Programs & Examples On #Splunk

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

By default, Android Studio has a maximum heap size of 1280MB. If you are working on a large project, or your system has a lot of RAM, you can improve performance by increasing the maximum heap size for Android Studio processes, such as the core IDE, Gradle daemon, and Kotlin daemon.

If you use a 64-bit system that has at least 5 GB of RAM, you can also adjust the heap sizes for your project manually. To do so, follow these steps:

Click File > Settings from the menu bar (or Android Studio > Preferences on macOS). Click Appearance & Behavior > System Settings > Memory Settings.

For more Info click

https://developer.android.com/studio/intro/studio-config

enter image description here

Docker command can't connect to Docker daemon

For Ubuntu:
Happened with me when I updated docker.
You need to unmask the service and socket and then restart the service.

Following worked for me:

systemctl unmask docker.service
systemctl unmask docker.socket
systemctl start docker.service

What happend behind the scenes
systemd also has the ability to mark a unit as completely unstartable, automatically or manually, by linking it to /dev/null. This is called masking the unit, and is possible with the mask command.

sudo systemctl mask docker.service

You can check the list of masked services using:

sudo systemctl list-unit-files

Output of sudo systemctl list-unit-files

To enable auto/manual start of service you need to unmask it using:

sudo sytemctl unmask docker.service

Now the service will be enabled as shown below enter image description here

Android Studio says "cannot resolve symbol" but project compiles

Invalidate Caches / Restart didn't work for me this time.

Found a solution like this:

  1. Remove the compile *** or implementation *** line in build.gradle.

  2. Clean and rebuild. Errors should be raised here.

  3. Add the line in step 1 back to build.gradle.

  4. Clean and rebuild.

Weird...

How can I remove the decimal part from JavaScript number?

u can also show a certain number of digit after decimal point(here 2 digits) using following code :

_x000D_
_x000D_
var num = (15.46974).toFixed(2)_x000D_
console.log(num) // 15.47_x000D_
console.log(typeof num) // string
_x000D_
_x000D_
_x000D_

Integer division: How do you produce a double?

Just add "D".

int i = 6;
double d = i / 2D; // This will divide bei double.
System.out.println(d); // This will print a double. = 3D

WAMP Server ERROR "Forbidden You don't have permission to access /phpmyadmin/ on this server."

Go to C:\wamp\alias. Open the file phpmyadmin.conf and add

Options Indexes FollowSymLinks MultiViews
AllowOverride all
Order Deny,Allow
Deny from all
Allow from 127.0.0.1
Allow from MACHINE_IP

How can I determine if an image has loaded, using Javascript/jQuery?

I just created a jQuery function to load an image using jQuerys Deferred Object which makes it very easy to react on load/error event:

$.fn.extend({
    loadImg: function(url, timeout) {
        // init deferred object
        var defer = $.Deferred(),
            $img = this,
            img = $img.get(0),
            timer = null;

        // define load and error events BEFORE setting the src
        // otherwise IE might fire the event before listening to it
        $img.load(function(e) {
            var that = this;
            // defer this check in order to let IE catch the right image size
            window.setTimeout(function() {
                // make sure the width and height are > 0
                ((that.width > 0 && that.height > 0) ? 
                    defer.resolveWith : 
                    defer.rejectWith)($img);
            }, 1);
        }).error(function(e) {
            defer.rejectWith($img);
        });

        // start loading the image
        img.src = url;

        // check if it's already in the cache
        if (img.complete) {
            defer.resolveWith($img);
        } else if (0 !== timeout) {
            // add a timeout, by default 15 seconds
            timer = window.setTimeout(function() {
                defer.rejectWith($img);
            }, timeout || 15000);
        }

        // return the promise of the deferred object
        return defer.promise().always(function() {
            // stop the timeout timer
            window.clearTimeout(timer);
            timer = null;
            // unbind the load and error event
            this.off("load error");
        });
    }
});

Usage:

var image = $('<img />').loadImg('http://www.google.com/intl/en_com/images/srpr/logo3w.png')
.done(function() {
    alert('image loaded');
    $('body').append(this);
}).fail(function(){
    alert('image failed');
});

See it working at: http://jsfiddle.net/roberkules/AdWZj/

How to load specific image from assets with Swift

You can easily pick image from asset without UIImage(named: "green-square-Retina").

Instead use the image object directly from bundle.
Start typing the image name and you will get suggestions with actual image from bundle. It is advisable practice and less prone to error.

See this Stackoverflow answer for reference.

How to resolve the "ADB server didn't ACK" error?

if you are using any mobile suit like mobogenie or something that might also will make this issue. try killing that too from the task manager.

Note : i faced the same issue, tried the above solution. That didn't work, finally found out this solution.May useful for someone else!..

How to submit a form on enter when the textarea has focus?

Why do you want a textarea to submit when you hit enter?

A "text" input will submit by default when you press enter. It is a single line input.

<input type="text" value="...">

A "textarea" will not, as it benefits from multi-line capabilities. Submitting on enter takes away some of this benefit.

<textarea name="area"></textarea>

You can add JavaScript code to detect the enter keypress and auto-submit, but you may be better off using a text input.

Get value of a string after last slash in JavaScript

As required in Question::

var string1= "foo/bar/test.html";
  if(string1.contains("/"))
  {
      var string_parts = string1.split("/");
    var result = string_parts[string_parts.length - 1];
    console.log(result);
  }  

and for question asked on url (asked for one occurence of '=' )::
[http://stackoverflow.com/questions/24156535/how-to-split-a-string-after-a-particular-character-in-jquery][1]

var string1= "Hello how are =you";
  if(string1.contains("="))
  {
      var string_parts = string1.split("=");
    var result = string_parts[string_parts.length - 1];
    console.log(result);
  }

Python: SyntaxError: keyword can't be an expression

I guess many of us who came to this page have a problem with Scikit Learn, one way to solve it is to create a dictionary with parameters and pass it to the model:

params = {'C': 1e9, 'gamma': 1e-07}
cls = SVC(**params)    

Count number of matches of a regex in Javascript

('my string'.match(/\s/g) || []).length;

How do I change the font color in an html table?

table td{
  color:#0000ff;
}

<table>
  <tbody>
    <tr>
    <td>
      <select name="test">
        <option value="Basic">Basic : $30.00 USD - yearly</option>
        <option value="Sustaining">Sustaining : $60.00 USD - yearly</option>
        <option value="Supporting">Supporting : $120.00 USD - yearly</option>
      </select>
    </td>
    </tr>
  </tbody>
</table>

How to add a new row to datagridview programmatically

Consider a Windows Application and using Button Click Event put this code in it.

dataGridView1.Rows
                .Add(new object[] { textBox1.Text, textBox2.Text, textBox3.Text });

applying css to specific li class

The CSS you have applies color #c1c1c1 to all <a> elements.

And it also applies color #c1c1c1 to the first <li> element.

Perhaps the code you posted is missing something because I don't see any other colors being defined.

JavaScript hard refresh of current page

Try to use:

location.reload(true);

When this method receives a true value as argument, it will cause the page to always be reloaded from the server. If it is false or not specified, the browser may reload the page from its cache.

More info:

Start service in Android

startService(new Intent(this, MyService.class));

Just writing this line was not sufficient for me. Service still did not work. Everything had worked only after registering service at manifest

<application
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name" >

    ...

    <service
        android:name=".MyService"
        android:label="My Service" >
    </service>
</application>

Difference between string and StringBuilder in C#

Strings are immutable i.e if you change their value, the old value will be discarded and a new value is created on the heap, whereas in string builder we can modify the existing value without the new value being created.

So performance-wise String Builder is beneficial as we are needlessly not occupying more memory space.

What parameters should I use in a Google Maps URL to go to a lat-lon?

This is current accepted way to link to a specific lat lon (rather than search for the nearest object).

http://maps.google.com/maps?z=12&t=m&q=loc:38.9419+-78.3020
  • z is the zoom level (1-20)
  • t is the map type ("m" map, "k" satellite, "h" hybrid, "p" terrain, "e" GoogleEarth)
  • q is the search query, if it is prefixed by loc: then google assumes it is a lat lon separated by a +

How to configure Fiddler to listen to localhost?

You cannot. Instead if you machine is named "myMachine", point your browser to http://mymachine instead of http://localhost

go to character in vim

:goto 21490 will take you to the 21490th byte in the buffer.

python convert list to dictionary

Not sure whether it would help you or not but it works to me:

l = ["a", "b", "c", "d", "e"]
outRes = dict((l[i], l[i+1]) if i+1 < len(l) else (l[i], '') for i in xrange(len(l)))

What is java pojo class, java bean, normal class?

POJO = Plain Old Java Object. It has properties, getters and setters for respective properties. It may also override Object.toString() and Object.equals().

Java Beans : See Wiki link.

Normal Class : Any java Class.

Margin while printing html page

If you know the target paper size, you can place your content in a DIV with that specific size and add a margin to that DIV to simulate the print margin. Unfortunately, I don't believe you have extra control over the print functionality apart from just show the print dialog box.

How to add an extra column to a NumPy array

np.r_[ ... ] and np.c_[ ... ] are useful alternatives to vstack and hstack, with square brackets [] instead of round ().
A couple of examples:

: import numpy as np
: N = 3
: A = np.eye(N)

: np.c_[ A, np.ones(N) ]              # add a column
array([[ 1.,  0.,  0.,  1.],
       [ 0.,  1.,  0.,  1.],
       [ 0.,  0.,  1.,  1.]])

: np.c_[ np.ones(N), A, np.ones(N) ]  # or two
array([[ 1.,  1.,  0.,  0.,  1.],
       [ 1.,  0.,  1.,  0.,  1.],
       [ 1.,  0.,  0.,  1.,  1.]])

: np.r_[ A, [A[1]] ]              # add a row
array([[ 1.,  0.,  0.],
       [ 0.,  1.,  0.],
       [ 0.,  0.,  1.],
       [ 0.,  1.,  0.]])
: # not np.r_[ A, A[1] ]

: np.r_[ A[0], 1, 2, 3, A[1] ]    # mix vecs and scalars
  array([ 1.,  0.,  0.,  1.,  2.,  3.,  0.,  1.,  0.])

: np.r_[ A[0], [1, 2, 3], A[1] ]  # lists
  array([ 1.,  0.,  0.,  1.,  2.,  3.,  0.,  1.,  0.])

: np.r_[ A[0], (1, 2, 3), A[1] ]  # tuples
  array([ 1.,  0.,  0.,  1.,  2.,  3.,  0.,  1.,  0.])

: np.r_[ A[0], 1:4, A[1] ]        # same, 1:4 == arange(1,4) == 1,2,3
  array([ 1.,  0.,  0.,  1.,  2.,  3.,  0.,  1.,  0.])

(The reason for square brackets [] instead of round () is that Python expands e.g. 1:4 in square -- the wonders of overloading.)

Are members of a C++ struct initialized to 0 by default?

In C++, use no-argument constructors. In C you can't have constructors, so use either memset or - the interesting solution - designated initializers:

struct Snapshot s = { .x = 0.0, .y = 0.0 };

Jquery sortable 'change' event element position

This works for me:

start: function(event, ui) {
        var start_pos = ui.item.index();
        ui.item.data('start_pos', start_pos);
    },
update: function (event, ui) {
        var start_pos = ui.item.data('start_pos');
        var end_pos = ui.item.index();
        //$('#sortable li').removeClass('highlights');
    }

Count(*) vs Count(1) - SQL Server

If you run the following in SQL Server, you'll notice that COUNT(1) is evaluated as COUNT(*) anyway. So it appears that there is no difference, and also that COUNT(*) is the expression most native to the query optimizer:

SET SHOWPLAN_TEXT ON
GO

SELECT COUNT(1)
FROM <table>
GO

SET SHOWPLAN_TEXT OFF
GO

Bootstrap footer at the bottom of the page

In my case for Bootstrap4:

<body class="d-flex flex-column min-vh-100">
    <div class="wrapper flex-grow-1"></div>
    <footer></footer>
</body>

How to read input with multiple lines in Java

 public class Sol {

   public static void main(String[] args) {

   Scanner sc = new Scanner(System.in); 

   while(sc.hasNextLine()){

   System.out.println(sc.nextLine());

  }
 }
}

Get child node index

I've become fond of using indexOf for this. Because indexOf is on Array.prototype and parent.children is a NodeList, you have to use call(); It's kind of ugly but it's a one liner and uses functions that any javascript dev should be familiar with anyhow.

var child = document.getElementById('my_element');
var parent = child.parentNode;
// The equivalent of parent.children.indexOf(child)
var index = Array.prototype.indexOf.call(parent.children, child);

Invalid postback or callback argument. Event validation is enabled using '<pages enableEventValidation="true"/>'

If you are using gridview and not bind gridview at pageload inside !ispostback then this error occur when you click on edit and delete row in gridview .

 protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
        bindGridview();
        }

How to enter command with password for git pull?

You can just use username no need to use password since password will be prompted in git bash.

git pull https://[email protected]/username/myrepo

HTML / CSS table with GRIDLINES

Via css. Put this inside the <head> tag.

<style type="text/css" media="screen">

table{
border-collapse:collapse;
border:1px solid #FF0000;
}

table td{
border:1px solid #FF0000;
}
</style>

How to remove all files from directory without removing directory in Node.js

Yes, there is a module fs-extra. There is a method .emptyDir() inside this module which does the job. Here is an example:

const fsExtra = require('fs-extra')

fsExtra.emptyDirSync(fileDir)

There is also an asynchronous version of this module too. Anyone can check out the link.

fetch in git doesn't get all branches

This could be due to a face palm moment: if you switch between several clones it is easy to find yourself in the wrong source tree trying to pull a non-existent branch. It is easier when the clones have similar names, or the repos are distinct clones for the same project from each of multiple contributors. A new git clone would obviously seem to solve that "problem" when the real problem is losing focus or working context or both.

What is the difference between canonical name, simple name and class name in Java Class?

It is interesting to note that getCanonicalName() and getSimpleName() can raise InternalError when the class name is malformed. This happens for some non-Java JVM languages, e.g., Scala.

Consider the following (Scala 2.11 on Java 8):

scala> case class C()
defined class C

scala> val c = C()
c: C = C()

scala> c.getClass.getSimpleName
java.lang.InternalError: Malformed class name
  at java.lang.Class.getSimpleName(Class.java:1330)
  ... 32 elided

scala> c.getClass.getCanonicalName
java.lang.InternalError: Malformed class name
  at java.lang.Class.getSimpleName(Class.java:1330)
  at java.lang.Class.getCanonicalName(Class.java:1399)
  ... 32 elided

scala> c.getClass.getName
res2: String = C

This can be a problem for mixed language environments or environments that dynamically load bytecode, e.g., app servers and other platform software.

Split Div Into 2 Columns Using CSS

The most flexible way to do this:

#content::after {
  display:block;
  content:"";
  clear:both;
}

This acts exactly the same as appending the element to #content:

<br style="clear:both;"/>

but without actually adding an element. ::after is called a pseudo element. The only reason this is better than adding overflow:hidden; to #content is that you can have absolute positioned child elements overflow and still be visible. Also it will allow box-shadow's to still be visible.

retrieve data from db and display it in table in php .. see this code whats wrong with it?

Here is the solution total html with php and database connections

   <!doctype html>
    <html lang="en">
    <head>
      <meta charset="UTF-8">
      <title>database connections</title>
    </head>
    <body>
      <?php
      $username = "database-username";
      $password = "database-password";
      $host = "localhost";

      $connector = mysql_connect($host,$username,$password)
          or die("Unable to connect");
        echo "Connections are made successfully::";
      $selected = mysql_select_db("test_db", $connector)
        or die("Unable to connect");

      //execute the SQL query and return records
      $result = mysql_query("SELECT * FROM table_one ");
      ?>
      <table border="2" style= "background-color: #84ed86; color: #761a9b; margin: 0 auto;" >
      <thead>
        <tr>
          <th>Employee_id</th>
          <th>Employee_Name</th>
          <th>Employee_dob</th>
          <th>Employee_Adress</th>
          <th>Employee_dept</th>
          <td>Employee_salary</td>
        </tr>
      </thead>
      <tbody>
        <?php
          while( $row = mysql_fetch_assoc( $result ) ){
            echo
            "<tr>
              <td>{$row\['employee_id'\]}</td>
              <td>{$row\['employee_name'\]}</td>
              <td>{$row\['employee_dob'\]}</td>
              <td>{$row\['employee_addr'\]}</td>
              <td>{$row\['employee_dept'\]}</td>
              <td>{$row\['employee_sal'\]}</td> 
            </tr>\n";
          }
        ?>
      </tbody>
    </table>
     <?php mysql_close($connector); ?>
    </body>
    </html>

DISTINCT clause with WHERE

Wouldn't this work:

 SELECT email FROM table1 t1 
          where UNIQUE(SELECT * FROM table1 t2); 

What is the point of WORKDIR on Dockerfile?

Be careful where you set WORKDIR because it can affect the continuous integration flow. For example, setting it to /home/circleci/project will cause error something like .ssh or whatever is the remote circleci is doing at setup time.

Convert pandas Series to DataFrame

Series.to_frame can be used to convert a Series to DataFrame.

# The provided name (columnName) will substitute the series name
df = series.to_frame('columnName')

For example,

s = pd.Series(["a", "b", "c"], name="vals")
df = s.to_frame('newCol')
print(df)

   newCol
0    a
1    b
2    c

CodeIgniter - File upload required validation

you can use call back function, like this

  $this->form_validation->set_rules('userfile', 'Document', 'callback_file_selected_test');

    if ($this->form_validation->run() == FALSE) {
         //error
     }
    else{
           // success       
      }

function file_selected_test(){

    $this->form_validation->set_message('file_selected_test', 'Please select file.');
    if (empty($_FILES['userfile']['name'])) {
            return false;
        }else{
            return true;
        }
}

Android: How to Programmatically set the size of a Layout

You can get the actual height of called layout with this code:

public int getLayoutSize() {
// Get the layout id
    final LinearLayout root = (LinearLayout) findViewById(R.id.mainroot);
    final AtomicInteger layoutHeight = new AtomicInteger();

    root.post(new Runnable() { 
    public void run() { 
        Rect rect = new Rect(); 
        Window win = getWindow();  // Get the Window
                win.getDecorView().getWindowVisibleDisplayFrame(rect);

                // Get the height of Status Bar
                int statusBarHeight = rect.top;

                // Get the height occupied by the decoration contents 
                int contentViewTop = win.findViewById(Window.ID_ANDROID_CONTENT).getTop();

                // Calculate titleBarHeight by deducting statusBarHeight from contentViewTop  
                int titleBarHeight = contentViewTop - statusBarHeight; 
                Log.i("MY", "titleHeight = " + titleBarHeight + " statusHeight = " + statusBarHeight + " contentViewTop = " + contentViewTop); 

                // By now we got the height of titleBar & statusBar
                // Now lets get the screen size
                DisplayMetrics metrics = new DisplayMetrics();
                getWindowManager().getDefaultDisplay().getMetrics(metrics);   
                int screenHeight = metrics.heightPixels;
                int screenWidth = metrics.widthPixels;
                Log.i("MY", "Actual Screen Height = " + screenHeight + " Width = " + screenWidth);   

                // Now calculate the height that our layout can be set
                // If you know that your application doesn't have statusBar added, then don't add here also. Same applies to application bar also 
                layoutHeight.set(screenHeight - (titleBarHeight + statusBarHeight));
                Log.i("MY", "Layout Height = " + layoutHeight);   

            // Lastly, set the height of the layout       
            FrameLayout.LayoutParams rootParams = (FrameLayout.LayoutParams)root.getLayoutParams();
            rootParams.height = layoutHeight.get();
            root.setLayoutParams(rootParams);
        }
    });

return layoutHeight.get();
}

Two HTML tables side by side, centered on the page

Give your inner div a width.

EXAMPLE

Change your CSS:

<style>
#outer { text-align: center; }
#inner { text-align: left; margin: 0 auto; }
.t { float: left; }
table { border: 1px solid black; }
#clearit { clear: left; }
</style>

To this:

<style>
#outer { text-align: center; }
#inner { text-align: left; margin: 0 auto; width:500px }
.t { float: left; }
table { border: 1px solid black; }
#clearit { clear: left; }
</style>

Can I assume (bool)true == (int)1 for any C++ compiler?

I've found different compilers return different results on true. I've also found that one is almost always better off comparing a bool to a bool instead of an int. Those ints tend to change value over time as your program evolves and if you assume true as 1, you can get bitten by an unrelated change elsewhere in your code.

Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?

Just 2 things I think make it ALWAYS preferable to use a # Temp Table rather then a CTE are:

  1. You can not put a primary key on a CTE so the data being accessed by the CTE will have to traverse each one of the indexes in the CTE's tables rather then just accessing the PK or Index on the temp table.

  2. Because you can not add constraints, indexes and primary keys to a CTE they are more prone to bugs creeping in and bad data.


-onedaywhen yesterday

Here is an example where #table constraints can prevent bad data which is not the case in CTE's

DECLARE @BadData TABLE ( 
                       ThisID int
                     , ThatID int );
INSERT INTO @BadData
       ( ThisID
       , ThatID
       ) 
VALUES
       ( 1, 1 ),
       ( 1, 2 ),
       ( 2, 2 ),
       ( 1, 1 );

IF OBJECT_ID('tempdb..#This') IS NOT NULL
    DROP TABLE #This;
CREATE TABLE #This ( 
             ThisID int NOT NULL
           , ThatID int NOT NULL
                        UNIQUE(ThisID, ThatID) );
INSERT INTO #This
SELECT * FROM @BadData;
WITH This_CTE
     AS (SELECT *
           FROM @BadData)
     SELECT *
       FROM This_CTE;

Calling jQuery method from onClick attribute in HTML

you forgot to add this in your function : change to this :

<input type="button" value="ahaha"  onclick="$(this).MessageBox('msg');" />

Ruby get object keys as array

hash = {"apple" => "fruit", "carrot" => "vegetable"}
array = hash.keys   #=> ["apple", "carrot"]

it's that simple

jQuery append() - return appended elements

I think you could do something like this:

var $child = $("#parentId").append("<div></div>").children("div:last-child");

The parent #parentId is returned from the append, so add a jquery children query to it to get the last div child inserted.

$child is then the jquery wrapped child div that was added.

How to pretty print XML from the command line?

I would:

nicholas@mordor:~/flwor$ 
nicholas@mordor:~/flwor$ cat ugly.xml 


<root><foo a="b">lorem</foo><bar value="ipsum" /></root>

nicholas@mordor:~/flwor$ 
nicholas@mordor:~/flwor$ basex
BaseX 9.0.1 [Standalone]
Try 'help' to get more information.
> 
> create database pretty
Database 'pretty' created in 231.32 ms.
> 
> open pretty
Database 'pretty' was opened in 0.05 ms.
> 
> set parser xml
PARSER: xml
> 
> add ugly.xml
Resource(s) added in 161.88 ms.
> 
> xquery .
<root>
  <foo a="b">lorem</foo>
  <bar value="ipsum"/>
</root>
Query executed in 179.04 ms.
> 
> exit
Have fun.
nicholas@mordor:~/flwor$ 

if only because then it's "in" a database, and not "just" a file. Easier to work with, to my mind.

Subscribing to the belief that others have worked this problem out already. If you prefer, no doubt eXist might even be "better" at formatting xml, or as good.

You can always query the data various different ways, of course. I kept it as simple as possible. You can just use a GUI, too, but you specified console.

Why would one use nested classes in C++?

Nested classes are just like regular classes, but:

  • they have additional access restriction (as all definitions inside a class definition do),
  • they don't pollute the given namespace, e.g. global namespace. If you feel that class B is so deeply connected to class A, but the objects of A and B are not necessarily related, then you might want the class B to be only accessible via scoping the A class (it would be referred to as A::Class).

Some examples:

Publicly nesting class to put it in a scope of relevant class


Assume you want to have a class SomeSpecificCollection which would aggregate objects of class Element. You can then either:

  1. declare two classes: SomeSpecificCollection and Element - bad, because the name "Element" is general enough in order to cause a possible name clash

  2. introduce a namespace someSpecificCollection and declare classes someSpecificCollection::Collection and someSpecificCollection::Element. No risk of name clash, but can it get any more verbose?

  3. declare two global classes SomeSpecificCollection and SomeSpecificCollectionElement - which has minor drawbacks, but is probably OK.

  4. declare global class SomeSpecificCollection and class Element as its nested class. Then:

    • you don't risk any name clashes as Element is not in the global namespace,
    • in implementation of SomeSpecificCollection you refer to just Element, and everywhere else as SomeSpecificCollection::Element - which looks +- the same as 3., but more clear
    • it gets plain simple that it's "an element of a specific collection", not "a specific element of a collection"
    • it is visible that SomeSpecificCollection is also a class.

In my opinion, the last variant is definitely the most intuitive and hence best design.

Let me stress - It's not a big difference from making two global classes with more verbose names. It just a tiny little detail, but imho it makes the code more clear.

Introducing another scope inside a class scope


This is especially useful for introducing typedefs or enums. I'll just post a code example here:

class Product {
public:
    enum ProductType {
        FANCY, AWESOME, USEFUL
    };
    enum ProductBoxType {
        BOX, BAG, CRATE
    };
    Product(ProductType t, ProductBoxType b, String name);

    // the rest of the class: fields, methods
};

One then will call:

Product p(Product::FANCY, Product::BOX);

But when looking at code completion proposals for Product::, one will often get all the possible enum values (BOX, FANCY, CRATE) listed and it's easy to make a mistake here (C++0x's strongly typed enums kind of solve that, but never mind).

But if you introduce additional scope for those enums using nested classes, things could look like:

class Product {
public:
    struct ProductType {
        enum Enum { FANCY, AWESOME, USEFUL };
    };
    struct ProductBoxType {
        enum Enum { BOX, BAG, CRATE };
    };
    Product(ProductType::Enum t, ProductBoxType::Enum b, String name);

    // the rest of the class: fields, methods
};

Then the call looks like:

Product p(Product::ProductType::FANCY, Product::ProductBoxType::BOX);

Then by typing Product::ProductType:: in an IDE, one will get only the enums from the desired scope suggested. This also reduces the risk of making a mistake.

Of course this may not be needed for small classes, but if one has a lot of enums, then it makes things easier for the client programmers.

In the same way, you could "organise" a big bunch of typedefs in a template, if you ever had the need to. It's a useful pattern sometimes.

The PIMPL idiom


The PIMPL (short for Pointer to IMPLementation) is an idiom useful to remove the implementation details of a class from the header. This reduces the need of recompiling classes depending on the class' header whenever the "implementation" part of the header changes.

It's usually implemented using a nested class:

X.h:

class X {
public:
    X();
    virtual ~X();
    void publicInterface();
    void publicInterface2();
private:
    struct Impl;
    std::unique_ptr<Impl> impl;
}

X.cpp:

#include "X.h"
#include <windows.h>

struct X::Impl {
    HWND hWnd; // this field is a part of the class, but no need to include windows.h in header
    // all private fields, methods go here

    void privateMethod(HWND wnd);
    void privateMethod();
};

X::X() : impl(new Impl()) {
    // ...
}

// and the rest of definitions go here

This is particularly useful if the full class definition needs the definition of types from some external library which has a heavy or just ugly header file (take WinAPI). If you use PIMPL, then you can enclose any WinAPI-specific functionality only in .cpp and never include it in .h.

Image change every 30 seconds - loop

I agree with using frameworks for things like this, just because its easier. I hacked this up real quick, just fades an image out and then switches, also will not work in older versions of IE. But as you can see the code for the actual fade is much longer than the JQuery implementation posted by KARASZI István.

function changeImage() {
    var img = document.getElementById("img");
    img.src = images[x];
    x++;        
    if(x >= images.length) {
        x = 0;
    } 
    fadeImg(img, 100, true);
    setTimeout("changeImage()", 30000);
}

function fadeImg(el, val, fade) {
    if(fade === true) {
        val--;
    } else {
        val ++;
    }       
    if(val > 0 && val < 100) {
        el.style.opacity = val / 100;
        setTimeout(function(){ fadeImg(el, val, fade); }, 10);
    }
}

var images = [], x = 0;
images[0] = "image1.jpg";
images[1] = "image2.jpg";
images[2] = "image3.jpg";
setTimeout("changeImage()", 30000);

Declaration of Methods should be Compatible with Parent Methods in PHP

childClass::customMethod() has different arguments, or a different access level (public/private/protected) than parentClass::customMethod().

Visual Studio 2013 Install Fails: Program Compatibility Mode is on (Windows 10)

Maybe, you should try extract your file and setup after there.

I had trouble with Mount to virtual drive by ISO and the same with RAR file. But when I extract it, it work fine

Determine command line working directory when running node bin script

path.resolve('.') is also a reliable and clean option, because we almost always require('path'). It will give you absolute path of the directory from where it is called.

Finding the last index of an array

The array has a Length property that will give you the length of the array. Since the array indices are zero-based, the last item will be at Length - 1.

string[] items = GetAllItems();
string lastItem = items[items.Length - 1];
int arrayLength = array.Length;

When declaring an array in C#, the number you give is the length of the array:

string[] items = new string[5]; // five items, index ranging from 0 to 4.

Creating a mock HttpServletRequest out of a url string?

Simplest ways to mock an HttpServletRequest:

  1. Create an anonymous subclass:

    HttpServletRequest mock = new HttpServletRequest ()
    {
        private final Map<String, String[]> params = /* whatever */
    
        public Map<String, String[]> getParameterMap()
        {
            return params;
        }
    
        public String getParameter(String name)
        {
            String[] matches = params.get(name);
            if (matches == null || matches.length == 0) return null;
            return matches[0];
        }
    
        // TODO *many* methods to implement here
    };
    
  2. Use jMock, Mockito, or some other general-purpose mocking framework:

    HttpServletRequest mock = context.mock(HttpServletRequest.class); // jMock
    HttpServletRequest mock2 = Mockito.mock(HttpServletRequest.class); // Mockito
    
  3. Use HttpUnit's ServletUnit and don't mock the request at all.

Call static method with reflection

As the documentation for MethodInfo.Invoke states, the first argument is ignored for static methods so you can just pass null.

foreach (var tempClass in macroClasses)
{
   // using reflection I will be able to run the method as:
   tempClass.GetMethod("Run").Invoke(null, null);
}

As the comment points out, you may want to ensure the method is static when calling GetMethod:

tempClass.GetMethod("Run", BindingFlags.Public | BindingFlags.Static).Invoke(null, null);

Regex to match string containing two names in any order

You can do:

\bjack\b.*\bjames\b|\bjames\b.*\bjack\b

What exactly is \r in C language?

' \r ' means carriage return.

The \r means nothing special as a consequence.For character-mode terminals (typically emulating even-older printing ones as above), in raw mode, \r and \n act similarly (except both in terms of the cursor, as there is no carriage or roller . Historically a \n was used to move the carriage down, while the \r was used to move the carriage back to the left side of the screen.

How to replace � in a string

Character issues like this are difficult to diagnose because information is easily lost through misinterpretation of characters via application bugs, misconfiguration, cut'n'paste, etc.

As I (and apparently others) see it, you've pasted three characters:

codepoint   glyph   escaped    windows-1252    info
=======================================================================
U+00ef      ï       \u00ef     ef,             LATIN_1_SUPPLEMENT, LOWERCASE_LETTER
U+00bf      ¿       \u00bf     bf,             LATIN_1_SUPPLEMENT, OTHER_PUNCTUATION
U+00bd      ½       \u00bd     bd,             LATIN_1_SUPPLEMENT, OTHER_NUMBER

To identify the character, download and run the program from this page. Paste your character into the text field and select the glyph mode; paste the report into your question. It'll help people identify the problematic character.

jquery function val() is not equivalent to "$(this).value="?

Note that :

typeof $(this) is JQuery object.

and

typeof $(this)[0] is HTMLElement object

then : if you want to apply .val() on HTMLElement , you can add this extension .

HTMLElement.prototype.val=function(v){
   if(typeof v!=='undefined'){this.value=v;return this;}
   else{return this.value}
}

Then :

document.getElementById('myDiv').val() ==== $('#myDiv').val()

And

 document.getElementById('myDiv').val('newVal') ==== $('#myDiv').val('newVal')

????? INVERSE :

Conversely? if you want to add value property to jQuery object , follow those steps :

  1. Download the full source code (not minified) i.e: example http://code.jquery.com/jquery-1.11.1.js .

  2. Insert Line after L96 , add this code value:"" to init this new prop enter image description here

  3. Search on jQuery.fn.init , it will be almost Line 2747

enter image description here

  1. Now , assign a value to value prop : (Before return statment add this.value=jQuery(selector).val()) enter image description here

Enjoy now : $('#myDiv').value

How can I create a simple message box in Python?

Use

from tkinter.messagebox import *
Message([master], title="[title]", message="[message]")

The master window has to be created before. This is for Python 3. This is not fot wxPython, but for tkinter.

How do I create an .exe for a Java program?

If you really want an exe Excelsior JET is a professional level product that compiles to native code:

http://www.excelsior-usa.com/jet.html

You can also look at JSMooth:

http://jsmooth.sourceforge.net/

And if your application is compatible with its compatible with AWT/Apache classpath then GCJ compiles to native exe.

Preloading images with JavaScript

Solution for ECMAScript 2017 compliant browsers

Note: this will also work if you are using a transpiler like Babel.

'use strict';

function imageLoaded(src, alt = '') {
    return new Promise(function(resolve) {
        const image = document.createElement('img');

        image.setAttribute('alt', alt);
        image.setAttribute('src', src);

        image.addEventListener('load', function() {
            resolve(image);
        });
    });
}

async function runExample() {
    console.log("Fetching my cat's image...");

    const myCat = await imageLoaded('https://placekitten.com/500');

    console.log("My cat's image is ready! Now is the time to load my dog's image...");

    const myDog = await imageLoaded('https://placedog.net/500');

    console.log('Whoa! This is now the time to enable my galery.');

    document.body.appendChild(myCat);
    document.body.appendChild(myDog);
}

runExample();

You could also have waited for all images to load.

async function runExample() {
    const [myCat, myDog] = [
        await imageLoaded('https://placekitten.com/500'),
        await imageLoaded('https://placedog.net/500')
    ];

    document.body.appendChild(myCat);
    document.body.appendChild(myDog);
}

Or use Promise.all to load them in parallel.

async function runExample() {
    const [myCat, myDog] = await Promise.all([
        imageLoaded('https://placekitten.com/500'),
        imageLoaded('https://placedog.net/500')
    ]);

    document.body.appendChild(myCat);
    document.body.appendChild(myDog);
}

More about Promises.

More about "Async" functions.

More about the destructuring assignment.

More about ECMAScript 2015.

More about ECMAScript 2017.

HTTP GET in VBS

You haven't at time of writing described what you are going to do with the response or what its content type is. An answer already contains a very basic usage of MSXML2.XMLHTTP (I recommend the more explicit MSXML2.XMLHTTP.3.0 progID) however you may need to do different things with the response, it may not be text.

The XMLHTTP also has a responseBody property which is a byte array version of the reponse and there is a responseStream which is an IStream wrapper for the response.

Note that in a server-side requirement (e.g., VBScript hosted in ASP) you would use MSXML.ServerXMLHTTP.3.0 or WinHttp.WinHttpRequest.5.1 (which has a near identical interface).

Here is an example of using XmlHttp to fetch a PDF file and store it:-

Dim oXMLHTTP
Dim oStream

Set oXMLHTTP = CreateObject("MSXML2.XMLHTTP.3.0")

oXMLHTTP.Open "GET", "http://someserver/folder/file.pdf", False
oXMLHTTP.Send

If oXMLHTTP.Status = 200 Then
    Set oStream = CreateObject("ADODB.Stream")
    oStream.Open
    oStream.Type = 1
    oStream.Write oXMLHTTP.responseBody
    oStream.SaveToFile "c:\somefolder\file.pdf"
    oStream.Close
End If

How to dump raw RTSP stream to file?

If you are reencoding in your ffmpeg command line, that may be the reason why it is CPU intensive. You need to simply copy the streams to the single container. Since I do not have your command line I cannot suggest a specific improvement here. Your acodec and vcodec should be set to copy is all I can say.

EDIT: On seeing your command line and given you have already tried it, this is for the benefit of others who come across the same question. The command:

ffmpeg -i rtsp://@192.168.241.1:62156 -acodec copy -vcodec copy c:/abc.mp4

will not do transcoding and dump the file for you in an mp4. Of course this is assuming the streamed contents are compatible with an mp4 (which in all probability they are).

Using GregorianCalendar with SimpleDateFormat

A SimpleDateFormat, as its name indicates, formats Dates. Not a Calendar. So, if you want to format a GregorianCalendar using a SimpleDateFormat, you must convert the Calendar to a Date first:

dateFormat.format(calendar.getTime());

And what you see printed is the toString() representation of the calendar. It's intended usage is debugging. It's not intended to be used to display a date in a GUI. For that, use a (Simple)DateFormat.

Finally, to convert from a String to a Date, you should also use a (Simple)DateFormat (its parse() method), rather than splitting the String as you're doing. This will give you a Date object, and you can create a Calendar from the Date by instanciating it (Calendar.getInstance()) and setting its time (calendar.setTime()).

My advice would be: Googling is not the solution here. Reading the API documentation is what you need to do.

Javascript Get Values from Multiple Select Option Box

Also, change this:

    SelBranchVal = SelBranchVal + "," + InvForm.SelBranch[x].value;

to

    SelBranchVal = SelBranchVal + InvForm.SelBranch[x].value+ "," ;

The reason is that for the first time the variable SelBranchVal will be empty

Video auto play is not working in Safari and Chrome desktop browser

The best fix I could get was adding this code just after the </video>

<script>
    document.getElementById('vid').play();
</script>

...not pretty but somehow works.

UPDATE Recently many browsers can only autoplay the videos with sound off, so you'll need to add muted attribute to the video tag too

<video autoplay muted>
...
</video>

Android Studio Gradle: Error:Execution failed for task ':app:processDebugGoogleServices'. > No matching client found for package

For me, I had to check the google-services.json file and make sure "package_name" was correctly set to the package name of my android app. The auto generated services file had .backend appended to it in my case.

How do I revert my changes to a git submodule?

For git <= 2.13 these two commands combined should reset your repos with recursive submodules:

git submodule foreach --recursive git reset --hard
git submodule update --recursive --init

How do getters and setters work?

1. The best getters / setters are smart.

Here's a javascript example from mozilla:

var o = { a:0 } // `o` is now a basic object

Object.defineProperty(o, "b", { 
    get: function () { 
        return this.a + 1; 
    } 
});

console.log(o.b) // Runs the getter, which yields a + 1 (which is 1)

I've used these A LOT because they are awesome. I would use it when getting fancy with my coding + animation. For example, make a setter that deals with an Number which displays that number on your webpage. When the setter is used it animates the old number to the new number using a tweener. If the initial number is 0 and you set it to 10 then you would see the numbers flip quickly from 0 to 10 over, let's say, half a second. Users love this stuff and it's fun to create.

2. Getters / setters in php

Example from sof

<?php
class MyClass {
  private $firstField;
  private $secondField;

  public function __get($property) {
    if (property_exists($this, $property)) {
      return $this->$property;
    }
  }

  public function __set($property, $value) {
    if (property_exists($this, $property)) {
      $this->$property = $value;
    }

    return $this;
  }
}
?>

citings:

How to properly use jsPDF library

According to the latest version (1.5.3) there is no fromHTML() method anymore. Instead you should utilize jsPDF HTML plugin, see: https://rawgit.com/MrRio/jsPDF/master/docs/module-html.html#~html

You also need to add html2canvas library in order for it to work properly: https://github.com/niklasvh/html2canvas

JS (from API docs):

var doc = new jsPDF();   

doc.html(document.body, {
   callback: function (doc) {
     doc.save();
   }
});

You can provide HTML string instead of reference to the DOM element as well.

Passing base64 encoded strings in URL

In theory, yes, as long as you don't exceed the maximum url and/oor query string length for the client or server.

In practice, things can get a bit trickier. For example, it can trigger an HttpRequestValidationException on ASP.NET if the value happens to contain an "on" and you leave in the trailing "==".

How can I get the average (mean) of selected columns

Try using rowMeans:

z$mean=rowMeans(z[,c("x", "y")], na.rm=TRUE)

  w x  y mean
1 5 1  1    1
2 6 2  2    2
3 7 3  3    3
4 8 4 NA    4

Pretty Printing JSON with React

const getJsonIndented = (obj) => JSON.stringify(newObj, null, 4).replace(/["{[,\}\]]/g, "")

const JSONDisplayer = ({children}) => (
    <div>
        <pre>{getJsonIndented(children)}</pre>
    </div>
)

Then you can easily use it:

const Demo = (props) => {
   ....
   return <JSONDisplayer>{someObj}<JSONDisplayer>
}

How to specify the download location with wget?

Make sure you have the URL correct for whatever you are downloading. First of all, URLs with characters like ? and such cannot be parsed and resolved. This will confuse the cmd line and accept any characters that aren't resolved into the source URL name as the file name you are downloading into.

For example:

wget "sourceforge.net/projects/ebosse/files/latest/download?source=typ_redirect"

will download into a file named, ?source=typ_redirect.

As you can see, knowing a thing or two about URLs helps to understand wget.

I am booting from a hirens disk and only had Linux 2.6.1 as a resource (import os is unavailable). The correct syntax that solved my problem downloading an ISO onto the physical hard drive was:

wget "(source url)" -O (directory where HD was mounted)/isofile.iso" 

One could figure the correct URL by finding at what point wget downloads into a file named index.html (the default file), and has the correct size/other attributes of the file you need shown by the following command:

wget "(source url)"

Once that URL and source file is correct and it is downloading into index.html, you can stop the download (ctrl + z) and change the output file by using:

-O "<specified download directory>/filename.extension"

after the source url.

In my case this results in downloading an ISO and storing it as a binary file under isofile.iso, which hopefully mounts.

How to delete from a text file, all lines that contain a specific string?

Delete lines from all files that match the match

grep -rl 'text_to_search' . | xargs sed -i '/text_to_search/d'

The permissions granted to user ' are insufficient for performing this operation. (rsAccessDenied)"}

You can also make sure that the Identity in your Application Pool has the right permissions.

  1. Go to IIS Manager

  2. Click Application pools

  3. Identify the application pool of the site you are deploying reports on

  4. Check that the identity is set to some service account or user account that has admin permissions

  5. You can change the identity by stopping the pool, right clicking it, and selecting Advanced Settings...

Under Process Model is the Identity field

How to concatenate strings in windows batch file for loop?

Try this, with strings:

set "var=string1string2string3"

and with string variables:

set "var=%string1%%string2%%string3%"

How to parse XML and count instances of a particular node attribute?

Here a very simple but effective code using cElementTree.

try:
    import cElementTree as ET
except ImportError:
  try:
    # Python 2.5 need to import a different module
    import xml.etree.cElementTree as ET
  except ImportError:
    exit_err("Failed to import cElementTree from any known place")      

def find_in_tree(tree, node):
    found = tree.find(node)
    if found == None:
        print "No %s in file" % node
        found = []
    return found  

# Parse a xml file (specify the path)
def_file = "xml_file_name.xml"
try:
    dom = ET.parse(open(def_file, "r"))
    root = dom.getroot()
except:
    exit_err("Unable to open and parse input definition file: " + def_file)

# Parse to find the child nodes list of node 'myNode'
fwdefs = find_in_tree(root,"myNode")

This is from "python xml parse".

How to parse JSON boolean value?

You can cast this value to a Boolean in a very simple manner: by comparing it with integer value 1, like this:

boolean multipleContacts = new Integer(1).equals(jsonObject.get("MultipleContacts"))

If it is a String, you could do this:

boolean multipleContacts = "1".equals(jsonObject.get("MultipleContacts"))

How do I use System.getProperty("line.separator").toString()?

The problem

You must NOT assume that an arbitrary input text file uses the "correct" platform-specific newline separator. This seems to be the source of your problem; it has little to do with regex.

To illustrate, on the Windows platform, System.getProperty("line.separator") is "\r\n" (CR+LF). However, when you run your Java code on this platform, you may very well have to deal with an input file whose line separator is simply "\n" (LF). Maybe this file was originally created in Unix platform, and then transferred in binary (instead of text) mode to Windows. There could be many scenarios where you may run into these kinds of situations, where you must parse a text file as input which does not use the current platform's newline separator.

(Coincidentally, when a Windows text file is transferred to Unix in binary mode, many editors would display ^M which confused some people who didn't understand what was going on).

When you are producing a text file as output, you should probably prefer the platform-specific newline separator, but when you are consuming a text file as input, it's probably not safe to make the assumption that it correctly uses the platform specific newline separator.


The solution

One way to solve the problem is to use e.g. java.util.Scanner. It has a nextLine() method that can return the next line (if one exists), correctly handling any inconsistency between the platform's newline separator and the input text file.

You can also combine 2 Scanner, one to scan the file line by line, and another to scan the tokens of each line. Here's a simple usage example that breaks each line into a List<String>. The entire file therefore becomes a List<List<String>>.

This is probably a better approach than reading the entire file into one huge String and then split into lines (which are then split into parts).

    String text
        = "row1\tblah\tblah\tblah\n"
        + "row2\t1\t2\t3\t4\r\n"
        + "row3\tA\tB\tC\r"
        + "row4";

    System.out.println(text);
    //  row1    blah    blah    blah
    //  row2    1   2   3   4
    //  row3    A   B   C
    //  row4

    List<List<String>> input = new ArrayList<List<String>>();

    Scanner sc = new Scanner(text);
    while (sc.hasNextLine()) {
        Scanner lineSc = new Scanner(sc.nextLine()).useDelimiter("\t");
        List<String> line = new ArrayList<String>();
        while (lineSc.hasNext()) {
            line.add(lineSc.next());
        }
        input.add(line);
    }
    System.out.println(input);
    // [[row1, blah, blah, blah], [row2, 1, 2, 3, 4], [row3, A, B, C], [row4]]

See also

  • Effective Java 2nd Edition, Item 25: Prefer lists to arrays

Related questions

Practical uses for the "internal" keyword in C#

Internal classes enable you to limit the API of your assembly. This has benefits, like making your API simpler to understand.

Also, if a bug exists in your assembly, there is less of a chance of the fix introducing a breaking change. Without internal classes, you would have to assume that changing any class's public members would be a breaking change. With internal classes, you can assume that modifying their public members only breaks the internal API of the assembly (and any assemblies referenced in the InternalsVisibleTo attribute).

I like having encapsulation at the class level and at the assembly level. There are some who disagree with this, but it's nice to know that the functionality is available.

Setting a divs background image to fit its size?

Use this as it can also act as responsive. :

background-size: cover;

How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly?

If you want to filter rows by a certain number of columns with null values, you may use this:

df.iloc[df[(df.isnull().sum(axis=1) >= qty_of_nuls)].index]

So, here is the example:

Your dataframe:

>>> df = pd.DataFrame([range(4), [0, np.NaN, 0, np.NaN], [0, 0, np.NaN, 0], range(4), [np.NaN, 0, np.NaN, np.NaN]])
>>> df
     0    1    2    3
0  0.0  1.0  2.0  3.0
1  0.0  NaN  0.0  NaN
2  0.0  0.0  NaN  0.0
3  0.0  1.0  2.0  3.0
4  NaN  0.0  NaN  NaN

If you want to select the rows that have two or more columns with null value, you run the following:

>>> qty_of_nuls = 2
>>> df.iloc[df[(df.isnull().sum(axis=1) >=qty_of_nuls)].index]
     0    1    2   3
1  0.0  NaN  0.0 NaN
4  NaN  0.0  NaN NaN

ITextSharp insert text to an existing pdf

This worked for me and includes using OutputStream:

PdfReader reader = new PdfReader(new RandomAccessFileOrArray(Request.MapPath("Template.pdf")), null);
    Rectangle size = reader.GetPageSizeWithRotation(1);
    using (Stream outStream = Response.OutputStream)
    {
        Document document = new Document(size);
        PdfWriter writer = PdfWriter.GetInstance(document, outStream);

        document.Open();
        try
        {
            PdfContentByte cb = writer.DirectContent;

            cb.BeginText();
            try
            {
                cb.SetFontAndSize(BaseFont.CreateFont(), 12);
                cb.SetTextMatrix(110, 110);
                cb.ShowText("aaa");
            }
            finally
            {
                cb.EndText();
            }

                PdfImportedPage page = writer.GetImportedPage(reader, 1);
                cb.AddTemplate(page, 0, 0);

        }
        finally
        {
            document.Close();
            writer.Close();
            reader.Close();
        }
    }

"Please try running this command again as Root/Administrator" error when trying to install LESS

I was getting this issue for instaling expo cli and I fixed by just following four steps mentioned in the npm documentation here.

Problem is some version of npm fail to locate folder for global installations of package. Following these steps we can create or modify the .profile file in Home directory of user and give it a proper PATH there so it works like a charm.

Try this it helped me and I spent around an hour for this issue. My node version was 6.0

Steps I follow

Back up your computer. On the command line, in your home directory, create a directory for global installations:

mkdir ~/.npm-global

Configure npm to use the new directory path:

npm config set prefix '~/.npm-global'

In your preferred text editor, open or create a ~/.profile file and add this line:

export PATH=~/.npm-global/bin:$PATH

On the command line, update your system variables:

source ~/.profile

To test your new configuration, install a package globally without using sudo:

npm install -g jshint

Removing input background colour for Chrome autocomplete?

Try this: Same as @Nathan-white answer above with minor tweaks.

/* For removing autocomplete highlight color in chrome (note: use this at bottom of your css file). */

input:-webkit-autofill,
input:-webkit-autofill:hover,
input:-webkit-autofill:focus,
input:-webkit-autofill:active {
    transition: all 5000s ease-in-out 0s;
    transition-property: background-color, color;
}

Return row number(s) for a particular value in a column in a dataframe

Use which(mydata_2$height_chad1 == 2585)

Short example

df <- data.frame(x = c(1,1,2,3,4,5,6,3),
                 y = c(5,4,6,7,8,3,2,4))
df
  x y
1 1 5
2 1 4
3 2 6
4 3 7
5 4 8
6 5 3
7 6 2
8 3 4

which(df$x == 3)
[1] 4 8

length(which(df$x == 3))
[1] 2

count(df, vars = "x")
  x freq
1 1    2
2 2    1
3 3    2
4 4    1
5 5    1
6 6    1

df[which(df$x == 3),]
  x y
4 3 7
8 3 4

As Matt Weller pointed out, you can use the length function. The count function in plyr can be used to return the count of each unique column value.

Update TensorFlow

Before trying to update tensorflow try updating pip

pip install --upgrade pip

If you are upgrading from a previous installation of TensorFlow < 0.7.1, you should uninstall the previous TensorFlow and protobuf using,

pip uninstall tensorflow

to make sure you get a clean installation of the updated protobuf dependency.

Uninstall the TensorFlow on your system, and check out Download and Setup to reinstall again.

If you are using pip install, go check the available version over https://storage.googleapis.com/tensorflow, search keywords with linux/cpu/tensorflow to see the availabilities.

Then, set the path for download and execute in sudo.

$ export TF_BINARY_URL=https://storage.googleapis.com/tensorflow/linux/cpu/tensorflow-1.0.0-py2-none-any.whl

$ sudo pip install --upgrade $TF_BINARY_URL

For more detail, follow this link in here

Intercept page exit event

Similar to Ghommey's answer, but this also supports old versions of IE and Firefox.

window.onbeforeunload = function (e) {
  var message = "Your confirmation message goes here.",
  e = e || window.event;
  // For IE and Firefox
  if (e) {
    e.returnValue = message;
  }

  // For Safari
  return message;
};

How can I do GUI programming in C?

This is guaranteed to have nothing to do with the compiler. All compilers do is compile the code that they are given. What you're looking for is a GUI library, which you can write code against using any compiler that you want.

Of course, that being said, your first order of business should be to ditch Turbo C. That compiler is about 20 years old and continuing to use it isn't doing you any favors. You can't write modern GUI applications, as it will only produce 16-bit code. All modern operating systems are 32-bit, and many are now 64-bit. It's also worth noting that 64-bit editions of Windows will not run 16-bit applications natively. You'll need an emulator for that; it's not really going to engender much feeling of accomplishment if you can only write apps that work in a DOS emulator. :-)

Microsoft's Visual Studio Express C++ is available as a free download. It includes the same compiler available in the full version of the suite. The C++ package also compiles pure C code.

And since you're working in Windows, the Windows API is a natural choice. It allows you to write native Windows applications that have access to the full set of GUI controls. You'll find a nice tutorial here on writing WinAPI applications in C. If you choose to go with Visual Studio, it also includes boilerplate code for a blank WinAPI application that will get you up and running quickly.

If you really care about learning to do this, Charles Petzold's Programming Windows is the canonical resource of the subject, and definitely worth a read. The entire Windows API was written in C, and it's entirely possible to write full-featured Windows applications in C. You don't need no stinkin' C++.

That's the way I'd do it, at least. As the other answers suggest, GTK is also an option. But the applications it generates are just downright horrible-looking on Windows.


EDIT: Oh dear... It looks like you're not alone in wanting to write "GUI" applications using an antiquated compiler. A Google search turns up the following library: TurboGUI: A GUI Framework for Turbo C/C++:

 TurboGUI interface sample

If you're another one of those poor people stuck in the hopelessly out-of-date Indian school system and forced to use Turbo C to complete your education, this might be an option. I'm loathe to recommend it, as learning to work around its limitations will be completely useless to you once you graduate, but apparently it's out there for you if you're interested.

Replacing few values in a pandas dataframe column with another value

This solution will change the existing dataframe itself:

mydf = pd.DataFrame({"BrandName":["A", "B", "ABC", "D", "AB"], "Speciality":["H", "I", "J", "K", "L"]})
mydf["BrandName"].replace(["ABC", "AB"], "A", inplace=True)

Please add a @Pipe/@Directive/@Component annotation. Error

I faced the same error when I used another class instead of component down the component decorator.

Component class must come just after the component decorator

  @Component({
 selector: 'app-smsgtrecon',
 templateUrl: './smsgtrecon.component.html',
 styleUrls: ['./smsgtrecon.component.css'],
 providers: [ChecklistDatabase]
 })


// THIS CAUSE ISSUE MOVE THIS UP TO COMPONENT DECORATOR
/**
* Node for to-do item
*/
 export class TodoItemNode {
 children: TodoItemNode[];
 item: string;
}


 export class SmsgtreconComponent implements OnInit {

After moving TodoItemNode to the top of component decorator it worked

Solution

// THIS CAUSE ISSUE MOVE THIS UP TO COMPONENT DECORATOR
/**
* Node for to-do item
*/
 export class TodoItemNode {
 children: TodoItemNode[];
 item: string;
}


@Component({
 selector: 'app-smsgtrecon',
 templateUrl: './smsgtrecon.component.html',
 styleUrls: ['./smsgtrecon.component.css'],
 providers: [ChecklistDatabase]
 })


 export class SmsgtreconComponent implements OnInit {

How can I determine whether a specific file is open in Windows?

Use Process Explorer from the Sysinternals Suite, the Find Handle or DLL function will let you search for the process with that file open.

Programmatically add new column to DataGridView

Here's a sample method that adds two extra columns programmatically to the grid view:

    private void AddColumnsProgrammatically()
    {
        // I created these columns at function scope but if you want to access 
        // easily from other parts of your class, just move them to class scope.
        // E.g. Declare them outside of the function...
        var col3 = new DataGridViewTextBoxColumn();
        var col4 = new DataGridViewCheckBoxColumn();

        col3.HeaderText = "Column3";
        col3.Name = "Column3";

        col4.HeaderText = "Column4";
        col4.Name = "Column4";

        dataGridView1.Columns.AddRange(new DataGridViewColumn[] {col3,col4});
    }

A great way to figure out how to do this kind of process is to create a form, add a grid view control and add some columns. (This process will actually work for ANY kind of form control. All instantiation and initialization happens in the Designer.) Then examine the form's Designer.cs file to see how the construction takes place. (Visual Studio does everything programmatically but hides it in the Form Designer.)

For this example I created two columns for the view named Column1 and Column2 and then searched Form1.Designer.cs for Column1 to see everywhere it was referenced. The following information is what I gleaned and, copied and modified to create two more columns dynamically:

// Note that this info scattered throughout the designer but can easily collected.

        System.Windows.Forms.DataGridViewTextBoxColumn Column1;
        System.Windows.Forms.DataGridViewCheckBoxColumn Column2;

        this.Column1 = new System.Windows.Forms.DataGridViewTextBoxColumn();
        this.Column2 = new System.Windows.Forms.DataGridViewCheckBoxColumn();

        this.dataGridView1.Columns.AddRange(new System.Windows.Forms.DataGridViewColumn[] {
        this.Column1,
        this.Column2});

        this.Column1.HeaderText = "Column1";
        this.Column1.Name = "Column1";

        this.Column2.HeaderText = "Column2";
        this.Column2.Name = "Column2";

Android Fragment onClick button Method

Another option may be to have your fragment implement View.OnClickListener and override onClick(View v) within your fragment. If you need to have your fragment talk to the activity simply add an interface with desired method(s) and have the activity implement the interface and override its method(s).

public class FragName extends Fragment implements View.OnClickListener { 
    public FragmentCommunicator fComm;
    public ImageButton res1, res2;
    int c;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_test, container, false);
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        try {
            fComm = (FragmentCommunicator) activity;
        } catch (ClassCastException e) {
            throw new ClassCastException(activity.toString()
                    + " must implement FragmentCommunicator");
        }
    }

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        res1 = (ImageButton) getActivity().findViewById(R.id.responseButton1);
        res1.setOnClickListener(this);
        res2 = (ImageButton) getActivity().findViewById(R.id.responseButton2);
        res2.setOnClickListener(this);
    }
    public void onClick(final View v) { //check for what button is pressed
            switch (v.getId()) {
                case R.id.responseButton1:
                  c *= fComm.fragmentContactActivity(2);
                  break;
                case R.id.responseButton2:
                  c *= fComm.fragmentContactActivity(4);
                  break;
                default:
                  c *= fComm.fragmentContactActivity(100);
                  break;
    }
    public interface FragmentCommunicator{
        public int fragmentContactActivity(int b);
    }



public class MainActivity extends FragmentActivity implements FragName.FragmentCommunicator{
    int a = 10;
    //variable a is update by fragment. ex. use to change textview or whatever else you'd like.

    public int fragmentContactActivity(int b) {
        //update info on activity here
        a += b;
        return a;
    }
}

http://developer.android.com/training/basics/firstapp/starting-activity.html http://developer.android.com/training/basics/fragments/communicating.html

Angular 2 change event on every keypress

The (keyup) event is your best bet.

Let's see why:

  1. (change) like you mentioned triggers only when the input loses focus, hence is of limited use.
  2. (keypress) triggers on key presses but doesn't trigger on certain keystrokes like the backspace.
  3. (keydown) triggers every time a key is pushed down. Hence always lags by 1 character; as it gets the element state before the keystroke was registered.
  4. (keyup) is your best bet as it triggers every time a key push event has completed, hence this also includes the most recent character.

So (keyup) is the safest to go with because it...

  • registers an event on every keystroke unlike (change) event
  • includes the keys that (keypress) ignores
  • has no lag unlike the (keydown) event

PHP Pass by reference in foreach

Because on the second loop, $v is still a reference to the last array item, so it's overwritten each time.

You can see it like that:

$a = array ('zero','one','two', 'three');

foreach ($a as &$v) {

}

foreach ($a as $v) {
  echo $v.'-'.$a[3].PHP_EOL;
}

As you can see, the last array item takes the current loop value: 'zero', 'one', 'two', and then it's just 'two'... : )

pandas python how to count the number of records or rows in a dataframe

Regards to your question... counting one Field? I decided to make it a question, but I hope it helps...

Say I have the following DataFrame

import numpy as np
import pandas as pd

df = pd.DataFrame(np.random.normal(0, 1, (5, 2)), columns=["A", "B"])

You could count a single column by

df.A.count()
#or
df['A'].count()

both evaluate to 5.

The cool thing (or one of many w.r.t. pandas) is that if you have NA values, count takes that into consideration.

So if I did

df['A'][1::2] = np.NAN
df.count()

The result would be

 A    3
 B    5

CASE in WHERE, SQL Server

(something else) should be a.Country

if Country is nullable then make(something else) be a.Country OR a.Country is NULL

How return error message in spring mvc @Controller

return new ResponseEntity<>(GenericResponseBean.newGenericError("Error during the calling the service", -1L), HttpStatus.EXPECTATION_FAILED);

Removing all unused references from a project in Visual Studio projects

For anybody coming here looking for Visual studio 2012:

Download and Install Reference Assistant for Visual Studio 11

Later you can do:

enter image description here

Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException:

Use component scanning as given below, if com.project.action.PasswordHintAction is annotated with stereotype annotations

<context:component-scan base-package="com.project.action"/>

EDIT

I see your problem, in PasswordHintActionTest you are autowiring PasswordHintAction. But you did not create bean configuration for PasswordHintAction to autowire. Add one of stereotype annotation(@Component, @Service, @Controller) to PasswordHintAction like

@Component
public class PasswordHintAction extends BaseAction {
    private static final long serialVersionUID = -4037514607101222025L;
    private String username;

or create xml configuration in applicationcontext.xml like

<bean id="passwordHintAction" class="com.project.action.PasswordHintAction" />

Using Bootstrap Modal window as PartialView

I do this with mustache.js and templates (you could use any JavaScript templating library).

In my view, I have something like this:

<script type="text/x-mustache-template" id="modalTemplate">
    <%Html.RenderPartial("Modal");%>
</script>

...which lets me keep my templates in a partial view called Modal.ascx:

<%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl" %>
    <div>
        <div class="modal-header">
            <a class="close" data-dismiss="modal">&times;</a>
            <h3>{{Name}}</h3>
        </div>
        <div class="modal-body">
            <table class="table table-striped table-condensed">
                <tbody>
                    <tr><td>ID</td><td>{{Id}}</td></tr>
                    <tr><td>Name</td><td>{{Name}}</td></tr>
                </tbody>
            </table>
        </div>
        <div class="modal-footer">
            <a class="btn" data-dismiss="modal">Close</a>
        </div>
    </div>

I create placeholders for each modal in my view:

<%foreach (var item in Model) {%>
    <div data-id="<%=Html.Encode(item.Id)%>"
         id="modelModal<%=Html.Encode(item.Id)%>" 
         class="modal hide fade">
    </div>
<%}%>

...and make ajax calls with jQuery:

<script type="text/javascript">
    var modalTemplate = $("#modalTemplate").html()
    $(".modal[data-id]").each(function() {
        var $this = $(this)
        var id = $this.attr("data-id")
        $this.on("show", function() {
            if ($this.html()) return
            $.ajax({
                type: "POST",
                url: "<%=Url.Action("SomeAction")%>",
                data: { id: id },
                success: function(data) {
                    $this.append(Mustache.to_html(modalTemplate, data))
                }
            })
        })
    })
</script>

Then, you just need a trigger somewhere:

<%foreach (var item in Model) {%>
    <a data-toggle="modal" href="#modelModal<%=Html.Encode(item.Id)%>">
        <%=Html.Encode(item.DutModel.Name)%>
    </a>
<%}%>

Create a .txt file if doesn't exist, and if it does append a new line

using(var tw = new StreamWriter(path, File.Exists(path)))
{
    tw.WriteLine(message);
}

How do I trim leading/trailing whitespace in a standard way?

void trim(char* const str)
{
    char* begin = str;
    char* end = str;
    while (isspace(*begin))
    {
        ++begin;
    }
    char* s = begin;
    while (*s != '\0')
    {
        if (!isspace(*s++))
        {
            end = s;
        }
    }
    *end = '\0';
    const int dist = end - begin;
    if (begin > str && dist > 0)
    {
        memmove(str, begin, dist + 1);
    }
}

Modifies string in place, so you can still delete it.

Doesn't use fancy pants library functions (unless you consider memmove fancy).

Handles string overlap.

Trims front and back (not middle, sorry).

Fast if string is large (memmove often written in assembly).

Only moves characters if required (I find this true in most use cases because strings rarely have leading spaces and often don't have tailing spaces)

I would like to test this but I'm running late. Enjoy finding bugs... :-)

How to "wait" a Thread in Android

Don't use wait(), use either android.os.SystemClock.sleep(1000); or Thread.sleep(1000);.

The main difference between them is that Thread.sleep() can be interrupted early -- you'll be told, but it's still not the full second. The android.os call will not wake early.

Updating an object with setState in React

You can try with this: (Note: name of input tag === field of object)

<input name="myField" type="text" 
      value={this.state.myObject.myField} 
     onChange={this.handleChangeInpForm}>
</input>

-----------------------------------------------------------
handleChangeInpForm = (e) => {
   let newObject = this.state.myObject;
   newObject[e.target.name] = e.target.value;
   this.setState({
     myObject: newObject 
   })
}

select2 onchange event only works once

This is due because of the items id being the same. On change fires only if a different item id is detected on select.

So you have 2 options: First is to make sure that each items have a unique id when retrieving datas from ajax.

Second is to trigger a rand number at formatSelection for the selected item.

function getRandomInt(min, max) {
    return Math.floor(Math.random() * (max - min + 1)) + min;
}

.

formatSelection: function(item) {item.id =getRandomInt(1,200)}

Calculate logarithm in python

The math.log function is to the base e, i.e. natural logarithm. If you want to the base 10 use math.log10.

Best way to do Version Control for MS Excel

Use any of the standard version control tools like SVN or CVS. Limitations would depend on whats the objective. Apart from a small increase in size of the repository, i did'nt face any issues

Difference between chr(13) and chr(10)

Chr(10) is the Line Feed character and Chr(13) is the Carriage Return character.

You probably won't notice a difference if you use only one or the other, but you might find yourself in a situation where the output doesn't show properly with only one or the other. So it's safer to include both.


Historically, Line Feed would move down a line but not return to column 1:

This  
    is  
        a  
            test.

Similarly Carriage Return would return to column 1 but not move down a line:

This  
is  
a  
test.

Paste this into a text editor and then choose to "show all characters", and you'll see both characters present at the end of each line. Better safe than sorry.

Adjusting the Xcode iPhone simulator scale and size

With Xcode 9 - Simulator, you can pick & drag any corner of simulator to resize it and set according to your requirement.

Look at this snapshot.

enter image description here


Note: With Xcode 9.1+, Simulator scale options are changed.


Keyboard short-keys:
According to Xcode 9.1+

Physical Size       ? 1      command + 1
Pixel Accurate      ? 2      command + 2


According to Xcode 9

50% Scale           ? 1      command + 1
100% Scale          ? 2      command + 2
200% Scale          ? 3      command + 3

Simulator scale options from Xcode Menu:

Xcode 9.1+:
Menubar ? Window ? "Here, options available change simulator scale" (Physical Size & Pixel Accurate)

Pixel Accurate: Resizes your simulator to actual (Physical) device's pixels, if your mac system display screen size (pixel) supports that much high resolution, else this option will remain disabled.

Tip: rotate simulator ( ? + ? or ? + ? ), if Pixel Accurate is disabled. It may be enabled (if it fits to screen) in landscape.

enter image description here


Xcode 9.0
Menubar ? Window ? Scale ? "Here, options available change simulator scale"

enter image description here


Tip: How do you get screen shot with 100% (a scale with actual device size) that can be uploaded on AppStore?

Disable 'Optimize Rendering for Window scale' from Debug menu, before you take a screen shot (See here: How to take screenshots in the iOS simulator)

There is an option

Menubar ? Debug ? Disable "Optimize Rendering for Window scale"

enter image description here


Here is Apple's document: Resize a simulator window

CodeIgniter - accessing $config variable in view

Whenever I need to access config variables I tend to use: $this->config->config['variable_name'];

How to align a div inside td element using CSS class

div { margin: auto; }

This will center your div.

Div by itself is a blockelement. Therefor you need to define the style to the div how to behave.

How to send email using simple SMTP commands via Gmail?

Unfortunately as I am forced to use a windows server I have been unable to get openssl working in the way the above answer suggests.

However I was able to get a similar program called stunnel (which can be downloaded from here) to work. I got the idea from www.tech-and-dev.com but I had to change the instructions slightly. Here is what I did:

  1. Install telnet client on the windows box.
  2. Download stunnel. (I downloaded and installed a file called stunnel-4.56-installer.exe).
  3. Once installed you then needed to locate the stunnel.conf config file, which in my case I installed to C:\Program Files (x86)\stunnel
  4. Then, you need to open this file in a text viewer such as notepad. Look for [gmail-smtp] and remove the semicolon on the client line below (in the stunnel.conf file, every line that starts with a semicolon is a comment). You should end up with something like:

    [gmail-smtp]
    client = yes
    accept = 127.0.0.1:25
    connect = smtp.gmail.com:465
    

    Once you have done this save the stunnel.conf file and reload the config (to do this use the stunnel GUI program, and click on configuration=>Reload).

Now you should be ready to send email in the windows telnet client!
Go to Start=>run=>cmd.

Once cmd is open type in the following and press Enter:

telnet localhost 25

You should then see something similar to the following:

220 mx.google.com ESMTP f14sm1400408wbe.2

You will then need to reply by typing the following and pressing enter:

helo google

This should give you the following response:

250 mx.google.com at your service

If you get this you then need to type the following and press enter:

ehlo google

This should then give you the following response:

250-mx.google.com at your service, [212.28.228.49]
250-SIZE 35651584
250-8BITMIME
250-AUTH LOGIN PLAIN XOAUTH
250 ENHANCEDSTATUSCODES

Now you should be ready to authenticate with your Gmail details. To do this type the following and press enter:

AUTH LOGIN

This should then give you the following response:

334 VXNlcm5hbWU6

This means that we are ready to authenticate by using our gmail address and password.

However since this is an encrypted session, we're going to have to send the email and password encoded in base64. To encode your email and password, you can use a converter program or an online website to encode it (for example base64 or search on google for ’base64 online encoding’). I reccomend you do not touch the cmd/telnet session again until you have done this.

For example [email protected] would become dGVzdEBnbWFpbC5jb20= and password would become cGFzc3dvcmQ=

Once you have done this copy and paste your converted base64 username into the cmd/telnet session and press enter. This should give you following response:

334 UGFzc3dvcmQ6

Now copy and paste your converted base64 password into the cmd/telnet session and press enter. This should give you following response if both login credentials are correct:

235 2.7.0 Accepted

You should now enter the sender email (should be the same as the username) in the following format and press enter:

MAIL FROM:<[email protected]>

This should give you the following response:

250 2.1.0 OK x23sm1104292weq.10

You can now enter the recipient email address in a similar format and press enter:

RCPT TO:<[email protected]>

This should give you the following response:

250 2.1.5 OK x23sm1104292weq.10

Now you will need to type the following and press enter:

DATA

Which should give you the following response:

354  Go ahead x23sm1104292weq.10

Now we can start to compose the message! To do this enter your message in the following format (Tip: do this in notepad and copy the entire message into the cmd/telnet session):

From: Test <[email protected]>
To: Me <[email protected]>
Subject: Testing email from telnet
This is the body

Adding more lines to the body message.

When you have finished the email enter a dot:

.

This should give you the following response:

250 2.0.0 OK 1288307376 x23sm1104292weq.10

And now you need to end your session by typing the following and pressing enter:

QUIT

This should give you the following response:

221 2.0.0 closing connection x23sm1104292weq.10
Connection to host lost.

And your email should now be in the recipient’s mailbox!

Using a PHP variable in a text input value = statement

From the HTML point of view everything's been said, but to correct the PHP-side approach a little and taking thirtydot's and icktoofay's advice into account:

<?php echo '<input type="text" name="idtest" value="' . htmlspecialchars($idtest) . '">'; ?>

Pip error: Microsoft Visual C++ 14.0 is required

If you already have Visual Studio Build Tools installed but you're still getting that error, then you may need to "Modify" your installation to include the Visual C++ build tools.

To do that:

  1. Open up the Visual Studio Installer (you can search for it in the Start Menu if needed).

  2. Find Visual Studio Build Tools and click "Modify":

enter image description here

  1. Add a checkmark to Visual C++ build tools and then click "Modify" in the bottom right to install them:

enter image description here

After the C++ tools finish installing, run the pip command again and it should work.

Naming conventions for Java methods that return boolean

If you wish your class to be compatible with the Java Beans specification, so that tools utilizing reflection (e.g. JavaBuilders, JGoodies Binding) can recognize boolean getters, either use getXXXX() or isXXXX() as a method name. From the Java Beans spec:

8.3.2 Boolean properties

In addition, for boolean properties, we allow a getter method to match the pattern:

public boolean is<PropertyName>();

This “is<PropertyName>” method may be provided instead of a “get<PropertyName>” method, or it may be provided in addition to a “get<PropertyName>” method. In either case, if the “is<PropertyName>” method is present for a boolean property then we will use the “is<PropertyName>” method to read the property value. An example boolean property might be:

public boolean isMarsupial();
public void setMarsupial(boolean m);

In mocha testing while calling asynchronous function how to avoid the timeout Error: timeout of 2000ms exceeded

My issue was not sending the response back, so it was hanging. If you are using express make sure that res.send(data), res.json(data) or whatever the api method you wanna use is executed for the route you are testing.

JSON Post with Customized HTTPHeader Field

Just wanted to update this thread for future developers.

JQuery >1.12 Now supports being able to change every little piece of the request through JQuery.post ($.post({...}). see second function signature in https://api.jquery.com/jquery.post/

MVC4 StyleBundle not resolving images

After little investigation I concluded the followings: You have 2 options:

  1. go with transformations. Very usefull package for this: https://bundletransformer.codeplex.com/ you need following transformation for every problematic bundle:

    BundleResolver.Current = new CustomBundleResolver();
    var cssTransformer = new StyleTransformer();
    standardCssBundle.Transforms.Add(cssTransformer);
    bundles.Add(standardCssBundle);
    

Advantages: of this solution, you can name your bundle whatever you want => you can combine css files into one bundle from different directories. Disadvantages: You need to transform every problematic bundle

  1. Use the same relative root for the name of the bundle like where the css file is located. Advantages: there is no need for transformation. Disadvantages: You have limitation on combining css sheets from different directories into one bundle.

When using Trusted_Connection=true and SQL Server authentication, will this affect performance?

This will probably have some performance costs when creating the connection but as connections are pooled, they are created only once and then reused, so it won't make any difference to your application. But as always: measure it.


UPDATE:

There are two authentication modes:

  1. Windows Authentication mode (corresponding to a trusted connection). Clients need to be members of a domain.
  2. SQL Server Authentication mode. Clients are sending username/password at each connection

Automating running command on Linux from Windows using PuTTY

Code:

using System;
using System.Diagnostics;
namespace playSound
{
    class Program
    {
        public static void Main(string[] args)
        {
            Console.WriteLine(args[0]);

            Process amixerMediaProcess = new Process();
            amixerMediaProcess.StartInfo.CreateNoWindow = false;
            amixerMediaProcess.StartInfo.UseShellExecute = false;
            amixerMediaProcess.StartInfo.ErrorDialog = false;
            amixerMediaProcess.StartInfo.RedirectStandardOutput = false;
            amixerMediaProcess.StartInfo.RedirectStandardInput = false;
            amixerMediaProcess.StartInfo.RedirectStandardError = false;
            amixerMediaProcess.EnableRaisingEvents = true;

            amixerMediaProcess.StartInfo.Arguments = string.Format("{0}","-ssh username@"+args[0]+" -pw password -m commands.txt");
            amixerMediaProcess.StartInfo.FileName = "plink.exe";
            amixerMediaProcess.Start();


            Console.Write("Presskey to continue . . . ");
            Console.ReadKey(true);
    }
}

}

Sample commands.txt:

ps

Link: https://huseyincakir.wordpress.com/2015/08/27/send-commands-to-a-remote-device-over-puttyssh-putty-send-command-from-command-line/

'Best' practice for restful POST response

Returning the whole object on an update would not seem very relevant, but I can hardly see why returning the whole object when it is created would be a bad practice in a normal use case. This would be useful at least to get the ID easily and to get the timestamps when relevant. This is actually the default behavior got when scaffolding with Rails.

I really do not see any advantage to returning only the ID and doing a GET request after, to get the data you could have got with your initial POST.

Anyway as long as your API is consistent I think that you should choose the pattern that fits your needs the best. There is not any correct way of how to build a REST API, imo.

Why is the Java main method static?

The true entry point to any application is a static method. If the Java language supported an instance method as the "entry point", then the runtime would need implement it internally as a static method which constructed an instance of the object followed by calling the instance method.

With that out of the way, I'll examine the rationale for choosing a specific one of the following three options:

  1. A static void main() as we see it today.
  2. An instance method void main() called on a freshly constructed object.
  3. Using the constructor of a type as the entry point (e.g., if the entry class was called Program, then the execution would effectively consist of new Program()).

Breakdown:

static void main()

  1. Calls the static constructor of the enclosing class.
  2. Calls the static method main().

void main()

  1. Calls the static constructor of the enclosing class.
  2. Constructs an instance of the enclosing class by effectively calling new ClassName().
  3. Calls the instance method main().

new ClassName()

  1. Calls the static constructor of the enclosing class.
  2. Constructs an instance of the class (then does nothing with it and simply returns).

Rationale:

I'll go in reverse order for this one.

Keep in mind that one of the design goals of Java was to emphasize (require when possible) good object-oriented programming practices. In this context, the constructor of an object initializes the object, but should not be responsible for the object's behavior. Therefore, a specification that gave an entry point of new ClassName() would confuse the situation for new Java developers by forcing an exception to the design of an "ideal" constructor on every application.

By making main() an instance method, the above problem is certainly solved. However, it creates complexity by requiring the specification to list the signature of the entry class's constructor as well as the signature of the main() method.

In summary, specifying a static void main() creates a specification with the least complexity while adhering to the principle of placing behavior into methods. Considering how straightforward it is to implement a main() method which itself constructs an instance of a class and calls an instance method, there is no real advantage to specifying main() as an instance method.

R error "sum not meaningful for factors"

The error comes when you try to call sum(x) and x is a factor.

What that means is that one of your columns, though they look like numbers are actually factors (what you are seeing is the text representation)

simple fix, convert to numeric. However, it needs an intermeidate step of converting to character first. Use the following:

family[, 1] <- as.numeric(as.character( family[, 1] ))
family[, 3] <- as.numeric(as.character( family[, 3] ))

For a detailed explanation of why the intermediate as.character step is needed, take a look at this question: How to convert a factor to integer\numeric without loss of information?

what is right way to do API call in react js?

I would like you to have a look at redux http://redux.js.org/index.html

They have very well defined way of handling async calls ie API calls, and instead of using jQuery for API calls, I would like to recommend using fetch or request npm packages, fetch is currently supported by modern browsers, but a shim is also available for server side.

There is also this another amazing package superagent, which has alot many options when making an API request and its very easy to use.

How to set a ripple effect on textview or imageview on Android?

Ref : http://developer.android.com/training/material/animations.html,

http://wiki.workassis.com/category/android/android-xml/

<TextView
.
.
android:background="?attr/selectableItemBackgroundBorderless"
android:clickable="true"
/>

<ImageView
.
.
.
android:background="?attr/selectableItemBackgroundBorderless"
android:clickable="true"
/>

How to make picturebox transparent?

I've had a similar problem like this. You can not make Transparent picturebox easily such as picture that shown at top of this page, because .NET Framework and VS .NET objects are created by INHERITANCE! (Use Parent Property).

I solved this problem by RectangleShape and with the below code I removed background, if difference between PictureBox and RectangleShape is not important and doesn't matter, you can use RectangleShape easily.

private void CreateBox(int X, int Y, int ObjectType)
{
    ShapeContainer canvas = new ShapeContainer();
    RectangleShape box = new RectangleShape();
    box.Parent = canvas;
    box.Size = new System.Drawing.Size(100, 90);
    box.Location = new System.Drawing.Point(X, Y);
    box.Name = "Box" + ObjectType.ToString();
    box.BackColor = Color.Transparent;
    box.BorderColor = Color.Transparent;
    box.BackgroundImage = img.Images[ObjectType];// Load from imageBox Or any resource
    box.BackgroundImageLayout = ImageLayout.Stretch;
    box.BorderWidth = 0;
    canvas.Controls.Add(box);   // For feature use 
}

Get current date/time in seconds

Date.now()-Math.floor(Date.now()/1000/60/60/24)*24*60*60*1000

This should give you the milliseconds from the beginning of the day.

(Date.now()-Math.floor(Date.now()/1000/60/60/24)*24*60*60*1000)/1000

This should give you seconds.

(Date.now()-(Date.now()/1000/60/60/24|0)*24*60*60*1000)/1000

Same as previous except uses a bitwise operator to floor the amount of days.

java.sql.SQLException Parameter index out of range (1 > number of parameters, which is 0)

You will get this error when you call any of the setXxx() methods on PreparedStatement, while the SQL query string does not have any placeholders ? for this.

For example this is wrong:

String sql = "INSERT INTO tablename (col1, col2, col3) VALUES (val1, val2, val3)";
// ...

preparedStatement = connection.prepareStatement(sql);
preparedStatement.setString(1, val1); // Fail.
preparedStatement.setString(2, val2);
preparedStatement.setString(3, val3);

You need to fix the SQL query string accordingly to specify the placeholders.

String sql = "INSERT INTO tablename (col1, col2, col3) VALUES (?, ?, ?)";
// ...

preparedStatement = connection.prepareStatement(sql);
preparedStatement.setString(1, val1);
preparedStatement.setString(2, val2);
preparedStatement.setString(3, val3);

Note the parameter index starts with 1 and that you do not need to quote those placeholders like so:

String sql = "INSERT INTO tablename (col1, col2, col3) VALUES ('?', '?', '?')";

Otherwise you will still get the same exception, because the SQL parser will then interpret them as the actual string values and thus can't find the placeholders anymore.

See also:

MySQL: Fastest way to count number of rows

I handled tables for the German Government with sometimes 60 million records.

And we needed to know many times the total rows.

So we database programmers decided that in every table is record one always the record in which the total record numbers is stored. We updated this number, depending on INSERT or DELETE rows.

We tried all other ways. This is by far the fastest way.

How to select only date from a DATETIME field in MySQL?

SELECT DATE_FORMAT(NOW() - INTERVAL FLOOR(RAND() * 14) DAY,'%Y-%m-%d');

This one can be used to get date in 'yyyy-mm-dd' format.

NOW() function in PHP

Use strftime:

strftime("%F %T");
  • %F is the same as %Y-%m-%d.

  • %T is the same as %H:%M:%S.

Here's a demo on ideone.

What is the meaning of prepended double colon "::"?

:: is a operator of defining the namespace.

For example, if you want to use cout without mentioning using namespace std; in your code you write this:

std::cout << "test";

When no namespace is mentioned, that it is said that class belongs to global namespace.

Best way to get whole number part of a Decimal number

Depends on what you're doing.

For instance:

//bankers' rounding - midpoint goes to nearest even
GetIntPart(2.5) >> 2
GetIntPart(5.5) >> 6
GetIntPart(-6.5) >> -6

or

//arithmetic rounding - midpoint goes away from zero
GetIntPart(2.5) >> 3
GetIntPart(5.5) >> 6
GetIntPart(-6.5) >> -7

The default is always the former, which can be a surprise but makes very good sense.

Your explicit cast will do:

int intPart = (int)343564564.5
// intPart will be 343564564

int intPart = (int)343564565.5
// intPart will be 343564566

From the way you've worded the question it sounds like this isn't what you want - you want to floor it every time.

I would do:

Math.Floor(Math.Abs(number));

Also check the size of your decimal - they can be quite big, so you may need to use a long.

What does [object Object] mean?

Consider the following example:

const foo = {};
foo[Symbol.toStringTag] = "bar";
console.log("" + foo);

Which outputs

[object bar]

Basically, any object in javascript can define a property with the tag Symbol.toStringTag and override the output.

Behind the scenes construction of a new object in javascript prototypes from some object with a "toString" method. The default object provides this method as a property, and that method internally invokes the tag to determine how to coerce the object to a string. If the tag is present, then it's used, if missing you get "Object".

Should you set Symbol.toStringTag? Maybe. But relying on the string always being [object Object] for "true" objects is not the best idea.

How to take MySQL database backup using MySQL Workbench?

The Data Export function in MySQL Workbench allows 2 of the 3 ways. There's a checkbox Skip Table Data (no-data) on the export page which allows to either dump with or without data. Just dumping the data without meta data is not supported.

MVC 4 Edit modal form using Bootstrap

In $('.editor-container').click(function (){}), shouldn't var url = "/area/controller/MyEditAction"; be var url = "/area/controller/EditPartData";?

Cannot delete or update a parent row: a foreign key constraint fails

Basically, The reason behind these type of error is eventually you are trying to delete a tupple which has primary key (root table) & that primary key is used in child table as a foreign key. In this scenario in order to delete parent table data you have to remove child table data (in which foreign key is used). Thanks

notifyDataSetChanged not working on RecyclerView

In my case, force run #notifyDataSetChanged in main ui thread will fix

public void refresh() {
        clearSelection();
        // notifyDataSetChanged must run in main ui thread, if run in not ui thread, it will not update until manually scroll recyclerview
        ((Activity) ctx).runOnUiThread(new Runnable() {
            @Override
            public void run() {
                adapter.notifyDataSetChanged();
            }
        });
    }

Get names of all files from a folder with Ruby

If you want get an array of filenames including symlinks, use

Dir.new('/path/to/dir').entries.reject { |f| File.directory? f }

or even

Dir.new('/path/to/dir').reject { |f| File.directory? f }

and if you want to go without symlinks, use

Dir.new('/path/to/dir').select { |f| File.file? f }

As shown in other answers, use Dir.glob('/path/to/dir/**/*') instead of Dir.new('/path/to/dir') if you want to get all the files recursively.

C++ alignment when printing cout <<

At the time you emit the very first line,

Artist  Title   Price   Genre   Disc    Sale    Tax Cash

to achieve "alignment", you have to know "in advance" how wide each column will need to be (otherwise, alignment is impossible). Once you do know the needed width for each column (there are several possible ways to achieve that depending on where your data's coming from), then the setw function mentioned in the other answer will help, or (more brutally;-) you could emit carefully computed number of extra spaces (clunky, to be sure), etc. I don't recommend tabs anyway as you have no real control on how the final output device will render those, in general.

Back to the core issue, if you have each column's value in a vector<T> of some sort, for example, you can do a first formatting pass to determine the maximum width of the column, for example (be sure to take into account the width of the header for the column, too, of course).

If your rows are coming "one by one", and alignment is crucial, you'll have to cache or buffer the rows as they come in (in memory if they fit, otherwise on a disk file that you'll later "rewind" and re-read from the start), taking care to keep updated the vector of "maximum widths of each column" as the rows do come. You can't output anything (not even the headers!), if keeping alignment is crucial, until you've seen the very last row (unless you somehow magically have previous knowledge of the columns' widths, of course;-).

Trim last character from a string

An example Extension class to simplify this: -

internal static class String
{
    public static string TrimEndsCharacter(this string target, char character) => target?.TrimLeadingCharacter(character).TrimTrailingCharacter(character);
    public static string TrimLeadingCharacter(this string target, char character) => Match(target?.Substring(0, 1), character) ? target.Remove(0,1) : target;
    public static string TrimTrailingCharacter(this string target, char character) => Match(target?.Substring(target.Length - 1, 1), character) ? target.Substring(0, target.Length - 1) : target;

    private static bool Match(string value, char character) => !string.IsNullOrEmpty(value) && value[0] == character;
}

Usage

"!Something!".TrimLeadingCharacter('X'); // Result '!Something!' (No Change)
"!Something!".TrimTrailingCharacter('S'); // Result '!Something!' (No Change)
"!Something!".TrimEndsCharacter('g'); // Result '!Something!' (No Change)

"!Something!".TrimLeadingCharacter('!'); // Result 'Something!' (1st Character removed)
"!Something!".TrimTrailingCharacter('!'); // Result '!Something' (Last Character removed)
"!Something!".TrimEndsCharacter('!'); // Result 'Something'  (End Characters removed)

"!!Something!!".TrimLeadingCharacter('!'); // Result '!Something!!' (Only 1st instance removed)
"!!Something!!".TrimTrailingCharacter('!'); // Result '!!Something!' (Only Last instance removed)
"!!Something!!".TrimEndsCharacter('!'); // Result '!Something!'  (Only End instances removed)

How do I change button size in Python?

Configuring a button (or any widget) in Tkinter is done by calling a configure method "config"

To change the size of a button called button1 you simple call

button1.config( height = WHATEVER, width = WHATEVER2 )

If you know what size you want at initialization these options can be added to the constructor.

button1 = Button(self, text = "Send", command = self.response1, height = 100, width = 100) 

Cannot connect to MySQL 4.1+ using old authentication

On OSX, I used MacPorts to address the same problem when connecting to my siteground database. Siteground appears to be using 5.0.77mm0.1-log, but creating a new user account didn't fix the problem. This is what did

sudo port install php5-mysql -mysqlnd +mysql5

This downgrades the mysql driver that php will use.

right align an image using CSS HTML

To make the image move right:

float: right;

To make the text not wrapped:

clear: right;

For best practice, put the css code in your stylesheets file. Once you add more code, it will look messy and hard to edit.

How to manually set REFERER header in Javascript?

You can change the value of the referrer in the HTTP header using the Web Request API.

It requires a background js script for it's use. You can use the onBeforeSendHeaders as it modifies the header before the request is sent.

Your code will be something like this :

    chrome.webRequest.onBeforeSendHeaders.addEventListener(function(details){
    var newRef = "http://new-referer/path";
    var hasRef = false;
    for(var n in details.requestHeaders){
        hasRef = details.requestHeaders[n].name == "Referer";
        if(hasRef){
            details.requestHeaders[n].value = newRef;
         break;
        }
    }
    if(!hasRef){
        details.requestHeaders.push({name:"Referer",value:newRef});
    }
    return {requestHeaders:details.requestHeaders};
},
{
    urls:["http://target/*"]
},
[
    "requestHeaders",
    "blocking"
]);

urls : It acts as a request filter, and invokes the listener only for certain requests.

For more info: https://developer.chrome.com/extensions/webRequest

How can I get the timezone name in JavaScript?

You can simply write your own code by using the mapping table here: http://www.timeanddate.com/time/zones/

or, use moment-timezone library: http://momentjs.com/timezone/docs/

See zone.name; // America/Los_Angeles

or, this library: https://github.com/Canop/tzdetect.js

Index (zero based) must be greater than or equal to zero

Change this line:

Aboutme.Text = String.Format("{0}", reader.GetString(0));

How do you remove columns from a data.frame?

Can use setdiff function:

If there are more columns to keep than to delete: Suppose you want to delete 2 columns say col1, col2 from a data.frame DT; you can do the following:

DT<-DT[,setdiff(names(DT),c("col1","col2"))]

If there are more columns to delete than to keep: Suppose you want to keep only col1 and col2:

DT<-DT[,c("col1","col2")]

Node.js quick file server (static files over HTTP)

I haven't had much luck with any of the answers on this page, however, below seemed to do the trick.

Add a server.js file with the following content:

const express = require('express')
const path = require('path')
const port = process.env.PORT || 3000
const app = express()

// serve static assets normally
app.use(express.static(__dirname + '/dist'))

// handle every other route with index.html, which will contain
// a script tag to your application's JavaScript file(s).
app.get('*', function (request, response){
  response.sendFile(path.resolve(__dirname, 'dist', 'index.html'))
})

app.listen(port)
console.log("server started on port " + port)

Also make sure that you require express. Run yarn add express --save or npm install express --save depending on your setup (I can recommend yarn it's pretty fast).

You may change dist to whatever folder you are serving your content is. For my simple project, I wasn't serving from any folder, so I simply removed the dist filename.

Then you may run node server.js. As I had to upload my project to a Heroku server, I needed to add the following to my package.json file:

  "scripts": {
    "start": "node server.js"
  }

Sort a single String in Java

Question: sort a string in java

public class SortAStringInJava {
    public static void main(String[] args) {

        String str = "Protijayi";
// Method 1
        str = str.chars() // IntStream
                .sorted().collect(StringBuilder::new, StringBuilder::appendCodePoint, StringBuilder::append).toString();

        System.out.println(str);
        // Method 2
        str = Stream.of(str.split(" ")).sorted().collect(Collectors.joining());
        System.out.println(str);
    }
}

How to fix committing to the wrong Git branch?

If you already pushed your changes, you will need to force your next push after resetting the HEAD.

git reset --hard HEAD^
git merge COMMIT_SHA1
git push --force

Warning: a hard reset will undo any uncommitted modifications in your working copy, while a force push will completely overwrite the state of the remote branch with the current state of the local branch.

Just in case, on Windows (using the Windows command line, not Bash) it's actually four ^^^^ instead of one, so it's

git reset --hard HEAD^^^^

How to fix the Hibernate "object references an unsaved transient instance - save the transient instance before flushing" error

This occurred for me when persisting an entity in which the existing record in the database had a NULL value for the field annotated with @Version (for optimistic locking). Updating the NULL value to 0 in the database corrected this.

Check if int is between two numbers

Because the < operator (and most others) are binary operators (they take two arguments), and (true true) is not a valid boolean expression.

The Java language designers could have designed the language to allow syntax like the type you prefer, but (I'm guessing) they decided that it was not worth the more complex parsing rules.

How do I make an html link look like a button?

Use this class. It will make your link look the same as a button when applied using the button class on an a tag.

or

HERE IS ANOTHER DEMO JSFIDDLE

.button {
    display: inline-block;
    outline: none;
    cursor: pointer;
    border: solid 1px #da7c0c;
    background: #478dad;
    text-align: center;
    text-decoration: none;
    font: 14px/100% Arial, Helvetica, sans-serif;
    padding: .5em 2em .55em;
    text-shadow: 0 1px 1px rgba(0,0,0,.3);
    -webkit-border-radius: .5em; 
    -moz-border-radius: .5em;
    border-radius: .3em;
    -webkit-box-shadow: 0 1px 2px rgba(0,0,0,.2);
    -moz-box-shadow: 0 1px 2px rgba(0,0,0,.2);
    box-shadow: 0 1px 2px rgba(0,0,0,.2);
}
.button:hover {
    background: #f47c20;
    background: -webkit-gradient(linear, left top, left bottom, from(#f88e11), to(#f06015));
    background: -moz-linear-gradient(top,  #f88e11,  #f06015);
    filter:  progid:DXImageTransform.Microsoft.gradient(startColorstr='#f88e11', endColorstr='#f06015');
}
.button:active {
    position: relative;
    top: 1px;
}

how to remove css property using javascript?

This should do the trick - setting the inline style to normal for zoom:

$('div').attr("style", "zoom:normal;");

You are trying to add a non-nullable field 'new_field' to userprofile without a default

If you are early into the development cycle you can try this -

Remove/comment that model and all its usages. Apply migrations. That would delete that model and then add the model again, run migrations and you have a clean model with the new field added.

How do you clear the focus in javascript?

You can call window.focus();

but moving or losing the focus is bound to interfere with anyone using the tab key to get around the page.

you could listen for keycode 13, and forego the effect if the tab key is pressed.

Free tool to Create/Edit PNG Images?

ImageMagick and GD can handle PNGs too; heck, you could even do stuff with nothing but gdk-pixbuf. Are you looking for a graphical editor, or scriptable/embeddable libraries?

Implode an array with JavaScript?

array.join was not recognizing ";" how a separator, but replacing it with comma. Using jQuery, you can use $.each to implode an array (Note that output_saved_json is the array and tmp is the string that will store the imploded array):

var tmp = "";
$.each(output_saved_json, function(index,value) {
    tmp = tmp + output_saved_json[index] + ";";
});

output_saved_json = tmp.substring(0,tmp.length - 1); // remove last ";" added

I have used substring to remove last ";" added at the final without necessity. But if you prefer, you can use instead substring something like:

var tmp = "";
$.each(output_saved_json, function(index,value) {
    tmp = tmp + output_saved_json[index];

    if((index + 1) != output_saved_json.length) {
         tmp = tmp + ";";
    }
});

output_saved_json = tmp;

I think this last solution is more slower than the 1st one because it needs to check if index is different than the lenght of array every time while $.each do not end.

jQuery get the rendered height of an element?

With MooTools:

$('someDiv').getSize().y

How to validate a credit card number

You define the variable name re16digit but later refer to it as re10digit, which will throw an error. To simplify your code, you should use RegExp.prototype.test() rather than String.prototype.search():

function validate_creditcardnumber() {
    var re16digit = /^\d{16}$/;
    if (!re16digit.test(document.myform.CreditCardNumber.value)) {
        alert("Please enter your 16 digit credit card numbers");
        return false;
    }
}

Working demo: http://jsfiddle.net/Dxjkh/

As others have mentioned, you may be better off using a JavaScript implementation of the Luhn Algorithm. It's also worth mentioning that a check for 16 digits will fail for American Express (15 digits) and Diners (14 digits) cards.

How to insert selected columns from a CSV file to a MySQL database using LOAD DATA INFILE

Specify the name of columns in the CSV in the load data infile statement.

The code is like this:

LOAD DATA INFILE '/path/filename.csv'
INTO TABLE table_name
FIELDS TERMINATED BY ','
LINES TERMINATED BY '\r\n'
(column_name3, column_name5);

Here you go with adding data to only two columns(you can choose them with the name of the column) to the table.

The only thing you have to take care is that you have a CSV file(filename.csv) with two values per line(row). Otherwise please mention. I have a different solution.

Thank you.

Simplest PHP example for retrieving user_timeline with Twitter API version 1.1

$connection = new TwitterOAuth(CONSUMER_KEY, CONSUMER_SECRET, OAUTH_TOKEN, OAUTH_TOKEN_SECRET);

$timelines = $connection->get('statuses/user_timeline', array('screen_name' => 'NSE_NIFTY', 'count' => 100, 'include_rts' => 1));

SQL Server : converting varchar to INT

You could try updating the table to get rid of these characters:

UPDATE dbo.[audit]
  SET UserID = REPLACE(UserID, CHAR(0), '')
  WHERE CHARINDEX(CHAR(0), UserID) > 0;

But then you'll also need to fix whatever is putting this bad data into the table in the first place. In the meantime perhaps try:

SELECT CONVERT(INT, REPLACE(UserID, CHAR(0), ''))
  FROM dbo.[audit];

But that is not a long term solution. Fix the data (and the data type while you're at it). If you can't fix the data type immediately, then you can quickly find the culprit by adding a check constraint:

ALTER TABLE dbo.[audit]
  ADD CONSTRAINT do_not_allow_stupid_data
  CHECK (CHARINDEX(CHAR(0), UserID) = 0);

EDIT

Ok, so that is definitely a 4-digit integer followed by six instances of CHAR(0). And the workaround I posted definitely works for me:

DECLARE @foo TABLE(UserID VARCHAR(32));
INSERT @foo SELECT 0x31353831000000000000;

-- this succeeds:
SELECT CONVERT(INT, REPLACE(UserID, CHAR(0), '')) FROM @foo;

-- this fails:
SELECT CONVERT(INT, UserID) FROM @foo;

Please confirm that this code on its own (well, the first SELECT, anyway) works for you. If it does then the error you are getting is from a different non-numeric character in a different row (and if it doesn't then perhaps you have a build where a particular bug hasn't been fixed). To try and narrow it down you can take random values from the following query and then loop through the characters:

SELECT UserID, CONVERT(VARBINARY(32), UserID)
  FROM dbo.[audit]
  WHERE UserID LIKE '%[^0-9]%';

So take a random row, and then paste the output into a query like this:

DECLARE @x VARCHAR(32), @i INT;
SET @x = CONVERT(VARCHAR(32), 0x...); -- paste the value here
SET @i = 1;
WHILE @i <= LEN(@x)
BEGIN
  PRINT RTRIM(@i) + ' = ' + RTRIM(ASCII(SUBSTRING(@x, @i, 1)))
  SET @i = @i + 1;
END

This may take some trial and error before you encounter a row that fails for some other reason than CHAR(0) - since you can't really filter out the rows that contain CHAR(0) because they could contain CHAR(0) and CHAR(something else). For all we know you have values in the table like:

SELECT '15' + CHAR(9) + '23' + CHAR(0);

...which also can't be converted to an integer, whether you've replaced CHAR(0) or not.

I know you don't want to hear it, but I am really glad this is painful for people, because now they have more war stories to push back when people make very poor decisions about data types.

How to know which version of Symfony I have?

From inside your Symfony project, you can get the value in PHP this way:

$symfony_version = \Symfony\Component\HttpKernel\Kernel::VERSION;

Excel doesn't update value unless I hit Enter

I have the same problem with that guy here: mrexcel.com/forum/excel-questions/318115-enablecalculation.html Application.CalculateFull sold my problem. However I am afraid if this will happen again. I will try not to use EnableCalculation again.

RuntimeError on windows trying python multiprocessing

As @Ofer said, when you are using another libraries or modules, you should import all of them inside the if __name__ == '__main__':

So, in my case, ended like this:

if __name__ == '__main__':       
    import librosa
    import os
    import pandas as pd
    run_my_program()

Pandas How to filter a Series

In my case I had a panda Series where the values are tuples of characters:

Out[67]
0    (H, H, H, H)
1    (H, H, H, T)
2    (H, H, T, H)
3    (H, H, T, T)
4    (H, T, H, H)

Therefore I could use indexing to filter the series, but to create the index I needed apply. My condition is "find all tuples which have exactly one 'H'".

series_of_tuples[series_of_tuples.apply(lambda x: x.count('H')==1)]

I admit it is not "chainable", (i.e. notice I repeat series_of_tuples twice; you must store any temporary series into a variable so you can call apply(...) on it).

There may also be other methods (besides .apply(...)) which can operate elementwise to produce a Boolean index.

Many other answers (including accepted answer) using the chainable functions like:

  • .compress()
  • .where()
  • .loc[]
  • []

These accept callables (lambdas) which are applied to the Series, not to the individual values in those series!

Therefore my Series of tuples behaved strangely when I tried to use my above condition / callable / lambda, with any of the chainable functions, like .loc[]:

series_of_tuples.loc[lambda x: x.count('H')==1]

Produces the error:

KeyError: 'Level H must be same as name (None)'

I was very confused, but it seems to be using the Series.count series_of_tuples.count(...) function , which is not what I wanted.

I admit that an alternative data structure may be better:

  • A Category datatype?
  • A Dataframe (each element of the tuple becomes a column)
  • A Series of strings (just concatenate the tuples together):

This creates a series of strings (i.e. by concatenating the tuple; joining the characters in the tuple on a single string)

series_of_tuples.apply(''.join)

So I can then use the chainable Series.str.count

series_of_tuples.apply(''.join).str.count('H')==1

How can I move HEAD back to a previous location? (Detached head) & Undo commits

First reset locally:

git reset 23b6772

To see if you're on the right position, verify with:

git status

You will see something like:

On branch master Your branch is behind 'origin/master' by 17 commits, and can be fast-forwarded.

Then rewrite history on your remote tracking branch to reflect the change:

git push --force-with-lease // a useful command @oktober mentions in comments

Using --force-with-lease instead of --force will raise an error if others have meanwhile committed to the remote branch, in which case you should fetch first. More info in this article.

Get the current time in C

guys i got a new way get system time. though its lengthy and is full of silly works but in this way you can get system time in integer format.

#include <stdio.h>
#include <stdlib.h>

int main()
{
    FILE *fp;
    char hc1,hc2,mc1,mc2;
    int hi1,hi2,mi1,mi2,hour,minute;
    system("echo %time% >time.txt");
    fp=fopen("time.txt","r");
    if(fp==NULL)
       exit(1) ;
    hc1=fgetc(fp);
    hc2=fgetc(fp);
    fgetc(fp);
    mc1=fgetc(fp);
    mc2=fgetc(fp);
    fclose(fp);
    remove("time.txt");
    hi1=hc1;
    hi2=hc2;
    mi1=mc1;
    mi2=mc2;
    hi1-=48;
    hi2-=48;
    mi1-=48;
    mi2-=48;
    hour=hi1*10+hi2;
    minute=mi1*10+mi2;
    printf("Current time is %d:%d\n",hour,minute);
    return 0;
}

Javascript array value is undefined ... how do I test for that

try: typeof(predQuery[preId])=='undefined'
or more generally: typeof(yourArray[yourIndex])=='undefined'
You're comparing "undefined" to undefined, which returns false =)

How to open up a form from another form in VB.NET?

You may like to first create a dialogue by right clicking the project in solution explorer and in the code file type

dialogue1.show()

that's all !!!

Is JavaScript a pass-by-reference or pass-by-value language?

The MDN docs explain it clearly, without being too verbose:

The parameters of a function call are the function's arguments. Arguments are passed to functions by value. If the function changes the value of an argument, this change is not reflected globally or in the calling function. However, object references are values, too, and they are special: if the function changes the referred object's properties, that change is visible outside the function, (...)

Source: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions#Description

LINQ - Left Join, Group By, and Count

LATE ANSWER:

You shouldn't need the left join at all if all you're doing is Count(). Note that join...into is actually translated to GroupJoin which returns groupings like new{parent,IEnumerable<child>} so you just need to call Count() on the group:

from p in context.ParentTable
join c in context.ChildTable on p.ParentId equals c.ChildParentId into g
select new { ParentId = p.Id, Count = g.Count() }

In Extension Method syntax a join into is equivalent to GroupJoin (while a join without an into is Join):

context.ParentTable
    .GroupJoin(
                   inner: context.ChildTable
        outerKeySelector: parent => parent.ParentId,
        innerKeySelector: child => child.ParentId,
          resultSelector: (parent, children) => new { parent.Id, Count = children.Count() }
    );

How to install a python library manually

You need to install it in a directory in your home folder, and somehow manipulate the PYTHONPATH so that directory is included.

The best and easiest is to use virtualenv. But that requires installation, causing a catch 22. :) But check if virtualenv is installed. If it is installed you can do this:

$ cd /tmp
$ virtualenv foo
$ cd foo
$ ./bin/python

Then you can just run the installation as usual, with /tmp/foo/python setup.py install. (Obviously you need to make the virtual environment in your a folder in your home directory, not in /tmp/foo. ;) )

If there is no virtualenv, you can install your own local Python. But that may not be allowed either. Then you can install the package in a local directory for packages:

$ wget http://pypi.python.org/packages/source/s/six/six-1.0b1.tar.gz#md5=cbfcc64af1f27162a6a6b5510e262c9d
$ tar xvf six-1.0b1.tar.gz 
$ cd six-1.0b1/
$ pythonX.X setup.py   install --install-dir=/tmp/frotz

Now you need to add /tmp/frotz/pythonX.X/site-packages to your PYTHONPATH, and you should be up and running!

What's the HTML to have a horizontal space between two objects?

PHP does not do styling. You need to use html or css. Take a look at http://www.w3schools.com/tags/tag_hr.asp

In HTML 4.01, the


tag represents a horizontal rule.

In HTML 4.01, the <hr> tag represents a horizontal rule.

A tool to convert MATLAB code to Python

There are several tools for converting Matlab to Python code.

The only one that's seen recent activity (last commit from June 2018) is Small Matlab to Python compiler (also developed here: SMOP@chiselapp).

Other options include:

  • LiberMate: translate from Matlab to Python and SciPy (Requires Python 2, last update 4 years ago).
  • OMPC: Matlab to Python (a bit outdated).

Also, for those interested in an interface between the two languages and not conversion:

  • pymatlab: communicate from Python by sending data to the MATLAB workspace, operating on them with scripts and pulling back the resulting data.
  • Python-Matlab wormholes: both directions of interaction supported.
  • Python-Matlab bridge: use Matlab from within Python, offers matlab_magic for iPython, to execute normal matlab code from within ipython.
  • PyMat: Control Matlab session from Python.
  • pymat2: continuation of the seemingly abandoned PyMat.
  • mlabwrap, mlabwrap-purepy: make Matlab look like Python library (based on PyMat).
  • oct2py: run GNU Octave commands from within Python.
  • pymex: Embeds the Python Interpreter in Matlab, also on File Exchange.
  • matpy: Access MATLAB in various ways: create variables, access .mat files, direct interface to MATLAB engine (requires MATLAB be installed).
  • MatPy: Python package for numerical linear algebra and plotting with a MatLab-like interface.

Btw might be helpful to look here for other migration tips:

On a different note, though I'm not a fortran fan at all, for people who might find it useful there is:

How to Set the Background Color of a JButton on the Mac OS

I own a mac too! here is the code that will work:

myButton.setBackground(Color.RED);
myButton.setOpaque(true); //Sets Button Opaque so it works

before doing anything or adding any components set the look and feel so it looks better:

try{
   UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());
 }catch(Exception e){
  e.printStackTrace(); 
 }

That is Supposed to change the look and feel to the cross platform look and feel, hope i helped! :)

How to detect if URL has changed after hash in JavaScript

In modern browsers (IE8+, FF3.6+, Chrome), you can just listen to the hashchange event on window.

In some old browsers, you need a timer that continually checks location.hash. If you're using jQuery, there is a plugin that does exactly that.

Python threading. How do I lock a thread?

You can see that your locks are pretty much working as you are using them, if you slow down the process and make them block a bit more. You had the right idea, where you surround critical pieces of code with the lock. Here is a small adjustment to your example to show you how each waits on the other to release the lock.

import threading
import time
import inspect

class Thread(threading.Thread):
    def __init__(self, t, *args):
        threading.Thread.__init__(self, target=t, args=args)
        self.start()

count = 0
lock = threading.Lock()

def incre():
    global count
    caller = inspect.getouterframes(inspect.currentframe())[1][3]
    print "Inside %s()" % caller
    print "Acquiring lock"
    with lock:
        print "Lock Acquired"
        count += 1  
        time.sleep(2)  

def bye():
    while count < 5:
        incre()

def hello_there():
    while count < 5:
        incre()

def main():    
    hello = Thread(hello_there)
    goodbye = Thread(bye)


if __name__ == '__main__':
    main()

Sample output:

...
Inside hello_there()
Acquiring lock
Lock Acquired
Inside bye()
Acquiring lock
Lock Acquired
...

Intersection and union of ArrayLists in Java

Here's a plain implementation without using any third-party library. Main advantage over retainAll, removeAll and addAll is that these methods don't modify the original lists input to the methods.

public class Test {

    public static void main(String... args) throws Exception {

        List<String> list1 = new ArrayList<String>(Arrays.asList("A", "B", "C"));
        List<String> list2 = new ArrayList<String>(Arrays.asList("B", "C", "D", "E", "F"));

        System.out.println(new Test().intersection(list1, list2));
        System.out.println(new Test().union(list1, list2));
    }

    public <T> List<T> union(List<T> list1, List<T> list2) {
        Set<T> set = new HashSet<T>();

        set.addAll(list1);
        set.addAll(list2);

        return new ArrayList<T>(set);
    }

    public <T> List<T> intersection(List<T> list1, List<T> list2) {
        List<T> list = new ArrayList<T>();

        for (T t : list1) {
            if(list2.contains(t)) {
                list.add(t);
            }
        }

        return list;
    }
}

Groovy - How to compare the string?

use def variable, when you want to compare any String. Use below code for that type of comparison.

def variable name = null

SQL query give you some return. Use function with return type def.

def functionname(def variablename){

return variable name

}

if ("$variable name" == "true"){

}

when do you need .ascx files and how would you use them?

If you have a block of code+html that appears on several pages and is sort of independent of that page (say a block of latest news items), you could copy/paste the code to every page.

It is however better to put that code in its own block and just include that block on every page that needs it. That "block" is an ascx file.

Show MySQL host via SQL Command

I think you try to get the remote host of the conneting user...

You can get a String like 'myuser@localhost' from the command:

SELECT USER()

You can split this result on the '@' sign, to get the parts:

-- delivers the "remote_host" e.g. "localhost" 
SELECT SUBSTRING_INDEX(USER(), '@', -1) 

-- delivers the user-name e.g. "myuser"
SELECT SUBSTRING_INDEX(USER(), '@', 1)

if you are conneting via ip address you will get the ipadress instead of the hostname.

ERROR: SQLSTATE[HY000] [2002] No connection could be made because the target machine actively refused it

You should restart your Xampp or whatever server you're runnung, make sure sq

How do I select the parent form based on which submit button is clicked?

To get the form that the submit is inside why not just

this.form

Easiest & quickest path to the result.

Selecting the last value of a column

Is it acceptable to answer the original question with a strictly off topic answer:) You can write a formula in the spreadsheet to do this. Ugly perhaps? but effective in the normal operating of a spreadsheet.

=indirect("R"&ArrayFormula(max((G:G<>"")*row(G:G)))&"C"&7)


(G:G<>"") gives an array of true false values representing non-empty/empty cells
(G:G<>"")*row(G:G) gives an array of row numbers with zeros where cell is empty
max((G:G<>"")*row(G:G)) is the last non-empty cell in G

This is offered as a thought for a range of questions in the script area that could be delivered reliably with array formulas which have the advantage of often working in similar fashion in excel and openoffice.

Using a .php file to generate a MySQL dump

Please reffer to the following link which contains a scriptlet that will help you: http://davidwalsh.name/backup-mysql-database-php

Note: This script may contain bugs with NULL data types

Array of structs example

You've started right - now you just need to fill the each student structure in the array:

struct student
{
    public int s_id;
    public String s_name, c_name, dob;
}
class Program
{
    static void Main(string[] args)
    {
        student[] arr = new student[4];

        for(int i = 0; i < 4; i++)
        {
            Console.WriteLine("Please enter StudentId, StudentName, CourseName, Date-Of-Birth");


            arr[i].s_id = Int32.Parse(Console.ReadLine());
            arr[i].s_name = Console.ReadLine();
            arr[i].c_name = Console.ReadLine();
            arr[i].s_dob = Console.ReadLine();
       }
    }
}

Now, just iterate once again and write these information to the console. I will let you do that, and I will let you try to make program to take any number of students, and not just 4.