef: coef * x, coef=i) for i in (1, 2)]
>>> a[0](2), a[1](2)
(2, 4)
I would prefer the last version over the nested lambda, but to each their own...
Edit 2020-08-18:
Thanks to commenter dasWesen, I found out that this stuff is covered in the Python documentation: https://docs.python.org/3.4/faq/programming.html#why-do-lambdas-defined-in-a-loop-with-different-values-all-return-the-same-result - it deals with loops instead of list comprehensions, but the idea is the same - global or nonlocal variable access in the lambda function. There's even a solution - using default argument values (like for any function):
>>> a = [lambda x, coef=i: coef * x for i in (1, 2)]
>>> a[0](2), a[1](2)
(2, 4)
This way the coef value is bound to the value of i at the time of function definition (see James Powell's talk "Top To Down, Left To Right", which also explains why mutable default values are shunned).
Android Studio: Plugin with id 'android-library' not found
Add the below to the build.gradle project module:
// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
repositories {
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:2.2.3'
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
jcenter()
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
How to extract the n-th elements from a list of tuples?
Found this as I was searching for which way is fastest to pull the second element of a 2-tuple list. Not what I wanted but ran same test as shown with a 3rd method plus test the zip method
setup = 'elements = [(1,1) for _ in range(100000)];from operator import itemgetter'
method1 = '[x[1] for x in elements]'
method2 = 'map(itemgetter(1), elements)'
method3 = 'dict(elements).values()'
method4 = 'zip(*elements)[1]'
import timeit
t = timeit.Timer(method1, setup)
print('Method 1: ' + str(t.timeit(100)))
t = timeit.Timer(method2, setup)
print('Method 2: ' + str(t.timeit(100)))
t = timeit.Timer(method3, setup)
print('Method 3: ' + str(t.timeit(100)))
t = timeit.Timer(method4, setup)
print('Method 4: ' + str(t.timeit(100)))
Method 1: 0.618785858154
Method 2: 0.711684942245
Method 3: 0.298138141632
Method 4: 1.32586884499
So over twice as fast if you have a 2 tuple pair to just convert to a dict and take the values.
open resource with relative path in Java
In Order to obtain real path to the file you can try this:
URL fileUrl = Resourceloader.class.getResource("resources/repository/SSL-Key/cert.jks");
String pathToClass = fileUrl.getPath;
Resourceloader is classname here.
"resources/repository/SSL-Key/cert.jks" is relative path to the file. If you had your guiclass in ./package1/java with rest of folder structure remaining, you would take "../resources/repository/SSL-Key/cert.jks" as relative path because of rules defining relative path.
This way you can read your file with BufferedReader. DO NOT USE THE STRING to identify the path to the file, because if you have spaces or some characters from not english alphabet in your path, you will get problems and the file will not be found.
BufferedReader bufferedReader = new BufferedReader(
new InputStreamReader(fileUrl.openStream()));
Scroll RecyclerView to show selected item on top
If you are using the LinearLayoutManager or Staggered GridLayoutManager, they each have a scrollToPositionWithOffset method that takes both the position and also the offset of the start of the item from the start of the RecyclerView, which seems like it would accomplish what you need (setting the offset to 0 should align with the top).
For instance:
//Scroll item 2 to 20 pixels from the top
linearLayoutManager.scrollToPositionWithOffset(2, 20);
How to select and change value of table cell with jQuery?
I wanted to change the column value in a specific row. Thanks to above answers
and after some serching able to come up with below,
var dataTable = $("#yourtableid");
var rowNumber = 0;
var columnNumber= 2;
dataTable[0].rows[rowNumber].cells[columnNumber].innerHTML = 'New Content';
How to determine if a number is positive or negative?
This solution uses no conditional operators, but relies on catching two excpetions.
A division error equates to the number originally being "negative". Alternatively, the number will eventually fall off the planet and throw a StackOverFlow exception if it is positive.
public static boolean isPositive( f)
{
int x;
try {
x = 1/((int)f + 1);
return isPositive(x+1);
} catch (StackOverFlow Error e) {
return true;
} catch (Zero Division Error e) {
return false;
}
}
Populate one dropdown based on selection in another
_x000D_
_x000D_
function configureDropDownLists(ddl1, ddl2) {_x000D_
var colours = ['Black', 'White', 'Blue'];_x000D_
var shapes = ['Square', 'Circle', 'Triangle'];_x000D_
var names = ['John', 'David', 'Sarah'];_x000D_
_x000D_
switch (ddl1.value) {_x000D_
case 'Colours':_x000D_
ddl2.options.length = 0;_x000D_
for (i = 0; i < colours.length; i++) {_x000D_
createOption(ddl2, colours[i], colours[i]);_x000D_
}_x000D_
break;_x000D_
case 'Shapes':_x000D_
ddl2.options.length = 0;_x000D_
for (i = 0; i < shapes.length; i++) {_x000D_
createOption(ddl2, shapes[i], shapes[i]);_x000D_
}_x000D_
break;_x000D_
case 'Names':_x000D_
ddl2.options.length = 0;_x000D_
for (i = 0; i < names.length; i++) {_x000D_
createOption(ddl2, names[i], names[i]);_x000D_
}_x000D_
break;_x000D_
default:_x000D_
ddl2.options.length = 0;_x000D_
break;_x000D_
}_x000D_
_x000D_
}_x000D_
_x000D_
function createOption(ddl, text, value) {_x000D_
var opt = document.createElement('option');_x000D_
opt.value = value;_x000D_
opt.text = text;_x000D_
ddl.options.add(opt);_x000D_
}
_x000D_
<select id="ddl" onchange="configureDropDownLists(this,document.getElementById('ddl2'))">_x000D_
<option value=""></option>_x000D_
<option value="Colours">Colours</option>_x000D_
<option value="Shapes">Shapes</option>_x000D_
<option value="Names">Names</option>_x000D_
</select>_x000D_
_x000D_
<select id="ddl2">_x000D_
</select>
_x000D_
_x000D_
_x000D_
How to go back to previous page if back button is pressed in WebView?
The first answer by FoamyGuy is correct but I have some additions; low reputations cannot allow me to do comments. If for some reasons your page fails to load, ensure that you set a flag to take note of the failure and then check it on the onBackPressed override. Otherwise your canGoBack() will be forever executed without heading to the actual back activity if it was there:
//flag with class wide access
public boolean ploadFailFlag = false;
//your error handling override
@Override
public void onReceivedError(WebView view, WebResourceRequest req, WebResourceError rerr) {
onReceivedError(view, rerr.getErrorCode(), rerr.getDescription().toString(), req.getUrl().toString());
ploadFailFlag = true; //note this change
.....
.....
}
//finally to the answer to this question:
@Override
public void onBackPressed() {
if(checkinWebView.canGoBack()){
//if page load fails, go back for web view will not go back - no page to go to - yet overriding the super
if(ploadFailFlag){
super.onBackPressed();
}else {
checkinWebView.goBack();
}
}else {
Toast.makeText(getBaseContext(), "super:", Toast.LENGTH_LONG).show();
super.onBackPressed();
}
}
How do I parse a string with a decimal point to a double?
Double.Parse("3,5".Replace(',', '.'), CultureInfo.InvariantCulture)
Replace the comma with a point before parsing. Useful in countries with a comma as decimal separator. Think about limiting user input (if necessary) to one comma or point.
convert string to specific datetime format?
No need to apply anything. Just add this code at the end of variable to which date is assigned. For example
@todaydate = "2011-05-19 10:30:14"
@todaytime.to_time.strftime('%a %b %d %H:%M:%S %Z %Y')
You will get proper format as you like. You can check this at Rails Console
Loading development environment (Rails 3.0.4)
ruby-1.9.2-p136 :001 > todaytime = "2011-05-19 10:30:14"
=> "2011-05-19 10:30:14"
ruby-1.9.2-p136 :002 > todaytime
=> "2011-05-19 10:30:14"
ruby-1.9.2-p136 :003 > todaytime.to_time
=> 2011-05-19 10:30:14 UTC
ruby-1.9.2-p136 :008 > todaytime.to_time.strftime('%a %b %d %H:%M:%S %Z %Y')
=> "Thu May 19 10:30:14 UTC 2011"
Try 'date_format' gem to show date in different format.
How should I escape commas and speech marks in CSV files so they work in Excel?
Single quotes work fine too, even without escaping the double quotes, at least in Excel 2016:
'text with spaces, and a comma','more text with spaces','spaces and "quoted text" and more spaces','nospaces','NOSPACES1234'
Excel will put that in 5 columns (if you choose the single quote as "Text qualifier" in the "Text to columns" wizard)
Visual Studio Post Build Event - Copy to Relative Directory Location
Would it not make sense to use msbuild directly? If you are doing this with every build, then you can add a msbuild task at the end? If you would just like to see if you can’t find another macro value that is not showed on the Visual Studio IDE, you could switch on the msbuild options to diagnostic and that will show you all of the variables that you could use, as well as their current value.
To switch this on in visual studio, go to Tools/Options then scroll down the tree view to the section called Projects and Solutions, expand that and click on Build and Run, at the right their is a drop down that specify the build output verbosity, setting that to diagnostic, will show you what other macro values you could use.
Because I don’t quite know to what level you would like to go, and how complex you want your build to be, this might give you some idea. I have recently been doing build scripts, that even execute SQL code as part of the build. If you would like some more help or even some sample build scripts, let me know, but if it is just a small process you want to run at the end of the build, the perhaps going the full msbuild script is a bit of over kill.
Hope it helps
Rihan
How do you handle multiple submit buttons in ASP.NET MVC Framework?
Give your submit buttons a name, and then inspect the submitted value in your controller method:
<% Html.BeginForm("MyAction", "MyController", FormMethod.Post); %>
<input type="submit" name="submitButton" value="Send" />
<input type="submit" name="submitButton" value="Cancel" />
<% Html.EndForm(); %>
posting to
public class MyController : Controller {
public ActionResult MyAction(string submitButton) {
switch(submitButton) {
case "Send":
// delegate sending to another controller action
return(Send());
case "Cancel":
// call another action to perform the cancellation
return(Cancel());
default:
// If they've submitted the form without a submitButton,
// just return the view again.
return(View());
}
}
private ActionResult Cancel() {
// process the cancellation request here.
return(View("Cancelled"));
}
private ActionResult Send() {
// perform the actual send operation here.
return(View("SendConfirmed"));
}
}
EDIT:
To extend this approach to work with localized sites, isolate your messages somewhere else (e.g. compiling a resource file to a strongly-typed resource class)
Then modify the code so it works like:
<% Html.BeginForm("MyAction", "MyController", FormMethod.Post); %>
<input type="submit" name="submitButton" value="<%= Html.Encode(Resources.Messages.Send)%>" />
<input type="submit" name="submitButton" value="<%=Html.Encode(Resources.Messages.Cancel)%>" />
<% Html.EndForm(); %>
and your controller should look like this:
// Note that the localized resources aren't constants, so
// we can't use a switch statement.
if (submitButton == Resources.Messages.Send) {
// delegate sending to another controller action
return(Send());
} else if (submitButton == Resources.Messages.Cancel) {
// call another action to perform the cancellation
return(Cancel());
}
Want custom title / image / description in facebook share link from a flash app
I had this same problem a week ago.
First of all I noticed your URL has an ampersand preceding the parameter string, but it probably needs to have a question mark instead to begin the parameter string, followed by an ampersand between each additional parameter.
Now, you do need to escape your URL but also double-escape the URL parameters (title or other content you need to provide content in the Share) you are passing to the URL, as follows:
var myParams = 't=' + escape('Some title here.') + '&id=' + escape('some content ID or any other value I want to load');
var fooBar = 'http://www.facebook.com/share.php?u=' + escape('http://foobar.com/superDuperSharingPage.php?' + myParams);
Now, you need to create the above-linked superDuperSharingPage.php, which should provide the dynamic title, description, and image content you desire. Something like this should suffice:
<?php
// get our URL query parameters
$title = $_GET['t'];
$id = $_GET['id'];
// maybe we want to load some content with the id I'll pretend we loaded a
// description from some database in the sky which is magically arranged thusly:
$desciption = $databaseInTheSky[$id]['description'];
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title><?php echo $title;?></title>
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
<meta name="title" content="<?php echo $title;?>" />
<meta name="description" content="<?php echo $desciption;?>" />
<!-- the following line redirects to wherever we want the USER to land -->
<!-- Facebook won't follow it. you may or may not actually want || need this. -->
<meta http-equiv="refresh" content="1;URL=http://foobar.com" />
</head>
<body>
<p><?php echo $desciption;?></p>
<p><img src="image_a_<?php echo $id;?>.jpg" alt="Alt tags are always a good idea." /></p>
<p><img src="image_b_<?php echo $id;?>.jpg" alt="Make the web more accessible to the blind!" /></p>
</body>
</html>
Let me know if this works for you, it's essentially what did for me :)
Mocking Extension Methods with Moq
You can easily mock an extension method with JustMock. The API is the same as mocking normal method. Consider the following
public static string Echo(this Foo foo, string strValue)
{
return strValue;
}
To arrange and verify this method use the following:
string expected = "World";
var foo = new Foo();
Mock.Arrange(() => foo.Echo(Arg.IsAny<string>())).Returns(expected);
string result = foo.Echo("Hello");
Assert.AreEqual(expected, result);
Here is also a link to the documentation: Extension Methods Mocking
Disclaimer. I am one of the developers responsible for JustMock.
Time complexity of accessing a Python dict
See Time Complexity. The python dict is a hashmap, its worst case is therefore O(n) if the hash function is bad and results in a lot of collisions. However that is a very rare case where every item added has the same hash and so is added to the same chain which for a major Python implementation would be extremely unlikely. The average time complexity is of course O(1).
The best method would be to check and take a look at the hashs of the objects you are using. The CPython Dict uses int PyObject_Hash (PyObject *o) which is the equivalent of hash(o).
After a quick check, I have not yet managed to find two tuples that hash to the same value, which would indicate that the lookup is O(1)
l = []
for x in range(0, 50):
for y in range(0, 50):
if hash((x,y)) in l:
print "Fail: ", (x,y)
l.append(hash((x,y)))
print "Test Finished"
CodePad (Available for 24 hours)
How do I use an image as a submit button?
Use an image type input:
<input type="image" src="/Button1.jpg" border="0" alt="Submit" />
The full HTML:
_x000D_
_x000D_
<form id='formName' name='formName' onsubmit='redirect();return false;'>_x000D_
<div class="style7">_x000D_
<input type='text' id='userInput' name='userInput' value=''>_x000D_
<input type="image" name="submit" src="https://jekyllcodex.org/uploads/grumpycat.jpg" border="0" alt="Submit" style="width: 50px;" />_x000D_
</div>_x000D_
</form>
_x000D_
_x000D_
_x000D_
How do I use sudo to redirect output to a location I don't have permission to write to?
Someone here has just suggested sudoing tee:
sudo ls -hal /root/ | sudo tee /root/test.out > /dev/null
This could also be used to redirect any command, to a directory that you do not have access to. It works because the tee program is effectively an "echo to a file" program, and the redirect to /dev/null is to stop it also outputting to the screen to keep it the same as the original contrived example above.
Excel Define a range based on a cell value
This should be close to what you are looking for your first example:
=SUM(INDIRECT("A1:A"&B1,TRUE))
This should be close to what you are looking for your final example:
=SUM(INDIRECT("A"&1+B1&":A"&B1,TRUE))
Put Excel-VBA code in module or sheet?
In my experience it's best to put as much code as you can into well-named modules, and only put as much code as you need to into the actual worksheet objects.
Example: Any code that uses worksheet events like Worksheet_SelectionChange or Worksheet_Calculate.
reducing number of plot ticks
If somebody still gets this page in search results:
fig, ax = plt.subplots()
plt.plot(...)
every_nth = 4
for n, label in enumerate(ax.xaxis.get_ticklabels()):
if n % every_nth != 0:
label.set_visible(False)
How to compile C program on command line using MinGW?
I've had this problem and couldn't find why it kept happening. The reason is simple: Once you have set up the environment paths, you have to close the CMD window, and open it again for it be aware of new environment paths.
How does internationalization work in JavaScript?
Localization support in legacy browsers is poor. Originally, this was due to phrases in the ECMAScript language spec that look like this:
Number.prototype.toLocaleString()
Produces a string value that represents the value of the Number formatted according to the
conventions of the host environment’s current locale. This function is implementation-dependent, and
it is permissible, but not encouraged, for it to return the same thing as toString.
Every localization method defined in the spec is defined as "implementation-dependent", which results in a lot of inconsistencies. In this instance, Chrome Opera and Safari would return the same thing as .toString(). Firefox and IE will return locale formatted strings, and IE even includes a thousand separator (perfect for currency strings). Chrome was recently updated to return a thousands-separated string, though with no fixed decimal.
For modern environments, the ECMAScript Internationalization API spec, a new standard that complements the ECMAScript Language spec, provides much better support for string comparison, number formatting, and the date and time formatting; it also fixes the corresponding functions in the Language Spec. An introduction can be found here. Implementations are available in:
- Chrome 24
- Firefox 29
- Internet Explorer 11
- Opera 15
There is also a compatibility implementation, Intl.js, which will provide the API in environments where it doesn't already exist.
Determining the user's preferred language remains a problem since there's no specification for obtaining the current language. Each browser implements a method to obtain a language string, but this could be based on the user's operating system language or just the language of the browser:
// navigator.userLanguage for IE, navigator.language for others
var lang = navigator.language || navigator.userLanguage;
A good workaround for this is to dump the Accept-Language header from the server to the client. If formatted as a JavaScript, it can be passed to the Internationalization API constructors, which will automatically pick the best (or first-supported) locale.
In short, you have to put in a lot of the work yourself, or use a framework/library, because you cannot rely on the browser to do it for you.
Various libraries and plugins for localization:
Feel free to add/edit.
How to break out or exit a method in Java?
Use the return keyword to exit from a method.
public void someMethod() {
//... a bunch of code ...
if (someCondition()) {
return;
}
//... otherwise do the following...
}
Pls note:
We may use break statements which are used to break/exit only from a loop, and not the entire program.
To exit from program: System.exit() Method:
System.exit has status code, which tells about the termination, such as:
exit(0) : Indicates successful termination.
exit(1) or exit(-1) or any non-zero value – indicates unsuccessful termination.
What's the most appropriate HTTP status code for an "item not found" error page
A 404 return code actually means 'resource not found', and applies to any entity for which a request was made but not satisfied. So it works equally-well for pages, subsections of pages, and any item that exists on the page which has a specific request to be rendered.
So 404 is the right code to use in this scenario. Note that it doesn't apply to 'server not found', which is a different situation in which a request was issued but not answered at all, as opposed to answered but without the resource requested.
WHERE IS NULL, IS NOT NULL or NO WHERE clause depending on SQL Server parameter value
Here is how you can solve this using a single WHERE clause:
WHERE (@myParm = value1 AND MyColumn IS NULL)
OR (@myParm = value2 AND MyColumn IS NOT NULL)
OR (@myParm = value3)
A naïve usage of the CASE statement does not work, by this I mean the following:
SELECT Field1, Field2 FROM MyTable
WHERE CASE @myParam
WHEN value1 THEN MyColumn IS NULL
WHEN value2 THEN MyColumn IS NOT NULL
WHEN value3 THEN TRUE
END
It is possible to solve this using a case statement, see onedaywhen's answer
How to npm install to a specified directory?
In the documentation it's stated:
Use the prefix option together with the global option:
The prefix config defaults to the location where node is installed. On
most systems, this is /usr/local. On windows, this is the exact
location of the node.exe binary. On Unix systems, it's one level up,
since node is typically installed at {prefix}/bin/node rather than
{prefix}/node.exe.
When the global flag is set, npm installs things into this prefix.
When it is not set, it uses the root of the current package, or the
current working directory if not in a package already.
(Emphasis by them)
So in your root directory you could install with
npm install --prefix <path/to/prefix_folder> -g
and it will install the node_modules folder into the folder
<path/to/prefix_folder>/lib/node_modules
Detecting scroll direction
You can try doing this.
_x000D_
_x000D_
function scrollDetect(){_x000D_
var lastScroll = 0;_x000D_
_x000D_
window.onscroll = function() {_x000D_
let currentScroll = document.documentElement.scrollTop || document.body.scrollTop; // Get Current Scroll Value_x000D_
_x000D_
if (currentScroll > 0 && lastScroll <= currentScroll){_x000D_
lastScroll = currentScroll;_x000D_
document.getElementById("scrollLoc").innerHTML = "Scrolling DOWN";_x000D_
}else{_x000D_
lastScroll = currentScroll;_x000D_
document.getElementById("scrollLoc").innerHTML = "Scrolling UP";_x000D_
}_x000D_
};_x000D_
}_x000D_
_x000D_
_x000D_
scrollDetect();
_x000D_
html,body{_x000D_
height:100%;_x000D_
width:100%;_x000D_
margin:0;_x000D_
padding:0;_x000D_
}_x000D_
_x000D_
.cont{_x000D_
height:100%;_x000D_
width:100%;_x000D_
}_x000D_
_x000D_
.item{_x000D_
margin:0;_x000D_
padding:0;_x000D_
height:100%;_x000D_
width:100%;_x000D_
background: #ffad33;_x000D_
}_x000D_
_x000D_
.red{_x000D_
background: red;_x000D_
}_x000D_
_x000D_
p{_x000D_
position:fixed;_x000D_
font-size:25px;_x000D_
top:5%;_x000D_
left:5%;_x000D_
}
_x000D_
<div class="cont">_x000D_
<div class="item"></div>_x000D_
<div class="item red"></div>_x000D_
<p id="scrollLoc">0</p>_x000D_
</div>
_x000D_
_x000D_
_x000D_
MySQL: Delete all rows older than 10 minutes
If time_created is a unix timestamp (int), you should be able to use something like this:
DELETE FROM locks WHERE time_created < (UNIX_TIMESTAMP() - 600);
(600 seconds = 10 minutes - obviously)
Otherwise (if time_created is mysql timestamp), you could try this:
DELETE FROM locks WHERE time_created < (NOW() - INTERVAL 10 MINUTE)
SyntaxError: Cannot use import statement outside a module
If anyone is running into this issue with Typescript, the key to solving it for me was changing
"target": "esnext",
"module": "esnext",
to
"target": "esnext",
"module": "commonjs",
In my tsconfig.json. I was under the impression "esnext" was the "best", but that was just a mistake.
Choosing line type and color in Gnuplot 4.0
I've ran into this topic, because i was struggling with dashed lines too (gnuplot 4.6 patchlevel 0)
If you use:
set termoption dashed
Your posted code will work accordingly.
Related question:
However, if I want to export a png with:
set terminal png, this isn't working anymore. Anyone got a clue why?
Turns out, out, gnuplots png export library doesnt support this.
Possbile solutions:
- one can simply export to ps, then convert it with pstopng
- according to @christoph, if you use
pngcairo as your terminal (set terminal pngcairo) it will work
Class Not Found: Empty Test Suite in IntelliJ
I had a similar problem after starting a new IntelliJ project. I found that the "module compile output path" for my module was not properly specified. When I assigned the path in the module's "compile output path" to the proper location, the problem was solved. The compile output path is assigned in the Project settings. Under Modules, select the module involved and select the Paths tab...
Paths tab in the Project Settings | Modules dialog
...I sent the compiler output to a folder named "output" that is present in the parent Project folder.
How to create a backup of a single table in a postgres database?
I was trying to run pg_dump from within psql command prompt and I was not able to trace output file anywhere on my ubuntu 20.04 box. I tried finding by find / -name "myfilename.sql".
Instead When I tried pg_dump from /home/ubuntu, I found my output file in /home/ubuntu
GROUP_CONCAT comma separator - MySQL
Looks like you're missing the SEPARATOR keyword in the GROUP_CONCAT function.
GROUP_CONCAT(artists.artistname SEPARATOR '----')
The way you've written it, you're concatenating artists.artistname with the '----' string using the default comma separator.
Is ncurses available for windows?
Such a thing probably does not exist "as-is". It doesn't really exist on Linux or other UNIX-like operating systems either though.
ncurses is only a library that helps you manage interactions with the underlying terminal environment. But it doesn't provide a terminal emulator itself.
The thing that actually displays stuff on the screen (which in your requirement is listed as "native resizable win32 windows") is usually called a Terminal Emulator. If you don't like the one that comes with Windows (you aren't alone; no person on Earth does) there are a few alternatives. There is Console, which in my experience works sometimes and appears to just wrap an underlying Windows terminal emulator (I don't know for sure, but I'm guessing, since there is a menu option to actually get access to that underlying terminal emulator, and sure enough an old crusty Windows/DOS box appears which mirrors everything in the Console window).
A better option
Another option, which may be more appealing is puttycyg. It hooks in to Putty (which, coming from a Linux background, is pretty close to what I'm used to, and free) but actually accesses an underlying cygwin instead of the Windows command interpreter (CMD.EXE). So you get all the benefits of Putty's awesome terminal emulator, as well as nice ncurses (and many other) libraries provided by cygwin. Add a couple command line arguments to the Shortcut that launches Putty (or the Batch file) and your app can be automatically launched without going through Putty's UI.
Define the selected option with the old input in Laravel / Blade
Okay, my 2 cents, using the default value of Laravel's old() function.
<select name="type">
@foreach($options as $key => $text)
<option @if((int) old('type', $selectedOption) === $key) selected @endif value="{{ $key }}">{{ $text }}</option>
@endforeach
</select>
Java String array: is there a size of method?
Also, it's probably useful to note that if you have a multiple dimensional Array, you can get the respective dimension just by appending a '[0]' to the array you are querying until you arrive at the appropriate axis/tuple/dimension.
This is probably better explained with the following code:
public class Test {
public static void main(String[] args){
String[][] moo = new String[5][12];
System.out.println(moo.length); //Prints the size of the First Dimension in the array
System.out.println(moo[0].length);//Prints the size of the Second Dimension in the array
}
}
Which produces the output:
5
12
Python subprocess/Popen with a modified environment
That depends on what the issue is. If it's to clone and modify the environment one solution could be:
subprocess.Popen(my_command, env=dict(os.environ, PATH="path"))
But that somewhat depends on that the replaced variables are valid python identifiers, which they most often are (how often do you run into environment variable names that are not alphanumeric+underscore or variables that starts with a number?).
Otherwise you'll could write something like:
subprocess.Popen(my_command, env=dict(os.environ,
**{"Not valid python name":"value"}))
In the very odd case (how often do you use control codes or non-ascii characters in environment variable names?) that the keys of the environment are bytes you can't (on python3) even use that construct.
As you can see the techniques (especially the first) used here benefits on the keys of the environment normally is valid python identifiers, and also known in advance (at coding time), the second approach has issues. In cases where that isn't the case you should probably look for another approach.
Disabled href tag
There is no disabled attribute for hyperlinks. If you don't want something to be linked then you'll need to remove the <a> tag altogether.
Alternatively you can remove its href attribute - though this has other UX and Accessibility issues as noted in the comments below so is not recommended.
How to find first element of array matching a boolean condition in JavaScript?
I have got inspiration from multiple sources on the internet to derive into the solution below. Wanted to take into account both some default value and to provide a way to compare each entry for a generic approach which this solves.
Usage: (giving value "Second")
var defaultItemValue = { id: -1, name: "Undefined" };
var containers: Container[] = [{ id: 1, name: "First" }, { id: 2, name: "Second" }];
GetContainer(2).name;
Implementation:
class Container {
id: number;
name: string;
}
public GetContainer(containerId: number): Container {
var comparator = (item: Container): boolean => {
return item.id == containerId;
};
return this.Get<Container>(this.containers, comparator, this.defaultItemValue);
}
private Get<T>(array: T[], comparator: (item: T) => boolean, defaultValue: T): T {
var found: T = null;
array.some(function(element, index) {
if (comparator(element)) {
found = element;
return true;
}
});
if (!found) {
found = defaultValue;
}
return found;
}
Python Regex - How to Get Positions and Values of Matches
For Python 3.x
from re import finditer
for match in finditer("pattern", "string"):
print(match.span(), match.group())
You shall get \n separated tuples (comprising first and last indices of the match, respectively) and the match itself, for each hit in the string.
TypeError : Unhashable type
... and so you should do something like this:
set(tuple ((a,b) for a in range(3)) for b in range(3))
... and if needed convert back to list
Url.Action parameters?
This works for MVC 5:
<a href="@Url.Action("ActionName", "ControllerName", new { paramName1 = item.paramValue1, paramName2 = item.paramValue2 })" >
Link text
</a>
Declaring and using MySQL varchar variables
Looks like you forgot the @ in variable declaration. Also I remember having problems with SET in MySql a long time ago.
Try
DECLARE @FOO varchar(7);
DECLARE @oldFOO varchar(7);
SELECT @FOO = '138';
SELECT @oldFOO = CONCAT('0', @FOO);
update mypermits
set person = @FOO
where person = @oldFOO;
How do I watch a file for changes?
Did you try using Watchdog?
Python API library and shell utilities to monitor file system events.
Directory monitoring made easy with
- A cross-platform API.
- A shell tool to run commands in response to directory changes.
Get started quickly with a simple example in Quickstart...
Python concatenate text files
What's wrong with UNIX commands ? (given you're not working on Windows) :
ls | xargs cat | tee output.txt does the job ( you can call it from python with subprocess if you want)
How to avoid the "Windows Defender SmartScreen prevented an unrecognized app from starting warning"
If you have a standard code signing certificate, some time will be needed for your application to build trust. Microsoft affirms that an Extended Validation (EV) Code Signing Certificate allows us to skip this period of trust-building. According to Microsoft, extended validation certificates allow the developer to immediately establish a reputation with SmartScreen. Otherwise, the users will see a warning like "Windows Defender SmartScreen prevented an unrecognized app from starting. Running this app might put your PC at risk.", with the two buttons: "Run anyway" and "Don't run".
Another Microsoft resource states the following (quote): "Although not required, programs signed by an EV code signing certificate can immediately establish a reputation with SmartScreen reputation services even if no prior reputation exists for that file or publisher. EV code signing certificates also have a unique identifier which makes it easier to maintain reputation across certificate renewals."
My experience is as follows. Since 2005, we have been using regular (non-EV) code signing certificates to sign .MSI, .EXE and .DLL files with time stamps, and there has never been a problem with SmartScreen until 2018, when there was just one case when it took 3 days for a beta version of our application to build trust since we have released it to beta testers, and it was in the middle of certificate validity period. I don't know what SmartScreen might not like in that specific version of our application, but there have been no SmartScreen complaints since then. Therefore, if your certificate is a non-EV, it is a signed application (such as an .MSI file) that will build trust over time, not a certificate. For example, a certificate can be issued a few months ago and used to sign many files, but for each signed file you publish, it may take a few days for SmartScreen to stop complaining about the file after publishing, as was in our case in 2018.
As a conclusion, to avoid the warning completely, i.e. prevent it from happening even suddenly, you need an Extended Validation (EV) code signing certificate.
C++ sorting and keeping track of indexes
I wrote generic version of index sort.
template <class RAIter, class Compare>
void argsort(RAIter iterBegin, RAIter iterEnd, Compare comp,
std::vector<size_t>& indexes) {
std::vector< std::pair<size_t,RAIter> > pv ;
pv.reserve(iterEnd - iterBegin) ;
RAIter iter ;
size_t k ;
for (iter = iterBegin, k = 0 ; iter != iterEnd ; iter++, k++) {
pv.push_back( std::pair<int,RAIter>(k,iter) ) ;
}
std::sort(pv.begin(), pv.end(),
[&comp](const std::pair<size_t,RAIter>& a, const std::pair<size_t,RAIter>& b) -> bool
{ return comp(*a.second, *b.second) ; }) ;
indexes.resize(pv.size()) ;
std::transform(pv.begin(), pv.end(), indexes.begin(),
[](const std::pair<size_t,RAIter>& a) -> size_t { return a.first ; }) ;
}
Usage is the same as that of std::sort except for an index container to receive sorted indexes.
testing:
int a[] = { 3, 1, 0, 4 } ;
std::vector<size_t> indexes ;
argsort(a, a + sizeof(a) / sizeof(a[0]), std::less<int>(), indexes) ;
for (size_t i : indexes) printf("%d\n", int(i)) ;
you should get 2 1 0 3.
for the compilers without c++0x support, replace the lamba expression as a class template:
template <class RAIter, class Compare>
class PairComp {
public:
Compare comp ;
PairComp(Compare comp_) : comp(comp_) {}
bool operator() (const std::pair<size_t,RAIter>& a,
const std::pair<size_t,RAIter>& b) const { return comp(*a.second, *b.second) ; }
} ;
and rewrite std::sort as
std::sort(pv.begin(), pv.end(), PairComp(comp)()) ;
Create a sample login page using servlet and JSP?
You're comparing the message with the empty string using ==.
First, your comparison is wrong because the message will be null (and not the empty string).
Second, it's wrong because Objects must be compared with equals() and not with ==.
Third, it's wrong because you should avoid scriptlets in JSP, and use the JSP EL, the JSTL, and other custom tags instead:
<c:id test="${!empty message}">
<c:out value="${message}"/>
</c:if>
submitting a form when a checkbox is checked
You can submit form by just clicking on checkbox by simple method in JavaScript.
Inside form tag or Input attribute add following attribute:
onchange="this.form.submit()"
Example:
<form>
<div>
<input type="checkbox">
</div>
</form>
java.util.regex - importance of Pattern.compile()?
Pattern.compile() allow to reuse a regex multiple times (it is threadsafe). The performance benefit can be quite significant.
I did a quick benchmark:
@Test
public void recompile() {
var before = Instant.now();
for (int i = 0; i < 1_000_000; i++) {
Pattern.compile("ab").matcher("abcde").matches();
}
System.out.println("recompile " + Duration.between(before, Instant.now()));
}
@Test
public void compileOnce() {
var pattern = Pattern.compile("ab");
var before = Instant.now();
for (int i = 0; i < 1_000_000; i++) {
pattern.matcher("abcde").matches();
}
System.out.println("compile once " + Duration.between(before, Instant.now()));
}
compileOnce was between 3x and 4x faster.
I guess it highly depends on the regex itself but for a regex that is often used, I go for a static Pattern pattern = Pattern.compile(...)
Setting Elastic search limit to "unlimited"
From the docs, "Note that from + size can not be more than the index.max_result_window index setting which defaults to 10,000". So my admittedly very ad-hoc solution is to just pass size: 10000 or 10,000 minus from if I use the from argument.
Note that following Matt's comment below, the proper way to do this if you have a larger amount of documents is to use the scroll api. I have used this successfully, but only with the python interface.
How do I get extra data from intent on Android?
You can get any type of extra data from intent, no matter if it's an object or string or any type of data.
Bundle extra = getIntent().getExtras();
if (extra != null){
String str1 = (String) extra.get("obj"); // get a object
String str2 = extra.getString("string"); //get a string
}
and the Shortest solution is:
Boolean isGranted = getIntent().getBooleanExtra("tag", false);
How to create a file with a given size in Linux?
There are lots of answers, but none explained nicely what else can be done. Looking into man pages for dd, it is possible to better specify the size of a file.
This is going to create /tmp/zero_big_data_file.bin filled with zeros, that has size of 20 megabytes :
dd if=/dev/zero of=/tmp/zero_big_data_file.bin bs=1M count=20
This is going to create /tmp/zero_1000bytes_data_file.bin filled with zeros, that has size of 1000 bytes :
dd if=/dev/zero of=/tmp/zero_1000bytes_data_file.bin bs=1kB count=1
or
dd if=/dev/zero of=/tmp/zero_1000bytes_data_file.bin bs=1000 count=1
- In all examples, bs is block size, and count is number of blocks
- BLOCKS and BYTES may be followed by the following multiplicative suffixes: c =1, w =2, b =512, kB =1000, K =1024, MB =1000*1000, M =1024*1024, xM =M GB =1000*1000*1000, G =1024*1024*1024, and so on for T, P, E, Z, Y.
jQuery-UI datepicker default date
Try passing in a Date object instead. I can't see why it doesn't work in the format you have entered:
<script type="text/javascript">
$(function() {
$("#birthdate" ).datepicker({
changeMonth: true,
changeYear: true,
yearRange: '1920:2010',
dateFormat : 'dd-mm-yy',
defaultDate: new Date(1985, 00, 01)
});
});
</script>
http://api.jqueryui.com/datepicker/#option-defaultDate
Specify either an actual date via a
Date object or as a string in the
current dateFormat, or a number of
days from today (e.g. +7) or a string
of values and periods ('y' for years,
'm' for months, 'w' for weeks, 'd' for
days, e.g. '+1m +7d'), or null for
today.
How to use if statements in underscore.js templates?
This should do the trick:
<% if (typeof(date) !== "undefined") { %>
<span class="date"><%= date %></span>
<% } %>
Remember that in underscore.js templates if and for are just standard javascript syntax wrapped in <% %> tags.
What is the height of iPhone's onscreen keyboard?
I can't find latest answer, so I check it all with simulator.(iOS 11.0)
Device | Screen Height | Portrait | Landscape
iPhone 4s | 480.0 | 216.0 | 162.0
iPhone 5, iPhone 5s, iPhone SE | 568.0 | 216.0 | 162.0
iPhone 6, iPhone 6s, iPhone 7, iPhone 8, iPhone X | 667.0 | 216.0 | 162.0
iPhone 6 plus, iPhone 7 plus, iPhone 8 plus | 736.0 | 226.0 | 162.0
iPad 5th generation, iPad Air, iPad Air 2, iPad Pro 9.7, iPad Pro 10.5, iPad Pro 12.9 | 1024.0 | 265.0 | 353.0
Thanks!
JavaScript null check
I think, testing variables for values you do not expect is not a good idea in general. Because the test as your you can consider as writing a blacklist of forbidden values. But what if you forget to list all the forbidden values? Someone, even you, can crack your code with passing an unexpected value. So a more appropriate approach is something like whitelisting - testing variables only for the expected values, not unexpected. For example, if you expect the data value to be a string, instead of this:
function (data) {
if (data != null && data !== undefined) {
// some code here
// but what if data === false?
// or data === '' - empty string?
}
}
do something like this:
function (data) {
if (typeof data === 'string' && data.length) {
// consume string here, it is here for sure
// cleaner, it is obvious what type you expect
// safer, less error prone due to implicit coercion
}
}
How to select ALL children (in any level) from a parent in jQuery?
Use jQuery.find() to find children more than one level deep.
The .find() and .children() methods are similar, except that the
latter only travels a single level down the DOM tree.
$('#google_translate_element').find('*').unbind('click');
You need the '*' in find():
Unlike in the rest of the tree traversal methods, the selector
expression is required in a call to .find(). If we need to retrieve
all of the descendant elements, we can pass in the universal selector
'*' to accomplish this.
Adding an item to an associative array
For anyone that also need to add into 2d associative array, you can also use answer given above, and use the code like this
$data[$category]["test"] = $question
you can then call it (to test out the result by:
echo $data[$category]["test"];
which should print $question
