Programs & Examples On #Struts

The Apache Struts web framework is a free open-source solution for creating Java web applications.

Difference between Spring MVC and Struts MVC

Spring MVC is deeply integreated in Spring, Struts MVC is not.

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" />

Address already in use: JVM_Bind java

I was having this problem too. For me, I couldn't start/stop openfire (it said it was stopped, but everything was still running)

sudo /etc/init.d/openfire stop
sudo /etc/init.d/openfire start

Also, restarting apache did not help either

sudo /etc/init.d/apache2 restart

The errors were inside:

/opt/openfire/logs/stderror.log
Error creating server listener on port 5269: Address already in use
Error creating server listener on port 5222: Address already in use

The way I fixed this, I had to actually turn off the server inside the admin area for my host.

Invoke or BeginInvoke cannot be called on a control until the window handle has been created

var that = this; // this is a form
(new Thread(()=> {

    var action= new Action(() => {
       something
    }));

    if(!that.IsDisposed)
    {
        if(that.IsHandleCreated)
        {
            //if (that.InvokeRequired)
                that.BeginInvoke(action);
            //else
            // action.Invoke();
        }
        else
            that.HandleCreated+=(sender,event) => {
                action.Invoke();
            };
    }


})).Start();

Conditionally hide CommandField or ButtonField in Gridview

You can hide a CommandField or ButtonField based on the position (index) in the GridView.

For example, if your CommandField is in the first position (index = 0), you can hide it adding the following code in the event RowDataBound of the GridView:

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        ((System.Web.UI.Control)e.Row.Cells[0].Controls[0]).Visible = false;
    }
}

http://localhost/ not working on Windows 7. What's the problem?

Try adding the following tags in the wwwroot folder web.config file. These tags should be added as a child of the configuration tags as below.

-configuration-
--system.webServer--
---validation validateIntegratedModeConfiguration="false" ---
--/system.webServer--
-/configuration-

Angularjs error Unknown provider

Make sure you are loading those modules (myApp.services and myApp.directives) as dependencies of your main app module, like this:

angular.module('myApp', ['myApp.directives', 'myApp.services']);

plunker: http://plnkr.co/edit/wxuFx6qOMfbuwPq1HqeM?p=preview

How to change scroll bar position with CSS?

Try this out. Hope this helps

<div id="single" dir="rtl">
    <div class="common">Single</div>
</div>

<div id="both" dir="ltr">
    <div class="common">Both</div>
</div>



#single, #both{
    width: 100px;
    height: 100px;
    overflow: auto;
    margin: 0 auto;
    border: 1px solid gray;
}


.common{
    height: 150px;
    width: 150px;
}

Unable to run 'adb root' on a rooted Android phone

I finally found out how to do this! Basically you need to run adb shell first and then while you're in the shell run su, which will switch the shell to run as root!

$: adb shell
$: su

The one problem I still have is that sqlite3 is not installed so the command is not recognized.

Compare two dates in Java

Here's what you can do for say yyyy-mm-dd comparison:

GregorianCalendar gc= new GregorianCalendar();
gc.setTimeInMillis(System.currentTimeMillis());
gc.roll(GregorianCalendar.DAY_OF_MONTH, true);

Date d1 = new Date();
Date d2 = gc.getTime();

SimpleDateFormat sf= new SimpleDateFormat("yyyy-MM-dd");

if(sf.format(d2).hashCode() < sf.format(d1).hashCode())
{
    System.out.println("date 2 is less than date 1");
}
else
{
    System.out.println("date 2 is equal or greater than date 1");
}

How to position three divs in html horizontally?

Most easiest way
I can see the question is answered , I'm giving this answer for the ones who is having this question in future


Its not good practise to code inline css , and also ID for all inner div's , always try to use class for styling .Using inline css is a very bad practise if you are trying to be a professional web designer.

here in your question I have given a wrapper class for the parent div and all the inside div's are child div's in css you can call inner div's using nth-child selector.

I want to point few things here

1 - Do not use inline css ( it is very bad practise )

2 - Try to use classes instead of id's because if you give an id you can use it only once, but if you use a class you can use it many times and also you can style of them using that class so you write less code.


codepen link for my answer

https://codepen.io/feizel/pen/JELGyB


_x000D_
_x000D_
            .wrapper{width:100%;}_x000D_
            .box{float:left; height:100px;}_x000D_
            .box:nth-child(1){_x000D_
               width:25%;_x000D_
               background-color:red; _x000D_
        _x000D_
            }_x000D_
            .box:nth-child(2){_x000D_
               width:50%;_x000D_
              background-color:green; _x000D_
            }_x000D_
            .box:nth-child(3){_x000D_
               width:25%;_x000D_
              background-color:yellow; _x000D_
            }
_x000D_
 _x000D_
    <div class="wrapper">_x000D_
        <div class="box">_x000D_
        Left Side Menu_x000D_
        </div>_x000D_
        <div class="box">_x000D_
        Random Content_x000D_
        </div>_x000D_
        <div class="box">_x000D_
        Right Side Menu_x000D_
        </div>_x000D_
    </div>
_x000D_
_x000D_
_x000D_

How to a convert a date to a number and back again in MATLAB

Use DATESTR

>> datestr(40189)
ans =
12-Jan-0110

Unfortunately, Excel starts counting at 1-Jan-1900. Find out how to convert serial dates from Matlab to Excel by using DATENUM

>> datenum(2010,1,11)
ans =
      734149
>> datenum(2010,1,11)-40189
ans =
      693960
>> datestr(40189+693960)
ans =
11-Jan-2010

In other words, to convert any serial Excel date, call

datestr(excelSerialDate + 693960)

EDIT

To get the date in mm/dd/yyyy format, call datestr with the specified format

excelSerialDate = 40189;
datestr(excelSerialDate + 693960,'mm/dd/yyyy')
ans =
01/11/2010

Also, if you want to get rid of the leading zero for the month, you can use REGEXPREP to fix things

excelSerialDate = 40189;
regexprep(datestr(excelSerialDate + 693960,'mm/dd/yyyy'),'^0','')
ans =
1/11/2010

Django ManyToMany filter()

Just restating what Tomasz said.

There are many examples of FOO__in=... style filters in the many-to-many and many-to-one tests. Here is syntax for your specific problem:

users_in_1zone = User.objects.filter(zones__id=<id1>)
# same thing but using in
users_in_1zone = User.objects.filter(zones__in=[<id1>])

# filtering on a few zones, by id
users_in_zones = User.objects.filter(zones__in=[<id1>, <id2>, <id3>])
# and by zone object (object gets converted to pk under the covers)
users_in_zones = User.objects.filter(zones__in=[zone1, zone2, zone3])

The double underscore (__) syntax is used all over the place when working with querysets.

How to simplify a null-safe compareTo() implementation?

Using Java 8:

private static Comparator<String> nullSafeStringComparator = Comparator
        .nullsFirst(String::compareToIgnoreCase); 

private static Comparator<Metadata> metadataComparator = Comparator
        .comparing(Metadata::getName, nullSafeStringComparator)
        .thenComparing(Metadata::getValue, nullSafeStringComparator);

public int compareTo(Metadata that) {
    return metadataComparator.compare(this, that);
}

Getting "error": "unsupported_grant_type" when trying to get a JWT by calling an OWIN OAuth secured Web Api via Postman

  1. Note the URL: localhost:55828/token (not localhost:55828/API/token)
  2. Note the request data. Its not in json format, its just plain data without double quotes. [email protected]&password=Test123$&grant_type=password
  3. Note the content type. Content-Type: 'application/x-www-form-urlencoded' (not Content-Type: 'application/json')
  4. When you use JavaScript to make post request, you may use following:

    $http.post("localhost:55828/token", 
      "userName=" + encodeURIComponent(email) +
        "&password=" + encodeURIComponent(password) +
        "&grant_type=password",
      {headers: { 'Content-Type': 'application/x-www-form-urlencoded' }}
    ).success(function (data) {//...
    

See screenshots below from Postman:

Postman Request

Postman Request Header

Swift 2: Call can throw, but it is not marked with 'try' and the error is not handled

When calling a function that is declared with throws in Swift, you must annotate the function call site with try or try!. For example, given a throwing function:

func willOnlyThrowIfTrue(value: Bool) throws {
  if value { throw someError }
}

this function can be called like:

func foo(value: Bool) throws {
  try willOnlyThrowIfTrue(value)
}

Here we annotate the call with try, which calls out to the reader that this function may throw an exception, and any following lines of code might not be executed. We also have to annotate this function with throws, because this function could throw an exception (i.e., when willOnlyThrowIfTrue() throws, then foo will automatically rethrow the exception upwards.

If you want to call a function that is declared as possibly throwing, but which you know will not throw in your case because you're giving it correct input, you can use try!.

func bar() {
  try! willOnlyThrowIfTrue(false)
}

This way, when you guarantee that code won't throw, you don't have to put in extra boilerplate code to disable exception propagation.

try! is enforced at runtime: if you use try! and the function does end up throwing, then your program's execution will be terminated with a runtime error.

Most exception handling code should look like the above: either you simply propagate exceptions upward when they occur, or you set up conditions such that otherwise possible exceptions are ruled out. Any clean up of other resources in your code should occur via object destruction (i.e. deinit()), or sometimes via defered code.

func baz(value: Bool) throws {

  var filePath = NSBundle.mainBundle().pathForResource("theFile", ofType:"txt")
  var data = NSData(contentsOfFile:filePath)

  try willOnlyThrowIfTrue(value)

  // data and filePath automatically cleaned up, even when an exception occurs.
}

If for whatever reason you have clean up code that needs to run but isn't in a deinit() function, you can use defer.

func qux(value: Bool) throws {
  defer {
    print("this code runs when the function exits, even when it exits by an exception")
  }

  try willOnlyThrowIfTrue(value)
}

Most code that deals with exceptions simply has them propagate upward to callers, doing cleanup on the way via deinit() or defer. This is because most code doesn't know what to do with errors; it knows what went wrong, but it doesn't have enough information about what some higher level code is trying to do in order to know what to do about the error. It doesn't know if presenting a dialog to the user is appropriate, or if it should retry, or if something else is appropriate.

Higher level code, however, should know exactly what to do in the event of any error. So exceptions allow specific errors to bubble up from where they initially occur to the where they can be handled.

Handling exceptions is done via catch statements.

func quux(value: Bool) {
  do {
    try willOnlyThrowIfTrue(value)
  } catch {
    // handle error
  }
}

You can have multiple catch statements, each catching a different kind of exception.

  do {
    try someFunctionThatThowsDifferentExceptions()
  } catch MyErrorType.errorA {
    // handle errorA
  } catch MyErrorType.errorB {
    // handle errorB
  } catch {
    // handle other errors
  }

For more details on best practices with exceptions, see http://exceptionsafecode.com/. It's specifically aimed at C++, but after examining the Swift exception model, I believe the basics apply to Swift as well.

For details on the Swift syntax and error handling model, see the book The Swift Programming Language (Swift 2 Prerelease).

Why do I need an IoC container as opposed to straightforward DI code?

The biggest benefit of using IoC containers for me (personally, I use Ninject) has been to eliminate the passing around of settings and other sorts of global state objects.

I don't program for the web, mine is a console application and in many places deep in the object tree I need to have access to the settings or metadata specified by the user that are created on a completely separate branch of the object tree. With IoC I simply tell Ninject to treat the Settings as a singleton (because there is always only one instance of them), request the Settings or Dictionary in the constructor and presto ... they magically appear when I need them!

Without using an IoC container I would have to pass the settings and/or metadata down through 2, 3, ..., n objects before it was actually used by the object that needed it.

There are many other benefits to DI/IoC containers as other people have detailed here and moving from the idea of creating objects to requesting objects can be mind-bending, but using DI was very helpful for me and my team so maybe you can add it to your arsenal!

Convert to date format dd/mm/yyyy

Try this:

$old_date = Date_create("2010-04-19 18:31:27");
$new_date = Date_format($old_date, "d/m/Y");

Have nginx access_log and error_log log to STDOUT and STDERR of master process

In docker image of PHP-FPM, i've see such approach:

# cat /usr/local/etc/php-fpm.d/docker.conf
[global]
error_log = /proc/self/fd/2

[www]
; if we send this to /proc/self/fd/1, it never appears
access.log = /proc/self/fd/2

Android findViewById() in Custom View

You can try something like this:

Inside customview constructor:

mContext = context;

Next inside customview you can call:

((MainActivity) mContext).updateText( text );

Inside MainAcivity define:

public void updateText(final String text) {

     TextView txtView = (TextView) findViewById(R.id.text);
     txtView.setText(text);
}

It works for me.

pandas get column average/mean

If you only want the mean of the weight column, select the column (which is a Series) and call .mean():

In [479]: df
Out[479]: 
         ID  birthyear    weight
0    619040       1962  0.123123
1    600161       1963  0.981742
2  25602033       1963  1.312312
3    624870       1987  0.942120

In [480]: df["weight"].mean()
Out[480]: 0.83982437500000007

System.Net.WebException HTTP status code

this works only if WebResponse is a HttpWebResponse.

try
{
    ...
}
catch (System.Net.WebException exc)
{
    var webResponse = exc.Response as System.Net.HttpWebResponse;
    if (webResponse != null && 
        webResponse.StatusCode == System.Net.HttpStatusCode.Unauthorized)
    {
        MessageBox.Show("401");
    }
    else
        throw;
}

Putting text in top left corner of matplotlib plot

One solution would be to use the plt.legend function, even if you don't want an actual legend. You can specify the placement of the legend box by using the loc keyterm. More information can be found at this website but I've also included an example showing how to place a legend:

ax.scatter(xa,ya, marker='o', s=20, c="lightgreen", alpha=0.9)
ax.scatter(xb,yb, marker='o', s=20, c="dodgerblue", alpha=0.9)
ax.scatter(xc,yc marker='o', s=20, c="firebrick", alpha=1.0)
ax.scatter(xd,xd,xd, marker='o', s=20, c="goldenrod", alpha=0.9)
line1 = Line2D(range(10), range(10), marker='o', color="goldenrod")
line2 = Line2D(range(10), range(10), marker='o',color="firebrick")
line3 = Line2D(range(10), range(10), marker='o',color="lightgreen")
line4 = Line2D(range(10), range(10), marker='o',color="dodgerblue")
plt.legend((line1,line2,line3, line4),('line1','line2', 'line3', 'line4'),numpoints=1, loc=2) 

Note that because loc=2, the legend is in the upper-left corner of the plot. And if the text overlaps with the plot, you can make it smaller by using legend.fontsize, which will then make the legend smaller.

How do I use a pipe to redirect the output of one command to the input of another?

Try this. Copy this into a batch file - such as send.bat - and then simply run send.bat to send the message from the temperature program to the prismcom program.

temperature.exe > msg.txt
set /p msg= < msg.txt
prismcom.exe usb "%msg%"

Set Radiobuttonlist Selected from Codebehind

The best option, in my opinion, is to use the Value property for the ListItem, which is available in the RadioButtonList.

I must remark that ListItem does NOT have an ID property.

So, in your case, to select the second element (option2) that would be:

// SelectedValue expects a string
radio1.SelectedValue = "1"; 

Alternatively, yet in very much the same vein you may supply an int to SelectedIndex.

// SelectedIndex expects an int, and are identified in the same order as they are added to the List starting with 0.
radio1.SelectedIndex = 1; 

How to use index in select statement?

The optimiser will judge if the use of your index will make your query run faster, and if it is, it will use the index.

Depending on your RDBMS you can force the use of an index, although it is not recommended unless you know what you are doing.

In general you should index columns that you use in table join's and where statements

XmlWriter to Write to a String Instead of to a File

I know this is old and answered, but here is another way to do it. Particularly if you don't want the UTF8 BOM at the start of your string and you want the text indented:

using (var ms = new MemoryStream())
using (var x = new XmlTextWriter(ms, new UTF8Encoding(false)) 
                   { Formatting = Formatting.Indented })
{
     // ...
     return Encoding.UTF8.GetString(ms.ToArray());
}

laravel the requested url was not found on this server

I have faced the same problem in cPanel and I fixed my problem to add in .htaccess file below these line

# Handle Front Controller...
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^ index.php [L]

400 BAD request HTTP error code meaning?

Using 400 status codes for any other purpose than indicating that the request is malformed is just plain wrong.

If the request payload contains a byte-sequence that could not be parsed as application/json (if the server expects that dataformat), the appropriate status code is 415:

The server is refusing to service the request because the entity of the request is in a format not supported by the requested resource for the requested method.

If the request payload is syntactically correct but semantically incorrect, the non-standard 422 response code may be used, or the standard 403 status code:

The server understood the request, but is refusing to fulfill it. Authorization will not help and the request SHOULD NOT be repeated.

How to run .NET Core console app from the command line

You can also run your app like any other console applications but only after the publish.

Let's suppose you have the simple console app named MyTestConsoleApp. Open the package manager console and run the following command:

dotnet publish -c Debug -r win10-x64 

-c flag mean that you want to use the debug configuration (in other case you should use Release value) - r flag mean that your application will be runned on Windows platform with x64 architecture.

When the publish procedure will be finished your will see the *.exe file located in your bin/Debug/publish directory.

Now you can call it via command line tools. So open the CMD window (or terminal) move to the directory where your *.exe file is located and write the next command:

>> MyTestConsoleApp.exe argument-list

For example:

>> MyTestConsoleApp.exe --input some_text -r true

Help needed with Median If in Excel

Expanding on Brian Camire's Answer:

Using =MEDIAN(IF($A$1:$A$6="Airline",$B$1:$B$6,"")) with CTRL+SHIFT+ENTER will include blank cells in the calculation. Blank cells will be evaluated as 0 which results in a lower median value. The same is true if using the average funtion. If you don't want to include blank cells in the calculation, use a nested if statement like so:

=MEDIAN(IF($A$1:$A$6="Airline",IF($B$1:$B$6<>"",$B$1:$B$6)))

Don't forget to press CTRL+SHIFT+ENTER to treat the formula as an "array formula".

ggplot combining two plots from different data.frames

As Baptiste said, you need to specify the data argument at the geom level. Either

#df1 is the default dataset for all geoms
(plot1 <- ggplot(df1, aes(v, p)) + 
    geom_point() +
    geom_step(data = df2)
)

or

#No default; data explicitly specified for each geom
(plot2 <- ggplot(NULL, aes(v, p)) + 
      geom_point(data = df1) +
      geom_step(data = df2)
)

How to press/click the button using Selenium if the button does not have the Id?

You don't need to use only identifier as elements locators. You can use a few ways to find an element. Read this article and choose the best for you.

Collision Detection between two images in Java

You don't want to have the collision check code inside the painting code. The painting needs to be fast. Collision can go in the game loop. Therefore you need an internal representation of the objects independent of their sprites.

How to sum all the values in a dictionary?

d = {'key1': 1,'key2': 14,'key3': 47}
sum1 = sum(d[item] for item in d)
print(sum1)

you can do it using the for loop

Multiline text in JLabel

String labelText ="<html>Name :"+name+"<br>Surname :"+surname+"<br>Gender :"+gender+"</html>";
JLabel label=new JLabel(labelText);
label.setVisible(true);
label.setBounds(10, 10,300, 100);
dialog.add(label);

ERROR 2006 (HY000): MySQL server has gone away

I solved the error ERROR 2006 (HY000) at line 97: MySQL server has gone away and successfully migrated a >5GB sql file by performing these two steps in order:

  1. Created /etc/my.cnf as others have recommended, with the following contents:

    [mysql]
    connect_timeout = 43200
    max_allowed_packet = 2048M
    net_buffer_length = 512M
    debug-info = TRUE
    
  2. Appending the flags --force --wait --reconnect to the command (i.e. mysql -u root -p -h localhost my_db < file.sql --verbose --force --wait --reconnect).

Important Note: It was necessary to perform both steps, because if I didn't bother making the changes to /etc/my.cnf file as well as appending those flags, some of the tables were missing after the import.

System used: OSX El Capitan 10.11.5; mysql Ver 14.14 Distrib 5.5.51 for osx10.8 (i386)

How can I reload .emacs after changing it?

Very strange that the very convenient

M-x eval-buffer

is not mentioned here.

It immediately evaluates all code in the buffer, its the quickest method, if your .emacs is idempotent.

How do I space out the child elements of a StackPanel?

sometimes you need to set Padding, not Margin to make space between items smaller than default

Proper MIME media type for PDF files

The standard MIME type is application/pdf. The assignment is defined in RFC 3778, The application/pdf Media Type, referenced from the MIME Media Types registry.

MIME types are controlled by a standards body, The Internet Assigned Numbers Authority (IANA). This is the same organization that manages the root name servers and the IP address space.

The use of x-pdf predates the standardization of the MIME type for PDF. MIME types in the x- namespace are considered experimental, just as those in the vnd. namespace are considered vendor-specific. x-pdf might be used for compatibility with old software.

Backup/Restore a dockerized PostgreSQL database

I had this issue while trying to use a db_dump to restore a db. I normally use dbeaver to restore- however received a psql dump, so had to figure out a method to restore using the docker container.

The methodology recommended by Forth and edited by Soviut worked for me:

cat your_dump.sql | docker exec -i your-db-container psql -U postgres -d dbname

(since this was a single db dump and not multiple db's i included the name)

However, in order to get this to work, I had to also go into the virtualenv that the docker container and project were in. This eluded me for a bit before figuring it out- as I was receiving the following docker error.

read unix @->/var/run/docker.sock: read: connection reset by peer

This can be caused by the file /var/lib/docker/network/files/local-kv.db .I don't know the accuracy of this statement: but I believe I was seeing this as I do not user docker locally, so therefore did not have this file, which it was looking for, using Forth's answer.

I then navigated to correct directory (with the project) activated the virtualenv and then ran the accepted answer. Boom, worked like a top. Hope this helps someone else out there!

Entity Framework .Remove() vs. .DeleteObject()

If you really want to use Deleted, you'd have to make your foreign keys nullable, but then you'd end up with orphaned records (which is one of the main reasons you shouldn't be doing that in the first place). So just use Remove()

ObjectContext.DeleteObject(entity) marks the entity as Deleted in the context. (It's EntityState is Deleted after that.) If you call SaveChanges afterwards EF sends a SQL DELETE statement to the database. If no referential constraints in the database are violated the entity will be deleted, otherwise an exception is thrown.

EntityCollection.Remove(childEntity) marks the relationship between parent and childEntity as Deleted. If the childEntity itself is deleted from the database and what exactly happens when you call SaveChanges depends on the kind of relationship between the two:

A thing worth noting is that setting .State = EntityState.Deleted does not trigger automatically detected change. (archive)

Dynamically add child components in React

Firstly a warning: you should never tinker with DOM that is managed by React, which you are doing by calling ReactDOM.render(<SampleComponent ... />);

With React, you should use SampleComponent directly in the main App.

var App = require('./App.js');
var SampleComponent = require('./SampleComponent.js');
ReactDOM.render(<App/>, document.body);

The content of your Component is irrelevant, but it should be used like this:

var App = React.createClass({
    render: function() {
        return (
            <div>
                <h1>App main component! </h1>
                <SampleComponent name="SomeName"/>
            </div>
        );
    }
});

You can then extend your app component to use a list.

var App = React.createClass({
    render: function() {
        var componentList = [
            <SampleComponent name="SomeName1"/>,
            <SampleComponent name="SomeName2"/>
        ]; // Change this to get the list from props or state
        return (
            <div>
                <h1>App main component! </h1>
                {componentList}
            </div>
        );
    }
});

I would really recommend that you look at the React documentation then follow the "Get Started" instructions. The time you spend on that will pay off later.

https://facebook.github.io/react/index.html

Python; urllib error: AttributeError: 'bytes' object has no attribute 'read'

Use json.loads not json.load.

(load loads from a file-like object, loads from a string. So you could just as well omit the .read() call instead.)

How to fix syntax error, unexpected T_IF error in php?

Here is the issue

  $total_result = $result->num_rows;

try this

<?php
if ($result = $mysqli->query("SELECT * FROM players ORDER BY id"))
{
    if ($result->num_rows > 0)
    {
        $total_result = $result->num_rows;
        $total_pages = ceil($total_result / $per_page);

        if(isset($_GET['page']) && is_numeric($_GET['page']))
        {
            $show_page = $_GET['page'];

            if ($show_page > 0 && $show_page <= $total_pages)
            {
                $start = ($show_page - 1) * $per_page;
                $end = $start + $per_page;
            }
            else
            {
                $start = 0;
                $end = $per_page;
            }               

        }
        else
        {
            $start = 0;
            $end = $per_page;
        }


        //display paginations
        echo "<p> View pages: ";
        for ($i=1; $i < $total_pages; $i++)
        { 
            if (isset($_GET['page']) && $_GET['page'] == $i)
            {
                echo  $i . " ";
            }
            else
            {
                echo "<a href='view-pag.php?$i'>" . $i . "</a> | ";
            }

        }
        echo "</p>";

    }
    else
    {
        echo "No result to display.";
    }

}
else
{
    echo "Error: " . $mysqli->error;
}


?>

Static methods - How to call a method from another method?

If these don't depend on the class or instance, then just make them a function.

As this would seem like the obvious solution. Unless of course you think it's going to need to be overwritten, subclassed, etc. If so, then the previous answers are the best bet. Fingers crossed I won't get marked down for merely offering an alternative solution that may or may not fit someone’s needs ;).

As the correct answer will depend on the use case of the code in question ;)

Where should I put <script> tags in HTML markup?

XHTML Won't Validate if the script is anywhere other than within the head element. turns out it can be everywhere.

You can defer the execution with something like jQuery so it doesn't matter where it's placed (except for a small performance hit during parsing).

How to access Anaconda command prompt in Windows 10 (64-bit)

I added "\Anaconda3_64\" and "\Anaconda3_64\Scripts\" to the PATH variable. Then I can use conda from powershell or command prompt.

Query for array elements inside JSON type

jsonb in Postgres 9.4+

You can use the same query as below, just with jsonb_array_elements().

But rather use the jsonb "contains" operator @> in combination with a matching GIN index on the expression data->'objects':

CREATE INDEX reports_data_gin_idx ON reports
USING gin ((data->'objects') jsonb_path_ops);

SELECT * FROM reports WHERE data->'objects' @> '[{"src":"foo.png"}]';

Since the key objects holds a JSON array, we need to match the structure in the search term and wrap the array element into square brackets, too. Drop the array brackets when searching a plain record.

More explanation and options:

json in Postgres 9.3+

Unnest the JSON array with the function json_array_elements() in a lateral join in the FROM clause and test for its elements:

SELECT data::text, obj
FROM   reports r, json_array_elements(r.data#>'{objects}') obj
WHERE  obj->>'src' = 'foo.png';

db<>fiddle here
Old sqlfiddle

The CTE (WITH query) just substitutes for a table reports.
Or, equivalent for just a single level of nesting:

SELECT *
FROM   reports r, json_array_elements(r.data->'objects') obj
WHERE  obj->>'src' = 'foo.png';

->>, -> and #> operators are explained in the manual.

Both queries use an implicit JOIN LATERAL.

Closely related:

Is there a way to get colored text in GitHubflavored Markdown?

You cannot include style directives in GFM.

The most complete documentation/example is "Markdown Cheatsheet", and it illustrates that this element <style> is missing.

If you manage to include your text in one of the GFM elements, then you can play with a github.css stylesheet in order to colors that way, meaning to color using inline CSS style directives, referring to said css stylesheet.

Count number of occurrences for each unique value

select time, coalesce(count(case when activities = 3 then 1 end), 0) as count
from MyTable
group by time

SQL Fiddle Example

Output:

|  TIME | COUNT |
-----------------
| 13:00 |     2 |
| 13:15 |     2 |
| 13:30 |     0 |
| 13:45 |     1 |

If you want to count all the activities in one query, you can do:

select time, 
    coalesce(count(case when activities = 1 then 1 end), 0) as count1,
    coalesce(count(case when activities = 2 then 1 end), 0) as count2,
    coalesce(count(case when activities = 3 then 1 end), 0) as count3,
    coalesce(count(case when activities = 4 then 1 end), 0) as count4,
    coalesce(count(case when activities = 5 then 1 end), 0) as count5
from MyTable
group by time

The advantage of this over grouping by activities, is that it will return a count of 0 even if there are no activites of that type for that time segment.

Of course, this will not return rows for time segments with no activities of any type. If you need that, you'll need to use a left join with table that lists all the possible time segments.

PDOException “could not find driver”

The solution for me was in the instalation of php, Dont have correctly configured the environment variable and the php.ini file. Doing this two correction an uncomented de line of extension = pdo_mysql.so works

SHA512 vs. Blowfish and Bcrypt

It should suffice to say whether bcrypt or SHA-512 (in the context of an appropriate algorithm like PBKDF2) is good enough. And the answer is yes, either algorithm is secure enough that a breach will occur through an implementation flaw, not cryptanalysis.

If you insist on knowing which is "better", SHA-512 has had in-depth reviews by NIST and others. It's good, but flaws have been recognized that, while not exploitable now, have led to the the SHA-3 competition for new hash algorithms. Also, keep in mind that the study of hash algorithms is "newer" than that of ciphers, and cryptographers are still learning about them.

Even though bcrypt as a whole hasn't had as much scrutiny as Blowfish itself, I believe that being based on a cipher with a well-understood structure gives it some inherent security that hash-based authentication lacks. Also, it is easier to use common GPUs as a tool for attacking SHA-2–based hashes; because of its memory requirements, optimizing bcrypt requires more specialized hardware like FPGA with some on-board RAM.


Note: bcrypt is an algorithm that uses Blowfish internally. It is not an encryption algorithm itself. It is used to irreversibly obscure passwords, just as hash functions are used to do a "one-way hash".

Cryptographic hash algorithms are designed to be impossible to reverse. In other words, given only the output of a hash function, it should take "forever" to find a message that will produce the same hash output. In fact, it should be computationally infeasible to find any two messages that produce the same hash value. Unlike a cipher, hash functions aren't parameterized with a key; the same input will always produce the same output.

If someone provides a password that hashes to the value stored in the password table, they are authenticated. In particular, because of the irreversibility of the hash function, it's assumed that the user isn't an attacker that got hold of the hash and reversed it to find a working password.

Now consider bcrypt. It uses Blowfish to encrypt a magic string, using a key "derived" from the password. Later, when a user enters a password, the key is derived again, and if the ciphertext produced by encrypting with that key matches the stored ciphertext, the user is authenticated. The ciphertext is stored in the "password" table, but the derived key is never stored.

In order to break the cryptography here, an attacker would have to recover the key from the ciphertext. This is called a "known-plaintext" attack, since the attack knows the magic string that has been encrypted, but not the key used. Blowfish has been studied extensively, and no attacks are yet known that would allow an attacker to find the key with a single known plaintext.

So, just like irreversible algorithms based cryptographic digests, bcrypt produces an irreversible output, from a password, salt, and cost factor. Its strength lies in Blowfish's resistance to known plaintext attacks, which is analogous to a "first pre-image attack" on a digest algorithm. Since it can be used in place of a hash algorithm to protect passwords, bcrypt is confusingly referred to as a "hash" algorithm itself.

Assuming that rainbow tables have been thwarted by proper use of salt, any truly irreversible function reduces the attacker to trial-and-error. And the rate that the attacker can make trials is determined by the speed of that irreversible "hash" algorithm. If a single iteration of a hash function is used, an attacker can make millions of trials per second using equipment that costs on the order of $1000, testing all passwords up to 8 characters long in a few months.

If however, the digest output is "fed back" thousands of times, it will take hundreds of years to test the same set of passwords on that hardware. Bcrypt achieves the same "key strengthening" effect by iterating inside its key derivation routine, and a proper hash-based method like PBKDF2 does the same thing; in this respect, the two methods are similar.

So, my recommendation of bcrypt stems from the assumptions 1) that a Blowfish has had a similar level of scrutiny as the SHA-2 family of hash functions, and 2) that cryptanalytic methods for ciphers are better developed than those for hash functions.

How to check if JSON return is empty with jquery

Below code(jQuery.isEmptyObject(anyObject) function is already provided) works perfectly fine, no need to write one of your own.

   // works for any Object Including JSON(key value pair) or Array.
  //  var arr = [];
  //  var jsonObj = {};
    if (jQuery.isEmptyObject(anyObjectIncludingJSON))
    {
       console.log("Empty Object");
    }

Python 3 turn range to a list

Use Range in Python 3.

Here is a example function that return in between numbers from two numbers

def get_between_numbers(a, b):
    """
    This function will return in between numbers from two numbers.
    :param a:
    :param b:
    :return:
    """
    x = []
    if b < a:
        x.extend(range(b, a))
        x.append(a)
    else:
        x.extend(range(a, b))
        x.append(b)

    return x

Result

print(get_between_numbers(5, 9))
print(get_between_numbers(9, 5))

[5, 6, 7, 8, 9]  
[5, 6, 7, 8, 9]

How to create a DataFrame of random integers with Pandas?

The recommended way to create random integers with NumPy these days is to use numpy.random.Generator.integers. (documentation)

import numpy as np
import pandas as pd

rng = np.random.default_rng()
df = pd.DataFrame(rng.integers(0, 100, size=(100, 4)), columns=list('ABCD'))
df
----------------------
      A    B    C    D
 0   58   96   82   24
 1   21    3   35   36
 2   67   79   22   78
 3   81   65   77   94
 4   73    6   70   96
... ...  ...  ...  ...
95   76   32   28   51
96   33   68   54   77
97   76   43   57   43
98   34   64   12   57
99   81   77   32   50
100 rows × 4 columns

Java converting Image to BufferedImage

One way to handle this is to create a new BufferedImage, and tell it's graphics object to draw your scaled image into the new BufferedImage:

final float FACTOR  = 4f;
BufferedImage img = ImageIO.read(new File("graphic.png"));
int scaleX = (int) (img.getWidth() * FACTOR);
int scaleY = (int) (img.getHeight() * FACTOR);
Image image = img.getScaledInstance(scaleX, scaleY, Image.SCALE_SMOOTH);
BufferedImage buffered = new BufferedImage(scaleX, scaleY, TYPE);
buffered.getGraphics().drawImage(image, 0, 0 , null);

That should do the trick without casting.

How to get VM arguments from inside of Java application?

I haven't tried specifically getting the VM settings, but there is a wealth of information in the JMX utilities specifically the MXBean utilities. This would be where I would start. Hopefully you find something there to help you.

The sun website has a bunch on the technology:

http://java.sun.com/javase/6/docs/technotes/guides/management/mxbeans.html

Android: adb: Permission Denied

Without rooting: If you can't root your phone, use the run-as <package> command to be able to access data of your application.

Example:

$ adb exec-out run-as com.yourcompany.app ls -R /data/data/com.yourcompany.app/

exec-out executes the command without starting a shell and mangling the output.

Could not load file or assembly 'log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=692fbea5521e1304'

To configure IIS to run 32-bit applications you must follow these steps:

Open IIS Go to current server – > Application Pools Select the application pool your 32-bit application will run under Click Advanced setting or Application Pool Default Set Enable 32-bit Applications to True

This solution worked for me, thanks.

How do I install opencv using pip?

There are two options-

pip install cv2 

or

pip install opencv-python

Hope it helps.

HTTPS connection Python

Why haven't you tried httplib.HTTPSConnection? It doesn't do SSL validation but this isn't required to connect over https. Your code works fine with https connection:

>>> import httplib
>>> conn = httplib.HTTPSConnection("mail.google.com")
>>> conn.request("GET", "/")
>>> r1 = conn.getresponse()
>>> print r1.status, r1.reason
200 OK

MySQL Error 1215: Cannot add foreign key constraint

For others same error may not always be due to column type mismatch, you can find out more information about a mysql foriegn key error by issuing command

SHOW ENGINE INNODB STATUS;

you may find a error near the top of the printed message something like

Cannot find an index in the referenced table where the referenced columns appear as the first columns, or column types in the table and the referenced table do not match for constraint.

Why am I getting error CS0246: The type or namespace name could not be found?

Edit: Oh ignore me, you're not using Visual Studio.

Have you added the reference to your project?

As in this sort of thing:

enter image description here

How do you load custom UITableViewCells from Xib files?

Here are two methods which the original author states was recommended by an IB engineer.

See the actual post for more details. I prefer method #2 as it seems simpler.

Method #1:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"BDCustomCell"];
    if (cell == nil) {
        // Create a temporary UIViewController to instantiate the custom cell.
        UIViewController *temporaryController = [[UIViewController alloc] initWithNibName:@"BDCustomCell" bundle:nil];
        // Grab a pointer to the custom cell.
        cell = (BDCustomCell *)temporaryController.view;
        [[cell retain] autorelease];
        // Release the temporary UIViewController.
        [temporaryController release];
    }

    return cell;
}

Method #2:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"BDCustomCell"];
    if (cell == nil) {
        // Load the top-level objects from the custom cell XIB.
        NSArray *topLevelObjects = [[NSBundle mainBundle] loadNibNamed:@"BDCustomCell" owner:self options:nil];
        // Grab a pointer to the first object (presumably the custom cell, as that's all the XIB should contain).
        cell = [topLevelObjects objectAtIndex:0];
    }

    return cell;
}

Update (2014): Method #2 is still valid but there is no documentation for it anymore. It used to be in the official docs but is now removed in favor of storyboards.

I posted a working example on Github:
https://github.com/bentford/NibTableCellExample

edit for Swift 4.2

override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.
    self.tblContacts.register(UINib(nibName: CellNames.ContactsCell, bundle: nil), forCellReuseIdentifier: MyIdentifier)
}

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

    let cell = tableView.dequeueReusableCell(withIdentifier: MyIdentifier, for: indexPath) as! ContactsCell

    return cell
}

Java FileOutputStream Create File if not exists

File f = new File("Test.txt");
if(!f.exists()){
  f.createNewFile();
}else{
  System.out.println("File already exists");
}

Pass this f to your FileOutputStream constructor.

How to Disable GUI Button in Java

Once you've created the frame the part of the code with your conditional isn't going to get entered. To put it another way, at the time you execute the test if (btn1Clicked == true) , the button has not only not been clicked yet, it hasn't even been displayed to the user.

Lose the booleans and move the line with the btnConvertDocuments.setEnabled(false) into your actionListener. Make the buttons instance variables, do not make them static variables. (Alternatively you could keep the buttons as local variables and assign each of them their own anonymous inner class listener.)

How to create a delay in Swift?

If you need to set a delay of less than a second, it is not necessary to set the .seconds parameter. I hope this is useful to someone.

DispatchQueue.main.asyncAfter(deadline: .now() + 0.5, execute: {
        // your code hear
})

How do you stash an untracked file?

I was able to stash just the untracked files by doing:

git stash save "tracked files I'm working on"
git stash save -u "untracked files I'm trying to stash"
git stash pop stash@{1}

The last one pops the stash of the tracked files, thus leaving only the untracked files stashed.

serialize/deserialize java 8 java.time with Jackson JSON mapper

Update: Leaving this answer for historical reasons, but I don't recommend it. Please see the accepted answer above.

Tell Jackson to map using your custom [de]serialization classes:

@JsonSerialize(using = LocalDateTimeSerializer.class)
@JsonDeserialize(using = LocalDateTimeDeserializer.class)
private LocalDateTime ignoreUntil;

provide custom classes:

public class LocalDateTimeSerializer extends JsonSerializer<LocalDateTime> {
    @Override
    public void serialize(LocalDateTime arg0, JsonGenerator arg1, SerializerProvider arg2) throws IOException {
        arg1.writeString(arg0.toString());
    }
}

public class LocalDateTimeDeserializer extends JsonDeserializer<LocalDateTime> {
    @Override
    public LocalDateTime deserialize(JsonParser arg0, DeserializationContext arg1) throws IOException {
        return LocalDateTime.parse(arg0.getText());
    }
}

random fact: if i nest above classes and don't make them static, the error message is weird: org.springframework.web.HttpMediaTypeNotSupportedException: Content type 'application/json;charset=UTF-8' not supported

Bash Templating: How to build configuration files from templates with Bash?

Here is another solution: generate a bash script with all the variables and the contents of the template file, that script would look like this:

word=dog           
i=1                
cat << EOF         
the number is ${i} 
the word is ${word}

EOF                

If we feed this script into bash it would produce the desired output:

the number is 1
the word is dog

Here is how to generate that script and feed that script into bash:

(
    # Variables
    echo word=dog
    echo i=1

    # add the template
    echo "cat << EOF"
    cat template.txt
    echo EOF
) | bash

Discussion

  • The parentheses opens a sub shell, its purpose is to group together all the output generated
  • Within the sub shell, we generate all the variable declarations
  • Also in the sub shell, we generate the cat command with HEREDOC
  • Finally, we feed the sub shell output to bash and produce the desired output
  • If you want to redirect this output into a file, replace the last line with:

    ) | bash > output.txt
    

Sys is undefined

In case none of the above works for you, and you happen to be overriding OnPreRenderComplete, make sure you call base.OnPreRenderComplete. My therapist is going to be happy to see me back

REST API Best practices: Where to put parameters?

I generally tend towards #2, As a query argument (i.e. /api/resource?parameter=value ).

A third option is to actually post the parameter=value in the body.

This is because it works better for multi parameter resources and is more extendable for future use.

No matter which one you pick, make sure you only pick one, don't mix and match. That leads towards a confusing API.

What is C# analog of C++ std::pair?

Tuples are available since .NET4.0 and support generics:

Tuple<string, int> t = new Tuple<string, int>("Hello", 4);

In previous versions you can use System.Collections.Generic.KeyValuePair<K, V> or a solution like the following:

public class Pair<T, U> {
    public Pair() {
    }

    public Pair(T first, U second) {
        this.First = first;
        this.Second = second;
    }

    public T First { get; set; }
    public U Second { get; set; }
};

And use it like this:

Pair<String, int> pair = new Pair<String, int>("test", 2);
Console.WriteLine(pair.First);
Console.WriteLine(pair.Second);

This outputs:

test
2

Or even this chained pairs:

Pair<Pair<String, int>, bool> pair = new Pair<Pair<String, int>, bool>();
pair.First = new Pair<String, int>();
pair.First.First = "test";
pair.First.Second = 12;
pair.Second = true;

Console.WriteLine(pair.First.First);
Console.WriteLine(pair.First.Second);
Console.WriteLine(pair.Second);

That outputs:

test
12
true

Undefined reference to sqrt (or other mathematical functions)

You may find that you have to link with the math libraries on whatever system you're using, something like:

gcc -o myprog myprog.c -L/path/to/libs -lm
                                       ^^^ - this bit here.

Including headers lets a compiler know about function declarations but it does not necessarily automatically link to the code required to perform that function.

Failing that, you'll need to show us your code, your compile command and the platform you're running on (operating system, compiler, etc).

The following code compiles and links fine:

#include <math.h>
int main (void) {
    int max = sqrt (9);
    return 0;
}

Just be aware that some compilation systems depend on the order in which libraries are given on the command line. By that, I mean they may process the libraries in sequence and only use them to satisfy unresolved symbols at that point in the sequence.

So, for example, given the commands:

gcc -o plugh plugh.o -lxyzzy
gcc -o plugh -lxyzzy plugh.o

and plugh.o requires something from the xyzzy library, the second may not work as you expect. At the point where you list the library, there are no unresolved symbols to satisfy.

And when the unresolved symbols from plugh.o do appear, it's too late.

What is a callback?

A callback is a function pointer that you pass in to another function. The function you are calling will 'callback' (execute) the other function when it has completed.

Check out this link.

How to change background color of cell in table using java script

Try this:

function btnClick() {
    var x = document.getElementById("mytable").getElementsByTagName("td");
    x[0].innerHTML = "i want to change my cell color";
    x[0].style.backgroundColor = "yellow";            
}

Set from JS, backgroundColor is the equivalent of background-color in your style-sheet.

Note also that the .cells collection belongs to a table row, not to the table itself. To get all the cells from all rows you can instead use getElementsByTagName().

Demo: http://jsbin.com/ekituv/edit#preview

Change the image source on rollover using jQuery

I know you're asking about using jQuery, but you can achieve the same effect in browsers that have JavaScript turned off using CSS:

#element {
    width: 100px; /* width of image */
    height: 200px; /* height of image */
    background-image: url(/path/to/image.jpg);
}

#element:hover {
    background-image: url(/path/to/other_image.jpg);
}

There's a longer description here

Even better, however, is to use sprites: simple-css-image-rollover

How do I export an Android Studio project?

Apparently, there's a lot of "dead wood" in the "build" directories of a project.

Under linux/unix, a simple way to get a clean, private backup is to use the "tar" command along with the "--exclude=String" option.

For example, to create an archive of all my apps while excluding the build directories, I have a script that creates the following 2 commands :

cd $HOME/android/Studio
tar cvf MyBackup-2017-07-13.tar Projects --exclude=build

MySQL CONCAT returns NULL if any field contain NULL

you can use if statement like below

select CONCAT(if(affiliate_name is null ,'',affiliate_name),'- ',if(model is null ,'',affiliate_name)) as model from devices

./configure : /bin/sh^M : bad interpreter

Use the dos2unix command in linux to convert the saved file. example :

dos2unix file_name

Laravel 5 not finding css files

If you are using laravel 5 or 6:

  1. Inside Public folder create .css, .js, images... folders

enter image description here

  1. Then inside your blade file you can display an images using this code :

_x000D_
_x000D_
<link rel="stylesheet" href="/css/bootstrap.min.css">
<link src="/images/test.png">
<!-- / is important and dont write public folder-->
_x000D_
_x000D_
_x000D_

Smart cast to 'Type' is impossible, because 'variable' is a mutable property that could have been changed by this time

The practical reason why this doesn't work is not related to threads. The point is that node.left is effectively translated into node.getLeft().

This property getter might be defined as:

val left get() = if (Math.random() < 0.5) null else leftPtr

Therefore two calls might not return the same result.

Entity Framework Core add unique constraint code-first

Solution for EF Core

public class User
{
    public int Id { get; set; }
    public string Name { get; set; }
    public string Passport { get; set; }
}

public class ApplicationContext : DbContext
{
    public DbSet<User> Users { get; set; }
    public ApplicationContext()
    {
        Database.EnsureCreated();
    }
    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        optionsBuilder.UseSqlServer(@"Server=(localdb)\mssqllocaldb;Database=efbasicsappdb;Trusted_Connection=True;");
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<User>().HasAlternateKey(u => u.Passport);
        //or: modelBuilder.Entity<User>().HasAlternateKey(u => new { u.Passport, u.Name})
    }
}

DB table will look like this:

CREATE TABLE [dbo].[Users] (
    [Id]       INT            IDENTITY (1, 1) NOT NULL,
    [Name]     NVARCHAR (MAX) NULL,
    [Passport] NVARCHAR (450) NOT NULL,
    CONSTRAINT [PK_Users] PRIMARY KEY CLUSTERED ([Id] ASC),
    CONSTRAINT [AK_Users_Passport] UNIQUE NONCLUSTERED ([Passport] ASC)
);

Ref to EF Core docs

Getting the exception value in Python

For python2, It's better to use e.message to get the exception message, this will avoid possible UnicodeDecodeError. But yes e.message will be empty for some kind of exceptions like OSError, in which case we can add a exc_info=True to our logging function to not miss the error.
For python3, I think it's safe to use str(e).

Export specific rows from a PostgreSQL table as INSERT SQL script

For my use-case I was able to simply pipe to grep.

pg_dump -U user_name --data-only --column-inserts -t nyummy.cimory | grep "tokyo" > tokyo.sql

How do I find out which settings.xml file maven is using

Use the Maven debug option, ie mvn -X :

Apache Maven 3.0.3 (r1075438; 2011-02-28 18:31:09+0100)
Maven home: /usr/java/apache-maven-3.0.3
Java version: 1.6.0_12, vendor: Sun Microsystems Inc.
Java home: /usr/java/jdk1.6.0_12/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "2.6.32-32-generic", arch: "i386", family: "unix"
[INFO] Error stacktraces are turned on.
[DEBUG] Reading global settings from /usr/java/apache-maven-3.0.3/conf/settings.xml
[DEBUG] Reading user settings from /home/myhome/.m2/settings.xml
...

In this output, you can see that the settings.xml is loaded from /home/myhome/.m2/settings.xml.

What is the proper declaration of main in C++?

From Standard docs., 3.6.1.2 Main Function,

It shall have a return type of type int, but otherwise its type is implementation-defined. All implementations shall allow both of the following definitions of main:

int main() { / ... / } and int main(int argc, char* argv[]) { / ... / }

In the latter form argc shall be the number of arguments passed to the program from the environment in which the program is run.If argc is nonzero these arguments shall be supplied in argv[0] through argv[argc-1] as pointers to the initial characters of null-terminated multibyte strings.....

Hope that helps..

Changing the Status Bar Color for specific ViewControllers using Swift in iOS8

In Swift 4 or 4.2

You can add on your vc

preferredStatusBarStyle

and set return value to

.lightContent or .default

ex:

override var preferredStatusBarStyle: UIStatusBarStyle {
        return .lightContent
}

How to add a Java Properties file to my Java Project in Eclipse

  1. Create Folder “resources” under Java Resources folder if your project doesn’t have it.
    1. create config.properties file with below value.

enter image description here

/Java Resources/resources/config.properties

for loading properties.

Properties prop = new Properties();
InputStream input = null;

try {

      input = getClass().getClassLoader().getResourceAsStream("config.properties");


    // load a properties file
    prop.load(input);

    // get the property value and print it out
    System.out.println(prop.getProperty("database"));
    System.out.println(prop.getProperty("dbuser"));
    System.out.println(prop.getProperty("dbpassword"));

} catch (IOException ex) {
    ex.printStackTrace();
} finally {
    if (input != null) {
        try {
            input.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

phpinfo() is not working on my CentOS server

Save the page which contains

<?php
    phpinfo();
?>

with the .php extension. Something like info.php, not info.html...

The type or namespace cannot be found (are you missing a using directive or an assembly reference?)

You don't have the namespace the Login class is in as a reference.

Add the following to the form that uses the Login class:

using FootballLeagueSystem;

When you want to use a class in another namespace, you have to tell the compiler where to find it. In this case, Login is inside the FootballLeagueSystem namespace, or : FootballLeagueSystem.Login is the fully qualified namespace.

As a commenter pointed out, you declare the Login class inside the FootballLeagueSystem namespace, but you're using it in the FootballLeague namespace.

jQuery validation: change default error message

instead of these custom error messages we can specify the type of the text field.

Ex: set type of the field in to type = 'email'

then plugin will identify the field and validate correctly.

OpenCV get pixel channel value from Mat image

Assuming the type is CV_8UC3 you would do this:

for(int i = 0; i < foo.rows; i++)
{
    for(int j = 0; j < foo.cols; j++)
    {
        Vec3b bgrPixel = foo.at<Vec3b>(i, j);

        // do something with BGR values...
    }
}

Here is the documentation for Vec3b. Hope that helps! Also, don't forget OpenCV stores things internally as BGR not RGB.

EDIT :
For performance reasons, you may want to use direct access to the data buffer in order to process the pixel values:

Here is how you might go about this:

uint8_t* pixelPtr = (uint8_t*)foo.data;
int cn = foo.channels();
Scalar_<uint8_t> bgrPixel;

for(int i = 0; i < foo.rows; i++)
{
    for(int j = 0; j < foo.cols; j++)
    {
        bgrPixel.val[0] = pixelPtr[i*foo.cols*cn + j*cn + 0]; // B
        bgrPixel.val[1] = pixelPtr[i*foo.cols*cn + j*cn + 1]; // G
        bgrPixel.val[2] = pixelPtr[i*foo.cols*cn + j*cn + 2]; // R

        // do something with BGR values...
    }
}

Or alternatively:

int cn = foo.channels();
Scalar_<uint8_t> bgrPixel;

for(int i = 0; i < foo.rows; i++)
{
    uint8_t* rowPtr = foo.row(i);
    for(int j = 0; j < foo.cols; j++)
    {
        bgrPixel.val[0] = rowPtr[j*cn + 0]; // B
        bgrPixel.val[1] = rowPtr[j*cn + 1]; // G
        bgrPixel.val[2] = rowPtr[j*cn + 2]; // R

        // do something with BGR values...
    }
}

Change application's starting activity

 <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

Subtract two variables in Bash

Try this Bash syntax instead of trying to use an external program expr:

count=$((FIRSTV-SECONDV))

BTW, the correct syntax of using expr is:

count=$(expr $FIRSTV - $SECONDV)

But keep in mind using expr is going to be slower than the internal Bash syntax I provided above.

Undo a particular commit in Git that's been pushed to remote repos

I don't like the auto-commit that git revert does, so this might be helpful for some.

If you just want the modified files not the auto-commit, you can use --no-commit

% git revert --no-commit <commit hash>

which is the same as the -n

% git revert -n <commit hash>

Android and setting alpha for (image) view alpha

use android:alpha=0.5 to achieve the opacity of 50% and to turn Android Material icons from Black to Grey.

Where do I find some good examples for DDD?

This is a good example based on domain driven design and explains why it is important to have separate domain layer.
Microsoft spain - DDD N Layer Architecture

How to find current transaction level?

just run DBCC useroptions and you'll get something like this:

Set Option                  Value
--------------------------- --------------
textsize                    2147483647
language                    us_english
dateformat                  mdy
datefirst                   7
lock_timeout                -1
quoted_identifier           SET
arithabort                  SET
ansi_null_dflt_on           SET
ansi_warnings               SET
ansi_padding                SET
ansi_nulls                  SET
concat_null_yields_null     SET
isolation level             read committed

php function mail() isn't working

I think you are not configured properly,

if you are using XAMPP then you can easily send mail from localhost.

for example you can configure C:\xampp\php\php.ini and c:\xampp\sendmail\sendmail.ini for gmail to send mail.

in C:\xampp\php\php.ini find extension=php_openssl.dll and remove the semicolon from the beginning of that line to make SSL working for gmail for localhost.

in php.ini file find [mail function] and change

SMTP=smtp.gmail.com
smtp_port=587
sendmail_from = [email protected]
sendmail_path = "C:\xampp\sendmail\sendmail.exe -t"

(use the above send mail path only and it will work)

Now Open C:\xampp\sendmail\sendmail.ini. Replace all the existing code in sendmail.ini with following code

[sendmail]

smtp_server=smtp.gmail.com
smtp_port=587
error_logfile=error.log
debug_logfile=debug.log
[email protected]
auth_password=my-gmail-password
[email protected]

Now you have done!! create php file with mail function and send mail from localhost.

Update

First, make sure you PHP installation has SSL support (look for an "openssl" section in the output from phpinfo()).

You can set the following settings in your PHP.ini:

ini_set("SMTP","ssl://smtp.gmail.com");
ini_set("smtp_port","465");

Add JavaScript object to JavaScript object

jsonIssues = [...jsonIssues,{ID:'3',Name:'name 3',Notes:'NOTES 3'}]

How to use querySelectorAll only for elements that have a specific attribute set?

You can use querySelectorAll() like this:

var test = document.querySelectorAll('input[value][type="checkbox"]:not([value=""])');

This translates to:

get all inputs with the attribute "value" and has the attribute "value" that is not blank.

In this demo, it disables the checkbox with a non-blank value.

How can I use the MS JDBC driver with MS SQL Server 2008 Express?

If your databaseName value is correct, then use this: DriverManger.getconnection("jdbc:sqlserver://ServerIp:1433;user=myuser;password=mypassword;databaseName=databaseName;")

Group By Multiple Columns

Ok got this as:

var query = (from t in Transactions
             group t by new {t.MaterialID, t.ProductID}
             into grp
                    select new
                    {
                        grp.Key.MaterialID,
                        grp.Key.ProductID,
                        Quantity = grp.Sum(t => t.Quantity)
                    }).ToList();

How to see tomcat is running or not

open your browser,check whether Tomcat homepage is visible by below command.

http://ipaddress:portnumber

also check this

u'\ufeff' in Python string

Here is based on the answer from Mark Tolonen. The string included different languages of the word 'test' that's separated by '|', so you can see the difference.

u = u'ABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'
e8 = u.encode('utf-8')        # encode without BOM
e8s = u.encode('utf-8-sig')   # encode with BOM
e16 = u.encode('utf-16')      # encode with BOM
e16le = u.encode('utf-16le')  # encode without BOM
e16be = u.encode('utf-16be')  # encode without BOM
print('utf-8     %r' % e8)
print('utf-8-sig %r' % e8s)
print('utf-16    %r' % e16)
print('utf-16le  %r' % e16le)
print('utf-16be  %r' % e16be)
print()
print('utf-8  w/ BOM decoded with utf-8     %r' % e8s.decode('utf-8'))
print('utf-8  w/ BOM decoded with utf-8-sig %r' % e8s.decode('utf-8-sig'))
print('utf-16 w/ BOM decoded with utf-16    %r' % e16.decode('utf-16'))
print('utf-16 w/ BOM decoded with utf-16le  %r' % e16.decode('utf-16le'))

Here is a test run:

>>> u = u'ABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'
>>> e8 = u.encode('utf-8')        # encode without BOM
>>> e8s = u.encode('utf-8-sig')   # encode with BOM
>>> e16 = u.encode('utf-16')      # encode with BOM
>>> e16le = u.encode('utf-16le')  # encode without BOM
>>> e16be = u.encode('utf-16be')  # encode without BOM
>>> print('utf-8     %r' % e8)
utf-8     b'ABCtest\xce\xb2\xe8\xb2\x9d\xe5\xa1\x94\xec\x9c\x84m\xc3\xa1sb\xc3\xaata|test|\xd8\xa7\xd8\xae\xd8\xaa\xd8\xa8\xd8\xa7\xd8\xb1|\xe6\xb5\x8b\xe8\xaf\x95|\xe6\xb8\xac\xe8\xa9\xa6|\xe3\x83\x86\xe3\x82\xb9\xe3\x83\x88|\xe0\xa4\xaa\xe0\xa4\xb0\xe0\xa5\x80\xe0\xa4\x95\xe0\xa5\x8d\xe0\xa4\xb7\xe0\xa4\xbe|\xe0\xb4\xaa\xe0\xb4\xb0\xe0\xb4\xbf\xe0\xb4\xb6\xe0\xb5\x8b\xe0\xb4\xa7\xe0\xb4\xa8|\xd7\xa4\xd6\xbc\xd7\xa8\xd7\x95\xd7\x91\xd7\x99\xd7\xa8\xd7\x9f|ki\xe1\xbb\x83m tra|\xc3\x96l\xc3\xa7ek|'
>>> print('utf-8-sig %r' % e8s)
utf-8-sig b'\xef\xbb\xbfABCtest\xce\xb2\xe8\xb2\x9d\xe5\xa1\x94\xec\x9c\x84m\xc3\xa1sb\xc3\xaata|test|\xd8\xa7\xd8\xae\xd8\xaa\xd8\xa8\xd8\xa7\xd8\xb1|\xe6\xb5\x8b\xe8\xaf\x95|\xe6\xb8\xac\xe8\xa9\xa6|\xe3\x83\x86\xe3\x82\xb9\xe3\x83\x88|\xe0\xa4\xaa\xe0\xa4\xb0\xe0\xa5\x80\xe0\xa4\x95\xe0\xa5\x8d\xe0\xa4\xb7\xe0\xa4\xbe|\xe0\xb4\xaa\xe0\xb4\xb0\xe0\xb4\xbf\xe0\xb4\xb6\xe0\xb5\x8b\xe0\xb4\xa7\xe0\xb4\xa8|\xd7\xa4\xd6\xbc\xd7\xa8\xd7\x95\xd7\x91\xd7\x99\xd7\xa8\xd7\x9f|ki\xe1\xbb\x83m tra|\xc3\x96l\xc3\xa7ek|'
>>> print('utf-16    %r' % e16)
utf-16    b"\xff\xfeA\x00B\x00C\x00t\x00e\x00s\x00t\x00\xb2\x03\x9d\x8cTX\x04\xc7m\x00\xe1\x00s\x00b\x00\xea\x00t\x00a\x00|\x00t\x00e\x00s\x00t\x00|\x00'\x06.\x06*\x06(\x06'\x061\x06|\x00Km\xd5\x8b|\x00,nf\x8a|\x00\xc60\xb90\xc80|\x00*\t0\t@\t\x15\tM\t7\t>\t|\x00*\r0\r?\r6\rK\r'\r(\r|\x00\xe4\x05\xbc\x05\xe8\x05\xd5\x05\xd1\x05\xd9\x05\xe8\x05\xdf\x05|\x00k\x00i\x00\xc3\x1em\x00 \x00t\x00r\x00a\x00|\x00\xd6\x00l\x00\xe7\x00e\x00k\x00|\x00"
>>> print('utf-16le  %r' % e16le)
utf-16le  b"A\x00B\x00C\x00t\x00e\x00s\x00t\x00\xb2\x03\x9d\x8cTX\x04\xc7m\x00\xe1\x00s\x00b\x00\xea\x00t\x00a\x00|\x00t\x00e\x00s\x00t\x00|\x00'\x06.\x06*\x06(\x06'\x061\x06|\x00Km\xd5\x8b|\x00,nf\x8a|\x00\xc60\xb90\xc80|\x00*\t0\t@\t\x15\tM\t7\t>\t|\x00*\r0\r?\r6\rK\r'\r(\r|\x00\xe4\x05\xbc\x05\xe8\x05\xd5\x05\xd1\x05\xd9\x05\xe8\x05\xdf\x05|\x00k\x00i\x00\xc3\x1em\x00 \x00t\x00r\x00a\x00|\x00\xd6\x00l\x00\xe7\x00e\x00k\x00|\x00"
>>> print('utf-16be  %r' % e16be)
utf-16be  b"\x00A\x00B\x00C\x00t\x00e\x00s\x00t\x03\xb2\x8c\x9dXT\xc7\x04\x00m\x00\xe1\x00s\x00b\x00\xea\x00t\x00a\x00|\x00t\x00e\x00s\x00t\x00|\x06'\x06.\x06*\x06(\x06'\x061\x00|mK\x8b\xd5\x00|n,\x8af\x00|0\xc60\xb90\xc8\x00|\t*\t0\t@\t\x15\tM\t7\t>\x00|\r*\r0\r?\r6\rK\r'\r(\x00|\x05\xe4\x05\xbc\x05\xe8\x05\xd5\x05\xd1\x05\xd9\x05\xe8\x05\xdf\x00|\x00k\x00i\x1e\xc3\x00m\x00 \x00t\x00r\x00a\x00|\x00\xd6\x00l\x00\xe7\x00e\x00k\x00|"
>>> print()

>>> print('utf-8  w/ BOM decoded with utf-8     %r' % e8s.decode('utf-8'))
utf-8  w/ BOM decoded with utf-8     '\ufeffABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'
>>> print('utf-8  w/ BOM decoded with utf-8-sig %r' % e8s.decode('utf-8-sig'))
utf-8  w/ BOM decoded with utf-8-sig 'ABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'
>>> print('utf-16 w/ BOM decoded with utf-16    %r' % e16.decode('utf-16'))
utf-16 w/ BOM decoded with utf-16    'ABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'
>>> print('utf-16 w/ BOM decoded with utf-16le  %r' % e16.decode('utf-16le'))
utf-16 w/ BOM decoded with utf-16le  '\ufeffABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'

It's worth to know that only both utf-8-sig and utf-16 get back the original string after both encode and decode.

The value violated the integrity constraints for the column

You can replace the values "null" from the original file & field/column.

How to use \n new line in VB msgbox() ...?

Module MyHelpers
    <Extension()>
    Public Function UnEscape(ByVal aString As String) As String

       Return Regex.Unescape(aString)

    End Function
End Module

Usage:

console.writeline("Ciao!\n".unEscape)

multiprocessing: How do I share a dict among multiple processes?

Maybe you can try pyshmht, sharing memory based hash table extension for Python.

Notice

  1. It's not fully tested, just for your reference.

  2. It currently lacks lock/sem mechanisms for multiprocessing.

Quadratic and cubic regression in Excel

I know that this question is a little old, but I thought that I would provide an alternative which, in my opinion, might be a little easier. If you're willing to add "temporary" columns to a data set, you can use Excel's Analysis ToolPak?Data Analysis?Regression. The secret to doing a quadratic or a cubic regression analysis is defining the Input X Range:.

If you're doing a simple linear regression, all you need are 2 columns, X & Y. If you're doing a quadratic, you'll need X_1, X_2, & Y where X_1 is the x variable and X_2 is x^2; likewise, if you're doing a cubic, you'll need X_1, X_2, X_3, & Y where X_1 is the x variable, X_2 is x^2 and X_3 is x^3. Notice how the Input X Range is from A1 to B22, spanning 2 columns.

Input for Quadratic Regression Analysis in Excel

The following image the output of the regression analysis. I've highlighted the common outputs, including the R-Squared values and all the coefficients.

Coefficients of Quadratic Regression Analysis in Excel

String.format() to format double in java

There are many way you can do this. Those are given bellow:

Suppose your original number is given bellow: double number = 2354548.235;

Using NumberFormat and Rounding mode

NumberFormat nf = DecimalFormat.getInstance(Locale.ENGLISH);
    DecimalFormat decimalFormatter = (DecimalFormat) nf;
    decimalFormatter.applyPattern("#,###,###.##");
    decimalFormatter.setRoundingMode(RoundingMode.CEILING);

    String fString = decimalFormatter.format(number);
    System.out.println(fString);

Using String formatter

System.out.println(String.format("%1$,.2f", number));

In all cases the output will be: 2354548.24

Note:

During rounding you can add RoundingMode in your formatter. Here are some Rounding mode given bellow:

    decimalFormat.setRoundingMode(RoundingMode.CEILING);
    decimalFormat.setRoundingMode(RoundingMode.FLOOR);
    decimalFormat.setRoundingMode(RoundingMode.HALF_DOWN);
    decimalFormat.setRoundingMode(RoundingMode.HALF_UP);
    decimalFormat.setRoundingMode(RoundingMode.UP);

Here are the imports:

import java.math.BigDecimal;
import java.math.RoundingMode;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.util.Locale;

How to make div go behind another div?

You need to add z-index to the divs, with a positive number for the top div and negative for the div below

example

Creating csv file with php

Its blank because you are writing to file. you should write to output using php://output instead and also send header information to indicate that it's csv.

Example

header('Content-Type: text/csv');
header('Content-Disposition: attachment; filename="sample.csv"');
$data = array(
        'aaa,bbb,ccc,dddd',
        '123,456,789',
        '"aaa","bbb"'
);

$fp = fopen('php://output', 'wb');
foreach ( $data as $line ) {
    $val = explode(",", $line);
    fputcsv($fp, $val);
}
fclose($fp);

Recover sa password

The best way is to simply reset the password by connecting with a domain/local admin (so you may need help from your system administrators), but this only works if SQL Server was set up to allow local admins (these are now left off the default admin group during setup).

If you can't use this or other existing methods to recover / reset the SA password, some of which are explained here:

Then you could always backup your important databases, uninstall SQL Server, and install a fresh instance.

You can also search for less scrupulous ways to do it (e.g. there are password crackers that I am not enthusiastic about sharing).

As an aside, the login properties for sa would never say Windows Authentication. This is by design as this is a SQL Authentication account. This does not mean that Windows Authentication is disabled at the instance level (in fact it is not possible to do so), it just doesn't apply for a SQL auth account.

I wrote a tip on using PSExec to connect to an instance using the NT AUTHORITY\SYSTEM account (which works < SQL Server 2012), and a follow-up that shows how to hack the SqlWriter service (which can work on more modern versions):

And some other resources:

How to get span tag inside a div in jQuery and assign a text?

$("#message > span").text("your text");

or

$("#message").find("span").text("your text");

or

$("span","#message").text("your text");

or

$("#message > a.close-notify").siblings('span').text("your text");

COPY with docker but with exclusion

In my case, my Dockerfile contained an installation step, which produced the vendor directory (the PHP equivalent of node_modules). I then COPY this directory over to the final application image. Therefore, I could not put vendor in my .dockerignore. My solution was simply to delete the directory before performing composer install (the PHP equivalent of npm install).

FROM composer AS composer
WORKDIR /app
COPY . .
RUN rm -rf vendor \
    && composer install 

FROM richarvey/nginx-php-fpm
WORKDIR /var/www/html
COPY --from=composer /app .

This solution works and does not bloat the final image, but it is not ideal, because the vendor directory on the host is copied into the Docker context during the build process, which adds time.

Can't ping a local VM from the host

I had the same issue. Fixed it by adding a static route on my host to my VM via the VMnet8 adapter:

route ADD VM_addr MASK 255.255.255.255 VMnet8_addr

As previously mentioned, you need a bridged connection.

Apache redirect to another port

Apache supports name based and IP based virtual hosts. It looks like you are using both, which is probably not what you need.

I think you're actually trying to set up name-based virtual hosting, and for that you don't need to specify the IP address.

Try < VirtualHost *:80> to bind to all IP addresses, unless you really want ip based virtual hosting. This may be the case if the server has several IP addresses, and you want to serve different sites on different addresses. The most common setup is (I would guess) name based virtual hosts.

How to design RESTful search/filtering?

The best way to implement a RESTful search is to consider the search itself to be a resource. Then you can use the POST verb because you are creating a search. You do not have to literally create something in a database in order to use a POST.

For example:

Accept: application/json
Content-Type: application/json
POST http://example.com/people/searches
{
  "terms": {
    "ssn": "123456789"
  },
  "order": { ... },
  ...
}

You are creating a search from the user's standpoint. The implementation details of this are irrelevant. Some RESTful APIs may not even need persistence. That is an implementation detail.

Create Table from View

Select 
    MonthEndDate MED,  
    SUM(GrossBalance/1000000) GrossBalance,
    PortfolioRename PR 
into 
    testDynamic 
from 
    Risk_PortfolioOverview  
    Group By MonthEndDate, PortfolioRename

python xlrd unsupported format, or corrupt file.

I know there should be a proper way to solve it but just to save time

I uploaded my xlsx sheet to Google Sheets and then again downloaded it from Google Sheets it working now

If you don't have time to solve the problem, you can try this

How to disable textbox from editing?

The TextBox has a property called ReadOnly. If you set that property to true then the TextBox will still be able to scroll but the user wont be able to change the value.

What is "String args[]"? parameter in main method Java

String [] args is also how you declare an array of Strings in Java.

In this method signature, the array args will be filled with values when the method is called (as the other examples here show). Since you're learning though, it's worth understanding that this args array is just like if you created one yourself in a method, as in this:

public void foo() {
    String [] args = new String[2];
    args[0] = "hello";
    args[1] = "every";

    System.out.println("Output: " + args[0] + args[1]);

    // etc... the usage of 'args' here and in the main method is identical
}

how to remove untracked files in Git?

The command for your rescue is git clean.

Docker Repository Does Not Have a Release File on Running apt-get update on Ubuntu

On Linux Mint, the official instructions did not work for me. I had to go into /etc/apt/sources.list.d/additional-repositories.list and change serena to xenial.

SSLHandshakeException: No subject alternative names present

Thanks,Bruno for giving me heads up on Common Name and Subject Alternative Name. As we figured out certificate was generated with CN with DNS name of network and asked for regeneration of new certificate with Subject Alternative Name entry i.e. san=ip:10.0.0.1. which is the actual solution.

But, we managed to find out a workaround with which we can able to run on development phase. Just add a static block in the class from which we are making ssl connection.

static {
    HttpsURLConnection.setDefaultHostnameVerifier(new HostnameVerifier()
        {
            public boolean verify(String hostname, SSLSession session)
            {
                // ip address of the service URL(like.23.28.244.244)
                if (hostname.equals("23.28.244.244"))
                    return true;
                return false;
            }
        });
}

If you happen to be using Java 8, there is a much slicker way of achieving the same result:

static {
    HttpsURLConnection.setDefaultHostnameVerifier((hostname, session) -> hostname.equals("127.0.0.1"));
}

In Python, how do I split a string and keep the separators?

# This keeps all separators  in result 
##########################################################################
import re
st="%%(c+dd+e+f-1523)%%7"
sh=re.compile('[\+\-//\*\<\>\%\(\)]')

def splitStringFull(sh, st):
   ls=sh.split(st)
   lo=[]
   start=0
   for l in ls:
     if not l : continue
     k=st.find(l)
     llen=len(l)
     if k> start:
       tmp= st[start:k]
       lo.append(tmp)
       lo.append(l)
       start = k + llen
     else:
       lo.append(l)
       start =llen
   return lo
  #############################

li= splitStringFull(sh , st)
['%%(', 'c', '+', 'dd', '+', 'e', '+', 'f', '-', '1523', ')%%', '7']

How can I change image tintColor in iOS and WatchKit

If anyone care a solution without UIImageView:

// (Swift 3)
extension UIImage {
    func tint(with color: UIColor) -> UIImage {
        var image = withRenderingMode(.alwaysTemplate)
        UIGraphicsBeginImageContextWithOptions(size, false, scale)
        color.set()

        image.draw(in: CGRect(origin: .zero, size: size))
        image = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()
        return image
    }
}

Controlling Spacing Between Table Cells

Check this fiddle. You are going to need to take a look at using border-collapse and border-spacing. There are some quirks for IE (as usual). This is based on an answer to this question.

_x000D_
_x000D_
table.test td {
  background-color: lime;
  margin: 12px 12px 12px 12px;
  padding: 12px 12px 12px 12px;
}

table.test {
  border-collapse: separate;
  border-spacing: 10px;
  *border-collapse: expression('separate', cellSpacing='10px');
}
_x000D_
<table class="test">
  <tr>
    <td>Cell</td>
    <td>Cell</td>
    <td>Cell</td>
  </tr>
  <tr>
    <td>Cell</td>
    <td>Cell</td>
    <td>Cell</td>
  </tr>
  <tr>
    <td>Cell</td>
    <td>Cell</td>
    <td>Cell</td>
  </tr>
</table>
_x000D_
_x000D_
_x000D_

Silent installation of a MSI package

You should be able to use the /quiet or /qn options with msiexec to perform a silent install.

MSI packages export public properties, which you can set with the PROPERTY=value syntax on the end of the msiexec parameters.

For example, this command installs a package with no UI and no reboot, with a log and two properties:

msiexec /i c:\path\to\package.msi /quiet /qn /norestart /log c:\path\to\install.log PROPERTY1=value1 PROPERTY2=value2

You can read the options for msiexec by just running it with no options from Start -> Run.

Single quotes vs. double quotes in C or C++

A single quote is used for character, while double quotes are used for strings.

For example...

 printf("%c \n",'a');
 printf("%s","Hello World");

Output

a  
Hello World

If you used these in vice versa case and used a single quote for string and double quotes for a character, this will be the result:

  printf("%c \n","a");
  printf("%s",'Hello World');

output :

For the first line. You will get a garbage value or unexpected value or you may get an output like this:

?

While for the second statement, you will see nothing. One more thing, if you have more statements after this, they will also give you no result.

Note: PHP language gives you the flexibility to use single and double-quotes easily.

CSS Disabled scrolling

overflow-x: hidden;
would hide any thing on the x-axis that goes outside of the element, so there would be no need for the horizontal scrollbar and it get removed.

overflow-y: hidden;
would hide any thing on the y-axis that goes outside of the element, so there would be no need for the vertical scrollbar and it get removed.

overflow: hidden;
would remove both scrollbars

Check if process returns 0 with batch file

The project I'm working on, we do something like this. We use the errorlevel keyword so it kind of looks like:

call myExe.exe
if errorlevel 1 (
  goto build_fail
)

That seems to work for us. Note that you can put in multiple commands in the parens like an echo or whatever. Also note that build_fail is defined as:

:build_fail
echo ********** BUILD FAILURE **********
exit /b 1

Permutations between two lists of unequal length

The better answers to this only work for specific lengths of lists that are provided.

Here's a version that works for any lengths of input. It also makes the algorithm clear in terms of the mathematical concepts of combination and permutation.

from itertools import combinations, permutations
list1 = ['1', '2']
list2 = ['A', 'B', 'C']

num_elements = min(len(list1), len(list2))
list1_combs = list(combinations(list1, num_elements))
list2_perms = list(permutations(list2, num_elements))
result = [
  tuple(zip(perm, comb))
  for comb in list1_combs
  for perm in list2_perms
]

for idx, ((l11, l12), (l21, l22)) in enumerate(result):
  print(f'{idx}: {l11}{l12} {l21}{l22}')

This outputs:

0: A1 B2
1: A1 C2
2: B1 A2
3: B1 C2
4: C1 A2
5: C1 B2

Getting session value in javascript

protected void Page_Load(object sender, EventArgs e)
    {
        Session["MyTest"] = "abcd";

        String csname = "OnSubmitScript";
        Type cstype = this.GetType();

        // Get a ClientScriptManager reference from the Page class.
        ClientScriptManager cs = Page.ClientScript;

        // Check to see if the OnSubmit statement is already registered.
        if (!cs.IsOnSubmitStatementRegistered(cstype, csname))
        {
            string cstext = " document.getElementById(\"TextBox1\").value = getMyvalSession()  ; ";
            cs.RegisterOnSubmitStatement(cstype, csname, cstext);
        }

        if (TextBox1.Text.Equals("")) { }
        else {
              Session["MyTest"] = TextBox1.Text;
        }

    }


<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">

    <script language=javascript type="text/javascript">
        function getMyvalSession() {

             var txt = "efgh";
             var ff = '<%=Session["MyTest"] %>' + txt;
             return ff ;
        }
    </script>

</head>
<body>

    <form id="form1" runat="server">
    <div>
        <asp:TextBox ID="TextBox1" runat="server"  AutoPostBack=true ></asp:TextBox>
     <input type="submit"  value="Submit" />
    </div>
    </form>
</body>
</html>

How do I format a date in Jinja2?

There is a jinja2 extension you can use just need pip install (https://github.com/hackebrot/jinja2-time)

JavaScript - Get Browser Height

I prefer the way I just figured out... No JS... 100% HTML & CSS:

(Will center it perfectly in the middle, regardless of the content size.

HTML FILE

<html><head>
<link href="jane.css" rel="stylesheet" />
</head>
<body>
<table id="container">
<tr>
<td id="centerpiece">
123
</td></tr></table>
</body></html>

CSS FILE

#container{
    border:0;
    width:100%;
    height:100%;
}
#centerpiece{
    vertical-align:middle;
    text-align:center;
}

for centering images / div's held within the td, you may wish to try margin:auto; and specify a div dimension instead. -Though, saying that... the 'text-align' property will align much more than just a simple text element.

Calling a JavaScript function returned from an Ajax response

If your AJAX script takes more than a couple milliseconds to run, eval() will always run ahead and evaluate the empty response element before AJAX populates it with the script you're trying to execute.

Rather than mucking around with timing and eval(), here is a pretty simple workaround that should work in most situations and is probably a bit more secure. Using eval() is generally frowned upon because the characters being evaluated as code can easily be manipulated client-side.

Concept

  1. Include your javascript function in the main page. Write it so that any dynamic elements can be accepted as arguments.
  2. In your AJAX file, call the function by using an official DOM event (onclick, onfocus, onblur, onload, etc.) Depending on what other elements are in your response, you can get pretty clever about making it feel seamless. Pass your dynamic elements in as arguments.
  3. When your response element gets populated and the event takes place, the function runs.

Example

In this example, I want to attach a dynamic autocomplete list from the jquery-ui library to an AJAX element AFTER the element has been added to the page. Easy, right?

start.php

<!DOCTYPE html>
<html>
<head>
<title>Demo</title>
<!-- these libraries are for the autocomplete() function -->
<link rel="stylesheet" type="text/css" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.11.4/themes/ui-lightness/jquery-ui.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.11.4/jquery-ui.min.js"></script>
<script type="text/javascript">
<!--
// this is the ajax call
function editDemoText(ElementID,initialValue) {
    try { ajaxRequest = new XMLHttpRequest();
    } catch (e) {
    try { ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e) {
    try { ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
    } catch (e) {
    return false;
    }}}
    ajaxRequest.onreadystatechange = function() {
        if ( ajaxRequest.readyState == 4 ) {
            var ajaxDisplay = document.getElementById('responseDiv');
            ajaxDisplay.innerHTML = ajaxRequest.responseText;
            }
        }
    var queryString = "?ElementID="+ElementID+"&initialValue="+initialValue;
    ajaxRequest.open("GET", "ajaxRequest.php"+queryString, true);
    ajaxRequest.send(null);
    }

// this is the function we wanted to call in AJAX, 
// but we put it here instead with an argument (ElementID)
function AttachAutocomplete(ElementID) {
    // this list is static, but can easily be pulled in from 
    // a database using PHP. That would look something like this:
    /*
     * $list = "";
     * $r = mysqli_query($mysqli_link, "SELECT element FROM table");
     * while ( $row = mysqli_fetch_array($r) ) {
     *    $list .= "\".str_replace('"','\"',$row['element'])."\",";
     *    }
     * $list = rtrim($list,",");
     */
    var availableIDs = ["Demo1","Demo2","Demo3","Demo4"];
    $("#"+ElementID).autocomplete({ source: availableIDs });
    }
//-->
</script>
</head>
<body>
<!-- this is where the AJAX response sneaks in after DOM is loaded -->
<!-- we're using an onclick event to trigger the initial AJAX call -->
<div id="responseDiv"><a href="javascript:void(0);" onclick="editDemoText('EditableText','I am editable!');">I am editable!</a></div>
</body>
</html>

ajaxRequest.php

<?php
// for this application, onfocus works well because we wouldn't really 
// need the autocomplete populated until the user begins typing
echo "<input type=\"text\" id=\"".$_GET['ElementID']."\" onfocus=\"AttachAutocomplete('".$_GET['ElementID']."');\" value=\"".$_GET['initialValue']."\" />\n";
?>

PHP isset() with multiple parameters

The parameter(s) to isset() must be a variable reference and not an expression (in your case a concatenation); but you can group multiple conditions together like this:

if (isset($_POST['search_term'], $_POST['postcode'])) {
}

This will return true only if all arguments to isset() are set and do not contain null.

Note that isset($var) and isset($var) == true have the same effect, so the latter is somewhat redundant.

Update

The second part of your expression uses empty() like this:

empty ($_POST['search_term'] . $_POST['postcode']) == false

This is wrong for the same reasons as above. In fact, you don't need empty() here, because by that time you would have already checked whether the variables are set, so you can shortcut the complete expression like so:

isset($_POST['search_term'], $_POST['postcode']) && 
    $_POST['search_term'] && 
    $_POST['postcode']

Or using an equivalent expression:

!empty($_POST['search_term']) && !empty($_POST['postcode'])

Final thoughts

You should consider using filter functions to manage the inputs:

$data = filter_input_array(INPUT_POST, array(
    'search_term' => array(
        'filter' => FILTER_UNSAFE_RAW,
        'flags' => FILTER_NULL_ON_FAILURE,
    ),
    'postcode' => array(
        'filter' => FILTER_UNSAFE_RAW,
        'flags' => FILTER_NULL_ON_FAILURE,
    ),
));

if ($data === null || in_array(null, $data, true)) {
    // some fields are missing or their values didn't pass the filter
    die("You did something naughty");
}

// $data['search_term'] and $data['postcode'] contains the fields you want

Btw, you can customize your filters to check for various parts of the submitted values.

Using os.walk() to recursively traverse directories in Python

try this:

#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""FileTreeMaker.py: ..."""

__author__  = "legendmohe"

import os
import argparse
import time

class FileTreeMaker(object):

    def _recurse(self, parent_path, file_list, prefix, output_buf, level):
        if len(file_list) == 0 \
            or (self.max_level != -1 and self.max_level <= level):
            return
        else:
            file_list.sort(key=lambda f: os.path.isfile(os.path.join(parent_path, f)))
            for idx, sub_path in enumerate(file_list):
                if any(exclude_name in sub_path for exclude_name in self.exn):
                    continue

                full_path = os.path.join(parent_path, sub_path)
                idc = "??"
                if idx == len(file_list) - 1:
                    idc = "??"

                if os.path.isdir(full_path) and sub_path not in self.exf:
                    output_buf.append("%s%s[%s]" % (prefix, idc, sub_path))
                    if len(file_list) > 1 and idx != len(file_list) - 1:
                        tmp_prefix = prefix + "?  "
                    else:
                        tmp_prefix = prefix + "    "
                    self._recurse(full_path, os.listdir(full_path), tmp_prefix, output_buf, level + 1)
                elif os.path.isfile(full_path):
                    output_buf.append("%s%s%s" % (prefix, idc, sub_path))

    def make(self, args):
        self.root = args.root
        self.exf = args.exclude_folder
        self.exn = args.exclude_name
        self.max_level = args.max_level

        print("root:%s" % self.root)

        buf = []
        path_parts = self.root.rsplit(os.path.sep, 1)
        buf.append("[%s]" % (path_parts[-1],))
        self._recurse(self.root, os.listdir(self.root), "", buf, 0)

        output_str = "\n".join(buf)
        if len(args.output) != 0:
            with open(args.output, 'w') as of:
                of.write(output_str)
        return output_str

if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument("-r", "--root", help="root of file tree", default=".")
    parser.add_argument("-o", "--output", help="output file name", default="")
    parser.add_argument("-xf", "--exclude_folder", nargs='*', help="exclude folder", default=[])
    parser.add_argument("-xn", "--exclude_name", nargs='*', help="exclude name", default=[])
    parser.add_argument("-m", "--max_level", help="max level",
                        type=int, default=-1)
    args = parser.parse_args()
    print(FileTreeMaker().make(args))

you will get this:

root:.
[.]
??[.idea]
?  ??[scopes]
?  ?  ??scope_settings.xml
?  ??.name
?  ??Demo.iml
?  ??encodings.xml
?  ??misc.xml
?  ??modules.xml
?  ??vcs.xml
?  ??workspace.xml
??[test1]
?  ??test1.txt
??[test2]
?  ??[test2-2]
?  ?  ??[test2-3]
?  ?      ??test2
?  ?      ??test2-3-1
?  ??test2
??folder_tree_maker.py
??tree.py

How to POST URL in data of a curl request

Perhaps you don't have to include the single quotes:

curl --request POST 'http://localhost/Service' --data "path=/xyz/pqr/test/&fileName=1.doc"

Update: Reading curl's manual, you could actually separate both fields with two --data:

curl --request POST 'http://localhost/Service' --data "path=/xyz/pqr/test/" --data "fileName=1.doc"

You could also try --data-binary:

curl --request POST 'http://localhost/Service' --data-binary "path=/xyz/pqr/test/" --data-binary "fileName=1.doc"

And --data-urlencode:

curl --request POST 'http://localhost/Service' --data-urlencode "path=/xyz/pqr/test/" --data-urlencode "fileName=1.doc"

How to make all controls resize accordingly proportionally when window is maximized?

Just thought i'd share this with anyone who needs more clarity on how to achieve this:

myCanvas is a Canvas control and Parent to all other controllers. This code works to neatly resize to any resolution from 1366 x 768 upward. Tested up to 4k resolution 4096 x 2160

Take note of all the MainWindow property settings (WindowStartupLocation, SizeToContent and WindowState) - important for this to work correctly - WindowState for my user case requirement was Maximized

xaml

<Window x:Name="mainWindow" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:MyApp" 
    xmlns:ed="http://schemas.microsoft.com/expression/2010/drawing"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d"
    x:Class="MyApp.MainWindow" 
     Title="MainWindow"  SizeChanged="MainWindow_SizeChanged"
    Width="1366" Height="768" WindowState="Maximized" WindowStartupLocation="CenterOwner" SizeToContent="WidthAndHeight">
  
    <Canvas x:Name="myCanvas" HorizontalAlignment="Left" Height="768" VerticalAlignment="Top" Width="1356">
        <Image x:Name="maxresdefault_1_1__jpg" Source="maxresdefault-1[1].jpg" Stretch="Fill" Opacity="0.6" Height="767" Canvas.Left="-6" Width="1366"/>

        <Separator Margin="0" Background="#FF302D2D" Foreground="#FF111010" Height="0" Canvas.Left="-811" Canvas.Top="148" Width="766"/>
        <Separator Margin="0" Background="#FF302D2D" Foreground="#FF111010" HorizontalAlignment="Right" Width="210" Height="0" Canvas.Left="1653" Canvas.Top="102"/>
        <Image x:Name="imgscroll" Source="BcaKKb47i[1].png" Stretch="Fill" RenderTransformOrigin="0.5,0.5" Height="523" Canvas.Left="-3" Canvas.Top="122" Width="580">
            <Image.RenderTransform>
                <TransformGroup>
                    <ScaleTransform/>
                    <SkewTransform/>
                    <RotateTransform Angle="89.093"/>
                    <TranslateTransform/>
                </TransformGroup>
            </Image.RenderTransform>
        </Image>

.cs

 private void MainWindow_SizeChanged(object sender, SizeChangedEventArgs e)
    {
        myCanvas.Width = e.NewSize.Width;
        myCanvas.Height = e.NewSize.Height;

        double xChange = 1, yChange = 1;

        if (e.PreviousSize.Width != 0)
            xChange = (e.NewSize.Width / e.PreviousSize.Width);

        if (e.PreviousSize.Height != 0)
            yChange = (e.NewSize.Height / e.PreviousSize.Height);

        ScaleTransform scale = new ScaleTransform(myCanvas.LayoutTransform.Value.M11 * xChange, myCanvas.LayoutTransform.Value.M22 * yChange);
        myCanvas.LayoutTransform = scale;
        myCanvas.UpdateLayout();
    }

Using awk to print all columns from the nth to the last

Would this work?

awk '{print substr($0,length($1)+1);}' < file

It leaves some whitespace in front though.

Codeigniter how to create PDF

I have used mpdf in my project. In Codeigniter-3, putted mpdf files under application/third_party and then used in this way:

 /**
 * This function is used to display data in PDF file.
 * function is using mpdf api to generate pdf.
 * @param number $id : This is unique id of table.
 */
function generatePDF($id){
    require APPPATH . '/third_party/mpdf/vendor/autoload.php';
    //$mpdf=new mPDF();
    $mpdf = new mPDF('utf-8', 'Letter', 0, '', 0, 0, 7, 0, 0, 0);

    $checkRecords =  $this->user_model->getCheckInfo($id);      
    foreach ($checkRecords as $key => $value) {
        $data['info'] = $value;
        $filename = $this->load->view(CHEQUE_VIEWS.'index',$data,TRUE);
        $mpdf->WriteHTML($filename); 
    }

    $mpdf->Output(); //output pdf document.
    //$content = $mpdf->Output('', 'S'); //get pdf document content's as variable. 

}

Arithmetic overflow error converting numeric to data type numeric

check your value which you want to store in integer column. I think this is greater then range of integer. if you want to store value greater then integer range. you should use bigint datatype

Apache Spark: map vs mapPartitions?

What's the difference between an RDD's map and mapPartitions method?

The method map converts each element of the source RDD into a single element of the result RDD by applying a function. mapPartitions converts each partition of the source RDD into multiple elements of the result (possibly none).

And does flatMap behave like map or like mapPartitions?

Neither, flatMap works on a single element (as map) and produces multiple elements of the result (as mapPartitions).

How to modify the nodejs request default timeout time?

Linking to express issue #3330

You may set the timeout either globally for entire server:

var server = app.listen();
server.setTimeout(500000);

or just for specific route:

app.post('/xxx', function (req, res) {
   req.setTimeout(500000);
});

jQuery UI DatePicker to show month year only

I needed a Month/Year picker for two fields (From & To) and when one was chosen the Max/Min was set on the other one...a la picking airline ticket dates. I was having issues setting the max and min...the dates of the other field would get erased. Thanks to several of the above posts...I finally figured it out. You have to set options and dates in a very specific order.

See this fiddle for the full solution: Month/Year Picker @ JSFiddle

Code:

var searchMinDate = "-2y";
var searchMaxDate = "-1m";
if ((new Date()).getDate() <= 5) {
    searchMaxDate = "-2m";
}
$("#txtFrom").datepicker({
    dateFormat: "M yy",
    changeMonth: true,
    changeYear: true,
    showButtonPanel: true,
    showAnim: "",
    minDate: searchMinDate,
    maxDate: searchMaxDate,
    showButtonPanel: true,
    beforeShow: function (input, inst) {
        if ((datestr = $("#txtFrom").val()).length > 0) {
            var year = datestr.substring(datestr.length - 4, datestr.length);
            var month = jQuery.inArray(datestr.substring(0, datestr.length - 5), "#txtFrom").datepicker('option', 'monthNamesShort'));
        $("#txtFrom").datepicker('option', 'defaultDate', new Date(year, month, 1));
                $("#txtFrom").datepicker('setDate', new Date(year, month, 1));
            }
        },
        onClose: function (input, inst) {
            var month = $("#ui-datepicker-div .ui-datepicker-month :selected").val();
            var year = $("#ui-datepicker-div .ui-datepicker-year :selected").val();
            $("#txtFrom").datepicker('option', 'defaultDate', new Date(year, month, 1));
            $("#txtFrom").datepicker('setDate', new Date(year, month, 1));
            var to = $("#txtTo").val();
            $("#txtTo").datepicker('option', 'minDate', new Date(year, month, 1));
            if (to.length > 0) {
                var toyear = to.substring(to.length - 4, to.length);
                var tomonth = jQuery.inArray(to.substring(0, to.length - 5), $("#txtTo").datepicker('option', 'monthNamesShort'));
                $("#txtTo").datepicker('option', 'defaultDate', new Date(toyear, tomonth, 1));
                $("#txtTo").datepicker('setDate', new Date(toyear, tomonth, 1));
            }
        }
    });
    $("#txtTo").datepicker({
        dateFormat: "M yy",
        changeMonth: true,
        changeYear: true,
        showButtonPanel: true,
        showAnim: "",
        minDate: searchMinDate,
        maxDate: searchMaxDate,
        showButtonPanel: true,
        beforeShow: function (input, inst) {
            if ((datestr = $("#txtTo").val()).length > 0) {
                var year = datestr.substring(datestr.length - 4, datestr.length);
                var month = jQuery.inArray(datestr.substring(0, datestr.length - 5), $("#txtTo").datepicker('option', 'monthNamesShort'));
                $("#txtTo").datepicker('option', 'defaultDate', new Date(year, month, 1));
                $("#txtTo").datepicker('setDate', new Date(year, month, 1));
            }
        },
        onClose: function (input, inst) {
            var month = $("#ui-datepicker-div .ui-datepicker-month :selected").val();
            var year = $("#ui-datepicker-div .ui-datepicker-year :selected").val();
            $("#txtTo").datepicker('option', 'defaultDate', new Date(year, month, 1));
            $("#txtTo").datepicker('setDate', new Date(year, month, 1));
            var from = $("#txtFrom").val();
            $("#txtFrom").datepicker('option', 'maxDate', new Date(year, month, 1));
            if (from.length > 0) {
                var fryear = from.substring(from.length - 4, from.length);
                var frmonth = jQuery.inArray(from.substring(0, from.length - 5), $("#txtFrom").datepicker('option', 'monthNamesShort'));
                $("#txtFrom").datepicker('option', 'defaultDate', new Date(fryear, frmonth, 1));
                $("#txtFrom").datepicker('setDate', new Date(fryear, frmonth, 1));
            }

        }
    });

Also add this to a style block as mentioned above:

.ui-datepicker-calendar { display: none !important; }

Managing large binary files with Git

I discovered git-annex recently which I find awesome. It was designed for managing large files efficiently. I use it for my photo/music (etc.) collections. The development of git-annex is very active. The content of the files can be removed from the Git repository, only the tree hierarchy is tracked by Git (through symlinks). However, to get the content of the file, a second step is necessary after pulling/pushing, e.g.:

$ git annex add mybigfile
$ git commit -m'add mybigfile'
$ git push myremote
$ git annex copy --to myremote mybigfile ## This command copies the actual content to myremote
$ git annex drop mybigfile ## Remove content from local repo
...
$ git annex get mybigfile ## Retrieve the content
## or to specify the remote from which to get:
$ git annex copy --from myremote mybigfile

There are many commands available, and there is a great documentation on the website. A package is available on Debian.

Programmatically navigate to another view controller/scene

 let vc = DetailUserViewController()
 vc.userdetails = userViewModels[indexPath.row]
 self.navigationController?.pushViewController(vc, animated: true)

Android BroadcastReceiver within Activity

I think your problem is that you send the broadcast before the other activity start ! so the other activity will not receive anything .

  1. The best practice to test your code is to sendbroadcast from thread or from a service so the activity is opened and its registered the receiver and the background process sends a message.
  2. start the ToastDisplay activity from the sender activity ( I didn't test that but it may work probably )

Determine the number of NA values in a column

You're over-thinking the problem:

sum(is.na(df$col))

Write objects into file with Node.js

Just incase anyone else stumbles across this, I use the fs-extra library in node and write javascript objects to a file like this:

const fse = require('fs-extra');
fse.outputJsonSync('path/to/output/file.json', objectToWriteToFile); 

Disable firefox same origin policy

In about:config add content.cors.disable (empty string).

In Oracle SQL: How do you insert the current date + time into a table?

You may try with below query :

INSERT INTO errortable (dateupdated,table1id)
VALUES (to_date(to_char(sysdate,'dd/mon/yyyy hh24:mi:ss'), 'dd/mm/yyyy hh24:mi:ss' ),1083 );

To view the result of it:

SELECT to_char(hire_dateupdated, 'dd/mm/yyyy hh24:mi:ss') 
FROM errortable 
    WHERE table1id = 1083;

Make Frequency Histogram for Factor Variables

If you'd like to do this in ggplot, an API change was made to geom_histogram() that leads to an error: https://github.com/hadley/ggplot2/issues/1465

To get around this, use geom_bar():

animals <- c("cat", "dog",  "dog", "dog", "dog", "dog", "dog", "dog", "cat", "cat", "bird")

library(ggplot2)
# counts
ggplot(data.frame(animals), aes(x=animals)) +
  geom_bar()

enter image description here

How to center a label text in WPF?

Sample:

Label label = new Label();
label.HorizontalContentAlignment = HorizontalAlignment.Center;

How do I list all cron jobs for all users?

you can write for all user list :

sudo crontab -u userName -l

,

You can also go to

cd /etc/cron.daily/
ls -l
cat filename

this file will list the schedules

cd /etc/cron.d/
ls -l
cat filename

How to perform update operations on columns of type JSONB in Postgres 9.4

Matheus de Oliveira created handy functions for JSON CRUD operations in postgresql. They can be imported using the \i directive. Notice the jsonb fork of the functions if jsonb if your data type.

9.3 json https://gist.github.com/matheusoliveira/9488951

9.4 jsonb https://gist.github.com/inindev/2219dff96851928c2282

How to use session in JSP pages to get information?

You can directly use (String)session.getAttribute("username"); inside scriptlet tag ie <% %>.

Twitter Bootstrap - add top space between rows

Bootstrap3

CSS (gutter only, without margins around):

.row.row-gutter {
  margin-bottom: -15px;
  overflow: hidden;
}
.row.row-gutter > *[class^="col"] {
  margin-bottom: 15px;
}

CSS (equal margins around, 15px/2):

.row.row-margins {
  padding-top: 7px; /* or margin-top: 7px; */
  padding-bottom: 7px; /* or margin-bottom: 7px; */
}
.row.row-margins > *[class^="col"] {
  margin-top: 8px;
  margin-bottom: 8px;
}

Usage:

<div class="row row-gutter">
    <div class="col col-sm-9">first</div>
    <div class="col col-sm-3">second</div>
    <div class="col col-sm-12">third</div>
</div>

(with SASS or LESS 15px could be a variable from bootstrap)

How to find numbers from a string?

Based on @brettdj's answer using a VBScript regex ojbect with two modifications:

  • The function handles variants and returns a variant. That is, to take care of a null case; and
  • Uses explicit object creation, with a reference to the "Microsoft VBScript Regular Expressions 5.5" library
Function GetDigitsInVariant(inputVariant As Variant) As Variant
  ' Returns:
  '     Only the digits found in a varaint.
  ' Examples:
  '     GetDigitsInVariant(Null) => Null
  '     GetDigitsInVariant("") => ""
  '     GetDigitsInVariant(2021-/05-May/-18, Tue) => 20210518
  '     GetDigitsInVariant(2021-05-18) => 20210518
  ' Notes:
  '     If the inputVariant is null, null will be returned.
  '     If the inputVariant is "", "" will be returned.
  ' Usage:
  '     VBA IDE Menu > Tools > References ...
  '       > "Microsoft VBScript Regular Expressions 5.5" > [OK]

  ' With an explicit object reference to RegExp we can get intellisense
  ' and review the object heirarchy with the object browser
  ' (VBA IDE Menu > View > Object Browser).
  Dim regex As VBScript_RegExp_55.RegExp
  Set regex = New VBScript_RegExp_55.RegExp
  
  Dim result As Variant
  result = Null
  
  If IsNull(inputVariant) Then
    result = Null
    
  Else
    With regex
      .Global = True
      .Pattern = "[^\d]+"
      result = .Replace(inputVariant, vbNullString)
    End With
  End If
  
  GetDigitsInVariant = result
End Function

Testing:

Private Sub TestGetDigitsInVariant()
  Dim dateVariants As Variant
  dateVariants = Array(Null, "", "2021-/05-May/-18, Tue", _
          "2021-05-18", "18/05/2021", "3434 ..,sdf,sfd 444")
  
  Dim dateVariant As Variant
  For Each dateVariant In dateVariants
    Debug.Print dateVariant & ": ", , GetDigitsInVariant(dateVariant)
  Next dateVariant
  Debug.Print
End Sub

python ValueError: invalid literal for float()

I had a similar issue reading the serial output from a digital scale. I was reading [3:12] out of a 18 characters long output string.

In my case sometimes there is a null character "\x00" (NUL) which magically appears in the scale's reply string and is not printed.

I was getting the error:

> '     0.00'
> 3 0 fast loop, delta =  10.0 weight =  0.0 
> '     0.00'
> 1 800 fast loop, delta = 10.0 weight =  0.0 
> '     0.00'
> 6 0 fast loop, delta =  10.0 weight =  0.0
> '     0\x00.0' 
> Traceback (most recent call last):
>   File "measure_weight_speed.py", line 172, in start
>     valueScale = float(answer_string) 
>     ValueError: invalid literal for float(): 0

After some research I wrote few lines of code that work in my case.

replyScale = scale_port.read(18)
answer = replyScale[3:12]
answer_decode = answer.replace("\x00", "")
answer_strip = str(answer_decode.strip())
print(repr(answer_strip))
valueScale = float(answer_strip)

The answers in these posts helped:

  1. How to get rid of \x00 in my array of bytes?
  2. Invalid literal for float(): 0.000001, how to fix error?

How to run the sftp command with a password from Bash script?

You can use a Python script with scp and os library to make a system call.

  1. ssh-keygen -t rsa -b 2048 (local machine)
  2. ssh-copy-id user@remote_server_address
  3. create a Python script like:
    import os
    cmd = 'scp user@remote_server_address:remote_file_path local_file_path'
    os.system(cmd)
  1. create a rule in crontab to automate your script
  2. done

More than one file was found with OS independent path 'META-INF/LICENSE'

Try to remove multidex from default config and check the build error log. If that log is some relatable with INotification class. Use this in android{}

configurations {
    all*.exclude group: 'com.android.support', module: 'support-v4'
}

This helps me.

Filter values only if not null using lambda in Java8

The proposed answers are great. Just would like to suggest an improvement to handle the case of null list using Optional.ofNullable, new feature in Java 8:

 List<String> carsFiltered = Optional.ofNullable(cars)
                .orElseGet(Collections::emptyList)
                .stream()
                .filter(Objects::nonNull)
                .collect(Collectors.toList());

So, the full answer will be:

 List<String> carsFiltered = Optional.ofNullable(cars)
                .orElseGet(Collections::emptyList)
                .stream()
                .filter(Objects::nonNull) //filtering car object that are null
                .map(Car::getName) //now it's a stream of Strings
                .filter(Objects::nonNull) //filtering null in Strings
                .filter(name -> name.startsWith("M"))
                .collect(Collectors.toList()); //back to List of Strings

Is it possible to insert multiple rows at a time in an SQLite database?

If you are using bash shell you can use this:

time bash -c $'
FILE=/dev/shm/test.db
sqlite3 $FILE "create table if not exists tab(id int);"
sqlite3 $FILE "insert into tab values (1),(2)"
for i in 1 2 3 4; do sqlite3 $FILE "INSERT INTO tab (id) select (a.id+b.id+c.id)*abs(random()%1e7) from tab a, tab b, tab c limit 5e5"; done; 
sqlite3 $FILE "select count(*) from tab;"'

Or if you are in sqlite CLI, then you need to do this:

create table if not exists tab(id int);"
insert into tab values (1),(2);
INSERT INTO tab (id) select (a.id+b.id+c.id)*abs(random()%1e7) from tab a, tab b, tab c limit 5e5;
INSERT INTO tab (id) select (a.id+b.id+c.id)*abs(random()%1e7) from tab a, tab b, tab c limit 5e5;
INSERT INTO tab (id) select (a.id+b.id+c.id)*abs(random()%1e7) from tab a, tab b, tab c limit 5e5;
INSERT INTO tab (id) select (a.id+b.id+c.id)*abs(random()%1e7) from tab a, tab b, tab c limit 5e5;
select count(*) from tab;

How does it work? It makes use of that if table tab:

id int
------
1
2

then select a.id, b.id from tab a, tab b returns

a.id int | b.id int
------------------
    1    | 1
    2    | 1
    1    | 2
    2    | 2

and so on. After first execution we insert 2 rows, then 2^3=8. (three because we have tab a, tab b, tab c)

After second execution we insert additional (2+8)^3=1000 rows

Aftern thrid we insert about max(1000^3, 5e5)=500000 rows and so on...

This is the fastest known for me method of populating SQLite database.

Trim leading and trailing spaces from a string in awk

If you want to trim all spaces, only in lines that have a comma, and use awk, then the following will work for you:

awk -F, '/,/{gsub(/ /, "", $0); print} ' input.txt

If you only want to remove spaces in the second column, change the expression to

awk -F, '/,/{gsub(/ /, "", $2); print$1","$2} ' input.txt

Note that gsub substitutes the character in // with the second expression, in the variable that is the third parameter - and does so in-place - in other words, when it's done, the $0 (or $2) has been modified.

Full explanation:

-F,            use comma as field separator 
               (so the thing before the first comma is $1, etc)
/,/            operate only on lines with a comma 
               (this means empty lines are skipped)
gsub(a,b,c)    match the regular expression a, replace it with b, 
               and do all this with the contents of c
print$1","$2   print the contents of field 1, a comma, then field 2
input.txt      use input.txt as the source of lines to process

EDIT I want to point out that @BMW's solution is better, as it actually trims only leading and trailing spaces with two successive gsub commands. Whilst giving credit I will give an explanation of how it works.

gsub(/^[ \t]+/,"",$2);    - starting at the beginning (^) replace all (+ = zero or more, greedy)
                             consecutive tabs and spaces with an empty string
gsub(/[ \t]+$/,"",$2)}    - do the same, but now for all space up to the end of string ($)
1                         - ="true". Shorthand for "use default action", which is print $0
                          - that is, print the entire (modified) line

How do I see what character set a MySQL database / table / column is?

For database : USE db_name; SELECT @@character_set_database;

whitespaces in the path of windows filepath

There is no problem with whitespaces in the path since you're not using the "shell" to open the file. Here is a session from the windows console to prove the point. You're doing something else wrong

Python 2.7.2 (default, Jun 12 2011, 14:24:46) [MSC v.1500 64 bit (AMD64)] on wi
32
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>>
>>> os.makedirs("C:/ABC/SEM 2/testfiles")
>>> open("C:/ABC/SEM 2/testfiles/all.txt","w")
<open file 'C:/ABC/SEM 2/testfiles/all.txt', mode 'w' at 0x0000000001D95420>
>>> exit()

C:\Users\Gnibbler>dir "C:\ABC\SEM 2\testfiles"
 Volume in drive C has no label.
 Volume Serial Number is 46A0-BB64

 Directory of c:\ABC\SEM 2\testfiles

13/02/2013  10:20 PM    <DIR>          .
13/02/2013  10:20 PM    <DIR>          ..
13/02/2013  10:20 PM                 0 all.txt
               1 File(s)              0 bytes
               2 Dir(s)  78,929,309,696 bytes free

C:\Users\Gnibbler>

How to Replace Multiple Characters in SQL?

declare @testVal varchar(20)

set @testVal = '?t/es?ti/n*g 1*2?3*'

select @testVal = REPLACE(@testVal, item, '') from (select '?' item union select '*' union select '/') list

select @testVal;

How to sort a Collection<T>?

Assuming you have a list of object of type Person, using Lambda expression, you can sort the last names of users for instance by doing the following:

import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

class Person {
        private String firstName;
        private String lastName;

        public Person(String firstName, String lastName){
            this.firstName = firstName;
            this.lastName = lastName;
        }

        public String getLastName(){
            return this.lastName;
        }

        public String getFirstName(){
            return this.firstName;
        }

        @Override
        public String toString(){
            return "Person: "+ this.getFirstName() + " " + this.getLastName();
        }
    }

    class TestSort {
        public static void main(String[] args){
            List<Person> people = Arrays.asList(
                                  new Person("John", "Max"), 
                                  new Person("Coolio", "Doe"), 
                                  new Person("Judith", "Dan")
            );

            //Making use of lambda expression to sort the collection
            people.sort((p1, p2)->p1.getLastName().compareTo(p2.getLastName()));

            //Print sorted 
            printPeople(people);
        }

        public static void printPeople(List<Person> people){
            for(Person p : people){
                System.out.println(p);
            }
        }
    }

How to get a random number between a float range?

random.uniform(a, b) appears to be what your looking for. From the docs:

Return a random floating point number N such that a <= N <= b for a <= b and b <= N <= a for b < a.

See here.

Remove category & tag base from WordPress url - without a plugin

The non-category plugin did not work for me.

For Multisite WordPress the following works:

  1. Go to network admin sites;
  2. Open site under \;
  3. Go to settings;
  4. Under permalinks structure type /%category%/%postname%/. This will display your url as www.domainname.com/categoryname/postname;
  5. Now go to your site dashboard (not network dashboard);
  6. Open settings;
  7. Open permalink. Do not save (the permalink will show uneditable field as yourdoamainname/blog/. Ignore it. If you save now the work you did in step 4 will be overwritten. This step of opening permalink page but not saving in needed to update the database.

How can I programmatically determine if my app is running in the iphone simulator?

Updated code:

This is purported to work officially.

#if TARGET_IPHONE_SIMULATOR
NSString *hello = @"Hello, iPhone simulator!";
#elif TARGET_OS_IPHONE
NSString *hello = @"Hello, device!";
#else
NSString *hello = @"Hello, unknown target!";
#endif

Original post (since deprecated)

This code will tell you if you are running in a simulator.

#ifdef __i386__
NSLog(@"Running in the simulator");
#else
NSLog(@"Running on a device");
#endif

What range of values can integer types store in C++

The size of the numerical types is not defined in the C++ standard, although the minimum sizes are. The way to tell what size they are on your platform is to use numeric limits

For example, the maximum value for a int can be found by:

std::numeric_limits<int>::max();

Computers don't work in base 10, which means that the maximum value will be in the form of 2n-1 because of how the numbers of represent in memory. Take for example eight bits (1 byte)

  0100 1000

The right most bit (number) when set to 1 represents 20, the next bit 21, then 22 and so on until we get to the left most bit which if the number is unsigned represents 27.

So the number represents 26 + 23 = 64 + 8 = 72, because the 4th bit from the right and the 7th bit right the left are set.

If we set all values to 1:

11111111

The number is now (assuming unsigned)
128 + 64 + 32 + 16 + 8 + 4 + 2 + 1 = 255 = 28 - 1
And as we can see, that is the largest possible value that can be represented with 8 bits.

On my machine and int and a long are the same, each able to hold between -231 to 231 - 1. In my experience the most common size on modern 32 bit desktop machine.

Delete all the queues from RabbitMQ?

In case you only want to purge the queues which are not empty (a lot faster):

rabbitmqctl list_queues | awk '$2!=0 { print $1 }' | sed 's/Listing//' | xargs -L1 rabbitmqctl purge_queue

For me, it takes 2-3 seconds to purge a queue (both empty and non-empty ones), so iterating through 50 queues is such a pain while I just need to purge 10 of them (40/50 are empty).

How can I remove the last character of a string in python?

You could use String.rstrip.

result = string.rstrip('/')

How to find the privileges and roles granted to a user in Oracle?

In addition to VAV's answer, The first one was most useful in my environment

select * from USER_ROLE_PRIVS where USERNAME='SAMPLE';
select * from USER_TAB_PRIVS where Grantee = 'SAMPLE';
select * from USER_SYS_PRIVS where USERNAME = 'SAMPLE';

PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL

For tables you must loop that:

for tbl in `psql -qAt -c "select tablename from pg_tables where schemaname = 'public';" YOUR_DB` ; do  psql -U postgres -c "alter table \"$tbl\" owner to NEW_USER" YOUR_DB ; done

How can I run PowerShell with the .NET 4 runtime?

Actually, you can get PowerShell to run using .NET 4 without affecting other .NET applications. I needed to do so to use the new HttpWebRequest "Host" property, however changing the "OnlyUseLatestCLR" broke Fiddler as that could not be used under .NET 4.

The developers of PowerShell obviously foresaw this happening, and they added a registry key to specify what version of the Framework it should use. One slight issue is that you need to take ownership of the registry key before changing it, as even administrators do not have access.

  • HKLM:\Software\Microsoft\Powershell\1\PowerShellEngine\RuntimeVersion (64 bit and 32 bit)
  • HKLM:\Software\Wow6432Node\Microsoft\Powershell\1\PowerShellEngine\RuntimeVersion (32 bit on 64 bit machine)

Change the value of that key to the required version. Keep in mind though that some snapins may no longer load unless they are .NET 4 compatible (WASP is the only one I have had trouble with, but I don't really use it anyway). VMWare, SQL Server 2008, PSCX, Active Directory (Microsoft and Quest Software) and SCOM all work fine.

What is EOF in the C programming language?

nput from a terminal never really "ends" (unless the device is disconnected), but it is useful to enter more than one "file" into a terminal, so a key sequence is reserved to indicate end of input. In UNIX the translation of the keystroke to EOF is performed by the terminal driver, so a program does not need to distinguish terminals from other input files. By default, the driver converts a Control-D character at the start of a line into an end-of-file indicator. To insert an actual Control-D (ASCII 04) character into the input stream, the user precedes it with a "quote" command character (usually Control-V). AmigaDOS is similar but uses Control-\ instead of Control-D.

In Microsoft's DOS and Windows (and in CP/M and many DEC operating systems), reading from the terminal will never produce an EOF. Instead, programs recognize that the source is a terminal (or other "character device") and interpret a given reserved character or sequence as an end-of-file indicator; most commonly this is an ASCII Control-Z, code 26. Some MS-DOS programs, including parts of the Microsoft MS-DOS shell (COMMAND.COM) and operating-system utility programs (such as EDLIN), treat a Control-Z in a text file as marking the end of meaningful data, and/or append a Control-Z to the end when writing a text file. This was done for two reasons:

  1. Backward compatibility with CP/M. The CP/M file system only recorded the lengths of files in multiples of 128-byte "records", so by convention a Control-Z character was used to mark the end of meaningful data if it ended in the middle of a record. The MS-DOS filesystem has always recorded the exact byte-length of files, so this was never necessary on MS-DOS.

  2. It allows programs to use the same code to read input from both a terminal and a text file.

How to add property to object in PHP >= 5.3 strict mode without generating error

Do it like this:

$foo = new stdClass();
$foo->{"bar"} = '1234';

now try:

echo $foo->bar; // should display 1234

Add 2 hours to current time in MySQL?

The DATE_ADD() function will do the trick. (You can also use the ADDTIME() function if you're running at least v4.1.1.)

For your query, this would be:

SELECT * 
FROM courses 
WHERE DATE_ADD(now(), INTERVAL 2 HOUR) > start_time

Or,

SELECT * 
FROM courses 
WHERE ADDTIME(now(), '02:00:00') > start_time

Select all contents of textbox when it receives focus (Vanilla JS or jQuery)

$(document).ready(function() {
    $("input:text").focus(function() { $(this).select(); } );
});

Is there possibility of sum of ArrayList without looping

The only alternative to using a loop is to use recursion.

You can define a method like

public static int sum(List<Integer> ints) {
   return ints.isEmpty() ? 0 : ints.get(0) + ints.subList(1, ints.length());
}

This is very inefficient compared to using a plain loop and can blow up if you have many elements in the list.

An alternative which avoid a stack overflow is to use.

public static int sum(List<Integer> ints) {
    int len = ints.size();
    if (len == 0) return 0;
    if (len == 1) return ints.get(0);
    return sum(ints.subList(0, len/2)) + sum(ints.subList(len/2, len));
}

This is just as inefficient, but will avoid a stack overflow.


The shortest way to write the same thing is

int sum = 0, a[] = {2, 4, 6, 8};

for(int i: a) {
    sum += i;
}

System.out.println("sum(a) = " + sum);

prints

sum(a) = 20

'Access denied for user 'root'@'localhost' (using password: NO)'

For some information I've get error after changing password:

Access denied for user 'root'@'localhost' (using password: NO)

Access denied for user 'root'@'localhost' (using password: YES)

In both cases there was error.

But the thing is after that I've tried it with

mysql -uroot -ppassword instead of

mysql -u root -p password -> with spaces between -uroot and -ppassword so maybe if someone get trouble can try this way.

How add spaces between Slick carousel item

Try to use pseudo classes like :first-child & :last-child to remove extra padding from first & last child.

Inspect the generated code of slick slider & try to remove padding on that.

Hope, it'll help!!!

How does the "final" keyword in Java work? (I can still modify an object.)

Worth to mention some straightforward definitions:

Classes/Methods

You can declare some or all of a class methods as final, in order to indicate that the method cannot be overridden by subclasses.

Variables

Once a final variable has been initialized, it always contains the same value.

final basically avoid overwrite/superscribe by anything (subclasses, variable "reassign"), depending on the case.

sorting integers in order lowest to highest java

Take Inputs from User and Insertion Sort. Here is how it works:

package com.learning.constructor;

import java.util.Scanner;



public class InsertionSortArray {

public static void main(String[] args) {    

Scanner s=new Scanner(System.in);

System.out.println("enter number of elements");

int n=s.nextInt();


int arr[]=new int[n];

System.out.println("enter elements");

for(int i=0;i<n;i++){//for reading array
    arr[i]=s.nextInt();

}

System.out.print("Your Array Is: ");
//for(int i: arr){ //for printing array
for (int i = 0; i < arr.length; i++){
    System.out.print(arr[i] + ",");

}
System.out.println("\n");        

    int[] input = arr;
    insertionSort(input);
}

private static void printNumbers(int[] input) {

    for (int i = 0; i < input.length; i++) {
        System.out.print(input[i] + ", ");
    }
    System.out.println("\n");
}

public static void insertionSort(int array[]) {
    int n = array.length;
    for (int j = 1; j < n; j++) {
        int key = array[j];
        int i = j-1;
        while ( (i > -1) && ( array [i] > key ) ) {
            array [i+1] = array [i];
            i--;
        }
        array[i+1] = key;
        printNumbers(array);
    }
}

}

How to replace multiple strings in a file using PowerShell

A third option, for a pipelined one-liner is to nest the -replaces:

PS> ("ABC" -replace "B","C") -replace "C","D"
ADD

And:

PS> ("ABC" -replace "C","D") -replace "B","C"
ACD

This preserves execution order, is easy to read, and fits neatly into a pipeline. I prefer to use parentheses for explicit control, self-documentation, etc. It works without them, but how far do you trust that?

-Replace is a Comparison Operator, which accepts an object and returns a presumably modified object. This is why you can stack or nest them as shown above.

Please see:

help about_operators

Select query to remove non-numeric characters

You can create SQL CLR scalar function in order to be able to use regular expressions like replace patterns.

Here you can find example of how to create such function.

Having such function will solve the issue with just the following lines:

SELECT [dbo].[fn_Utils_RegexReplace] ('AB ABCDE # 123', '[^0-9]', '');
SELECT [dbo].[fn_Utils_RegexReplace] ('ABCDE# 123', '[^0-9]', '');
SELECT [dbo].[fn_Utils_RegexReplace] ('AB: ABC# 123', '[^0-9]', '');

More important, you will be able to solve more complex issues as the regular expressions will bring a whole new world of options directly in your T-SQL statements.

Linux delete file with size 0

find . -type f -empty -exec rm -f {} \;

What is the difference between a mutable and immutable string in C#?

Mutable and immutable are English words meaning "can change" and "cannot change" respectively. The meaning of the words is the same in the IT context; i.e.

  • a mutable string can be changed, and
  • an immutable string cannot be changed.

The meanings of these words are the same in C# / .NET as in other programming languages / environments, though (obviously) the names of the types may differ, as may other details.


For the record:

  • String is the standard C# / .Net immutable string type
  • StringBuilder is the standard C# / .Net mutable string type

To "effect a change" on a string represented as a C# String, you actually create a new String object. The original String is not changed ... because it is unchangeable.

In most cases it is better to use String because it is easier reason about them; e.g. you don't need to consider the possibility that some other thread might "change my string".

However, when you need to construct or modify a string using a sequence of operations, it may be more efficient to use a StringBuilder. An example is when you are concatenating many string fragments to form a large string:

  • If you do this as a sequence of String concatenations, you copy O(N^2) characters, where N is the number of component strings.
  • If use a StringBuilder you only copy O(N) characters.

And finally, for those people who assert that a StringBuilder is not a string because it is not immutable, the Microsoft documentation describes StringBuilder thus:

"Represents a mutable string of characters. This class cannot be inherited."

Web link to specific whatsapp contact

The following link seems to work fine -

<a href="whatsapp://send?text=Hello World!&phone=+9198********1">Ping me on WhatsApp</a>

It opens the contact in WhatsApp app, along with the message 'Hello World!' prepopulated in the input text box.

(Tested this with google chrome on an android phone.)

How do I extract text that lies between parentheses (round brackets)?

Regular expressions might be the best tool here. If you are not famililar with them, I recommend you install Expresso - a great little regex tool.

Something like:

Regex regex = new Regex("\\((?<TextInsideBrackets>\\w+)\\)");
string incomingValue = "Username (sales)";
string insideBrackets = null;
Match match = regex.Match(incomingValue);
if(match.Success)
{
    insideBrackets = match.Groups["TextInsideBrackets"].Value;
}

Simplest way to do grouped barplot

There are several ways to do plots in R; lattice is one of them, and always a reasonable solution, +1 to @agstudy. If you want to do this in base graphics, you could try the following:

Reasonstats <- read.table(text="Category         Reason  Species
                                 Decline        Genuine       24
                                Improved        Genuine       16
                                Improved  Misclassified       85
                                 Decline  Misclassified       41
                                 Decline      Taxonomic        2
                                Improved      Taxonomic        7
                                 Decline        Unclear       41
                                Improved        Unclear      117", header=T)

ReasonstatsDec <- Reasonstats[which(Reasonstats$Category=="Decline"),]
ReasonstatsImp <- Reasonstats[which(Reasonstats$Category=="Improved"),]
Reasonstats3   <- cbind(ReasonstatsImp[,3], ReasonstatsDec[,3])
colnames(Reasonstats3) <- c("Improved", "Decline")
rownames(Reasonstats3) <- ReasonstatsImp$Reason

windows()
  barplot(t(Reasonstats3), beside=TRUE, ylab="number of species", 
          cex.names=0.8, las=2, ylim=c(0,120), col=c("darkblue","red"))
  box(bty="l")

enter image description here

Here's what I did: I created a matrix with two columns (because your data were in columns) where the columns were the species counts for Decline and for Improved. Then I made those categories the column names. I also made the Reasons the row names. The barplot() function can operate over this matrix, but wants the data in rows rather than columns, so I fed it a transposed version of the matrix. Lastly, I deleted some of your arguments to your barplot() function call that were no longer needed. In other words, the problem was that your data weren't set up the way barplot() wants for your intended output.

How can I switch my signed in user in Visual Studio 2013?

I resolved this problem by deleting the registry key under

hkey_current_user\software\Microsoft\VSCommon\12.0\clientservices\tokenstorage\visualstudio\ideuser

Input type for HTML form for integer

Even if you want to accept numbers for the input, I would recommend using the text type.

<input type="text" name"some-number" />

Client-side run some jQuery validations to verify it's a number.

Then in your server side code, run some validation to verify it is in fact a numerical value.

Test if numpy array contains only zeros

This will work.

def check(arr):
    if np.all(arr == 0):
        return True
    return False