Programs & Examples On #Inproc

HTTP Error 500.30 - ANCM In-Process Start Failure

In may case it was just a typo which corrupts and prevents parsing of JSON settings file

Android Gradle 5.0 Update:Cause: org.jetbrains.plugins.gradle.tooling.util

I solved this issue after changing the "Gradle Version" and "Android Plugin version".

You just goto "File>>Project Structure>>Project>>" and make changes here. I have worked a combination of versions from another working project of mine and added to the Project where I was getting this problem.

Execution failed for task ':app:compileDebugJavaWithJavac' Android Studio 3.1 Update

Not sure if this solution works for you or not but just want to heads you up on compiler and build tools version compatibility issues.

This could be because of Java and Gradle version mismatch.

distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-all.zip

Gradle 4.4 is compatible with only Java 7 and 8. So, point your global variable JAVA_HOME to Java 7 or 8.

In mac, add below line to your ~/.bash_profile

export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk1.8.0_191.jdk/Contents/Home

You can have multiple java versions. Just change the JAVA_HOME path based on need. You can do it easily, check this

Error:Execution failed for task ':app:compileDebugKotlin'. > Compilation error. See log for more details

My scenario:

old Kotlin dataclass:

data class AddHotelParams(val destination: Place?, val checkInDate: LocalDate,
                      val checkOutDate: LocalDate?): JsonObject

new Kotlin dataclass:

data class AddHotelParams(val destination: Place?, val checkInDate: LocalDate,
                      val checkOutDate: LocalDate?, val roundTrip: Boolean): JsonObject

The problem was that I forgot to change the object initialization in some parts of the code. I got a generic "compileInternalDebugKotlin" error instead of being told where I needed to change the initialization.

changing initialization to all parts of the code resolved the error.

org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:transformClassesWithDexForDebug'

Just a simple solution is here...it worked for me:

  1. Clean Project
  2. Rebuild project
  3. Sync project with gradle file

Android- Error:Execution failed for task ':app:transformClassesWithDexForRelease'

I have just written this code into gradle.properties and it is ok now

org.gradle.jvmargs=-XX:MaxHeapSize\=2048m -Xmx2048m

Forward X11 failed: Network error: Connection refused

PuTTY can't find where your X server is, because you didn't tell it. (ssh on Linux doesn't have this problem because it runs under X so it just uses that one.) Fill in the blank box after "X display location" with your Xming server's address.

Alternatively, try MobaXterm. It has an X server builtin.

configuring project ':app' failed to find Build Tools revision

also try to increase gradle version in your project's build.gradle. It helped me

Error LNK2019 unresolved external symbol _main referenced in function "int __cdecl invoke_main(void)" (?invoke_main@@YAHXZ)

I deleted the file with main() function in my project when I wanted to change project type to static library.

I Forgot to change Properties -> General -> Configuration Type

from

Application(.exe)

to

Static Library (.lib)

This too gave me the same error.

No tests found for given includes Error, when running Parameterized Unit test in Android Studio

You could check if your method is private. Spent a lot of time fixing this dumb mistake ...

Error:Execution failed for task ':ProjectName:mergeDebugResources'. > Crunching Cruncher *some file* failed, see logs

I had the same problem.

It was caused by a corrupted file. If you added some new Drawable before getting this error, check them to see if they are correctly display in Android Studio Viewer.

Spring Maven clean error - The requested profile "pom.xml" could not be activated because it does not exist

Goto Properties -> maven Remove the pom.xml from the activate profiles and follow the below steps.

Steps :

  1. Delete the .m2 repository
  2. Restart the Eclipse IDE
  3. Refresh and Rebuild it

Spring Boot - Error creating bean with name 'dataSource' defined in class path resource

In my case I just ignored the following in application.properties file:

# Hibernate

#spring.jpa.hibernate.ddl-auto=update

It works for me....

The OLE DB provider "Microsoft.ACE.OLEDB.12.0" for linked server "(null)"

This is for my reference, as I encountered a variety of SQL error messages while trying to connect with provider. Other answers prescribe "try this, then this, then this". I appreciate the other answers, but I like to pair specific solutions with specific problems


Error

...provider did not give information...Cannot initialize data source object...

Error Numbers

7399, 7303

Error Detail

Msg 7399, Level 16, State 1, Line 2 The OLE DB provider "Microsoft.ACE.OLEDB.12.0" for linked server "(null)" reported an error. 
  The provider did not give any information about the error. 
Msg 7303, Level 16, State 1, Line 2 Cannot initialize the data source object
  of OLE DB provider "Microsoft.ACE.OLEDB.12.0" for linked server "(null)".

Solution

File was open. Close it.

Credit


Error

Access denied...Cannot get the column information...

Error Numbers

7399, 7350

Error Detail

Msg 7399, Level 16, State 1, Line 2 The OLE DB provider "Microsoft.ACE.OLEDB.12.0" for linked server "(null)" reported an error. 
  Access denied.
Msg 7350, Level 16, State 2, Line 2 Cannot get the column information 
  from OLE DB provider "Microsoft.ACE.OLEDB.12.0" for linked server "(null)".

Solution

Give access

Credit


Error

No value given for one or more required parameters....Cannot execute the query ...

Error Numbers

???, 7320

Error Detail

OLE DB provider "Microsoft.ACE.OLEDB.12.0" for linked server "(null)" returned message "No value given for one or more required parameters.".
Msg 7320, Level 16, State 2, Line 2
Cannot execute the query "select [Col A], [Col A] FROM $Sheet" against OLE DB provider "Microsoft.ACE.OLEDB.12.0" for linked server "(null)". 

Solution

Column names might be wrong. Do [Col A] and [Col B] actually exist in your spreadsheet?


Error

"Unspecified error"...Cannot initialize data source object...

Error Numbers

???, 7303

Error Detail

OLE DB provider "Microsoft.ACE.OLEDB.12.0" for linked server "(null)" returned message "Unspecified error".
Msg 7303, Level 16, State 1, Line 2 Cannot initialize the data source object of OLE DB provider "Microsoft.ACE.OLEDB.12.0" for linked server "(null)".

Solution

Run SSMS as admin. See this question.


Other References

Other answers which suggest modifying properties. Not sure how modifying these two properties (checking them or unchecking them) would help.

Serving static web resources in Spring Boot & Spring Security application

@Configuration
@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

    @Override
    protected void configure(HttpSecurity http) throws Exception {

        String[] resources = new String[]{
                "/", "/home","/pictureCheckCode","/include/**",
                "/css/**","/icons/**","/images/**","/js/**","/layer/**"
        };

        http.authorizeRequests()
                .antMatchers(resources).permitAll()
                .anyRequest().authenticated()
                .and()
            .formLogin()
                .loginPage("/login")
                .permitAll()
                .and()
            .logout().logoutUrl("/404")
                .permitAll();
        super.configure(http);
    }
}

System.Data.SqlClient.SqlException: Login failed for user

I tried some of the suggested answers but it didn't resolve the issue. Finally I found out that the default connection timeout (not command timeout) is 15 seconds and once I increased it to 60 it almost never happened again. simply add this to you connection string: ;Connection Timeout=60 I chose 60 seconds but you can put any value you think would fit the best to your needs.

Gradle: Execution failed for task ':processDebugManifest'

I came across similar problem ,when I run

cordova build android

which report errors:

 /home/app/phonegap/helloworld/platforms/android/AndroidManifest.xml:15:5 Error:
uses-sdk:minSdkVersion 7 cannot be smaller than version 10 declared in library  /home/app/phonegap/helloworld/platforms/android/build/intermediates/exploded-aar/android/CordovaLib/unspecified/debug/AndroidManifest.xml
Suggestion: use tools:overrideLibrary="org.apache.cordova" to force usage

:processDebugManifest FAILED

FAILURE: Build failed with an exception.

  • What went wrong: Execution failed for task ':processDebugManifest'.

    Manifest merger failed : uses-sdk:minSdkVersion 7 cannot be smaller than version 10 declared in library /home/app/phonegap/helloworld/platforms/android/build/intermediates/exploded-aar/android/CordovaLib/unspecified/debug/AndroidManifest.xml Suggestion: use tools:overrideLibrary="org.apache.cordova" to force usage

In my case,

uses-sdk:minSdkVersion 7 cannot be smaller than version 10 declared

,above solution do not work! but I solve them by replace

<preference name="android-minSdkVersion" value="7" />

as

<preference name="android-minSdkVersion" value="10" />

in this two file /home/app/phonegap/helloworld/config.xml , /home/app/phonegap/helloworld/platforms/android/res/xml/config.xml

403 - Forbidden: Access is denied. You do not have permission to view this directory or page using the credentials that you supplied

I had the same problem. It turned out that I didn't specify a default page and I didn't have any page that is named after the default page convention (default.html, defult.aspx etc). As a result, ASP.NET doesn't allow the user to browse the directory (not a problem in Visual Studio built-in web server that allows you to view the directory) and shows the error message. To fix it, I added one default page in Web.Config and it worked.

<system.webServer>
    <defaultDocument>
        <files>
            <add value="myDefault.aspx"/>
        </files>
    </defaultDocument>
</system.webServer>

MySql Inner Join with WHERE clause

Yes you are right. You have placed WHERE clause wrong. You can only use one WHERE clause in single query so try AND for multiple conditions like this:

 SELECT table1.f_id  FROM table1 
   INNER JOIN table2
     ON table2.f_id = table1.f_id
 WHERE table2.f_type = 'InProcess'
   AND f_com_id = '430'
   AND f_status = 'Submitted' 

The type or namespace name does not exist in the namespace 'System.Web.Mvc'

I have deleted System.Web.dll from Bin frolder of my site.

Celery Received unregistered task of type (run example)

app = Celery('proj',
             broker='amqp://',
             backend='amqp://',
             include=['proj.tasks'])

please include=['proj.tasks'] You need go to the top dir, then exec this

celery -A app.celery_module.celeryapp worker --loglevel=info

not

celery -A celeryapp worker --loglevel=info

in your celeryconfig.py input imports = ("path.ptah.tasks",)

please in other module invoke task!!!!!!!!

Where is the Global.asax.cs file?

That's because you created a Web Site instead of a Web Application. The cs/vb files can only be seen in a Web Application, but in a website you can't have a separate cs/vb file.

Edit: In the website you can add a cs file behavior like..

<%@ Application CodeFile="Global.asax.cs" Inherits="ApplicationName.MyApplication" Language="C#" %>

~/Global.asax.cs:

namespace ApplicationName
{
    public partial class MyApplication : System.Web.HttpApplication
    {
        protected void Application_Start()
        {
        }
    }
}

Losing Session State

Your session is lost becoz....

I have found a scenario where session is lost - In a asp.net page, for a amount text box field has invalid characters, and followed by a session variable retrieval for other purpose.After posting the invalid number parsing through Convert.ToInt32 or double raises a first chance exception, but error does not show at that line, Instead of that, Session being null because of unhandled exception, shows error at session retrieval, thus deceiving the debugging...

HINT: Test your system to fail it- DESTRUCTIVE.. enter enough junk in unrelated scenarios for ex: after search results shown enter junk in search criteria and goto details of search result... , you would be able to reproduce this machine on your local code base too...:)

Hope it Helps, hydtechie

JUnit tests pass in Eclipse but fail in Maven Surefire

I had a similar problem with a different cause and therefore different solution. In my case, I actually had an error where a singleton object was having a member variable modified in a non-threadsafe way. In this case, following the accepted answers and circumventing the parallel testing would only hide the error that was actually revealed by the test. My solution, of course, is to fix the design so that I don't have this bad behavior in my code.

"java.lang.OutOfMemoryError: PermGen space" in Maven build

If you want to make this part of your POM for a repeatable build, you can use the fork-variant of a few of the plugins (especially compiler:compile and surefire:test):

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.2</version>
    <configuration>
      <fork>true</fork>
      <meminitial>128m</meminitial>
      <maxmem>1024m</maxmem>
      <compilerArgs>
        <arg>-XX:MaxPermSize=256m</arg>
      </compilerArgs>
    </configuration>
  </plugin>

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>2.18</version>
    <configuration>
        <forkCount>1</forkCount>
        <argLine>-Xmx1024m -XX:MaxPermSize=256m</argLine>
    </configuration>
</plugin>

Server cannot set status after HTTP headers have been sent IIS7.5

I had the same issue with setting StatusCode and then Response.End in HandleUnauthorizedRequest method of AuthorizeAttribute

var ctx = filterContext.HttpContext;
ctx.Response.StatusCode = (int)HttpStatusCode.Forbidden;
ctx.Response.End();

If you are using .NET 4.5+, add this line before Response.StatusCode

filterContext.HttpContext.Response.SuppressFormsAuthenticationRedirect = true;

If you are using .NET 4.0, try SuppressFormsAuthenticationRedirectModule.

How to set session timeout in web.config

If you want to set the timeout to 20 minutes, use something like this:

    <configuration>
      <system.web>
         <sessionState timeout="20"></sessionState>
      </system.web>
    </configuration>

Return 0 if field is null in MySQL

You can use coalesce(column_name,0) instead of just column_name. The coalesce function returns the first non-NULL value in the list.

I should mention that per-row functions like this are usually problematic for scalability. If you think your database may get to be a decent size, it's often better to use extra columns and triggers to move the cost from the select to the insert/update.

This amortises the cost assuming your database is read more often than written (and most of them are).

How to create our own Listener interface in android?

Create listener interface.

public interface YourCustomListener
{
    public void onCustomClick(View view);
            // pass view as argument or whatever you want.
}

And create method setOnCustomClick in another activity(or fragment) , where you want to apply your custom listener......

  public void setCustomClickListener(YourCustomListener yourCustomListener)
{
    this.yourCustomListener= yourCustomListener;
}

Call this method from your First activity, and pass the listener interface...

SSL Proxy/Charles and Android trouble

The top rated answers are working perfect (a bit old but still working), but I just want to mention that since Android N we all can configure your apps in order to have diff trust SSL certificates (for release , debug only and so on), including Charles SSL Proxy certificate (if you download the Charles certificate and put .pem file in your raw folder). More info can be found here: https://developer.android.com/training/articles/security-config.html

Also the official Charles documentation can be useful to setup this : https://www.charlesproxy.com/documentation/using-charles/ssl-certificates/

Hope this will help to setup Charles inside your app project not on every single Android device.

What is the meaning of git reset --hard origin/master?

git reset --hard origin/master

says: throw away all my staged and unstaged changes, forget everything on my current local branch and make it exactly the same as origin/master.

You probably wanted to ask this before you ran the command. The destructive nature is hinted at by using the same words as in "hard reset".

Python pip install module is not found. How to link python to pip location?

For the sake of anyone also using visual studio from a windows environment:

I realized that I could see my module installed when i ran pip install

py pip install [moduleName] 
py pip list

However debugging in visual studio was getting "module not found". Oddly, i was successfully running import [moduleName] when i ran the interpreter in powershell.

Reason:

visual studio was using the wrong interpreter at: C:\Users\[username]\AppData\Local\Programs\Python\Python37\

What I REALLY wanted was visual studio to use the virtualenv that i setup for my project. To do this, right click Python Environments in "solution explorer", select Add Virtual Environment..., and then select the folder where you created your virtual environment. enter image description here Then, under project settings, under the General tab, select your virtual environment in the dropdown.

enter image description here

Now visual studio should be using the same interpreter and everything should play nice!

Clear icon inside input text

Could I suggest, if you're okay with this being limited to html 5 compliant browsers, simply using:

<input type="search" />

JS Fiddle demo

Admittedly, in Chromium (Ubuntu 11.04), this does require there to be text inside the input element before the clear-text image/functionality will appear.

Reference:

Database corruption with MariaDB : Table doesn't exist in engine

Something has deleted your ibdata1 file where InnoDB keeps the dictionary. Definitely it's not MySQL who does it.

UPDATE: I made a tutorial on how to fix the error - https://youtu.be/014KbCYayuE

Matplotlib - global legend and title aside subplots

suptitle seems the way to go, but for what it's worth, the figure has a transFigure property that you can use:

fig=figure(1)
text(0.5, 0.95, 'test', transform=fig.transFigure, horizontalalignment='center')

Access blocked by CORS policy: Response to preflight request doesn't pass access control check

If you are using Spring as Back-End server and especially using Spring Security then i found a solution by putting http.cors(); in the configure method. The method looks like that:

protected void configure(HttpSecurity http) throws Exception {
        http
                .csrf().disable()
                .authorizeRequests() // authorize
                .anyRequest().authenticated() // all requests are authenticated
                .and()
                .httpBasic();

        http.cors();
}

Setting mime type for excel document

I am using EPPlus to generate .xlsx (OpenXML format based) excel file. For sending this excel file as attachment in email I use the following MIME type and it works fine with EPPlus generated file and opens properly in ms-outlook mail client preview.

string mimeType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
System.Net.Mime.ContentType contentType = null;
if (mimeType?.Length > 0)
{
    contentType = new System.Net.Mime.ContentType(mimeType);
}

How to access the contents of a vector from a pointer to the vector in C++?

Do you have a pointer to a vector because that's how you've coded it? You may want to reconsider this and use a (possibly const) reference. For example:

#include <iostream>
#include <vector>

using namespace std;

void foo(vector<int>* a)
{
    cout << a->at(0) << a->at(1) << a->at(2) << endl;
    // expected result is "123"
}

int main()
{
    vector<int> a;
    a.push_back(1);
    a.push_back(2);
    a.push_back(3);

    foo(&a);
}

While this is a valid program, the general C++ style is to pass a vector by reference rather than by pointer. This will be just as efficient, but then you don't have to deal with possibly null pointers and memory allocation/cleanup, etc. Use a const reference if you aren't going to modify the vector, and a non-const reference if you do need to make modifications.

Here's the references version of the above program:

#include <iostream>
#include <vector>

using namespace std;

void foo(const vector<int>& a)
{
    cout << a[0] << a[1] << a[2] << endl;
    // expected result is "123"
}

int main()
{
    vector<int> a;
    a.push_back(1);
    a.push_back(2);
    a.push_back(3);

    foo(a);
}

As you can see, all of the information contained within a will be passed to the function foo, but it will not copy an entirely new value, since it is being passed by reference. It is therefore just as efficient as passing by pointer, and you can use it as a normal value rather than having to figure out how to use it as a pointer or having to dereference it.

Visual Studio keyboard shortcut to display IntelliSense

On Visual Studio Community 7.5.3 on Mac this works for me:

Ctrl + Space

Where is my .vimrc file?

You need to create it. In most installations I've used it hasn't been created by default.

You usually create it as ~/.vimrc.

Jackson enum Serializing and DeSerializer

You can customize the deserialization for any attribute.

Declare your deserialize class using the annotationJsonDeserialize (import com.fasterxml.jackson.databind.annotation.JsonDeserialize) for the attribute that will be processed. If this is an Enum:

@JsonDeserialize(using = MyEnumDeserialize.class)
private MyEnum myEnum;

This way your class will be used to deserialize the attribute. This is a full example:

public class MyEnumDeserialize extends JsonDeserializer<MyEnum> {

    @Override
    public MyEnum deserialize(JsonParser jsonParser, DeserializationContext deserializationContext) throws IOException {
        JsonNode node = jsonParser.getCodec().readTree(jsonParser);
        MyEnum type = null;
        try{
            if(node.get("attr") != null){
                type = MyEnum.get(Long.parseLong(node.get("attr").asText()));
                if (type != null) {
                    return type;
                }
            }
        }catch(Exception e){
            type = null;
        }
        return type;
    }
}

How to print binary tree diagram?

michal.kreuzman nice one I will have to say. It was useful.

However, the above works only for single digits: if you are going to use more than one digit, the structure is going to get misplaced since you are using spaces and not tabs.

As for my later codes I needed more digits than only 2, so I made a program myself.

It has some bugs now, again right now I am feeling lazy to correct them but it prints very beautifully and the nodes can take a larger number of digits.

The tree is not going to be as the question mentions but it is 270 degrees rotated :)

public static void printBinaryTree(TreeNode root, int level){
    if(root==null)
         return;
    printBinaryTree(root.right, level+1);
    if(level!=0){
        for(int i=0;i<level-1;i++)
            System.out.print("|\t");
        System.out.println("|-------"+root.val);
    }
    else
        System.out.println(root.val);
    printBinaryTree(root.left, level+1);
}    

Place this function with your own specified TreeNode and keep the level initially 0, and enjoy!

Here are some of the sample outputs:

|       |       |-------11
|       |-------10
|       |       |-------9
|-------8
|       |       |-------7
|       |-------6
|       |       |-------5
4
|       |-------3
|-------2
|       |-------1


|       |       |       |-------10
|       |       |-------9
|       |-------8
|       |       |-------7
|-------6
|       |-------5
4
|       |-------3
|-------2
|       |-------1

Only problem is with the extending branches; I will try to solve the problem as soon as possible but till then you can use it too.

must appear in the GROUP BY clause or be used in an aggregate function

I recently run into this problem, when trying to count using case when, and found that changing the order of the which and count statements fixes the problem:

SELECT date(dateday) as pick_day,
COUNT(CASE WHEN (apples = 'TRUE' OR oranges 'TRUE') THEN fruit END)  AS fruit_counter

FROM pickings

GROUP BY 1

Instead of using - in the latter, where I got errors that apples and oranges should appear in aggregate functions

CASE WHEN ((apples = 'TRUE' OR oranges 'TRUE') THEN COUNT(*) END) END AS fruit_counter

javascript date to string

Maybe it is easier to convert the Date into the actual integer 20110506105524 and then convert this into a string:

function printDate() {
    var temp = new Date();
    var dateInt =
        ((((temp.getFullYear() * 100 + 
            temp.getMonth() + 1) * 100 + 
           temp.getDate()) * 100 +
          temp.getHours()) * 100 + 
         temp.getMinutes()) * 100 + 
        temp.getSeconds();

    debug ( '' + dateInt );  // convert to String
}

When temp.getFullYear() < 1000 the result will be one (or more) digits shorter.

Caution: this wont work with millisecond precision (i.e. 17 digits) since Number.MAX_SAFE_INTEGER is 9007199254740991 which is only 16 digits.

How do I fix a Git detached head?

Being in "detached head" means that HEAD refers to a specific unnamed commit (as opposite to a named branch) (cf: https://git-scm.com/docs/git-checkout section Detached head)

To fix the problem, you only need to select the branch that was selected before by

git checkout @{-1}

How to get data from Magento System Configuration

Magento 1.x

(magento 2 example provided below)

sectionName, groupName and fieldName are present in etc/system.xml file of the module.

PHP Syntax:

Mage::getStoreConfig('sectionName/groupName/fieldName');

From within an editor in the admin, such as the content of a CMS Page or Static Block; the description/short description of a Catalog Category, Catalog Product, etc.

{{config path="sectionName/groupName/fieldName"}}

For the "Within an editor" approach to work, the field value must be passed through a filter for the {{ ... }} contents to be parsed out. Out of the box, Magento will do this for Category and Product descriptions, as well as CMS Pages and Static Blocks. However, if you are outputting the content within your own custom view script and want these variables to be parsed out, you can do so like this:

<?php
    $example = Mage::getModel('identifier/name')->load(1);
    $filter  = Mage::getModel('cms/template_filter');
    echo $filter->filter($example->getData('field'));
?>

Replacing identifier/name with the a appropriate values for the model you are loading, and field with the name of the attribute you want to output, which may contain {{ ... }} occurrences that need to be parsed out.

Magento 2.x

From any Block class that extends \Magento\Framework\View\Element\AbstractBlock

$this->_scopeConfig->getValue('sectionName/groupName/fieldName');

Any other PHP class:

If the class (and none of it's parent's) does not inject \Magento\Framework\App\Config\ScopeConfigInterface via the constructor, you'll have to add it to your class.

// ... Remaining class definition above...

/**
 * @var \Magento\Framework\App\Config\ScopeConfigInterface
 */
protected $_scopeConfig;

/**
 * Constructor
 */
public function __construct(
    \Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig
    // ...any other injected classes the class depends on...
) {
  $this->_scopeConfig = $scopeConfig;
  // Remaining constructor logic...
}

// ...remaining class definition below...

Once you have injected it into your class, you can now fetch store configuration values with the same syntax example given above for block classes.

Note that after modifying any class's __construct() parameter list, you may have to clear your generated classes as well as dependency injection directory: var/generation & var/di

grabbing first row in a mysql query only

You didn't specify how the order is determined, but this will give you a rank value in MySQL:

SELECT t.*,
       @rownum := @rownum +1 AS rank
  FROM TBL_FOO t
  JOIN (SELECT @rownum := 0) r
 WHERE t.name = 'sarmen'

Then you can pick out what rows you want, based on the rank value.

How to use hex color values

public static func hexStringToUIColor (hex:String) -> UIColor {
    var cString:String = hex.trimmingCharacters(in: .whitespacesAndNewlines).uppercased()

    if (cString.hasPrefix("#")) {
        cString.remove(at: cString.startIndex)
    }

    if ((cString.characters.count) == 6) {

        var rgbValue:UInt32 = 0
        Scanner(string: cString).scanHexInt32(&rgbValue)

        return UIColor(
            red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0,
            green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0,
            blue: CGFloat(rgbValue & 0x0000FF) / 255.0,
            alpha: CGFloat(1.0)
        )
    }else if ((cString.characters.count) == 8) {

        var rgbValue:UInt32 = 0
        Scanner(string: cString).scanHexInt32(&rgbValue)

        return UIColor(
            red: CGFloat((rgbValue & 0x00FF0000) >> 16) / 255.0,
            green: CGFloat((rgbValue & 0x0000FF00) >> 8) / 255.0,
            blue: CGFloat(rgbValue & 0x000000FF) / 255.0,
            alpha: CGFloat((rgbValue & 0xFF000000) >> 24) / 255.0
        )
    }else{
        return UIColor.gray
    }
}

How to use

var color: UIColor = hexStringToUIColor(hex: "#00ff00"); // Without transparency
var colorWithTransparency: UIColor = hexStringToUIColor(hex: "#dd00ff00"); // With transparency

Convert form data to JavaScript object with jQuery

I found a problem with Tobias Cohen's code (I don't have enough points to comment on it directly), which otherwise works for me. If you have two select options with the same name, both with value="", the original code will produce "name":"" instead of "name":["",""]

I think this can fixed by adding " || o[this.name] == ''" to the first if condition:

$.fn.serializeObject = function()
{
    var o = {};
    var a = this.serializeArray();
    $.each(a, function() {
        if (o[this.name] || o[this.name] == '') {
            if (!o[this.name].push) {
                o[this.name] = [o[this.name]];
            }
            o[this.name].push(this.value || '');
        } else {
            o[this.name] = this.value || '';
        }
    });
    return o;
};

How to install and use "make" in Windows?

The accepted answer is a bad idea in general because the manually created make.exe will stick around and can potentially cause unexpected problems. It actually breaks RubyInstaller: https://github.com/oneclick/rubyinstaller2/issues/105

An alternative is installing make via Chocolatey (as pointed out by @Vasantha Ganesh K)

Another alternative is installing MSYS2 from Chocolatey and using make from C:\tools\msys64\usr\bin. If make isn't installed automatically with MSYS2 you need to install it manually via pacman -S make (as pointed out by @Thad Guidry and @Luke).

Load a Bootstrap popover content with AJAX. Is this possible?

I think my solution is more simple with default functionality.

http://jsfiddle.net/salt/wbpb0zoy/1/

_x000D_
_x000D_
$("a.popover-ajax").each(function(){_x000D_
   $(this).popover({_x000D_
   trigger:"focus",_x000D_
   placement: function (context, source) {_x000D_
                  var obj = $(source);_x000D_
      $.get(obj.data("url"),function(d) {_x000D_
                        $(context).html( d.titles[0].title)_x000D_
                  }); _x000D_
   },_x000D_
   html:true,_x000D_
   content:"loading"_x000D_
   });_x000D_
});
_x000D_
<link href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.6/css/bootstrap.min.css" rel="stylesheet"/>_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.6/js/bootstrap.min.js"></script>_x000D_
_x000D_
_x000D_
<ul class="list-group">_x000D_
  <li class="list-group-item"><a href="#" data-url="https://tr.instela.com/api/v2/list?op=today" class="popover-ajax">Cras justo odio</a></li>_x000D_
  <li class="list-group-item"><a href="#" data-url="https://tr.instela.com/api/v2/list?op=today" class="popover-ajax">Dapibus ac facilisis in</a></li>_x000D_
  <li class="list-group-item"><a href="#" data-url="https://tr.instela.com/api/v2/list?op=today" class="popover-ajax">Morbi leo risus</a></li>_x000D_
  <li class="list-group-item"><a href="#" data-url="https://tr.instela.com/api/v2/list?op=today" class="popover-ajax">Porta ac consectetur ac</a></li>_x000D_
  <li class="list-group-item"><a href="#" data-url="https://tr.instela.com/api/v2/list?op=today" class="popover-ajax">Vestibulum at eros</a></li>_x000D_
</ul>
_x000D_
_x000D_
_x000D_

What's the regular expression that matches a square bracket?

How about using backslash \ in front of the square bracket. Normally square brackets match a character class.

Ifelse statement in R with multiple conditions

another solution using dplyr is:

df <- ## your data ##
df <- df %>%
        mutate(Den = ifelse(any(is.na(Den)) | any(Den != 1), 0, 1))

How to determine if one array contains all elements of another array

Most answers based on (a1 - a2) or (a1 & a2) would not work if there are duplicate elements in either array. I arrived here looking for a way to see if all letters of a word (split to an array) were part of a set of letters (for scrabble for example). None of these answers worked, but this one does:

def contains_all?(a1, a2)
  try = a1.chars.all? do |letter|
    a1.count(letter) <= a2.count(letter)
  end
  return try
end

ARG or ENV, which one to use in this case?

From Dockerfile reference:

  • The ARG instruction defines a variable that users can pass at build-time to the builder with the docker build command using the --build-arg <varname>=<value> flag.

  • The ENV instruction sets the environment variable <key> to the value <value>.
    The environment variables set using ENV will persist when a container is run from the resulting image.

So if you need build-time customization, ARG is your best choice.
If you need run-time customization (to run the same image with different settings), ENV is well-suited.

If I want to add let's say 20 (a random number) of extensions or any other feature that can be enable|disable

Given the number of combinations involved, using ENV to set those features at runtime is best here.

But you can combine both by:

  • building an image with a specific ARG
  • using that ARG as an ENV

That is, with a Dockerfile including:

ARG var
ENV var=${var}

You can then either build an image with a specific var value at build-time (docker build --build-arg var=xxx), or run a container with a specific runtime value (docker run -e var=yyy)

How can I remove the extension of a filename in a shell script?

Using POSIX's built-in only:

#!/usr/bin/env sh
path=this.path/with.dots/in.path.name/filename.tar.gz

# Get the basedir without external command
# by stripping out shortest trailing match of / followed by anything
dirname=${path%/*}

# Get the basename without external command
# by stripping out longest leading match of anything followed by /
basename=${path##*/}

# Strip uptmost trailing extension only
# by stripping out shortest trailing match of dot followed by anything
oneextless=${basename%.*}; echo "$noext" 

# Strip all extensions
# by stripping out longest trailing match of dot followed by anything
noext=${basename%%.*}; echo "$noext"

# Printout demo
printf %s\\n "$path" "$dirname" "$basename" "$oneextless" "$noext"

Printout demo:

this.path/with.dots/in.path.name/filename.tar.gz
this.path/with.dots/in.path.name
filename.tar.gz
filename.tar
filename

API pagination best practices

Pagination is generally a "user" operation and to prevent overload both on computers and the human brain you generally give a subset. However, rather than thinking that we don't get the whole list it may be better to ask does it matter?

If an accurate live scrolling view is needed, REST APIs which are request/response in nature are not well suited for this purpose. For this you should consider WebSockets or HTML5 Server-Sent Events to let your front end know when dealing with changes.

Now if there's a need to get a snapshot of the data, I would just provide an API call that provides all the data in one request with no pagination. Mind you, you would need something that would do streaming of the output without temporarily loading it in memory if you have a large data set.

For my case I implicitly designate some API calls to allow getting the whole information (primarily reference table data). You can also secure these APIs so it won't harm your system.

How to execute a Ruby script in Terminal?

To call ruby file use : ruby your_program.rb

To execute your ruby file as script:

  1. start your program with #!/usr/bin/env ruby

  2. run that script using ./your_program.rb param

  3. If you are not able to execute this script check permissions for file.

How to force a SQL Server 2008 database to go Offline

Go offline

USE master
GO
ALTER DATABASE YourDatabaseName
SET OFFLINE WITH ROLLBACK IMMEDIATE
GO

Go online

USE master
GO
ALTER DATABASE YourDatabaseName
SET ONLINE
GO

How do I find the data directory for a SQL Server instance?

As of Sql Server 2012, you can use the following query:

SELECT SERVERPROPERTY('INSTANCEDEFAULTDATAPATH') as [Default_data_path], SERVERPROPERTY('INSTANCEDEFAULTLOGPATH') as [Default_log_path];

(This was taken from a comment at http://technet.microsoft.com/en-us/library/ms174396.aspx, and tested.)

How to exclude rows that don't join with another table?

use a "not exists" left join:

SELECT p.*
FROM primary_table p LEFT JOIN second s ON p.ID = s.ID
WHERE s.ID IS NULL

How to keep keys/values in same order as declared?

You can't really do what you want with a dictionary. You already have the dictionary d = {'ac':33, 'gw':20, 'ap':102, 'za':321, 'bs':10}created. I found there was no way to keep in order once it is already created. What I did was make a json file instead with the object:

{"ac":33,"gw":20,"ap":102,"za":321,"bs":10}

I used:

r = json.load(open('file.json'), object_pairs_hook=OrderedDict)

then used:

print json.dumps(r)

to verify.

How to convert a string to JSON object in PHP

Try with json_encode().

And look again Valid JSON

QR Code encoding and decoding using zxing

For what it's worth, my groovy spike seems to work with both UTF-8 and ISO-8859-1 character encodings. Not sure what will happen when a non zxing decoder tries to decode the UTF-8 encoded image though... probably varies depending on the device.

// ------------------------------------------------------------------------------------
// Requires: groovy-1.7.6, jdk1.6.0_03, ./lib with zxing core-1.7.jar, javase-1.7.jar 
// Javadocs: http://zxing.org/w/docs/javadoc/overview-summary.html
// Run with: groovy -cp "./lib/*" zxing.groovy
// ------------------------------------------------------------------------------------

import com.google.zxing.*
import com.google.zxing.common.*
import com.google.zxing.client.j2se.*

import java.awt.image.BufferedImage
import javax.imageio.ImageIO

def class zxing {
    def static main(def args) {
        def filename = "./qrcode.png"
        def data = "This is a test to see if I can encode and decode this data..."
        def charset = "UTF-8" //"ISO-8859-1" 
        def hints = new Hashtable<EncodeHintType, String>([(EncodeHintType.CHARACTER_SET): charset])

        writeQrCode(filename, data, charset, hints, 100, 100)

        assert data == readQrCode(filename, charset, hints)
    }

    def static writeQrCode(def filename, def data, def charset, def hints, def width, def height) {
        BitMatrix matrix = new MultiFormatWriter().encode(new String(data.getBytes(charset), charset), BarcodeFormat.QR_CODE, width, height, hints)
        MatrixToImageWriter.writeToFile(matrix, filename.substring(filename.lastIndexOf('.')+1), new File(filename))
    }

    def static readQrCode(def filename, def charset, def hints) {
        BinaryBitmap binaryBitmap = new BinaryBitmap(new HybridBinarizer(new BufferedImageLuminanceSource(ImageIO.read(new FileInputStream(filename)))))
        Result result = new MultiFormatReader().decode(binaryBitmap, hints)

        result.getText()        
    }

}

Check for column name in a SqlDataReader object

Here is a working sample for Jasmin's idea:

var cols = r.GetSchemaTable().Rows.Cast<DataRow>().Select
    (row => row["ColumnName"] as string).ToList(); 

if (cols.Contains("the column name"))
{

}

Key Presses in Python

import keyboard

keyboard.press_and_release('anykey')

what does mysql_real_escape_string() really do?

Best explained here.

http://www.w3schools.com/php/func_mysql_real_escape_string.asp

http://www.tizag.com/mysqlTutorial/mysql-php-sql-injection.php

It generally it helps to avoid SQL injection, for example consider the following code:

<?php
// Query database to check if there are any matching users
$query = "SELECT * FROM users WHERE user='{$_POST['username']}' AND password='{$_POST['password']}'";
mysql_query($query);

// We didn't check $_POST['password'], it could be anything the user wanted! For example:
$_POST['username'] = 'aidan';
$_POST['password'] = "' OR ''='";

// This means the query sent to MySQL would be:
echo $query;
?>

and a hacker can send a query like:

SELECT * FROM users WHERE user='aidan' AND password='' OR ''=''

This would allow anyone to log in without a valid password.

How do you log content of a JSON object in Node.js?

console.dir() is the most direct way.

Formatting code in Notepad++

ANSWER AS OF June 2019

Install the XML Tools plugin from the Plugin Admin (in Notepad++ 7.7 at least)

Then click Plugins -> XML Tools -> Pretty Print (XML Only with Line breaks)

That did it for me.

JavaScript ternary operator example with functions

There is nothing particularly tricky about the example you posted.

In a ternary operator, the first argument (the conditional) is evaluated and if the result is true, the second argument is evaluated and returned, otherwise, the third is evaluated and returned. Each of those arguments can be any valid code block, including function calls.

Think of it this way:

var x = (1 < 2) ? true : false;

Could also be written as:

var x = (1 < 2) ? getTrueValue() : getFalseValue();

This is perfectly valid, and those functions can contain any arbitrary code, whether it is related to returning a value or not. Additionally, the results of the ternary operation don't have to be assigned to anything, just as function results do not have to be assigned to anything:

(1 < 2) ? getTrueValue() : getFalseValue();

Now simply replace those with any arbitrary functions, and you are left with something like your example:

(1 < 2) ? removeItem($this) : addItem($this);

Now your last example really doesn't need a ternary at all, as it can be written like this:

x = (1 < 2);  // x will be set to "true"

How to get the selected value from RadioButtonList?

radiobuttonlist.selected <value> to process with your code.

Is it possible to use "return" in stored procedure?

-- IN arguments : you get them. You can modify them locally but caller won't see it
-- IN OUT arguments: initialized by caller, already have a value, you can modify them and the caller will see it
-- OUT arguments: they're reinitialized by the procedure, the caller will see the final value.
CREATE PROCEDURE f (p IN NUMBER, x IN OUT NUMBER, y OUT NUMBER)
IS
BEGIN
   x:=x * p;
   y:=4 * p;
END;
/

SET SERVEROUTPUT ON

declare
   foo number := 30;
   bar number := 0;
begin
   f(5,foo,bar);
   dbms_output.put_line(foo || ' ' || bar);
end;
/

-- Procedure output can be collected from variables x and y (ans1:= x and ans2:=y) will be: 150 and 20 respectively.

-- Answer borrowed from: https://stackoverflow.com/a/9484228/1661078

How to pass an object into a state using UI-router?

1)

$stateProvider
        .state('app.example1', {
                url: '/example',
                views: {
                    'menuContent': {
                        templateUrl: 'templates/example.html',
                        controller: 'ExampleCtrl'
                    }
                }
            })
            .state('app.example2', {
                url: '/example2/:object',
                views: {
                    'menuContent': {
                        templateUrl: 'templates/example2.html',
                        controller: 'Example2Ctrl'
                    }
                }
            })

2)

.controller('ExampleCtrl', function ($state, $scope, UserService) {


        $scope.goExample2 = function (obj) {

            $state.go("app.example2", {object: JSON.stringify(obj)});
        }

    })
    .controller('Example2Ctrl', function ($state, $scope, $stateParams) {

        console.log(JSON.parse($state.params.object));


    })

optional parameters in SQL Server stored proc?

Yes, it is. Declare parameter as so:

@Sort varchar(50) = NULL

Now you don't even have to pass the parameter in. It will default to NULL (or whatever you choose to default to).

Session state can only be used when enableSessionState is set to true either in a configuration

For SharePoint Can find the web config file in C:\inetpub\wwwroot\wss\VirtualDirectories\Sitecollection port number - and Make changes

 <system.web>
  <pages enableSessionState="true" /> 
 </system.web>

and using SharePoint Management Shell Run below Command

   Enable-SPSessionStateService -DefaultProvision

How do I serialize a C# anonymous type to a JSON string?

You can try my ServiceStack JsonSerializer it's the fastest .NET JSON serializer at the moment. It supports serializing DataContract's, Any POCO Type, Interfaces, Late-bound objects including anonymous types, etc.

Basic Example

var customer = new Customer { Name="Joe Bloggs", Age=31 };
var json = customer.ToJson();
var fromJson = json.FromJson<Customer>(); 

Note: Only use Microsofts JavaScriptSerializer if performance is not important to you as I've had to leave it out of my benchmarks since its up to 40x-100x slower than the other JSON serializers.

Socket.io + Node.js Cross-Origin Request Blocked

For anyone looking here for new Socket.io (3.x) the migration documents are fairly helpful.

In particular this snippet:

const io = require("socket.io")(httpServer, {
  cors: {
    origin: "https://example.com",
    methods: ["GET", "POST"],
    allowedHeaders: ["my-custom-header"],
    credentials: true
  }
});

JavaScript: Is there a way to get Chrome to break on all errors?

Edit: The original link I answered with is now invalid.The newer URL would be https://developers.google.com/web/tools/chrome-devtools/javascript/add-breakpoints#exceptions as of 2016-11-11.

I realize this question has an answer, but it's no longer accurate. Use the link above ^


(link replaced by edited above) - you can now set it to break on all exceptions or just unhandled ones. (Note that you need to be in the Sources tab to see the button.)

Chrome's also added some other really useful breakpoint capabilities now, such as breaking on DOM changes or network events.

Normally I wouldn't re-answer a question, but I had the same question myself, and I found this now-wrong answer, so I figured I'd put this information in here for people who came along later in searching. :)

How to retrieve JSON Data Array from ExtJS Store

A better (IMO) one-line approach, works on ExtJS 4, not sure about 3:

store.proxy.reader.jsonData

Finding all the subsets of a set

Here is a simple recursive algorithm in python for finding all subsets of a set:

def find_subsets(so_far, rest):
        print 'parameters', so_far, rest
        if not rest:
            print so_far
        else:
            find_subsets(so_far + [rest[0]], rest[1:])
            find_subsets(so_far, rest[1:])


find_subsets([], [1,2,3])

The output will be the following: $python subsets.py

parameters [] [1, 2, 3]
parameters [1] [2, 3]
parameters [1, 2] [3]
parameters [1, 2, 3] []
[1, 2, 3]
parameters [1, 2] []
[1, 2]
parameters [1] [3]
parameters [1, 3] []
[1, 3]
parameters [1] []
[1]
parameters [] [2, 3]
parameters [2] [3]
parameters [2, 3] []
[2, 3]
parameters [2] []
[2]
parameters [] [3]
parameters [3] []
[3]
parameters [] []
[]

Watch the following video from Stanford for a nice explanation of this algorithm:

https://www.youtube.com/watch?v=NdF1QDTRkck&feature=PlayList&p=FE6E58F856038C69&index=9

Get first element of Series without knowing the index

Use iloc to access by position (rather than label):

In [11]: df = pd.DataFrame([[1, 2], [3, 4]], ['a', 'b'], ['A', 'B'])

In [12]: df
Out[12]: 
   A  B
a  1  2
b  3  4

In [13]: df.iloc[0]  # first row in a DataFrame
Out[13]: 
A    1
B    2
Name: a, dtype: int64

In [14]: df['A'].iloc[0]  # first item in a Series (Column)
Out[14]: 1

Copy a table from one database to another in Postgres

You could do the following:

pg_dump -h <host ip address> -U <host db user name> -t <host table> > <host database> | psql -h localhost -d <local database> -U <local db user>

NOT IN vs NOT EXISTS

Actually, I believe this would be the fastest:

SELECT ProductID, ProductName 
    FROM Northwind..Products p  
          outer join Northwind..[Order Details] od on p.ProductId = od.ProductId)
WHERE od.ProductId is null

Get the list of stored procedures created and / or modified on a particular date?

SELECT name
FROM sys.objects
WHERE type = 'P'
AND (DATEDIFF(D,modify_date, GETDATE()) < 7
     OR DATEDIFF(D,create_date, GETDATE()) < 7)

Ignore <br> with CSS?

You can use span elements instead of the br if you want the white space method to work, as it depends on pseudo-elements which are "not defined" for replaced elements.

HTML

<p>
   To break lines<span class="line-break">in a paragraph,</span><span>don't use</span><span>the 'br' element.</span>
</p>

CSS

span {white-space: pre;}

span:after {content: ' ';}

span.line-break {display: block;}

span.line-break:after {content: none;}

DEMO

The line break is simply achieved by setting the appropriate span element to display:block.

By using IDs and/ or Classes in your HTML markup you can easily target every single or combination of span elements by CSS or use CSS selectors like nth-child().

So you can e.g. define different break points by using media queries for a responsive layout.

And you can also simply add/ remove/ toggle classes by Javascript (jQuery).

The "advantage" of this method is its robustness - works in every browser that supports pseudo-elements (see: Can I use - CSS Generated content).

As an alternative it is also possible to add a line break via pseudo-elements:

span.break:before {  
    content: "\A";
    white-space: pre;
}

DEMO

Java: how can I split an ArrayList in multiple small ArrayLists?

Just to be clear, This still have to be tested more...

public class Splitter {

public static <T> List<List<T>> splitList(List<T> listTobeSplit, int size) {
    List<List<T>> sublists= new LinkedList<>();
    if(listTobeSplit.size()>size) {
    int counter=0;
    boolean lastListadded=false;

    List<T> subList=new LinkedList<>();

    for(T t: listTobeSplit) {           
         if (counter==0) {               
             subList =new LinkedList<>();
             subList.add(t);
             counter++;
             lastListadded=false;
         }
         else if(counter>0 && counter<size-1) {
             subList.add(t);
             counter++;
         }
         else {
             lastListadded=true;
             subList.add(t);
             sublists.add(subList);
             counter=0;
         }              
    }
    if(lastListadded==false)
        sublists.add(subList);      
    }
    else {
        sublists.add(listTobeSplit);
    }
    log.debug("sublists: "+sublists);
    return sublists;
 }
}

SSH Key - Still asking for password and passphrase

Use ssh-add command to add your public key to the ssh-agent.

ssh-add

Make sure the ssh public key e.g. ~/.ssh/id_rsa.pub is what you have in your repo settings.

Make sure you can actually ssh into the server e.g. For Bitbucket:

ssh -T [email protected]

Update the url to move from https to ssh. You can check which you use by checking the output of:

git remote -v

If you see a https:// in the urls, then you are still using https. To update it: Take the url and just replace https:// with ssh:// e.g. Change:

https://[email protected]/../..

To:

ssh://[email protected]/../..

Referenced: https://docs.github.com/en/github/using-git/changing-a-remotes-url#switching-remote-urls-from-https-to-ssh

What is the meaning of {...this.props} in Reactjs

It is ES-6 feature. It means you extract all the properties of props in div.{... }

operator is used to extract properties of an object.

How to find all trigger associated with a table with SQL Server?

select t.name as TriggerName,m.definition,is_disabled 
from sys.all_sql_modules m 
inner join  
sys.triggers t
on m.object_id = t.object_id 
inner join sys.objects o
on o.object_id = t.parent_id
Where o.name = 'YourTableName'

This will give you all triggers on a Specified Table

Batch file script to zip files

for /d %%a in (*) do (ECHO zip -r -p "%%~na.zip" ".\%%a\*")

should work from within a batch.

Note that I've included an ECHO to simply SHOW the command that is proposed. You'd need to remove the ECHO keywor to EXECUTE the commands.

How many concurrent AJAX (XmlHttpRequest) requests are allowed in popular browsers?

The network results at Browserscope will give you both Connections per Hostname and Max Connections for popular browsers. The data is gathered by running tests on users "in the wild," so it will stay up to date.

Undo git pull, how to bring repos to old state

If there is a failed merge, which is the most common reason for wanting to undo a git pull, running git reset --merge does exactly what one would expect: keep the fetched files, but undo the merge that git pull attempted to merge. Then one can decide what to do without the clutter that git merge sometimes generates. And it does not need one to find the exact commit ID which --hard mentioned in every other answer requires.

Why doesn't logcat show anything in my Android?

If you are using a device, the simplest check is to restart eclipse.

** you don't have to shutdown eclipse **

use File > Restart

in a quick second or two you should see your LogCat return

How to split a single column values to multiple column values?

I used it recently:

select 
substring(name,1,charindex(' ',name)-1) as Col1,
substring(name,charindex(' ',name)+1,len(name)) as Col2 
from TableName

How to add `style=display:"block"` to an element using jQuery?

$("#YourElementID").css("display","block");

Edit: or as dave thieben points out in his comment below, you can do this as well:

$("#YourElementID").css({ display: "block" });

Oracle ORA-12154: TNS: Could not resolve service name Error?

I fixed this problem using this steps.

First of all, this error occured , if you didn't install same directory or drive.

But the answer is here.

  1. Login windows as a Adminstrator.
  2. Go to Control Panel.
  3. System Properties and click Enviroment
  4. Find the OS variable and change name as a "TNS_ADMIN"

    enter image description here

  5. And change the value as a "tnsnames's directory address" enter image description here

  6. Restart the system.

  7. Congrulations.

jQuery append() vs appendChild()

appendChild is a DOM vanilla-js function.

append is a jQuery function.

They each have their own quirks.

Connect to Amazon EC2 file directory using Filezilla and SFTP

You can use any FTP client. I use winscp and it works just fine. In all these clients; you can specify the ssh secure key.

How to output in CLI during execution of PHP Unit tests?

It is possible to use Symfony\Component\Console\Output\TrimmedBufferOutput and then test the buffered output string like this:

use Symfony\Component\Console\Output\TrimmedBufferOutput;

//...
public function testSomething()
{
   $output = new TrimmedBufferOutput(999);
   $output->writeln('Do something in your code with the output class...');
   
   //test the output:
   $this->assertStringContainsString('expected string...', $output->fetch());   
}

how to parse a "dd/mm/yyyy" or "dd-mm-yyyy" or "dd-mmm-yyyy" formatted date string using JavaScript or jQuery

Try this:

 function GetDateFormat(controlName) {
        if ($('#' + controlName).val() != "") {      
            var d1 = Date.parse($('#' + controlName).val().toString().replace(/([0-9]+)\/([0-9]+)/,'$2/$1'));
            if (d1 == null) {
                alert('Date Invalid.');
                $('#' + controlName).val("");
            }
                var array = d1.toString('dd-MMM-yyyy');
                $('#' + controlName).val(array);
        }
    }

The RegExp replace .replace(/([0-9]+)\/([0-9]+)/,'$2/$1') change day/month position.

Regex: match word that ends with "Id"

Try this regular expression:

\w*Id\b

\w* allows word characters in front of Id and the \b ensures that Id is at the end of the word (\b is word boundary assertion).

convert json ipython notebook(.ipynb) to .py file

Jupytext allows for such a conversion on the command line, and importantly you can go back again from the script to a notebook (even an executed notebook). See here.

Replace NA with 0 in a data frame column

First, here's some sample data:

set.seed(1)
dat <- data.frame(one = rnorm(15),
                 two = sample(LETTERS, 15),
                 three = rnorm(15),
                 four = runif(15))
dat <- data.frame(lapply(dat, function(x) { x[sample(15, 5)] <- NA; x }))
head(dat)
#          one  two       three      four
# 1         NA    M  0.80418951 0.8921983
# 2  0.1836433    O -0.05710677        NA
# 3 -0.8356286    L  0.50360797 0.3899895
# 4         NA    E          NA        NA
# 5  0.3295078    S          NA 0.9606180
# 6 -0.8204684 <NA> -1.28459935 0.4346595

Here's our replacement:

dat[["four"]][is.na(dat[["four"]])] <- 0
head(dat)
#          one  two       three      four
# 1         NA    M  0.80418951 0.8921983
# 2  0.1836433    O -0.05710677 0.0000000
# 3 -0.8356286    L  0.50360797 0.3899895
# 4         NA    E          NA 0.0000000
# 5  0.3295078    S          NA 0.9606180
# 6 -0.8204684 <NA> -1.28459935 0.4346595

Alternatively, you can, of course, write dat$four[is.na(dat$four)] <- 0

Dynamic instantiation from string name of a class in dynamically imported module?

Copy-paste snippet:

import importlib
def str_to_class(module_name, class_name):
    """Return a class instance from a string reference"""
    try:
        module_ = importlib.import_module(module_name)
        try:
            class_ = getattr(module_, class_name)()
        except AttributeError:
            logging.error('Class does not exist')
    except ImportError:
        logging.error('Module does not exist')
    return class_ or None

How to read xml file contents in jQuery and display in html elements?

Simply you can read XML file as dataType: "xml", it will retuen xml object already parsed. you can use it as jquery object and find anything or loop throw it…etc.

$(document).ready(function(){
   $.ajax({
    type: "GET" ,
    url: "sampleXML.xml" ,
    dataType: "xml" ,
    success: function(xml) {

    //var xmlDoc = $.parseXML( xml );   <------------------this line
    //if single item
    var person = $(xml).find('person').text();  

    //but if it's multible items then loop
    $(xml).find('person').each(function(){
     $("#temp").append('<li>' + $(this).text() + '</li>');  
    }); 
    }       
});
});

jQuery docs for parseXML

How to solve javax.net.ssl.SSLHandshakeException Error?

First, you need to obtain the public certificate from the server you're trying to connect to. That can be done in a variety of ways, such as contacting the server admin and asking for it, using OpenSSL to download it, or, since this appears to be an HTTP server, connecting to it with any browser, viewing the page's security info, and saving a copy of the certificate. (Google should be able to tell you exactly what to do for your specific browser.)

Now that you have the certificate saved in a file, you need to add it to your JVM's trust store. At $JAVA_HOME/jre/lib/security/ for JREs or $JAVA_HOME/lib/security for JDKs, there's a file named cacerts, which comes with Java and contains the public certificates of the well-known Certifying Authorities. To import the new cert, run keytool as a user who has permission to write to cacerts:

keytool -import -file <the cert file> -alias <some meaningful name> -keystore <path to cacerts file>

It will most likely ask you for a password. The default password as shipped with Java is changeit. Almost nobody changes it. After you complete these relatively simple steps, you'll be communicating securely and with the assurance that you're talking to the right server and only the right server (as long as they don't lose their private key).

In Angular, What is 'pathmatch: full' and what effect does it have?

RouterModule.forRoot([
      { path: 'welcome', component: WelcomeComponent },
      { path: '', redirectTo: 'welcome', pathMatch: 'full' },
      { path: '**', component: 'pageNotFoundComponent' }
    ])

Case 1 pathMatch:'full': In this case, when app is launched on localhost:4200 (or some server) the default page will be welcome screen, since the url will be https://localhost:4200/

If https://localhost:4200/gibberish this will redirect to pageNotFound screen because of path:'**' wildcard

Case 2 pathMatch:'prefix':

If the routes have { path: '', redirectTo: 'welcome', pathMatch: 'prefix' }, now this will never reach the wildcard route since every url would match path:'' defined.

Print ArrayList

This is a simple code of add the value in ArrayList and print the ArrayList Value

public class Samim {

public static void main(String args[]) {
    // Declare list
    List<String> list = new ArrayList<>();

    // Add value in list
    list.add("First Value ArrayPosition=0");
    list.add("Second Value ArrayPosition=1");
    list.add("Third Value ArrayPosition=2");
    list.add("Fourth Value ArrayPosition=3");
    list.add("Fifth Value ArrayPosition=4");
    list.add("Sixth Value ArrayPosition=5");
    list.add("Seventh Value ArrayPosition=6");

    String[] objects1 = list.toArray(new String[0]);

    // Print Position Value
    System.err.println(objects1[2]);

    // Print All Value
    for (String val : objects1) {
        System.out.println(val);
      }
    }
}

Unrecognized escape sequence for path string containing backslashes

Try this:

string foo = @"D:\Projects\Some\Kind\Of\Pathproblem\wuhoo.xml";

The problem is that in a string, a \ is an escape character. By using the @ sign you tell the compiler to ignore the escape characters.

You can also get by with escaping the \:

string foo = "D:\\Projects\\Some\\Kind\\Of\\Pathproblem\\wuhoo.xml";

How to deal with SettingWithCopyWarning in Pandas

In general the point of the SettingWithCopyWarning is to show users (and especially new users) that they may be operating on a copy and not the original as they think. There are false positives (IOW if you know what you are doing it could be ok). One possibility is simply to turn off the (by default warn) warning as @Garrett suggest.

Here is another option:

In [1]: df = DataFrame(np.random.randn(5, 2), columns=list('AB'))

In [2]: dfa = df.ix[:, [1, 0]]

In [3]: dfa.is_copy
Out[3]: True

In [4]: dfa['A'] /= 2
/usr/local/bin/ipython:1: SettingWithCopyWarning: A value is trying to be set on a copy of a slice from a DataFrame.
Try using .loc[row_index,col_indexer] = value instead
  #!/usr/local/bin/python

You can set the is_copy flag to False, which will effectively turn off the check, for that object:

In [5]: dfa.is_copy = False

In [6]: dfa['A'] /= 2

If you explicitly copy then no further warning will happen:

In [7]: dfa = df.ix[:, [1, 0]].copy()

In [8]: dfa['A'] /= 2

The code the OP is showing above, while legitimate, and probably something I do as well, is technically a case for this warning, and not a false positive. Another way to not have the warning would be to do the selection operation via reindex, e.g.

quote_df = quote_df.reindex(columns=['STK', ...])

Or,

quote_df = quote_df.reindex(['STK', ...], axis=1)  # v.0.21

What's the best way to get the current URL in Spring MVC?

Java's URI Class can help you out of this:

public static String getCurrentUrl(HttpServletRequest request){
    URL url = new URL(request.getRequestURL().toString());
    String host  = url.getHost();
    String userInfo = url.getUserInfo();
    String scheme = url.getProtocol();
    String port = url.getPort();
    String path = request.getAttribute("javax.servlet.forward.request_uri");
    String query = request.getAttribute("javax.servlet.forward.query_string");

    URI uri = new URI(scheme,userInfo,host,port,path,query,null)
    return uri.toString();
}

How to create a thread?

Update The currently suggested way to start a Task is simply using Task.Run()

Task.Run(() => foo());

Note that this method is described as the best way to start a task see here

Previous answer

I like the Task Factory from System.Threading.Tasks. You can do something like this:

Task.Factory.StartNew(() => 
{
    // Whatever code you want in your thread
});

Note that the task factory gives you additional convenience options like ContinueWith:

Task.Factory.StartNew(() => {}).ContinueWith((result) => 
{
    // Whatever code should be executed after the newly started thread.
});

Also note that a task is a slightly different concept than threads. They nicely fit with the async/await keywords, see here.

Twitter Bootstrap: Print content of modal window

I just use a bit of jQuery/javascript:

html:

<h1>Don't Print</h1>

<a data-target="#myModal" role="button" class="btn" data-toggle="modal">Launch modal</a>

<div class="modal fade hide" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel"      aria-hidden="true">
  <div class="modal-header">
    <button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
     <h3 id="myModalLabel">Modal to print</h3>
  </div>
  <div class="modal-body">
    <p>Print Me</p>
  </div>
  <div class="modal-footer">
    <button class="btn" data-dismiss="modal" aria-hidden="true">Close</button>
    <button class="btn btn-primary" id="printButton">Print</button>
  </div>
</div>

js:

$('#printButton').on('click', function () {
    if ($('.modal').is(':visible')) {
        var modalId = $(event.target).closest('.modal').attr('id');
        $('body').css('visibility', 'hidden');
        $("#" + modalId).css('visibility', 'visible');
        $('#' + modalId).removeClass('modal');
        window.print();
        $('body').css('visibility', 'visible');
        $('#' + modalId).addClass('modal');
    } else {
        window.print();
    }
});

here is the fiddle

Using multiple arguments for string formatting in Python (e.g., '%s ... %s')

On a tuple/mapping object for multiple argument format

The following is excerpt from the documentation:

Given format % values, % conversion specifications in format are replaced with zero or more elements of values. The effect is similar to the using sprintf() in the C language.

If format requires a single argument, values may be a single non-tuple object. Otherwise, values must be a tuple with exactly the number of items specified by the format string, or a single mapping object (for example, a dictionary).

References


On str.format instead of %

A newer alternative to % operator is to use str.format. Here's an excerpt from the documentation:

str.format(*args, **kwargs)

Perform a string formatting operation. The string on which this method is called can contain literal text or replacement fields delimited by braces {}. Each replacement field contains either the numeric index of a positional argument, or the name of a keyword argument. Returns a copy of the string where each replacement field is replaced with the string value of the corresponding argument.

This method is the new standard in Python 3.0, and should be preferred to % formatting.

References


Examples

Here are some usage examples:

>>> '%s for %s' % ("tit", "tat")
tit for tat

>>> '{} and {}'.format("chicken", "waffles")
chicken and waffles

>>> '%(last)s, %(first)s %(last)s' % {'first': "James", 'last': "Bond"}
Bond, James Bond

>>> '{last}, {first} {last}'.format(first="James", last="Bond")
Bond, James Bond

See also

Integrating CSS star rating into an HTML form

CSS:

.rate-container > i {
    float: right;
}

.rate-container > i:HOVER,
.rate-container > i:HOVER ~ i {
    color: gold;
}

HTML:

<div class="rate-container">
    <i class="fa fa-star "></i>
    <i class="fa fa-star "></i>
    <i class="fa fa-star "></i>
    <i class="fa fa-star "></i>
    <i class="fa fa-star "></i>
</div>

How can I setup & run PhantomJS on Ubuntu?

in my vagrant bootstrap:

apt-get install -y build-essential chrpath git-core libssl-dev libfontconfig1-dev
git clone git://github.com/ariya/phantomjs.git
cd phantomjs
git checkout 1.9
echo y | ./build.sh
ln -s /home/vagrant/phantomjs/bin/phantomjs /usr/local/bin/phantomjs
cd ..

What is the default encoding of the JVM?

To get default java settings just use :

java -XshowSettings 

putting a php variable in a HTML form value

value="<?php echo htmlspecialchars($name); ?>"

Installing Android Studio, does not point to a valid JVM installation error

In my case, it started hapenning after I updated to Android Studio 1.2. To fix it I just had to remove "\bin" from my JAVA_HOME variable.

How to remove trailing and leading whitespace for user-provided input in a batch file?

Thank you @Bradley Mountford

I'm using the "Trim Right Whitespace" exactly working on my "Show-Grp-of-UID.CMD". :) Other idea for improvement are welcome.. ^_^

Is it possible to decrypt SHA1

Since SHA-1 maps several byte sequences to one, you can't "decrypt" a hash, but in theory you can find collisions: strings that have the same hash.

It seems that breaking a single hash would cost about 2.7 million dollars worth of computer time currently, so your efforts are probably better spent somewhere else.

Angular - How to apply [ngStyle] conditions

<ion-col size="12">
  <ion-card class="box-shadow ion-text-center background-size"
  *ngIf="data != null"
  [ngStyle]="{'background-image': 'url(' + data.headerImage + ')'}">

  </ion-card>

Getting a list item by index

You can use the ElementAt extension method on the list.

For example:

// Get the first item from the list

using System.Linq;

var myList = new List<string>{ "Yes", "No", "Maybe"};
var firstItem = myList.ElementAt(0);

// Do something with firstItem

android fragment- How to save states of views in a fragment when another fragment is pushed on top of it

The Best Solution I found is below:

onSavedInstanceState(): always called inside fragment when activity is going to shut down(Move activity from one to another or config changes). So if we are calling multiple fragments on same activity then We have to use the following approach:

Use OnDestroyView() of the fragment and save the whole object inside that method. Then OnActivityCreated(): Check that if object is null or not(Because this method calls every time). Now restore state of an object here.

Its works always!

Powershell import-module doesn't find modules

Some plugins require one to run as an Administrator and will not load unless one has those credentials active in the shell.

Row count where data exists

Assuming that your Sheet1 is not necessary active you would need to use this improved code of yours:

i = ActiveWorkbook.Worksheets("Sheet1").Range("A2" , Worksheets("Sheet1").Range("A2").End(xlDown)).Rows.Count

Look into full worksheet reference for second argument for Range(arg1, arg2) which important in this situation.

Java Class.cast() vs. cast operator

It's always problematic and often misleading to try and translate constructs and concepts between languages. Casting is no exception. Particularly because Java is a dynamic language and C++ is somewhat different.

All casting in Java, no matter how you do it, is done at runtime. Type information is held at runtime. C++ is a bit more of a mix. You can cast a struct in C++ to another and it's merely a reinterpretation of the bytes that represent those structs. Java doesn't work that way.

Also generics in Java and C++ are vastly different. Don't concern yourself overly with how you do C++ things in Java. You need to learn how to do things the Java way.

Why is Spring's ApplicationContext.getBean considered bad?

I mentioned this in a comment on the other question, but the whole idea of Inversion of Control is to have none of your classes know or care how they get the objects they depend on. This makes it easy to change what type of implementation of a given dependency you use at any time. It also makes the classes easy to test, as you can provide mock implementations of dependencies. Finally, it makes the classes simpler and more focused on their core responsibility.

Calling ApplicationContext.getBean() is not Inversion of Control! While it's still easy to change what implemenation is configured for the given bean name, the class now relies directly on Spring to provide that dependency and can't get it any other way. You can't just make your own mock implementation in a test class and pass that to it yourself. This basically defeats Spring's purpose as a dependency injection container.

Everywhere you want to say:

MyClass myClass = applicationContext.getBean("myClass");

you should instead, for example, declare a method:

public void setMyClass(MyClass myClass) {
   this.myClass = myClass;
}

And then in your configuration:

<bean id="myClass" class="MyClass">...</bean>

<bean id="myOtherClass" class="MyOtherClass">
   <property name="myClass" ref="myClass"/>
</bean>

Spring will then automatically inject myClass into myOtherClass.

Declare everything in this way, and at the root of it all have something like:

<bean id="myApplication" class="MyApplication">
   <property name="myCentralClass" ref="myCentralClass"/>
   <property name="myOtherCentralClass" ref="myOtherCentralClass"/>
</bean>

MyApplication is the most central class, and depends at least indirectly on every other service in your program. When bootstrapping, in your main method, you can call applicationContext.getBean("myApplication") but you should not need to call getBean() anywhere else!

Iterate over array of objects in Typescript

You can use the built-in forEach function for arrays.

Like this:

//this sets all product descriptions to a max length of 10 characters
data.products.forEach( (element) => {
    element.product_desc = element.product_desc.substring(0,10);
});

Your version wasn't wrong though. It should look more like this:

for(let i=0; i<data.products.length; i++){
    console.log(data.products[i].product_desc); //use i instead of 0
}

How to convert wstring into string?

At the time of writing this answer, the number one google search for "convert string wstring" would land you on this page. My answer shows how to convert string to wstring, although this is NOT the actual question, and I should probably delete this answer but that is considered bad form. You may want to jump to this StackOverflow answer, which is now higher ranked than this page.


Here's a way to combining string, wstring and mixed string constants to wstring. Use the wstringstream class.

#include <sstream>

std::string narrow = "narrow";
std::wstring wide = "wide";

std::wstringstream cls;
cls << " abc " << narrow.c_str() << L" def " << wide.c_str();
std::wstring total= cls.str();

Ship an application with a database

There are two options for creating and updating databases.

One is to create a database externally, then place it in the assets folder of the project and then copy the entire database from there. This is much quicker if the database has a lot of tables and other components. Upgrades are triggered by changing the database version number in the res/values/strings.xml file. Upgrades would then be accomplished by creating a new database externally, replacing the old database in the assets folder with the new database, saving the old database in internal storage under another name, copying the new database from the assets folder into internal storage, transferring all of the data from the old database (that was renamed earlier) into the new database and finally deleting the old database. You can create a database originally by using the SQLite Manager FireFox plugin to execute your creation sql statements.

The other option is to create a database internally from a sql file. This is not as quick but the delay would probably be unnoticeable to the users if the database has only a few tables. Upgrades are triggered by changing the database version number in the res/values/strings.xml file. Upgrades would then be accomplished by processing an upgrade sql file. The data in the database will remain unchanged except when its container is removed, for example dropping a table.

The example below demonstrates how to use either method.

Here is a sample create_database.sql file. It is to be placed in the assets folder of the project for the internal method or copied into the "Execute SQL' of SQLite Manager to create the database for the external method. (NOTE: Notice the comment about the table required by Android.)

--Android requires a table named 'android_metadata' with a 'locale' column
CREATE TABLE "android_metadata" ("locale" TEXT DEFAULT 'en_US');
INSERT INTO "android_metadata" VALUES ('en_US');

CREATE TABLE "kitchen_table";
CREATE TABLE "coffee_table";
CREATE TABLE "pool_table";
CREATE TABLE "dining_room_table";
CREATE TABLE "card_table"; 

Here is a sample update_database.sql file. It is to be placed in the assets folder of the project for the internal method or copied into the "Execute SQL' of SQLite Manager to create the database for the external method. (NOTE: Notice that all three types of SQL comments will be ignored by the sql parser that is included in this example.)

--CREATE TABLE "kitchen_table";  This is one type of comment in sql.  It is ignored by parseSql.
/*
 * CREATE TABLE "coffee_table"; This is a second type of comment in sql.  It is ignored by parseSql.
 */
{
CREATE TABLE "pool_table";  This is a third type of comment in sql.  It is ignored by parseSql.
}
/* CREATE TABLE "dining_room_table"; This is a second type of comment in sql.  It is ignored by parseSql. */
{ CREATE TABLE "card_table"; This is a third type of comment in sql.  It is ignored by parseSql. }

--DROP TABLE "picnic_table"; Uncomment this if picnic table was previously created and now is being replaced.
CREATE TABLE "picnic_table" ("plates" TEXT);
INSERT INTO "picnic_table" VALUES ('paper');

Here is an entry to add to the /res/values/strings.xml file for the database version number.

<item type="string" name="databaseVersion" format="integer">1</item>

Here is an activity that accesses the database and then uses it. (Note: You might want to run the database code in a separate thread if it uses a lot of resources.)

package android.example;

import android.app.Activity;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;

/**
 * @author Danny Remington - MacroSolve
 * 
 *         Activity for demonstrating how to use a sqlite database.
 */
public class Database extends Activity {
     /** Called when the activity is first created. */
     @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        DatabaseHelper myDbHelper;
        SQLiteDatabase myDb = null;

        myDbHelper = new DatabaseHelper(this);
        /*
         * Database must be initialized before it can be used. This will ensure
         * that the database exists and is the current version.
         */
         myDbHelper.initializeDataBase();

         try {
            // A reference to the database can be obtained after initialization.
            myDb = myDbHelper.getWritableDatabase();
            /*
             * Place code to use database here.
             */
         } catch (Exception ex) {
            ex.printStackTrace();
         } finally {
            try {
                myDbHelper.close();
            } catch (Exception ex) {
                ex.printStackTrace();
            } finally {
                myDb.close();
            }
        }

    }
}

Here is the database helper class where the database is created or updated if necessary. (NOTE: Android requires that you create a class that extends SQLiteOpenHelper in order to work with a Sqlite database.)

package android.example;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

/**
 * @author Danny Remington - MacroSolve
 * 
 *         Helper class for sqlite database.
 */
public class DatabaseHelper extends SQLiteOpenHelper {

    /*
     * The Android's default system path of the application database in internal
     * storage. The package of the application is part of the path of the
     * directory.
     */
    private static String DB_DIR = "/data/data/android.example/databases/";
    private static String DB_NAME = "database.sqlite";
    private static String DB_PATH = DB_DIR + DB_NAME;
    private static String OLD_DB_PATH = DB_DIR + "old_" + DB_NAME;

    private final Context myContext;

    private boolean createDatabase = false;
    private boolean upgradeDatabase = false;

    /**
     * Constructor Takes and keeps a reference of the passed context in order to
     * access to the application assets and resources.
     * 
     * @param context
     */
    public DatabaseHelper(Context context) {
        super(context, DB_NAME, null, context.getResources().getInteger(
                R.string.databaseVersion));
        myContext = context;
        // Get the path of the database that is based on the context.
        DB_PATH = myContext.getDatabasePath(DB_NAME).getAbsolutePath();
    }

    /**
     * Upgrade the database in internal storage if it exists but is not current. 
     * Create a new empty database in internal storage if it does not exist.
     */
    public void initializeDataBase() {
        /*
         * Creates or updates the database in internal storage if it is needed
         * before opening the database. In all cases opening the database copies
         * the database in internal storage to the cache.
         */
        getWritableDatabase();

        if (createDatabase) {
            /*
             * If the database is created by the copy method, then the creation
             * code needs to go here. This method consists of copying the new
             * database from assets into internal storage and then caching it.
             */
            try {
                /*
                 * Write over the empty data that was created in internal
                 * storage with the one in assets and then cache it.
                 */
                copyDataBase();
            } catch (IOException e) {
                throw new Error("Error copying database");
            }
        } else if (upgradeDatabase) {
            /*
             * If the database is upgraded by the copy and reload method, then
             * the upgrade code needs to go here. This method consists of
             * renaming the old database in internal storage, create an empty
             * new database in internal storage, copying the database from
             * assets to the new database in internal storage, caching the new
             * database from internal storage, loading the data from the old
             * database into the new database in the cache and then deleting the
             * old database from internal storage.
             */
            try {
                FileHelper.copyFile(DB_PATH, OLD_DB_PATH);
                copyDataBase();
                SQLiteDatabase old_db = SQLiteDatabase.openDatabase(OLD_DB_PATH, null, SQLiteDatabase.OPEN_READWRITE);
                SQLiteDatabase new_db = SQLiteDatabase.openDatabase(DB_PATH,null, SQLiteDatabase.OPEN_READWRITE);
                /*
                 * Add code to load data into the new database from the old
                 * database and then delete the old database from internal
                 * storage after all data has been transferred.
                 */
            } catch (IOException e) {
                throw new Error("Error copying database");
            }
        }

    }

    /**
     * Copies your database from your local assets-folder to the just created
     * empty database in the system folder, from where it can be accessed and
     * handled. This is done by transfering bytestream.
     * */
    private void copyDataBase() throws IOException {
        /*
         * Close SQLiteOpenHelper so it will commit the created empty database
         * to internal storage.
         */
        close();

        /*
         * Open the database in the assets folder as the input stream.
         */
        InputStream myInput = myContext.getAssets().open(DB_NAME);

        /*
         * Open the empty db in interal storage as the output stream.
         */
        OutputStream myOutput = new FileOutputStream(DB_PATH);

        /*
         * Copy over the empty db in internal storage with the database in the
         * assets folder.
         */
        FileHelper.copyFile(myInput, myOutput);

        /*
         * Access the copied database so SQLiteHelper will cache it and mark it
         * as created.
         */
        getWritableDatabase().close();
    }

    /*
     * This is where the creation of tables and the initial population of the
     * tables should happen, if a database is being created from scratch instead
     * of being copied from the application package assets. Copying a database
     * from the application package assets to internal storage inside this
     * method will result in a corrupted database.
     * <P>
     * NOTE: This method is normally only called when a database has not already
     * been created. When the database has been copied, then this method is
     * called the first time a reference to the database is retrieved after the
     * database is copied since the database last cached by SQLiteOpenHelper is
     * different than the database in internal storage.
     */
    @Override
    public void onCreate(SQLiteDatabase db) {
        /*
         * Signal that a new database needs to be copied. The copy process must
         * be performed after the database in the cache has been closed causing
         * it to be committed to internal storage. Otherwise the database in
         * internal storage will not have the same creation timestamp as the one
         * in the cache causing the database in internal storage to be marked as
         * corrupted.
         */
        createDatabase = true;

        /*
         * This will create by reading a sql file and executing the commands in
         * it.
         */
            // try {
            // InputStream is = myContext.getResources().getAssets().open(
            // "create_database.sql");
            //
            // String[] statements = FileHelper.parseSqlFile(is);
            //
            // for (String statement : statements) {
            // db.execSQL(statement);
            // }
            // } catch (Exception ex) {
            // ex.printStackTrace();
            // }
    }

    /**
     * Called only if version number was changed and the database has already
     * been created. Copying a database from the application package assets to
     * the internal data system inside this method will result in a corrupted
     * database in the internal data system.
     */
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        /*
         * Signal that the database needs to be upgraded for the copy method of
         * creation. The copy process must be performed after the database has
         * been opened or the database will be corrupted.
         */
        upgradeDatabase = true;

        /*
         * Code to update the database via execution of sql statements goes
         * here.
         */

        /*
         * This will upgrade by reading a sql file and executing the commands in
         * it.
         */
        // try {
        // InputStream is = myContext.getResources().getAssets().open(
        // "upgrade_database.sql");
        //
        // String[] statements = FileHelper.parseSqlFile(is);
        //
        // for (String statement : statements) {
        // db.execSQL(statement);
        // }
        // } catch (Exception ex) {
        // ex.printStackTrace();
        // }
    }

    /**
     * Called everytime the database is opened by getReadableDatabase or
     * getWritableDatabase. This is called after onCreate or onUpgrade is
     * called.
     */
    @Override
    public void onOpen(SQLiteDatabase db) {
        super.onOpen(db);
    }

    /*
     * Add your public helper methods to access and get content from the
     * database. You could return cursors by doing
     * "return myDataBase.query(....)" so it'd be easy to you to create adapters
     * for your views.
     */

}

Here's the FileHelper class that contains methods for byte stream copying files and parsing sql files.

package android.example;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.Reader;
import java.nio.channels.FileChannel;

/**
 * @author Danny Remington - MacroSolve
 * 
 *         Helper class for common tasks using files.
 * 
 */
public class FileHelper {
    /**
     * Creates the specified <i><b>toFile</b></i> that is a byte for byte a copy
     * of <i><b>fromFile</b></i>. If <i><b>toFile</b></i> already existed, then
     * it will be replaced with a copy of <i><b>fromFile</b></i>. The name and
     * path of <i><b>toFile</b></i> will be that of <i><b>toFile</b></i>. Both
     * <i><b>fromFile</b></i> and <i><b>toFile</b></i> will be closed by this
     * operation.
     * 
     * @param fromFile
     *            - InputStream for the file to copy from.
     * @param toFile
     *            - InputStream for the file to copy to.
     */
    public static void copyFile(InputStream fromFile, OutputStream toFile) throws IOException {
        // transfer bytes from the inputfile to the outputfile
        byte[] buffer = new byte[1024];
        int length;

        try {
            while ((length = fromFile.read(buffer)) > 0) {
                toFile.write(buffer, 0, length);
            }
        }
        // Close the streams
        finally {
            try {
                if (toFile != null) {
                    try {
                        toFile.flush();
                    } finally {
                        toFile.close();
                    }
            }
            } finally {
                if (fromFile != null) {
                    fromFile.close();
                }
            }
        }
    }

    /**
     * Creates the specified <i><b>toFile</b></i> that is a byte for byte a copy
     * of <i><b>fromFile</b></i>. If <i><b>toFile</b></i> already existed, then
     * it will be replaced with a copy of <i><b>fromFile</b></i>. The name and
     * path of <i><b>toFile</b></i> will be that of <i><b>toFile</b></i>. Both
     * <i><b>fromFile</b></i> and <i><b>toFile</b></i> will be closed by this
     * operation.
     * 
     * @param fromFile
     *            - String specifying the path of the file to copy from.
     * @param toFile
     *            - String specifying the path of the file to copy to.
     */
    public static void copyFile(String fromFile, String toFile) throws IOException {
        copyFile(new FileInputStream(fromFile), new FileOutputStream(toFile));
    }

    /**
     * Creates the specified <i><b>toFile</b></i> that is a byte for byte a copy
     * of <i><b>fromFile</b></i>. If <i><b>toFile</b></i> already existed, then
     * it will be replaced with a copy of <i><b>fromFile</b></i>. The name and
     * path of <i><b>toFile</b></i> will be that of <i><b>toFile</b></i>. Both
     * <i><b>fromFile</b></i> and <i><b>toFile</b></i> will be closed by this
     * operation.
     * 
     * @param fromFile
     *            - File for the file to copy from.
     * @param toFile
     *            - File for the file to copy to.
     */
    public static void copyFile(File fromFile, File toFile) throws IOException {
        copyFile(new FileInputStream(fromFile), new FileOutputStream(toFile));
    }

    /**
     * Creates the specified <i><b>toFile</b></i> that is a byte for byte a copy
     * of <i><b>fromFile</b></i>. If <i><b>toFile</b></i> already existed, then
     * it will be replaced with a copy of <i><b>fromFile</b></i>. The name and
     * path of <i><b>toFile</b></i> will be that of <i><b>toFile</b></i>. Both
     * <i><b>fromFile</b></i> and <i><b>toFile</b></i> will be closed by this
     * operation.
     * 
     * @param fromFile
     *            - FileInputStream for the file to copy from.
     * @param toFile
     *            - FileInputStream for the file to copy to.
     */
    public static void copyFile(FileInputStream fromFile, FileOutputStream toFile) throws IOException {
        FileChannel fromChannel = fromFile.getChannel();
        FileChannel toChannel = toFile.getChannel();

        try {
            fromChannel.transferTo(0, fromChannel.size(), toChannel);
        } finally {
            try {
                if (fromChannel != null) {
                    fromChannel.close();
                }
            } finally {
                if (toChannel != null) {
                    toChannel.close();
                }
            }
        }
    }

    /**
     * Parses a file containing sql statements into a String array that contains
     * only the sql statements. Comments and white spaces in the file are not
     * parsed into the String array. Note the file must not contained malformed
     * comments and all sql statements must end with a semi-colon ";" in order
     * for the file to be parsed correctly. The sql statements in the String
     * array will not end with a semi-colon ";".
     * 
     * @param sqlFile
     *            - String containing the path for the file that contains sql
     *            statements.
     * 
     * @return String array containing the sql statements.
     */
    public static String[] parseSqlFile(String sqlFile) throws IOException {
        return parseSqlFile(new BufferedReader(new FileReader(sqlFile)));
    }

    /**
     * Parses a file containing sql statements into a String array that contains
     * only the sql statements. Comments and white spaces in the file are not
     * parsed into the String array. Note the file must not contained malformed
     * comments and all sql statements must end with a semi-colon ";" in order
     * for the file to be parsed correctly. The sql statements in the String
     * array will not end with a semi-colon ";".
     * 
     * @param sqlFile
     *            - InputStream for the file that contains sql statements.
     * 
     * @return String array containing the sql statements.
     */
    public static String[] parseSqlFile(InputStream sqlFile) throws IOException {
        return parseSqlFile(new BufferedReader(new InputStreamReader(sqlFile)));
    }

    /**
     * Parses a file containing sql statements into a String array that contains
     * only the sql statements. Comments and white spaces in the file are not
     * parsed into the String array. Note the file must not contained malformed
     * comments and all sql statements must end with a semi-colon ";" in order
     * for the file to be parsed correctly. The sql statements in the String
     * array will not end with a semi-colon ";".
     * 
     * @param sqlFile
     *            - Reader for the file that contains sql statements.
     * 
     * @return String array containing the sql statements.
     */
    public static String[] parseSqlFile(Reader sqlFile) throws IOException {
        return parseSqlFile(new BufferedReader(sqlFile));
    }

    /**
     * Parses a file containing sql statements into a String array that contains
     * only the sql statements. Comments and white spaces in the file are not
     * parsed into the String array. Note the file must not contained malformed
     * comments and all sql statements must end with a semi-colon ";" in order
     * for the file to be parsed correctly. The sql statements in the String
     * array will not end with a semi-colon ";".
     * 
     * @param sqlFile
     *            - BufferedReader for the file that contains sql statements.
     * 
     * @return String array containing the sql statements.
     */
    public static String[] parseSqlFile(BufferedReader sqlFile) throws IOException {
        String line;
        StringBuilder sql = new StringBuilder();
        String multiLineComment = null;

        while ((line = sqlFile.readLine()) != null) {
            line = line.trim();

            // Check for start of multi-line comment
            if (multiLineComment == null) {
                // Check for first multi-line comment type
                if (line.startsWith("/*")) {
                    if (!line.endsWith("}")) {
                        multiLineComment = "/*";
                    }
                // Check for second multi-line comment type
                } else if (line.startsWith("{")) {
                    if (!line.endsWith("}")) {
                        multiLineComment = "{";
                }
                // Append line if line is not empty or a single line comment
                } else if (!line.startsWith("--") && !line.equals("")) {
                    sql.append(line);
                } // Check for matching end comment
            } else if (multiLineComment.equals("/*")) {
                if (line.endsWith("*/")) {
                    multiLineComment = null;
                }
            // Check for matching end comment
            } else if (multiLineComment.equals("{")) {
                if (line.endsWith("}")) {
                    multiLineComment = null;
                }
            }

        }

        sqlFile.close();

        return sql.toString().split(";");
    }

}

Java Embedded Databases Comparison

I personally favor HSQLDB, but mostly because it was the first I tried.

H2 is said to be faster and provides a nicer GUI frontend (which is generic and works with any JDBC driver, by the way).

At least HSQLDB, H2 and Derby provide server modes which is great for development, because you can access the DB with your application and some tool at the same time (which embedded mode usually doesn't allow).

Left Outer Join using + sign in Oracle 11g

LEFT OUTER JOIN

SELECT * FROM A, B WHERE A.column = B.column(+)

RIGHT OUTER JOIN

SELECT * FROM A, B WHERE A.column (+)= B.column

Easiest way to rotate by 90 degrees an image using OpenCV?

Here's my EmguCV (a C# port of OpenCV) solution:

public static Image<TColor, TDepth> Rotate90<TColor, TDepth>(this Image<TColor, TDepth> img)
    where TColor : struct, IColor
    where TDepth : new()
{
    var rot = new Image<TColor, TDepth>(img.Height, img.Width);
    CvInvoke.cvTranspose(img.Ptr, rot.Ptr);
    rot._Flip(FLIP.HORIZONTAL);
    return rot;
}

public static Image<TColor, TDepth> Rotate180<TColor, TDepth>(this Image<TColor, TDepth> img)
    where TColor : struct, IColor
    where TDepth : new()
{
    var rot = img.CopyBlank();
    rot = img.Flip(FLIP.VERTICAL);
    rot._Flip(FLIP.HORIZONTAL);
    return rot;
}

public static void _Rotate180<TColor, TDepth>(this Image<TColor, TDepth> img)
    where TColor : struct, IColor
    where TDepth : new()
{
    img._Flip(FLIP.VERTICAL);
    img._Flip(FLIP.HORIZONTAL);
}

public static Image<TColor, TDepth> Rotate270<TColor, TDepth>(this Image<TColor, TDepth> img)
    where TColor : struct, IColor
    where TDepth : new()
{
    var rot = new Image<TColor, TDepth>(img.Height, img.Width);
    CvInvoke.cvTranspose(img.Ptr, rot.Ptr);
    rot._Flip(FLIP.VERTICAL);
    return rot;
}

Shouldn't be too hard to translate it back into C++.

How to wait until an element exists?

For a simple approach using jQuery I've found this to work well:

  // Wait for element to exist.
  function elementLoaded(el, cb) {
    if ($(el).length) {
      // Element is now loaded.
      cb($(el));
    } else {
      // Repeat every 500ms.
      setTimeout(function() {
        elementLoaded(el, cb)
      }, 500);
    }
  };

  elementLoaded('.element-selector', function(el) {
    // Element is ready to use.
    el.click(function() {
      alert("You just clicked a dynamically inserted element");
    });
  });

Here we simply check every 500ms to see whether the element is loaded, when it is, we can use it.

This is especially useful for adding click handlers to elements which have been dynamically added to the document.

How to move an entire div element up x pixels?

you can also do this

margin-top:-30px; 
min-height:40px;

this "help" to stop the div yanking everything up a bit.

Best way to store time (hh:mm) in a database

The saving of time in UTC format can help better as Kristen suggested.

Make sure that you are using 24 hr clock because there is no meridian AM or PM be used in UTC.

Example:

  • 4:12 AM - 0412
  • 10:12 AM - 1012
  • 2:28 PM - 1428
  • 11:56 PM - 2356

Its still preferrable to use standard four digit format.

How to get min, seconds and milliseconds from datetime.now() in python?

Another similar solution:

>>> a=datetime.now()
>>> "%s:%s.%s" % (a.hour, a.minute, a.microsecond)
'14:28.971209'

Yes, I know I didn't get the string formatting perfect.

Mysql - How to quit/exit from stored procedure

MainLabel:BEGIN

IF (<condition>) IS NOT NULL THEN
    LEAVE MainLabel;
END IF; 

....code

i.e.
IF (@skipMe) IS NOT NULL THEN /* @skipMe returns Null if never set or set to NULL */
     LEAVE MainLabel;
END IF;

AngularJS app.run() documentation?

Specifically...

How and where is app.run() used? After module definition or after app.config(), after app.controller()?

Where:

In your package.js E.g. /packages/dashboard/public/controllers/dashboard.js

How:

Make it look like this

var app = angular.module('mean.dashboard', ['ui.bootstrap']);

app.controller('DashboardController', ['$scope', 'Global', 'Dashboard',
    function($scope, Global, Dashboard) {
        $scope.global = Global;
        $scope.package = {
            name: 'dashboard'
        };
        // ...
    }
]);

app.run(function(editableOptions) {
    editableOptions.theme = 'bs3'; // bootstrap3 theme. Can be also 'bs2', 'default'
});

How can I change the current URL?

<script> 
    var url= "http://www.google.com"; 
    window.location = url; 
</script> 

File 'app/hero.ts' is not a module error in the console, where to store interfaces files in directory structure with angular2?

Open command prompt, go to the app folder, e.g. D:\angular-tour-of-heroes\src\app

Then create a new file using the following command:

ng generate class hero

This will create a hero.ts file. Then you can paste the export code, and the error is gone.

How to run a makefile in Windows?

Here is my quick and temporary way to run a Makefile

  • download make from SourceForge: gnuwin32
  • install it
  • go to the install folder

C:\Program Files (x86)\GnuWin32\bin

  • copy the all files in the bin to the folder that contains Makefile

libiconv2.dll libintl3.dll make.exe

  • open the cmd (you can do it with right click with shift) in the folder that contains Makefile and run

make.exe

done.

Plus, you can add arguments after the command, such as

make.exe skel

String contains another two strings

If you have a list of words you can do a method like this:

public bool ContainWords(List<string> wordList, string text)
{
   foreach(string currentWord in wordList)
      if(!text.Contains(currentWord))
         return false;
   return true;
}

Simplest JQuery validation rules example

The input in the markup is missing "type", the input (text I assume) has the attribute name="name" and ID="cname", the provided code by Ayo calls the input named "cname"* where it should be "name".

Can't compile C program on a Mac after upgrade to Mojave

Be sure to check Xcode Preferences -> Locations.

The Command Line Tools I had selected was for the previous version of Xcode (8.2.1 instead of 10.1)

Stop a gif animation onload, on mouseover start the activation

For restarting the animation of a gif image, you can use the code:

$('#img_gif').attr('src','file.gif?' + Math.random());

Using Apache POI how to read a specific excel column

Okay, from your question, you just simply want to read a particular column. So, while iterating over a row and then on its cells, your can simply check the index of the column.

Iterator<Row> rowIterator = mySheet.iterator(); // Traversing over each row of XLSX file
        while (rowIterator.hasNext()) {
            Row row = rowIterator.next(); // For each row, iterate through each columns
            Iterator<Cell> cellIterator = row.cellIterator();
            while (cellIterator.hasNext()) {
                Cell cell = cellIterator.next();
                println "column index"+cell.getColumnIndex()//You will have your columns fixed in Excel file
                if(cell.getColumnIndex()==3)//for example of c
                {
                print "done"            
                }
          }
     }     

I am using POI 3.12-- 'org.apache.poi:poi:3.12' Hope it helps. Cheers!

Can I create links with 'target="_blank"' in Markdown?

You can do this via native javascript code like so:

 
var pattern = /a href=/g;
var sanitizedMarkDownText = rawMarkDownText.replace(pattern,"a target='_blank' href=");

JSFiddle Code

echo that outputs to stderr

If you don't mind logging the message also to syslog, the not_so_ugly way is:

logger -s $msg

The -s option means: "Output the message to standard error as well as to the system log."

How to get the first non-null value in Java?

With Guava you can do:

Optional.fromNullable(a).or(b);

which doesn't throw NPE if both a and b are null.

EDIT: I was wrong, it does throw NPE. The correct way as commented by Michal Cizmazia is:

Optional.fromNullable(a).or(Optional.fromNullable(b)).orNull();

How to refresh a Page using react-route Link

If you just put '/' in the href it will reload the current window.

_x000D_
_x000D_
<a href="/">
  Reload the page
</a>
_x000D_
_x000D_
_x000D_

Throw keyword in function's signature

A no throw specification on an inlined function that only returns a member variable and could not possibly throw exceptions may be used by some compilers to do pessimizations (a made-up word for the opposite of optimizations) that can have a detrimental effect on performance. This is described in the Boost literature: Exception-specification

With some compilers a no-throw specification on non-inline functions may be beneficial if the correct optimizations are made and the use of that function impacts performance in a way that it justifies it.

To me it sounds like whether to use it or not is a call made by a very critical eye as part of a performance optimization effort, perhaps using profiling tools.

A quote from the above link for those in a hurry (contains an example of bad unintended effects of specifying throw on an inline function from a naive compiler):

Exception-specification rationale

Exception specifications [ISO 15.4] are sometimes coded to indicate what exceptions may be thrown, or because the programmer hopes they will improve performance. But consider the following member from a smart pointer:

T& operator*() const throw() { return *ptr; }

This function calls no other functions; it only manipulates fundamental data types like pointers Therefore, no runtime behavior of the exception-specification can ever be invoked. The function is completely exposed to the compiler; indeed it is declared inline Therefore, a smart compiler can easily deduce that the functions are incapable of throwing exceptions, and make the same optimizations it would have made based on the empty exception-specification. A "dumb" compiler, however, may make all kinds of pessimizations.

For example, some compilers turn off inlining if there is an exception-specification. Some compilers add try/catch blocks. Such pessimizations can be a performance disaster which makes the code unusable in practical applications.

Although initially appealing, an exception-specification tends to have consequences that require very careful thought to understand. The biggest problem with exception-specifications is that programmers use them as though they have the effect the programmer would like, instead of the effect they actually have.

A non-inline function is the one place a "throws nothing" exception-specification may have some benefit with some compilers.

How to fix Error: "Could not find schema information for the attribute/element" by creating schema

When this happened to me (out of nowhere) I was about to dive into the top answer above, and then I figured I'd close the project, close Visual Studio, and then re-open everything. Problem solved. VS bug?

Django Model() vs Model.objects.create()

The two syntaxes are not equivalent and it can lead to unexpected errors. Here is a simple example showing the differences. If you have a model:

from django.db import models

class Test(models.Model):

    added = models.DateTimeField(auto_now_add=True)

And you create a first object:

foo = Test.objects.create(pk=1)

Then you try to create an object with the same primary key:

foo_duplicate = Test.objects.create(pk=1)
# returns the error:
# django.db.utils.IntegrityError: (1062, "Duplicate entry '1' for key 'PRIMARY'")

foo_duplicate = Test(pk=1).save()
# returns the error:
# django.db.utils.IntegrityError: (1048, "Column 'added' cannot be null")

Is there a NumPy function to return the first index of something in an array?

There are lots of operations in NumPy that could perhaps be put together to accomplish this. This will return indices of elements equal to item:

numpy.nonzero(array - item)

You could then take the first elements of the lists to get a single element.

File opens instead of downloading in internet explorer in a href link

Zip your file (.zip) and IE will give the user the option to open or download the file.

How to change values in a tuple?

It is possible with a one liner:

values = ('275', '54000', '0.0', '5000.0', '0.0')
values = ('300', *values[1:])

How to get Locale from its String representation in Java?

Since Java 7 there is factory method Locale.forLanguageTag and instance method Locale.toLanguageTag using IETF language tags.

Time complexity of Euclid's Algorithm

The suitable way to analyze an algorithm is by determining its worst case scenarios. Euclidean GCD's worst case occurs when Fibonacci Pairs are involved. void EGCD(fib[i], fib[i - 1]), where i > 0.

For instance, let's opt for the case where the dividend is 55, and the divisor is 34 (recall that we are still dealing with fibonacci numbers).

enter image description here

As you may notice, this operation costed 8 iterations (or recursive calls).

Let's try larger Fibonacci numbers, namely 121393 and 75025. We can notice here as well that it took 24 iterations (or recursive calls).

enter image description here

You can also notice that each iterations yields a Fibonacci number. That's why we have so many operations. We can't obtain similar results only with Fibonacci numbers indeed.

Hence, the time complexity is going to be represented by small Oh (upper bound), this time. The lower bound is intuitively Omega(1): case of 500 divided by 2, for instance.

Let's solve the recurrence relation:

enter image description here

We may say then that Euclidean GCD can make log(xy) operation at most.

How to symbolicate crash log Xcode?

You can refer this one too, I have written step by step procedure of Manual Crash Re-Symbolication.

Crash Re-Symbolication

STEP 1

Move all the above files (MyApp.app, MyApp-dSYM.dSYM and MyApp-Crash-log.crash) into a Folder with a convenient name wherever you can go using Terminal easily.

For me, Desktop is the most easily reachable place ;) So, I have moved these three files into a folder MyApp at Desktop.

STEP 2

Now its turn of Finder, Go to the path from following whichever is applicable for your XCODE version.

Use this command to find the symbolicatecrash script file,
find /Applications/Xcode.app -name symbolicatecrash

Xcode 8, Xcode 9, Xcode 11 /Applications/Xcode.app/Contents/SharedFrameworks/DVTFoundation.framework/Versions/A/Resources/symbolicatecrash

Xcode 7.3 /Applications/Xcode.app/Contents/SharedFrameworks/DVTFoundation.framework/Versions/A/Resources/symbolicatecrash

XCode 7 /Applications/Xcode.app/Contents/SharedFrameworks/DTDeviceKitBase.framework/Versions/A/Resources/symbolicatecrash

Xcode 6 /Applications/Xcode.app/Contents/SharedFrameworks/DTDeviceKitBase.framework/Versions/A/Resources

Lower then Xcode 6 Contents/Developer/Platforms/iPhoneOS.platform/Developer/Library/PrivateFrameworks/DTDeviceKitBase.framework/Versions/A/Resources

Or Contents/Developer/Platforms/iPhoneOS.platform/Developer/Library/PrivateFrameworks/DTDeviceKit.framework/Versions/A/Resources

STEP 3

Add the found symbolicatecrash script file's directory to $PATH env variable like this: sudo vim /etc/paths.d/Xcode-symbolicatecrash and paste the script file's directory and save the file. When opening a new terminal, you can call symbolicatecrash at any folder as commands located in /usr/bin.

Or

Copy symbolicatecrash file from this location, and paste it to the Desktop/MyApp (Wait… Don’t blindly follow me, I am pasting sybolicatecrash file in folder MyApp, one that you created in step one at your favorite location, having three files.)

STEP 4

Open Terminal, and CD to the MyApp Folder.

cd Desktop/MyApp — Press Enter
export DEVELOPER_DIR=$(xcode-select --print-path)

Press Enter

./symbolicatecrash -v MyApp-Crash-log.crash MyApp.dSYM

Press Enter

That’s it !! Symbolicated logs are on your terminal… now what are you waiting for? Now simply, Find out the Error and resolve it ;)

Happy Coding !!!

Get array of object's keys

If you decide to use Underscore.js you better do

var foo = { 'alpha' : 'puffin', 'beta' : 'beagle' };
var keys = [];
_.each( foo, function( val, key ) {
    keys.push(key);
});
console.log(keys);

difference between new String[]{} and new String[] in java

{} defines the contents of the array, in this case it is empty. These would both have an array of three Strings

String[] array = {"element1","element2","element3"};
String[] array = new String[] {"element1","element2","element3"};

while [] on the expression side (right side of =) of a statement defines the size of an intended array, e.g. this would have an array of 10 locations to place Strings

String[] array = new String[10];

...But...

String array = new String[10]{};  //The line you mentioned above

Was wrong because you are defining an array of length 10 ([10]), then defining an array of length 0 ({}), and trying to set them to the same array reference (array) in one statement. Both cannot be set.

Additionally

The array should be defined as an array of a given type at the start of the statement like String[] array. String array = /* array value*/ is saying, set an array value to a String, not to an array of Strings.

How to select <td> of the <table> with javascript?

var t = document.getElementById("table"),
    d = t.getElementsByTagName("tr"),
    r = d.getElementsByTagName("td");

needs to be:

var t = document.getElementById("table"),
    tableRows = t.getElementsByTagName("tr"),
    r = [], i, len, tds, j, jlen;

for ( i =0, len = tableRows.length; i<len; i++) {
    tds = tableRows[i].getElementsByTagName('td');
    for( j = 0, jlen = tds.length; j < jlen; j++) {
        r.push(tds[j]);
    }
}

Because getElementsByTagName returns a NodeList an Array-like structure. So you need to loop through the return nodes and then populate you r like above.

Call an activity method from a fragment

This is From Fragment class...

((KidsStoryDashboard)getActivity()).values(title_txt,bannerImgUrl);

This Code From Activity Class...

 public void values(String title_txts, String bannerImgUrl) {
    if (!title_txts.isEmpty()) {

//Do something to set text 
    }
    imageLoader.displayImage(bannerImgUrl, htab_header_image, doption);
}

Parsing CSV / tab-delimited txt file with Python

Although there is nothing wrong with the other solutions presented, you could simplify and greatly escalate your solutions by using python's excellent library pandas.

Pandas is a library for handling data in Python, preferred by many Data Scientists.

Pandas has a simplified CSV interface to read and parse files, that can be used to return a list of dictionaries, each containing a single line of the file. The keys will be the column names, and the values will be the ones in each cell.

In your case:

    import pandas

    def create_dictionary(filename):
        my_data = pandas.DataFrame.from_csv(filename, sep='\t', index_col=False)
        # Here you can delete the dataframe columns you don't want!
        del my_data['B']
        del my_data['D']
        # ...
        # Now you transform the DataFrame to a list of dictionaries
        list_of_dicts = [item for item in my_data.T.to_dict().values()]
        return list_of_dicts

# Usage:
x = create_dictionary("myfile.csv")

Execution failed for task :':app:mergeDebugResources'. Android Studio

This issue can be resolved by trying multiple solutions like:

  1. Clean the project OR delete build folder and rebuild.
  2. Downgrading gradle version
  3. Check for the generated build file path, as it may be exceeding the windows max path length of 255 characters. Try using short names to make sure your project path is not too long.
  4. You may have a corrupted .9.png in your drawables directory

How can one run multiple versions of PHP 5.x on a development LAMP server?

I have just successfully downgraded from PHP5.3 on Ubuntu 10.

To do this I used the following script:

#! /bin/sh
php_packages=`dpkg -l | grep php | awk '{print $2}'`

sudo apt-get remove $php_packages

sed s/lucid/karmic/g /etc/apt/sources.list | sudo tee /etc/apt/sources.list.d/karmic.list

sudo mkdir -p /etc/apt/preferences.d/

for package in $php_packages;
do echo "Package: $package
Pin: release a=karmic
Pin-Priority: 991
" | sudo tee -a /etc/apt/preferences.d/php
done

sudo apt-get update

sudo apt-get install $php_packages

For anyone that doesn't know how to run scripts from the command line, here is a brief tutorial:

1. cd ~/
2. mkdir bin
3. sudo nano ~/bin/myscriptname.sh
4. paste in the script code I have posted above this
5. ctrl+x (this exits and prompts for you to save)
6. chmod u+x myscriptname.sh

These 6 steps create a script in a folder called "bin" in your home directory. You can then run this script by calling the following command:

~/bin/myscriptname.sh

Oulia!

Hope this helps some of you!

For reference, here is where I got the script: PHP5.2.10 for Ubuntu 10

There are several people on there all confirming that this works, and it worked a treat for me.

How to update-alternatives to Python 3 without breaking apt?

As I didn't want to break anything, I did this to be able to use newer versions of Python3 than Python v3.4 :

$ sudo update-alternatives --install /usr/local/bin/python3 python3 /usr/bin/python3.6 1
update-alternatives: using /usr/bin/python3.6 to provide /usr/local/bin/python3 (python3) in auto mode
$ sudo update-alternatives --install /usr/local/bin/python3 python3 /usr/bin/python3.7 2
update-alternatives: using /usr/bin/python3.7 to provide /usr/local/bin/python3 (python3) in auto mode
$ update-alternatives --list python3
/usr/bin/python3.6
/usr/bin/python3.7
$ sudo update-alternatives --config python3
There are 2 choices for the alternative python3 (providing /usr/local/bin/python3).

  Selection    Path                Priority   Status
------------------------------------------------------------
* 0            /usr/bin/python3.7   2         auto mode
  1            /usr/bin/python3.6   1         manual mode
  2            /usr/bin/python3.7   2         manual mode

Press enter to keep the current choice[*], or type selection number: 1
update-alternatives: using /usr/bin/python3.6 to provide /usr/local/bin/python3 (python3) in manual mode
$ ls -l /usr/local/bin/python3 /etc/alternatives/python3 
lrwxrwxrwx 1 root root 18 2019-05-03 02:59:03 /etc/alternatives/python3 -> /usr/bin/python3.6*
lrwxrwxrwx 1 root root 25 2019-05-03 02:58:53 /usr/local/bin/python3 -> /etc/alternatives/python3*

What is the => assignment in C# in a property signature

You can even write this:

    private string foo = "foo";

    private string bar
    {
        get => $"{foo}bar";
        set
        {
            foo = value;
        }
    }

Create or update mapping in elasticsearch

Generally speaking, you can update your index mapping using the put mapping api (reference here) :

curl -XPUT 'http://localhost:9200/advert_index/_mapping/advert_type' -d '
{
    "advert_type" : {
        "properties" : {

          //your new mapping properties

        }
    }
}
'

It's especially useful for adding new fields. However, in your case, you will try to change the location type, which will cause a conflict and prevent the new mapping from being used.

You could use the put mapping api to add another property containing the location as a lat/lon array, but you won't be able to update the previous location field itself.

Finally, you will have to reindex your data for your new mapping to be taken into account.

The best solution would really be to create a new index.

If your problem with creating another index is downtime, you should take a look at aliases to make things go smoothly.

Retrieve all values from HashMap keys in an ArrayList Java

It has method to find all values from map:

Map<K, V> map=getMapObjectFromXyz();
Collection<V> vs= map.values();
     

Iterate over vs to do some operation

List of foreign keys and the tables they reference in Oracle DB

Its a bit late to anwser, but I hope my answer been useful for someone, who needs to select Composite foreign keys.

SELECT
    "C"."CONSTRAINT_NAME",
    "C"."OWNER" AS "SCHEMA_NAME",
    "C"."TABLE_NAME",
    "COL"."COLUMN_NAME",
    "REF_COL"."OWNER" AS "REF_SCHEMA_NAME",
    "REF_COL"."TABLE_NAME" AS "REF_TABLE_NAME",
    "REF_COL"."COLUMN_NAME" AS "REF_COLUMN_NAME"
FROM
    "USER_CONSTRAINTS" "C"
INNER JOIN "USER_CONS_COLUMNS" "COL" ON "COL"."OWNER" = "C"."OWNER"
 AND "COL"."CONSTRAINT_NAME" = "C"."CONSTRAINT_NAME"
INNER JOIN "USER_CONS_COLUMNS" "REF_COL" ON "REF_COL"."OWNER" = "C"."R_OWNER"
 AND "REF_COL"."CONSTRAINT_NAME" = "C"."R_CONSTRAINT_NAME"
 AND "REF_COL"."POSITION" = "COL"."POSITION"
WHERE "C"."TABLE_NAME" = 'TableName' AND "C"."CONSTRAINT_TYPE" = 'R'

Use multiple css stylesheets in the same html page

You never refer to a specific style sheet. All CSS rules in a document are internally fused into one.

In the case of rules in both style sheets that apply to the same element with the same specificity, the style sheet embedded later will override the earlier one.

You can use an element inspector like Firebug to see which rules apply, and which ones are overridden by others.

Trigger css hover with JS

I don't think what your asking is possible.

See: Hover Item with JQuery

Basically, adding a class is the only way to accomplish this that I am aware of.

Optimal way to Read an Excel file (.xls/.xlsx)

Try to use this free way to this, https://freenetexcel.codeplex.com

 Workbook workbook = new Workbook();

 workbook.LoadFromFile(@"..\..\parts.xls",ExcelVersion.Version97to2003);
 //Initialize worksheet
 Worksheet sheet = workbook.Worksheets[0];

 DataTable dataTable = sheet.ExportDataTable();

How can I require at least one checkbox be checked before a form can be submitted?

<ul>
    <li><input class="checkboxes" name="BoxSelect[]" type="checkbox" value="Box 1" required><label>Box 1</label></li>
    <li><input class="checkboxes" name="BoxSelect[]" type="checkbox" value="Box 2" required><label>Box 2</label></li>
    <li><input class="checkboxes" name="BoxSelect[]" type="checkbox" value="Box 3" required><label>Box 3</label></li>
    <li><input class="checkboxes" name="BoxSelect[]" type="checkbox" value="Box 4" required><label>Box 4</label></li>
</ul>

<script type="text/javascript">
$(document).ready(function(){
    var checkboxes = $('.checkboxes');
    checkboxes.change(function(){
        if($('.checkboxes:checked').length>0) {
            checkboxes.removeAttr('required');
        } else {
            checkboxes.attr('required', 'required');
        }
    });
});
</script>

How to create a blank/empty column with SELECT query in oracle?

In DB2, using single quotes instead of your double quotes will work. So that could translate the same in Oracle..

SELECT CustomerName AS Customer, '' AS Contact 
FROM Customers;

Read and parse a Json File in C#

Doing this yourself is an awful idea. Use Json.NET. It has already solved the problem better than most programmers could if they were given months on end to work on it. As for your specific needs, parsing into arrays and such, check the documentation, particularly on JsonTextReader. Basically, Json.NET handles JSON arrays natively and will parse them into strings, ints, or whatever the type happens to be without prompting from you. Here is a direct link to the basic code usages for both the reader and the writer, so you can have that open in a spare window while you're learning to work with this.

This is for the best: Be lazy this time and use a library so you solve this common problem forever.

Touch move getting stuck Ignored attempt to cancel a touchmove

Please remove e.preventDefault(), because event.cancelable of touchmove is false. So you can't call this method.

JQuery Error: cannot call methods on dialog prior to initialization; attempted to call method 'close'

Looks like your buttons are not declared correctly (according to the latest jQuery UI documentation anyway).

try the following:

$( ".selector" ).dialog({ 
   buttons: [{ 
      text: "Ok", 
      click: function() { 
         $( this ).dialog( "close" ); 
      }
   }]
});

Share link on Google+

<meta property="og:title" content="Ali Umair"/>
<meta property="og:description" content="Ali UMair is a web developer"/><meta property="og:image" content="../image" />

<a target="_blank" href="https://plus.google.com/share?url=<? echo urlencode('http://www..'); ?>"><img src="../gplus-black_icon.png" alt="" /></a>

this code will work with image text and description please put meta into head tag

"RangeError: Maximum call stack size exceeded" Why?

The answer with for is correct, but if you really want to use functional style avoiding for statement - you can use the following instead of your expression:

Array.from(Array(1000000), () => Math.random());

The Array.from() method creates a new Array instance from an array-like or iterable object. The second argument of this method is a map function to call on every element of the array.

Following the same idea you can rewrite it using ES2015 Spread operator:

[...Array(1000000)].map(() => Math.random())

In both examples you can get an index of the iteration if you need, for example:

[...Array(1000000)].map((_, i) => i + Math.random())

Phone number validation Android

^\+201[0|1|2|5][0-9]{8}

this regex matches Egyptian mobile numbers

How to properly set Column Width upon creating Excel file? (Column properties)

I have change all columns width in my case as

            worksheet.Columns[1].ColumnWidth = 7;
            worksheet.Columns[2].ColumnWidth = 15;
            worksheet.Columns[3].ColumnWidth = 15;
            worksheet.Columns[4].ColumnWidth = 15;
            worksheet.Columns[5].ColumnWidth = 18;
            worksheet.Columns[6].ColumnWidth = 8;
            worksheet.Columns[7].ColumnWidth = 13;
            worksheet.Columns[8].ColumnWidth = 17;
            worksheet.Columns[9].ColumnWidth = 17;

Note: Columns in worksheet start with 1 not from 0 as in Arrary.

How to SSH into Docker?

Create docker image with openssh-server preinstalled:

Dockerfile

FROM ubuntu:16.04

RUN apt-get update && apt-get install -y openssh-server
RUN mkdir /var/run/sshd
RUN echo 'root:screencast' | chpasswd
RUN sed -i 's/PermitRootLogin prohibit-password/PermitRootLogin yes/' /etc/ssh/sshd_config

# SSH login fix. Otherwise user is kicked off after login
RUN sed 's@session\s*required\s*pam_loginuid.so@session optional pam_loginuid.so@g' -i /etc/pam.d/sshd

ENV NOTVISIBLE "in users profile"
RUN echo "export VISIBLE=now" >> /etc/profile

EXPOSE 22
CMD ["/usr/sbin/sshd", "-D"]

Build the image using:

$ docker build -t eg_sshd .

Run a test_sshd container:

$ docker run -d -P --name test_sshd eg_sshd
$ docker port test_sshd 22

0.0.0.0:49154

Ssh to your container:

$ ssh [email protected] -p 49154
# The password is ``screencast``.
root@f38c87f2a42d:/#

Source: https://docs.docker.com/engine/examples/running_ssh_service/#build-an-eg_sshd-image

DateTime.Now.ToShortDateString(); replace month and day

Use DateTime.ToString with the specified format MM.dd.yyyy:

this.TextBox3.Text = DateTime.Now.ToString("MM.dd.yyyy");

Here, MM means the month from 01 to 12, dd means the day from 01 to 31 and yyyy means the year as a four-digit number.

CREATE FILE encountered operating system error 5(failed to retrieve text for this error. Reason: 15105)

Right Click on File mdf and ldf properties -> security ->full permission

'numpy.float64' object is not iterable

numpy.linspace() gives you a one-dimensional NumPy array. For example:

>>> my_array = numpy.linspace(1, 10, 10)
>>> my_array
array([  1.,   2.,   3.,   4.,   5.,   6.,   7.,   8.,   9.,  10.])

Therefore:

for index,point in my_array

cannot work. You would need some kind of two-dimensional array with two elements in the second dimension:

>>> two_d = numpy.array([[1, 2], [4, 5]])
>>> two_d
array([[1, 2], [4, 5]])

Now you can do this:

>>> for x, y in two_d:
    print(x, y)

1 2
4 5

New line in JavaScript alert box

use the new line character of a javascript instead of '\n'.. eg: "Hello\nWorld" use "Hello\x0AWorld" It works great!!

Replacing .NET WebBrowser control with a better browser, like Chrome?

I know this isn't a 'replacement' WebBrowser control, but I was having some awful rendering issues whilst showing a page that was using BootStrap 3+ for layout etc, and then I found a post that suggested I use the following. Apparently, it's specific to IE and tells it to use the latest variation found on the client machine for rendering (so it won't use IE7, which I believe is the default).

So just put:

<meta http-equiv="X-UA-Compatible" content="IE=Edge" />

somewhere in the head part of your document.

Obviously, if it's not your document, this won't help - though I personally consider it to be a security hole if you're reading pages not created by yourself through the WebBrowser control - why not just use a web browser!

How to declare local variables in postgresql?

Postgresql historically doesn't support procedural code at the command level - only within functions. However, in Postgresql 9, support has been added to execute an inline code block that effectively supports something like this, although the syntax is perhaps a bit odd, and there are many restrictions compared to what you can do with SQL Server. Notably, the inline code block can't return a result set, so can't be used for what you outline above.

In general, if you want to write some procedural code and have it return a result, you need to put it inside a function. For example:

CREATE OR REPLACE FUNCTION somefuncname() RETURNS int LANGUAGE plpgsql AS $$
DECLARE
  one int;
  two int;
BEGIN
  one := 1;
  two := 2;
  RETURN one + two;
END
$$;
SELECT somefuncname();

The PostgreSQL wire protocol doesn't, as far as I know, allow for things like a command returning multiple result sets. So you can't simply map T-SQL batches or stored procedures to PostgreSQL functions.

How to use SearchView in Toolbar Android

Integrating SearchView with RecyclerView

1) Add SearchView Item in Menu

SearchView can be added as actionView in menu using

app:useActionClass = "android.support.v7.widget.SearchView" .

<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
tools:context="rohksin.com.searchviewdemo.MainActivity">
<item
    android:id="@+id/searchBar"
    app:showAsAction="always"
    app:actionViewClass="android.support.v7.widget.SearchView"
    />
</menu>

2) Implement SearchView.OnQueryTextListener in your Activity

SearchView.OnQueryTextListener has two abstract methods. So your activity skeleton would now look like this after implementing SearchView text listener.

YourActivity extends AppCompatActivity implements SearchView.OnQueryTextListener{

   public boolean onQueryTextSubmit(String query)

   public boolean onQueryTextChange(String newText) 

}

3) Set up SerchView Hint text, listener etc

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main, menu);

    MenuItem searchItem = menu.findItem(R.id.searchBar);

    SearchView searchView = (SearchView) searchItem.getActionView();
    searchView.setQueryHint("Search People");
    searchView.setOnQueryTextListener(this);
    searchView.setIconified(false);

    return true;
}

4) Implement SearchView.OnQueryTextListener

This is how you can implement abstract methods of the listener.

@Override
public boolean onQueryTextSubmit(String query) {

    // This method can be used when a query is submitted eg. creating search history using SQLite DB

    Toast.makeText(this, "Query Inserted", Toast.LENGTH_SHORT).show();
    return true;
}

@Override
public boolean onQueryTextChange(String newText) {

    adapter.filter(newText);
    return true;
}

5) Write a filter method in your RecyclerView Adapter.

You can come up with your own logic based on your requirement. Here is the sample code snippet to show the list of Name which contains the text typed in the SearchView.

public void filter(String queryText)
{
    list.clear();

    if(queryText.isEmpty())
    {
        list.addAll(copyList);
    }
    else
    {

        for(String name: copyList)
        {
            if(name.toLowerCase().contains(queryText.toLowerCase()))
            {
                list.add(name);
            }
        }

    }

    notifyDataSetChanged();
}

Full working code sample can be found > HERE
You can also check out the code on SearchView with an SQLite database in this Music App

Is there a way to get rid of accents and convert a whole string to regular letters?

The solution by @virgo47 is very fast, but approximate. The accepted answer uses Normalizer and a regular expression. I wondered what part of the time was taken by Normalizer versus the regular expression, since removing all the non-ASCII characters can be done without a regex:

import java.text.Normalizer;

public class Strip {
    public static String flattenToAscii(String string) {
        StringBuilder sb = new StringBuilder(string.length());
        string = Normalizer.normalize(string, Normalizer.Form.NFD);
        for (char c : string.toCharArray()) {
            if (c <= '\u007F') sb.append(c);
        }
        return sb.toString();
    }
}

Small additional speed-ups can be obtained by writing into a char[] and not calling toCharArray(), although I'm not sure that the decrease in code clarity merits it:

public static String flattenToAscii(String string) {
    char[] out = new char[string.length()];
    string = Normalizer.normalize(string, Normalizer.Form.NFD);
    int j = 0;
    for (int i = 0, n = string.length(); i < n; ++i) {
        char c = string.charAt(i);
        if (c <= '\u007F') out[j++] = c;
    }
    return new String(out);
}

This variation has the advantage of the correctness of the one using Normalizer and some of the speed of the one using a table. On my machine, this one is about 4x faster than the accepted answer, and 6.6x to 7x slower that @virgo47's (the accepted answer is about 26x slower than @virgo47's on my machine).

How to force a checkbox and text on the same line?

It wont break if you wrap each item in a div. Check out my fiddle with the link below. I made the width of the fieldset 125px and made each item 50px wide. You'll see the label and checkbox remain side by side on a new line and don't break.

<fieldset>
<div class="item">
    <input type="checkbox" id="a">
    <label for="a">a</label>
</div>
<div class="item">
   <input type="checkbox" id="b">
<!-- depending on width, a linebreak can occur here. -->
    <label for="b">bgf bh fhg fdg hg dg gfh dfgh</label>
</div>
<div class="item">
    <input type="checkbox" id="c">
    <label for="c">c</label>
</div>
</fieldset>

http://jsfiddle.net/t5dwp7pg/1/

DataGridView - Focus a specific cell

you can set Focus to a specific Cell by setting Selected property to true

dataGridView1.Rows[rowindex].Cells[columnindex].Selected = true;

to avoid Multiple Selection just set

dataGridView1.MultiSelect = false;

What is the easiest way to remove all packages installed by pip?

pip3 freeze --local | xargs pip3 uninstall -y

The case might be that one has to run this command several times to get an empty pip3 freeze --local.

How to stop event bubbling on checkbox click

When using jQuery you do not need to call a stop function separate.

You can just return false in the event handler

This will stop the event and cancel bubbling..

Also see event.preventDefault() vs. return false

From the jQuery docs:

These handlers, therefore, may prevent the delegated handler from triggering by calling event.stopPropagation() or returning false.

How do I unload (reload) a Python module?

The accepted answer doesn't handle the from X import Y case. This code handles it and the standard import case as well:

def importOrReload(module_name, *names):
    import sys

    if module_name in sys.modules:
        reload(sys.modules[module_name])
    else:
        __import__(module_name, fromlist=names)

    for name in names:
        globals()[name] = getattr(sys.modules[module_name], name)

# use instead of: from dfly_parser import parseMessages
importOrReload("dfly_parser", "parseMessages")

In the reloading case, we reassign the top level names to the values stored in the newly reloaded module, which updates them.

JavaScript get element by name

The reason you're seeing that error is because document.getElementsByName returns a NodeList of elements. And a NodeList of elements does not have a .value property.

Use this instead:

document.getElementsByName("acc")[0].value

Change image in HTML page every few seconds

You can load the images at the beginning and change the css attributes to show every image.

var images = array();
for( url in your_urls_array ){
   var img = document.createElement( "img" );
   //here the image attributes ( width, height, position, etc )
   images.push( img );
}

function player( position )
{
  images[position-1].style.display = "none" //be careful working with the first position
  images[position].style.display = "block";
  //reset position if needed
  timer = setTimeOut( "player( position )", time );
}

Visual Studio Post Build Event - Copy to Relative Directory Location

Here is what you want to put in the project's Post-build event command line:

copy /Y "$(TargetDir)$(ProjectName).dll" "$(SolutionDir)lib\$(ProjectName).dll"

EDIT: Or if your target name is different than the Project Name.

copy /Y "$(TargetDir)$(TargetName).dll" "$(SolutionDir)lib\$(TargetName).dll"

The point of test %eax %eax

CMP subtracts the operands and sets the flags. Namely, it sets the zero flag if the difference is zero (operands are equal).

TEST sets the zero flag, ZF, when the result of the AND operation is zero. If two operands are equal, their bitwise AND is zero when both are zero. TEST also sets the sign flag, SF, when the most significant bit is set in the result, and the parity flag, PF, when the number of set bits is even.

JE [Jump if Equals] tests the zero flag and jumps if the flag is set. JE is an alias of JZ [Jump if Zero] so the disassembler cannot select one based on the opcode. JE is named such because the zero flag is set if the arguments to CMP are equal.

So,

TEST %eax, %eax
JE   400e77 <phase_1+0x23>

jumps if the %eax is zero.

Fatal error: Maximum execution time of 300 seconds exceeded

On Xampp, in php.ini you must check mysql.connect_timeout either. So, for example, change it to:

mysql.connect_timeout = 3600

That time will be always counted in seconds (so 1 hour in my example)

Alternative for <blink>

Please try this one and I guarantee that it will work

  <script type="text/javascript">
  function blink() {
  var blinks = document.getElementsByTagName('blink');
  for (var i = blinks.length - 1; i >= 0; i--) {
  var s = blinks[i];
  s.style.visibility = (s.style.visibility === 'visible') ? 'hidden' : 'visible';
}
window.setTimeout(blink, 1000);
}
if (document.addEventListener) document.addEventListener("DOMContentLoaded", blink, false);
else if (window.addEventListener) window.addEventListener("load", blink, false);
else if (window.attachEvent) window.attachEvent("onload", blink);
else window.onload = blink;

Then put this below:

<blink><center> Your text here </blink></div>

The located assembly's manifest definition does not match the assembly reference

I just found another reason why to get this error. I cleaned my GAC from all versions of a specific library and built my project with reference to specific version deployed together with the executable. When I run the project I got this exception searching for a newer version of the library.

The reason was publisher policy. When I uninstalled library's versions from GAC I forgot to uninstall publisher policy assemblies as well so instead of using my locally deployed assembly the assembly loader found publisher policy in GAC which told it to search for a newer version.

Test if something is not undefined in JavaScript

response[0] is not defined, check if it is defined and then check for its property title.

if(typeof response[0] !== 'undefined' && typeof response[0].title !== 'undefined'){
    //Do something
}

show dbs gives "Not Authorized to execute command" error

You should have started the mongod instance with access control, i.e., the --auth command line option, such as:

$ mongod --auth

Let's start the mongo shell, and create an administrator in the admin database:

$ mongo
> use admin
> db.createUser(
  {
    user: "myUserAdmin",
    pwd: "abc123",
    roles: [ { role: "userAdminAnyDatabase", db: "admin" } ]
  }
)

Now if you run command "db.stats()", or "show users", you will get error "not authorized on admin to execute command..."

> db.stats()
{
        "ok" : 0,
        "errmsg" : "not authorized on admin to execute command { dbstats: 1.0, scale: undefined }",
        "code" : 13,
        "codeName" : "Unauthorized"
}

The reason is that you still have not granted role "read" or "readWrite" to user myUserAdmin. You can do it as below:

> db.auth("myUserAdmin", "abc123")
> db.grantRolesToUser("myUserAdmin", [ { role: "read", db: "admin" } ])

Now You can verify it (Command "show users" now works):

> show users
{
        "_id" : "admin.myUserAdmin",
        "user" : "myUserAdmin",
        "db" : "admin",
        "roles" : [
                {
                        "role" : "read",
                        "db" : "admin"
                },
                {
                        "role" : "userAdminAnyDatabase",
                        "db" : "admin"
                }
        ]
}

Now if you run "db.stats()", you'll also be OK:

> db.stats()
{
        "db" : "admin",
        "collections" : 2,
        "views" : 0,
        "objects" : 3,
        "avgObjSize" : 151,
        "dataSize" : 453,
        "storageSize" : 65536,
        "numExtents" : 0,
        "indexes" : 3,
        "indexSize" : 81920,
        "ok" : 1
}

This user and role mechanism can be applied to any other databases in MongoDB as well, in addition to the admin database.

(MongoDB version 3.4.3)

How do I correct the character encoding of a file?

With vim from command line:

vim -c "set encoding=utf8" -c "set fileencoding=utf8" -c "wq" filename

Select SQL results grouped by weeks

I think this should do it..

Select 
ProductName,
WeekNumber,
sum(sale)
from
(
    SELECT 
    ProductName,
    DATEDIFF(week, '2011-05-30', date) AS WeekNumber,
    sale
    FROM table
)
GROUP BY
ProductName,
WeekNumber

Symbolicating iPhone App Crash Reports

This is simple, after searching a lot i found clear steps to symbolicate whole crash log file.

  • copy .app , crash_report and DSYM files in a folder.
  • connect the device with xcode
  • Then go to window -> select devices -> view device logs
  • Then select this device, delete all logs .
  • drag and drop your crash on device log section . it will automatically symbolicate the crash . just right click on report and export it .

happy coding,
Riyaz

Flatten list of lists

>>> lis=[[180.0], [173.8], [164.2], [156.5], [147.2], [138.2]]
>>> [x[0] for x in lis]
[180.0, 173.8, 164.2, 156.5, 147.2, 138.2]

C# Lambda expressions: Why should I use them?

Lambda expressions are a simpler syntax for anonymous delegates and can be used everywhere an anonymous delegate can be used. However, the opposite is not true; lambda expressions can be converted to expression trees which allows for a lot of the magic like LINQ to SQL.

The following is an example of a LINQ to Objects expression using anonymous delegates then lambda expressions to show how much easier on the eye they are:

// anonymous delegate
var evens = Enumerable
                .Range(1, 100)
                .Where(delegate(int x) { return (x % 2) == 0; })
                .ToList();

// lambda expression
var evens = Enumerable
                .Range(1, 100)
                .Where(x => (x % 2) == 0)
                .ToList();

Lambda expressions and anonymous delegates have an advantage over writing a separate function: they implement closures which can allow you to pass local state to the function without adding parameters to the function or creating one-time-use objects.

Expression trees are a very powerful new feature of C# 3.0 that allow an API to look at the structure of an expression instead of just getting a reference to a method that can be executed. An API just has to make a delegate parameter into an Expression<T> parameter and the compiler will generate an expression tree from a lambda instead of an anonymous delegate:

void Example(Predicate<int> aDelegate);

called like:

Example(x => x > 5);

becomes:

void Example(Expression<Predicate<int>> expressionTree);

The latter will get passed a representation of the abstract syntax tree that describes the expression x > 5. LINQ to SQL relies on this behavior to be able to turn C# expressions in to the SQL expressions desired for filtering / ordering / etc. on the server side.

How to split a data frame?

You may also want to cut the data frame into an arbitrary number of smaller dataframes. Here, we cut into two dataframes.

x = data.frame(num = 1:26, let = letters, LET = LETTERS)
set.seed(10)
split(x, sample(rep(1:2, 13)))

gives

$`1`
   num let LET
3    3   c   C
6    6   f   F
10  10   j   J
12  12   l   L
14  14   n   N
15  15   o   O
17  17   q   Q
18  18   r   R
20  20   t   T
21  21   u   U
22  22   v   V
23  23   w   W
26  26   z   Z

$`2`
   num let LET
1    1   a   A
2    2   b   B
4    4   d   D
5    5   e   E
7    7   g   G
8    8   h   H
9    9   i   I
11  11   k   K
13  13   m   M
16  16   p   P
19  19   s   S
24  24   x   X
25  25   y   Y

You can also split a data frame based upon an existing column. For example, to create three data frames based on the cyl column in mtcars:

split(mtcars,mtcars$cyl)

Error in plot.new() : figure margins too large, Scatter plot

Just run graphics.off() before plotting your data. This instruction solved my error. So, it's harmless to try it before taking a more complex solution.

How to get the size of a string in Python?

>>> s = 'abcd'
>>> len(s)
4

Changing the page title with Jquery

i use (and recommend):

$(document).attr("title", "Another Title");

and it works in IE as well this is an alias to

document.title = "Another Title";

Some will debate on wich is better, prop or attr, and since prop call DOM properties and attr Call HTML properties, i think this is actually better...

use this after the DOM Load

$(function(){
    $(document).attr("title", "Another Title");
});

hope this helps.

Difference between Grunt, NPM and Bower ( package.json vs bower.json )

Update for mid 2016:

The things are changing so fast that if it's late 2017 this answer might not be up to date anymore!

Beginners can quickly get lost in choice of build tools and workflows, but what's most up to date in 2016 is not using Bower, Grunt or Gulp at all! With help of Webpack you can do everything directly in NPM!

Don't get me wrong people use other workflows and I still use GULP in my legacy project(but slowly moving out of it), but this is how it's done in the best companies and developers working in this workflow make a LOT of money!

Look at this template it's a very up-to-date setup consisting of a mixture of the best and the latest technologies: https://github.com/coryhouse/react-slingshot

  • Webpack
  • NPM as a build tool (no Gulp, Grunt or Bower)
  • React with Redux
  • ESLint
  • the list is long. Go and explore!

Your questions:

When I want to add a package (and check in the dependency into git), where does it belong - into package.json or into bower.json

  • Everything belongs in package.json now

  • Dependencies required for build are in "devDependencies" i.e. npm install require-dir --save-dev (--save-dev updates your package.json by adding an entry to devDependencies)

  • Dependencies required for your application during runtime are in "dependencies" i.e. npm install lodash --save (--save updates your package.json by adding an entry to dependencies)

If that is the case, when should I ever install packages explicitly like that without adding them to the file that manages dependencies (apart from installing command line tools globally)?

Always. Just because of comfort. When you add a flag (--save-dev or --save) the file that manages deps (package.json) gets updated automatically. Don't waste time by editing dependencies in it manually. Shortcut for npm install --save-dev package-name is npm i -D package-name and shortcut for npm install --save package-name is npm i -S package-name

Calling a class method raises a TypeError in Python

To minimally modify your example, you could amend the code to:

class myclass(object):
        def __init__(self): # this method creates the class object.
                pass

        def average(self,a,b,c): #get the average of three numbers
                result=a+b+c
                result=result/3
                return result


mystuff=myclass()  # by default the __init__ method is then called.      
print mystuff.average(a,b,c)

Or to expand it more fully, allowing you to add other methods.

class myclass(object):
        def __init__(self,a,b,c):
                self.a=a
                self.b=b
                self.c=c
        def average(self): #get the average of three numbers
                result=self.a+self.b+self.c
                result=result/3
                return result

a=9
b=18
c=27
mystuff=myclass(a, b, c)        
print mystuff.average()

Easy way to test an LDAP User's Credentials

Authentication is done via a simple ldap_bind command that takes the users DN and the password. The user is authenticated when the bind is successfull. Usually you would get the users DN via an ldap_search based on the users uid or email-address.

Getting the users roles is something different as it is an ldap_search and depends on where and how the roles are stored in the ldap. But you might be able to retrieve the roles during the lap_search used to find the users DN.

Check if inputs are empty using jQuery

The :empty pseudo-selector is used to see if an element contains no childs, you should check the value :

$('#apply-form input').blur(function() {
     if(!this.value) { // zero-length string
            $(this).parents('p').addClass('warning');
     }
});

How do I get the offset().top value of an element without using jQuery?

You can try element[0].scrollTop, in my opinion this solution is faster.

Here you have bigger example - http://cvmlrobotics.blogspot.de/2013/03/angularjs-get-element-offset-position.html

Javascript Append Child AFTER Element

You could also do

function insertAfter(node1, node2) {
    node1.outerHTML += node2.outerHTML;
}

or

function insertAfter2(node1, node2) {
    var wrap = document.createElement("div");
    wrap.appendChild(node2.cloneNode(true));
    var node2Html = wrap.innerHTML;
    node1.insertAdjacentHTML('afterend', node2Html);
}