Programs & Examples On #Multi agent

A Multi-Agent System (MAS) is a system composed of multiple interacting intelligent agents within a given environment based on the new paradigm for conceptualizing, designing, and implementing software systems.

How to remove all non-alpha numeric characters from a string in MySQL?

if you are using php then....

try{
$con = new PDO ("mysql:host=localhost;dbname=dbasename","root","");
}
catch(PDOException $e){
echo "error".$e-getMessage();   
}

$select = $con->prepare("SELECT * FROM table");
$select->setFetchMode(PDO::FETCH_ASSOC);
$select->execute();

while($data=$select->fetch()){ 

$id = $data['id'];
$column = $data['column'];
$column = preg_replace("/[^a-zA-Z0-9]+/", " ", $column); //remove all special characters

$update = $con->prepare("UPDATE table SET column=:column WHERE id='$id'");
$update->bindParam(':column', $column );
$update->execute();

// echo $column."<br>";
} 

Convert HTML to NSAttributedString in iOS

Here is the Swift 5 version of Mobile Dan's answer:

public extension NSAttributedString {
    convenience init?(_ html: String) {
        guard let data = html.data(using: .unicode) else {
                return nil
        }

        try? self.init(data: data, options: [.documentType: NSAttributedString.DocumentType.html], documentAttributes: nil)
    }
}

How do I get this javascript to run every second?

Use setInterval() to run a piece of code every x milliseconds.

You can wrap the code you want to run every second in a function called runFunction.

So it would be:

var t=setInterval(runFunction,1000);

And to stop it, you can run:

clearInterval(t);

Routing with multiple Get methods in ASP.NET Web API

  // this piece of code in the WebApiConfig.cs file or your custom bootstrap application class
  // define two types of routes 1. DefaultActionApi  and 2. DefaultApi as below

   config.Routes.MapHttpRoute("DefaultActionApi", "api/{controller}/{action}/{id}", new { id = RouteParameter.Optional });
   config.Routes.MapHttpRoute("DefaultApi", "api/{controller}/{id}", new { action = "Default", id = RouteParameter.Optional });

  // decorate the controller action method with [ActionName("Default")] which need to invoked with below url
  // http://localhost:XXXXX/api/Demo/ -- will invoke the Get method of Demo controller
  // http://localhost:XXXXX/api/Demo/GetAll -- will invoke the GetAll method of Demo controller
  // http://localhost:XXXXX/api/Demo/GetById -- will invoke the GetById method of Demo controller
  // http://localhost:57870/api/Demo/CustomGetDetails -- will invoke the CustomGetDetails method of Demo controller
  // http://localhost:57870/api/Demo/DemoGet -- will invoke the DemoGet method of Demo controller


 public class DemoController : ApiController
 {
    // Mark the method with ActionName  attribute (defined in MapRoutes) 
    [ActionName("Default")]
    public HttpResponseMessage Get()
    {
        return Request.CreateResponse(HttpStatusCode.OK, "Get Method");
    }

    public HttpResponseMessage GetAll()
    {
        return Request.CreateResponse(HttpStatusCode.OK, "GetAll Method");
    }

    public HttpResponseMessage GetById()
    {
        return Request.CreateResponse(HttpStatusCode.OK, "Getby Id Method");
    }

    //Custom Method name
    [HttpGet]
    public HttpResponseMessage DemoGet()
    {
        return Request.CreateResponse(HttpStatusCode.OK, "DemoGet Method");
    }

    //Custom Method name
    [HttpGet]
    public HttpResponseMessage CustomGetDetails()
    {
        return Request.CreateResponse(HttpStatusCode.OK, "CustomGetDetails Method");
    }
}

OSX El Capitan: sudo pip install OSError: [Errno: 1] Operation not permitted

I had the same problems, but using easy_install "module" solved the problem for me.

I am not sure why, but pip and easy_install use different install locations, and easy_install chose the right ones.

Edit: without re-checking but because of the comments; it seems that different (OSX and brew-installed) installations interfere with each other which is why they tools mentioned indeed point to different locations (since they belong to different installations). I understand that usually those tools from one install point to the same folder.

Android Completely transparent Status Bar?

Here is a extension in kotlin that do the trick:

fun Activity.setTransparentStatusBar() {
    window.decorView.systemUiVisibility = View.SYSTEM_UI_FLAG_LAYOUT_STABLE or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
        window.statusBarColor = Color.TRANSPARENT
    }
}

Python convert set to string and vice versa

Use repr and eval:

>>> s = set([1,2,3])
>>> strs = repr(s)
>>> strs
'set([1, 2, 3])'
>>> eval(strs)
set([1, 2, 3])

Note that eval is not safe if the source of string is unknown, prefer ast.literal_eval for safer conversion:

>>> from ast import literal_eval
>>> s = set([10, 20, 30])
>>> lis = str(list(s))
>>> set(literal_eval(lis))
set([10, 20, 30])

help on repr:

repr(object) -> string
Return the canonical string representation of the object.
For most object types, eval(repr(object)) == object.

How do you make Git work with IntelliJ?

git.exe is common for any git based applications like GitHub, Bitbucket etc. Some times it is possible that you have already installed another git based application so git.exe will be present in the bin folder of that application.

For example if you installed bitbucket before github in your PC, you will find git.exe in C:\Users\{username}\AppData\Local\Atlassian\SourceTree\git_local\bin instead of C:\Users\{username}\AppData\Local\GitHub\PortableGit.....\bin.

How to avoid the "divide by zero" error in SQL?

  1. Add a CHECK constraint that forces Divisor to be non-zero
  2. Add a validator to the form so that the user cannot enter zero values into this field.

How can I get a process handle by its name in C++?

Check out: MSDN Article

You can use GetModuleName (I think?) to get the name and check against that.

How to clear all input fields in a specific div with jQuery?

Change this:

 <div class=fetch_results>

To this:

 <div id="fetch_results">

Then the following should work:

$("#fetch_results input").each(function() {
      this.value = "";
  })?

http://jsfiddle.net/NVqeR/

How can I remove a character from a string using JavaScript?

Just fix your replaceAt:

String.prototype.replaceAt = function(index, charcount) {
  return this.substr(0, index) + this.substr(index + charcount);
}

mystring.replaceAt(4, 1);

I'd call it removeAt instead. :)

Find in Files: Search all code in Team Foundation Server

If you install TFS 2008 PowerTools you will get a "Find in Source Control" action in the Team Explorer right click menu.

TFS2008 Power Tools

Is it a good idea to index datetime field in mysql?

MySQL recommends using indexes for a variety of reasons including elimination of rows between conditions: http://dev.mysql.com/doc/refman/5.0/en/mysql-indexes.html

This makes your datetime column an excellent candidate for an index if you are going to be using it in conditions frequently in queries. If your only condition is BETWEEN NOW() AND DATE_ADD(NOW(), INTERVAL 30 DAY) and you have no other index in the condition, MySQL will have to do a full table scan on every query. I'm not sure how many rows are generated in 30 days, but as long as it's less than about 1/3 of the total rows it will be more efficient to use an index on the column.

Your question about creating an efficient database is very broad. I'd say to just make sure that it's normalized and all appropriate columns are indexed (i.e. ones used in joins and where clauses).

Servlet for serving static content

I ended up rolling my own StaticServlet. It supports If-Modified-Since, gzip encoding and it should be able to serve static files from war-files as well. It is not very difficult code, but it is not entirely trivial either.

The code is available: StaticServlet.java. Feel free to comment.

Update: Khurram asks about the ServletUtils class which is referenced in StaticServlet. It is simply a class with auxiliary methods that I used for my project. The only method you need is coalesce (which is identical to the SQL function COALESCE). This is the code:

public static <T> T coalesce(T...ts) {
    for(T t: ts)
        if(t != null)
            return t;
    return null;
}

Disable Chrome strict MIME type checking

For Windows Users :

If this issue occurs on your self hosted server (eg: your custom CDN) and the browser (Chrome) says something like ... ('text/plain') is not executable ... when trying to load your javascript file ...

Here is what you need to do :

  1. Open the Registry Editor i.e Win + R > regedit
  2. Head over to HKEY_LOCAL_MACHINE\SOFTWARE\Classes\.js
  3. Check to if the Content Type is application/javascript or not
  4. If not, then change it to application/javascript and try again

how to create and call scalar function in sql server 2008

Or you can simply use PRINT command instead of SELECT command. Try this,

PRINT dbo.fn_HomePageSlider(9, 3025)

Publish to IIS, setting Environment Variable

I know a lot of answers has been given but in my case I added web.{Environment}.config versions in my project and when publishing for a particular environment the value gets replaced.


For example, for Staging (web.Staging.config)

<?xml version="1.0"?>
<configuration xmlns:xdt="http://schemas.microsoft.com/XML-Document-Transform">
    <location>
        <system.webServer>
            <aspNetCore>
                <environmentVariables xdt:Transform="InsertIfMissing">
                    <environmentVariable name="ASPNETCORE_ENVIRONMENT"
                                         value="Staging"
                                         xdt:Locator="Match(name)"
                                         xdt:Transform="InsertIfMissing" />
                </environmentVariables>
            </aspNetCore>
        </system.webServer>
    </location>
</configuration>

For Release or Production I will do this (web.Release.config)

<?xml version="1.0"?>
<configuration xmlns:xdt="http://schemas.microsoft.com/XML-Document-Transform">
    <location>
        <system.webServer>
            <aspNetCore>
                <environmentVariables xdt:Transform="InsertIfMissing">
                    <environmentVariable name="ASPNETCORE_ENVIRONMENT"
                                         value="Release"
                                         xdt:Locator="Match(name)"
                                         xdt:Transform="InsertIfMissing" />
                </environmentVariables>
            </aspNetCore>
        </system.webServer>
    </location>
</configuration>

Then when publishing I will choose or set the environment name. And this will replace the value of the environment in the eventual web.config file.

jQuery or Javascript - how to disable window scroll without overflow:hidden;

You can use jquery-disablescroll to solve the problem:

  • Disable scrolling: $window.disablescroll();
  • Enable scrolling again: $window.disablescroll("undo");

Supports handleWheel, handleScrollbar, handleKeys and scrollEventKeys.

Clear all fields in a form upon going back with browser back button

Another way without JavaScript is to use <form autocomplete="off"> to prevent the browser from re-filling the form with the last values.

See also this question

Tested this only with a single <input type="text"> inside the form, but works fine in current Chrome and Firefox, unfortunately not in IE10.

JAVA_HOME is set to an invalid directory:

Please remove /bin and even semi colon ; from JAVA_HOME to resolve.

Class 'App\Http\Controllers\DB' not found and I also cannot use a new Model

There is problem in name spacing as in laravel 5.2.3

use DB;
use App\ApiModel; OR  use App\name of model; 

DB::table('tbl_users')->insert($users); 

OR

DB::table('table name')->insert($users);



model 

class ApiModel extends Model
    {

        protected $table='tbl_users';

}

How to disable scrolling temporarily?

This is the simplest solution I got so far. And believe me I tried all the others and this is the easiest one. It works great on Windows devices, which pushes the page from the right to have room for the system scrollbar and IOS devices which don't require space for their scrollbars in the browsers. So by using this you wont need to add padding on the right so the page doesn't flicker when you hide the overflow of the body or html with css.

The solution is pretty simple if you think about it. The idea is to give the window.scrollTop() the same exact position at the moment that a popup is opened. Also change that position when the window resizes ( as the scroll position changes once that happens ).

So here we go...

First lets create the variable that will let you know that the popup is open and call it stopWindowScroll. If we don't do this then you'll get an error of an undefined variable on your page and set it to 0 - as not active.

$(document).ready(function(){
    stopWindowScroll = 0;
});

Now lets make the open popup function witch can be any function in your code that triggers whatever popup you are using as a plugin or custom. In this case it will be a simple custom popup with a simple document on click function.

$(document).on('click','.open-popup', function(){
    // Saving the scroll position once opening the popup.
    stopWindowScrollPosition = $(window).scrollTop();
    // Setting the stopWindowScroll to 1 to know the popup is open.
    stopWindowScroll = 1;
    // Displaying your popup.
    $('.your-popup').fadeIn(300);
});

So the next thing we do is create the close popup function, which I repeat again can be any function you already have created or are using in a plugin. The important thing is that we need those 2 functions to set the stopWindowScroll variable to 1 or 0 to know when it's open or closed.

$(document).on('click','.open-popup', function(){
    // Setting the stopWindowScroll to 0 to know the popup is closed.
    stopWindowScroll = 0;
    // Hiding your popup
    $('.your-popup').fadeOut(300);
});

Then lets create the window.scroll function so we can prevent the scrolling once the stopWindowScroll mentioned above is set to 1 - as active.

$(window).scroll(function(){
    if(stopWindowScroll == 1) {
         // Giving the window scrollTop() function the position on which
         // the popup was opened, this way it will stay in its place.
         $(window).scrollTop(stopWindowScrollPosition);
    }
});

Thats it. No CSS required for this to work except your own styles for the page. This worked like a charm for me and I hope it helps you and others.

Here is a working example on JSFiddle:

JS Fiddle Example

Let me know if this helped. Regards.

Can a PDF file's print dialog be opened with Javascript?

I usually do something similar to the approach given by How to Use JavaScript to Print a PDF (eHow.com), using an iframe.

  1. a function to house the print trigger...

    function printTrigger(elementId) {
        var getMyFrame = document.getElementById(elementId);
        getMyFrame.focus();
        getMyFrame.contentWindow.print();
    }
    
  2. an button to give the user access...

    (an onClick on an a or button or input or whatever you wish)

    <input type="button" value="Print" onclick="printTrigger('iFramePdf');" />
    
  3. an iframe pointing to your PDF...

    <iframe id="iFramePdf" src="myPdfUrl.pdf" style="display:none;"></iframe>
    

Bonus Idea #1 - Create the iframe and add it to your page within the printTrigger(); so that the PDF isn't loaded until the user clicks your "Print" button, then the javascript can attack! the iframe and trigger the print dialog.


Bonus Idea #2 - Extra credit if you disable your "Print" button and give the user a little loading spinner or something after they click it, so that they know something's in process instead of clicking it repeatedly!

Check if a list contains an item in Ansible

You do not need {{}} in when conditions. What you are searching for is:

- fail: msg="unsupported version"
  when: version not in acceptable_versions

Kill python interpeter in linux from the terminal

pgrep -f youAppFile.py | xargs kill -9

pgrep returns the PID of the specific file will only kill the specific application.

How to find out when a particular table was created in Oracle?

Try this query:

SELECT sysdate FROM schema_name.table_name;

This should display the timestamp that you might need.

What is the difference between display: inline and display: inline-block?

All answers above contribute important info on the original question. However, there is a generalization that seems wrong.

It is possible to set width and height to at least one inline element (that I can think of) – the <img> element.

Both accepted answers here and on this duplicate state that this is not possible but this doesn’t seem like a valid general rule.

Example:

_x000D_
_x000D_
img {_x000D_
  width: 200px;_x000D_
  height: 200px;_x000D_
  border: 1px solid red;_x000D_
}
_x000D_
<img src="#" />
_x000D_
_x000D_
_x000D_

The img has display: inline, but its width and height were successfully set.

Accidentally committed .idea directory files into git

You can remove it from the repo and commit the change.

git rm .idea/ -r --cached
git add -u .idea/
git commit -m "Removed the .idea folder"

After that, you can push it to the remote and every checkout/clone after that will be ok.

Remove insignificant trailing zeros from a number?

If you convert it to a string it will not display any trailing zeros, which aren't stored in the variable in the first place since it was created as a Number, not a String.

var n = 1.245000
var noZeroes = n.toString() // "1.245" 

How can I get a specific field of a csv file?

There is an interesting point you need to catch about csv.reader() object. The csv.reader object is not list type, and not subscriptable.

This works:

for r in csv.reader(file_obj): # file not closed
    print r

This does not:

r = csv.reader(file_obj) 
print r[0]

So, you first have to convert to list type in order to make the above code work.

r = list( csv.reader(file_obj) )
print r[0]          

Reading a key from the Web.Config using ConfigurationManager

Sorry I've not tested this but I think it's done like this:

var filemap = new System.Configuration.ExeConfigurationFileMap();            
System.Configuration.Configuration config =  System.Configuration.ConfigurationManager.OpenMappedExeConfiguration(filemap, System.Configuration.ConfigurationUserLevel.None);

//usage: config.AppSettings["xxx"]

Which UUID version to use?

Postgres documentation describes the differences between UUIDs. A couple of them:

V3:

uuid_generate_v3(namespace uuid, name text) - This function generates a version 3 UUID in the given namespace using the specified input name.

V4:

uuid_generate_v4 - This function generates a version 4 UUID, which is derived entirely from random numbers.

JavaScript array to CSV

I created this code for creating a nice, readable csv files:

var objectToCSVRow = function(dataObject) {
    var dataArray = new Array;
    for (var o in dataObject) {
        var innerValue = dataObject[o]===null?'':dataObject[o].toString();
        var result = innerValue.replace(/"/g, '""');
        result = '"' + result + '"';
        dataArray.push(result);
    }
    return dataArray.join(' ') + '\r\n';
}

var exportToCSV = function(arrayOfObjects) {

    if (!arrayOfObjects.length) {
        return;
    }

    var csvContent = "data:text/csv;charset=utf-8,";

    // headers
    csvContent += objectToCSVRow(Object.keys(arrayOfObjects[0]));

    arrayOfObjects.forEach(function(item){
        csvContent += objectToCSVRow(item);
    }); 

    var encodedUri = encodeURI(csvContent);
    var link = document.createElement("a");
    link.setAttribute("href", encodedUri);
    link.setAttribute("download", "customers.csv");
    document.body.appendChild(link); // Required for FF
    link.click();
    document.body.removeChild(link); 
}

In your case, since you use arrays in array instead of objects in array, You will skip the header part, but you could add the column names yourself by putting this instead of that part:

// headers
csvContent += '"Column name 1" "Column name 2" "Column name 3"\n';

The secret is that a space separates the columns in the csv file, and we put the column values in the double quotes to allow spaces, and escape any double quotes in the values themselves.

Also note that I replace null values with empty string, because that suited my needs, but you can change that and replace it with anything you like.

onCreateOptionsMenu inside Fragments

Call

setSupportActionBar(toolbar)

inside

onViewCreated(...) 

of Fragment

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    Toolbar toolbar = (Toolbar) view.findViewById(R.id.toolbar);
    ((MainActivity)getActivity()).setSupportActionBar(toolbar);
    setHasOptionsMenu(true);
}

Angularjs prevent form submission when input validation fails

Change the submit button to:

<button type="submit" ng-disabled="loginform.$invalid">Login</button>

Get the value of a dropdown in jQuery

Another option:

$("#<%=dropDownId.ClientID%>").children("option:selected").val();

vertical-align: middle doesn't work

You should set a fixed value to your span's line-height property:

.float, .twoline {
    line-height: 100px;
}

Webpack - webpack-dev-server: command not found

I found the accepted answer does not work in all scenarios. To ensure it 100% works one must ALSO clear the npm cache. Either directly Goto the cache and clear locks, caches, anonymous-cli-metrics.json; or one can try npm cache clean.

Since the author had cleared the cache before trying the recommended solution its possible that failed to make it part of the pre-requisites.

JQuery DatePicker ReadOnly

I came up with another solution that is different than what had been proposed. When the date picker is used, it creates a div similar to a pop-up that is positioned when the input field is clicked on. To remove it, I just set the visibility property of the CSS so that it doesn't show up.

if ($('.yourDatepickerSelector').prop('readonly')) {
    $('#ui-datepicker-div').css({ 'visibility': 'hidden' })
} else { $('#ui-datepicker-div').css({ 'visibility': 'visible' }) }

This also seems to post correctly to the server, and should not effect any of the settings associated with it.

ToggleButton in C# WinForms

You can always code your own button with custom graphics and a PictureBox, though it won't necessarily match the Windows theme of your users.

Local package.json exists, but node_modules missing

This issue can also raise when you change your system password but not the same updated on your .npmrc file that exist on path C:\Users\user_name, so update your password there too.

please check on it and run npm install first and then npm start.

How can I parse a JSON file with PHP?

The most elegant solution:

$shipments = json_decode(file_get_contents("shipments.js"), true);
print_r($shipments);

Remember that the json-file has to be encoded in UTF-8 without BOM. If the file has BOM, then json_decode will return NULL.

Alternatively:

$shipments = json_encode(json_decode(file_get_contents("shipments.js"), true));
echo $shipments;

Migrating from VMWARE to VirtualBox

Note: I am not sure this will be of any help to you, but you never know.

I found this link:http://www.ubuntugeek.com/howto-convert-vmware-image-to-virtualbox-image.html

ENJOY :-)

DELETE_FAILED_INTERNAL_ERROR Error while Installing APK

You need rebuild the project

If using Android Studio 2.3:

Build -> Rebuild Project

Even if after that your app start with a error just rebuild the project again:

Build -> Rebuild Project

How do you loop in a Windows batch file?

From FOR /? help doc:

FOR %variable IN (set) DO command [command-parameters]

%variable Specifies a single letter replaceable parameter.
(set) Specifies a set of one or more files. Wildcards may be used. command Specifies the command to carry out for each file.
command-parameters
Specifies parameters or switches for the specified command.

To use the FOR command in a batch program, specify %%variable instead
of %variable. Variable names are case sensitive, so %i is different
from %I.

If Command Extensions are enabled, the following additional
forms of the FOR command are supported:

FOR /D %variable IN (set) DO command [command-parameters]

If set contains wildcards, then specifies to match against directory  
names instead of file names.                                          

FOR /R [[drive:]path] %variable IN (set) DO command [command-parameters]

Walks the directory tree rooted at [drive:]path, executing the FOR    
statement in each directory of the tree.  If no directory             
specification is specified after /R then the current directory is     
assumed.  If set is just a single period (.) character then it        
will just enumerate the directory tree.                               

FOR /L %variable IN (start,step,end) DO command [command-parameters]

The set is a sequence of numbers from start to end, by step amount.   
So (1,1,5) would generate the sequence 1 2 3 4 5 and (5,-1,1) would   
generate the sequence (5 4 3 2 1)                                     

What is the difference between origin and upstream on GitHub?

after cloning a fork you have to explicitly add a remote upstream, with git add remote "the original repo you forked from". This becomes your upstream, you mostly fetch and merge from your upstream. Any other business such as pushing from your local to upstream should be done using pull request.

How to assign text size in sp value using java code

semeTextView.setTextSize(TypedValue.COMPLEX_UNIT_PX, 
                       context.getResources().getDimension(R.dimen.text_size_in_dp))

How to extract file name from path?

I needed the path, not the filename.

So to extract the file path in code:

JustPath = Left(sFileP, Len(sFileP) - Len(Split(sFileP, "\")(UBound(Split(sFileP, "\"))))) 

How do I add a library (android-support-v7-appcompat) in IntelliJ IDEA

Using Gradle

If you are using Gradle, you can add it as a compile dependency.

Instructions

  1. Make sure you have the Android Support Repository SDK package installed. Android Studio automatically recognizes this repository during the build process (not sure about plain IntelliJ).

    Android Support Repository

  2. Add the dependency to {project}/build.gradle

    dependencies {
        compile 'com.android.support:appcompat-v7:+'
    }
    
  3. Click the Sync Project with Gradle Files button.

EDIT: Looks like these same instructions are on the documentation under Adding libraries with resources -> Using Android Studio.

How to increase storage for Android Emulator? (INSTALL_FAILED_INSUFFICIENT_STORAGE)

Update

This answer is, as I write this, nearly eight years old, and about five years stale. But it's still (as I write this) the "accepted" answer, because it answered the question when it was asked.

The newer answer, that applies to the newer Android Studio tools, can be found here: https://stackoverflow.com/a/35828035/62 -- it's a great answer with screen shots. If you're using Android Studio, ignore the Eclipse answer below.

Original Eclipse-based Answer

I was searching for the answer to this question, and was unsatisfied with the above answers. But then I found the answer, so here it is for future reference:

To summarize (and clarify), in Eclipse, go to "Debug Configurations". You can find that in the drop-down under the "debug" icon. Select "target", and select a preferred emulator target to launch. Then under "additional emulator command line options," add this:

-partition-size 1024

Then CLOSE the emulator (and remove any devices), and click the debug icon, which will launch the preferred emulator you selected. This is important: Eclipse needs to launch the debugger, not AVD.

That fixed the problem for me.

C#: How do you edit items and subitems in a listview?

Sorry, don't have enough rep, or would have commented on CraigTP's answer.

I found the solution from the 1st link - C# Editable ListView, quite easy to use. The general idea is to:

  • identify the SubItem that was selected and overlay a TextBox with the SubItem's text over the SubItem
  • give this TextBox focus
  • change SubItem's text to that of TextBox's when TextBox loses focus

What a workaround for a seemingly simple operation :-|

Count if two criteria match - EXCEL formula

If youR data was in A1:C100 then:

Excel - all versions

=SUMPRODUCT(--(A1:A100="M"),--(C1:C100="Yes"))

Excel - 2007 onwards

=COUNTIFS(A1:A100,"M",C1:C100,"Yes")

How to recover just deleted rows in mysql?

If you use MyISAM tables, then you can recover any data you deleted, just

open file: mysql/data/[your_db]/[your_table].MYD

with any text editor

Setting a PHP $_SESSION['var'] using jQuery

Similar to Luke's answer, but with GET.

Place this php-code in a php-page, ex. getpage.php:

<?php
$_SESSION['size'] = $_GET['size'];
?>

Then call it with a jQuery script like this:

$.get( "/getpage.php?size=1");

Agree with Federico. In some cases you may run into problems using POST, although not sure if it can be browser related.

How to import Google Web Font in CSS file?

We can easily do that in css3. We have to simply use @import statement. The following video easily describes the way how to do that. so go ahead and watch it out.

https://www.youtube.com/watch?v=wlPr6EF6GAo

How to generate a number of most distinctive colors in R?

I joined all qualitative palettes from RColorBrewer package. Qualitative palettes are supposed to provide X most distinctive colours each. Of course, mixing them joins into one palette also similar colours, but that's the best I can get (74 colors).

library(RColorBrewer)
n <- 60
qual_col_pals = brewer.pal.info[brewer.pal.info$category == 'qual',]
col_vector = unlist(mapply(brewer.pal, qual_col_pals$maxcolors, rownames(qual_col_pals)))
pie(rep(1,n), col=sample(col_vector, n))

colour_Brewer_qual_60

Other solution is: take all R colors from graphical devices and sample from them. I removed shades of grey as they are too similar. This gives 433 colors

color = grDevices::colors()[grep('gr(a|e)y', grDevices::colors(), invert = T)]

set of 20 colours

pie(rep(1,n), col=sample(color, n))

with 200 colors n = 200:

pie(rep(1,n), col=sample(color, n))

set of 200 colours

Dump a list in a pickle file and retrieve it back later

Pickling will serialize your list (convert it, and it's entries to a unique byte string), so you can save it to disk. You can also use pickle to retrieve your original list, loading from the saved file.

So, first build a list, then use pickle.dump to send it to a file...

Python 3.4.1 (default, May 21 2014, 12:39:51) 
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.2.79)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> mylist = ['I wish to complain about this parrot what I purchased not half an hour ago from this very boutique.', "Oh yes, the, uh, the Norwegian Blue...What's,uh...What's wrong with it?", "I'll tell you what's wrong with it, my lad. 'E's dead, that's what's wrong with it!", "No, no, 'e's uh,...he's resting."]
>>> 
>>> import pickle
>>> 
>>> with open('parrot.pkl', 'wb') as f:
...   pickle.dump(mylist, f)
... 
>>> 

Then quit and come back later… and open with pickle.load...

Python 3.4.1 (default, May 21 2014, 12:39:51) 
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.2.79)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import pickle
>>> with open('parrot.pkl', 'rb') as f:
...   mynewlist = pickle.load(f)
... 
>>> mynewlist
['I wish to complain about this parrot what I purchased not half an hour ago from this very boutique.', "Oh yes, the, uh, the Norwegian Blue...What's,uh...What's wrong with it?", "I'll tell you what's wrong with it, my lad. 'E's dead, that's what's wrong with it!", "No, no, 'e's uh,...he's resting."]
>>>

How to cancel a Task in await?

One case which hasn't been covered is how to handle cancellation inside of an async method. Take for example a simple case where you need to upload some data to a service get it to calculate something and then return some results.

public async Task<Results> ProcessDataAsync(MyData data)
{
    var client = await GetClientAsync();
    await client.UploadDataAsync(data);
    await client.CalculateAsync();
    return await client.GetResultsAsync();
}

If you want to support cancellation then the easiest way would be to pass in a token and check if it has been cancelled between each async method call (or using ContinueWith). If they are very long running calls though you could be waiting a while to cancel. I created a little helper method to instead fail as soon as canceled.

public static class TaskExtensions
{
    public static async Task<T> WaitOrCancel<T>(this Task<T> task, CancellationToken token)
    {
        token.ThrowIfCancellationRequested();
        await Task.WhenAny(task, token.WhenCanceled());
        token.ThrowIfCancellationRequested();

        return await task;
    }

    public static Task WhenCanceled(this CancellationToken cancellationToken)
    {
        var tcs = new TaskCompletionSource<bool>();
        cancellationToken.Register(s => ((TaskCompletionSource<bool>)s).SetResult(true), tcs);
        return tcs.Task;
    }
}

So to use it then just add .WaitOrCancel(token) to any async call:

public async Task<Results> ProcessDataAsync(MyData data, CancellationToken token)
{
    Client client;
    try
    {
        client = await GetClientAsync().WaitOrCancel(token);
        await client.UploadDataAsync(data).WaitOrCancel(token);
        await client.CalculateAsync().WaitOrCancel(token);
        return await client.GetResultsAsync().WaitOrCancel(token);
    }
    catch (OperationCanceledException)
    {
        if (client != null)
            await client.CancelAsync();
        throw;
    }
}

Note that this will not stop the Task you were waiting for and it will continue running. You'll need to use a different mechanism to stop it, such as the CancelAsync call in the example, or better yet pass in the same CancellationToken to the Task so that it can handle the cancellation eventually. Trying to abort the thread isn't recommended.

Automatic Preferred Max Layout Width is not available on iOS versions prior to 8.0

I had this issue and was able to fix it by adding constraints to determine the max with for a label.

When dropping a multiline label in there is not constraint set to enforce the width inside the parent view. This is where the new PreferredMaxWidth comes into play. On iOS 7 and earlier you have to define the max width yourself. I simply added a 10px constraint to the left and right hand side of the label.

You can also add a <= width constraint which also fixes the issue.

So this is not actually a bug, you simply have to define the max width yourself. The explicit option mention in other answer will also work as you are setting this width value however you will have to modify this value if you want the max width to change based on the parent width (as you have explicitly set the width).

My above solution ensures the width is always maintained no matter how big the parent view is.

Best ways to teach a beginner to program?

Some additional information that someone could attach to Jason Pratt's earlier post on Alice ... specifically, a Storytelling Alice variant.

Although the study presented targets middle school girls, you may find the white paper written by Caitlin Kelleher interesting.

How to properly export an ES6 class in Node 4?

Use

// aspect-type.js
class AspectType {

}

export default AspectType;

Then to import it

// some-other-file.js
import AspectType from './aspect-type';

Read http://babeljs.io/docs/learn-es2015/#modules for more details

Is it possible to modify a registry entry via a .bat/.cmd script?

Yes. You can use reg.exe which comes with the OS to add, delete or query registry values. Reg.exe does not have an explicit modify command, but you can do it by doing delete and then add.

How to compare pointers?

The == operator on pointers will compare their numeric address and hence determine if they point to the same object.

Should I use window.navigate or document.location in JavaScript?

support for document.location is also good though its a deprecated method. I've been using this method for a while with no problems. you can refer here for more details:

https://developer.mozilla.org/en-US/docs/Web/API/document.location

Difference between core and processor

I have read all answers, but this link was more clear explanation for me about difference between CPU(Processor) and Core. So I'm leaving here some notes from there.

The main difference between CPU and Core is that the CPU is an electronic circuit inside the computer that carries out instruction to perform arithmetic, logical, control and input/output operations while the core is an execution unit inside the CPU that receives and executes instructions.

enter image description here

Pandas groupby month and year

You can use either resample or Grouper (which resamples under the hood).

First make sure that the datetime column is actually of datetimes (hit it with pd.to_datetime). It's easier if it's a DatetimeIndex:

In [11]: df1
Out[11]:
            abc  xyz
Date
2013-06-01  100  200
2013-06-03  -20   50
2013-08-15   40   -5
2014-01-20   25   15
2014-02-21   60   80

In [12]: g = df1.groupby(pd.Grouper(freq="M"))  # DataFrameGroupBy (grouped by Month)

In [13]: g.sum()
Out[13]:
            abc  xyz
Date
2013-06-30   80  250
2013-07-31  NaN  NaN
2013-08-31   40   -5
2013-09-30  NaN  NaN
2013-10-31  NaN  NaN
2013-11-30  NaN  NaN
2013-12-31  NaN  NaN
2014-01-31   25   15
2014-02-28   60   80

In [14]: df1.resample("M", how='sum')  # the same
Out[14]:
            abc  xyz
Date
2013-06-30   40  125
2013-07-31  NaN  NaN
2013-08-31   40   -5
2013-09-30  NaN  NaN
2013-10-31  NaN  NaN
2013-11-30  NaN  NaN
2013-12-31  NaN  NaN
2014-01-31   25   15
2014-02-28   60   80

Note: Previously pd.Grouper(freq="M") was written as pd.TimeGrouper("M"). The latter is now deprecated since 0.21.


I had thought the following would work, but it doesn't (due to as_index not being respected? I'm not sure.). I'm including this for interest's sake.

If it's a column (it has to be a datetime64 column! as I say, hit it with to_datetime), you can use the PeriodIndex:

In [21]: df
Out[21]:
        Date  abc  xyz
0 2013-06-01  100  200
1 2013-06-03  -20   50
2 2013-08-15   40   -5
3 2014-01-20   25   15
4 2014-02-21   60   80

In [22]: pd.DatetimeIndex(df.Date).to_period("M")  # old way
Out[22]:
<class 'pandas.tseries.period.PeriodIndex'>
[2013-06, ..., 2014-02]
Length: 5, Freq: M

In [23]: per = df.Date.dt.to_period("M")  # new way to get the same

In [24]: g = df.groupby(per)

In [25]: g.sum()  # dang not quite what we want (doesn't fill in the gaps)
Out[25]:
         abc  xyz
2013-06   80  250
2013-08   40   -5
2014-01   25   15
2014-02   60   80

To get the desired result we have to reindex...

How to add buttons like refresh and search in ToolBar in Android?

Add this line at the top:

"xmlns:app="http://schemas.android.com/apk/res-auto"

and then use:

app:showasaction="ifroom"

Two column div layout with fluid left and fixed right column

The following examples are source ordered i.e. column 1 appears before column 2 in the HTML source. Whether a column appears on left or right is controlled by CSS:

Fixed Right

_x000D_
_x000D_
#wrapper {_x000D_
  margin-right: 200px;_x000D_
}_x000D_
#content {_x000D_
  float: left;_x000D_
  width: 100%;_x000D_
  background-color: #CCF;_x000D_
}_x000D_
#sidebar {_x000D_
  float: right;_x000D_
  width: 200px;_x000D_
  margin-right: -200px;_x000D_
  background-color: #FFA;_x000D_
}_x000D_
#cleared {_x000D_
  clear: both;_x000D_
}
_x000D_
<div id="wrapper">_x000D_
  <div id="content">Column 1 (fluid)</div>_x000D_
  <div id="sidebar">Column 2 (fixed)</div>_x000D_
  <div id="cleared"></div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Fixed Left

_x000D_
_x000D_
#wrapper {_x000D_
  margin-left: 200px;_x000D_
}_x000D_
#content {_x000D_
  float: right;_x000D_
  width: 100%;_x000D_
  background-color: #CCF;_x000D_
}_x000D_
#sidebar {_x000D_
  float: left;_x000D_
  width: 200px;_x000D_
  margin-left: -200px;_x000D_
  background-color: #FFA;_x000D_
}_x000D_
#cleared {_x000D_
  clear: both;_x000D_
}
_x000D_
<div id="wrapper">_x000D_
  <div id="content">Column 1 (fluid)</div>_x000D_
  <div id="sidebar">Column 2 (fixed)</div>_x000D_
  <div id="cleared"></div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Alternate solution is to use display: table-cell; which results in equal height columns.

How to properly upgrade node using nvm

if you have 4.2 and want to install 5.0.0 then

nvm install v5.0.0 --reinstall-packages-from=4.2

the answer of gabrielperales is right except that he missed the "=" sign at the end. if you don't put the "=" sign then new node version will be installed but the packages won't be installed.

source: sitepoint

grep a tab in UNIX

+1 way, that works in ksh, dash, etc: use printf to insert TAB:

grep "$(printf 'BEGIN\tEND')" testfile.txt

linq where list contains any in list

Or like this

class Movie
{
  public string FilmName { get; set; }
  public string Genre { get; set; }
}

...

var listofGenres = new List<string> { "action", "comedy" };

var Movies = new List<Movie> {new Movie {Genre="action", FilmName="Film1"},
                new Movie {Genre="comedy", FilmName="Film2"},
                new Movie {Genre="comedy", FilmName="Film3"},
                new Movie {Genre="tragedy", FilmName="Film4"}};

var movies = Movies.Join(listofGenres, x => x.Genre, y => y, (x, y) => x).ToList();

CSS3 selector :first-of-type with class name?

This is an old thread, but I'm responding because it still appears high in the list of search results. Now that the future has arrived, you can use the :nth-child pseudo-selector.

p:nth-child(1) { color: blue; }
p.myclass1:nth-child(1) { color: red; }
p.myclass2:nth-child(1) { color: green; }

The :nth-child pseudo-selector is powerful - the parentheses accept formulas as well as numbers.

More here: https://developer.mozilla.org/en-US/docs/Web/CSS/:nth-child

How do I call paint event?

I found the Invalidate() creating too much of flickering. Here's my situation. A custom control I am developing draws its whole contents via handling the Paint event.

this.Paint += this.OnPaint;

This handler calls a custom routine that does the actual painting.

private void OnPaint(object sender, PaintEventArgs e)
{
    this.DrawFrame(e.Graphics);
}

To simulate scrolling I want to repaint my control every time the cursor moves while the left mouse button is pressed. My first choice was using the Invalidate() like the following.

private void RedrawFrame()
{
    var r = new Rectangle(
        0, 0, this.Width, this.Height);

    this.Invalidate(r);
    this.Update();
}

The control scrolls OK but flickers far beyond any comfortable level. So I decided, instead of repainting the control, to call my custom DrawFrame() method directly after handling the MouseMove event. That produced a smooth scrolling with no flickering.

private void RedrawFrame()
{
    var g = Graphics.FromHwnd(this.Handle);
    this.DrawFrame(g);
}

This approach may not be applicable to all situations, but so far it suits me well.

How to check that an element is in a std::set?

Write your own:

template<class T>
bool checkElementIsInSet(const T& elem, const std::set<T>& container)
{
  return container.find(elem) != container.end();
}

How to display (print) vector in Matlab?

Here is a more generalized solution that prints all elements of x the vector x in this format:

x=randperm(3);
s = repmat('%d,',1,length(x));
s(end)=[]; %Remove trailing comma

disp(sprintf(['Answer: (' s ')'], x))

How do I make JavaScript beep?

Using CSS you can do it if you add the following style to a tag, but you will need a wav file:

<style type="text/css">
        .beep {cue: url("beep.wav") }
</style>

var body=document.getElementByTagName("body");
body.className=body.className + " " + "beep";

cURL not working (Error #77) for SSL connections on CentOS for non-root users

Turns out that the problem was with face that the script was running from a cPanel "email piped to script", so was running as the user, so is was a user problem, but was not affecting the web server at all.

The cause for the user not being able to access the /etc/pki directory was due to them only having jailed ssh access. Once I granted full access, it all worked fine.

Thanks for the info though, Remi.

How do I iterate over a range of numbers defined by variables in Bash?

If you need it prefix than you might like this

 for ((i=7;i<=12;i++)); do echo `printf "%2.0d\n" $i |sed "s/ /0/"`;done

that will yield

07
08
09
10
11
12

how to configure hibernate config file for sql server

We also need to mention default schema for SQSERVER: dbo

<property name="hibernate.default_schema">dbo</property>

Tested with hibernate 4

Streaming via RTSP or RTP in HTML5

The spirit of the question, I think, was not truly answered. No, you cannot use a video tag to play rtsp streams as of now. The other answer regarding the link to Chromium guy's "never" is a bit misleading as the linked thread / answer is not directly referring to Chrome playing rtsp via the video tag. Read the entire linked thread, especially the comments at the very bottom and links to other threads.

The real answer is this: No, you cannot just put a video tag on an html 5 page and play rtsp. You need to use a Javascript library of some sort (unless you want to get into playing things with flash and silverlight players) to play streaming video. {IMHO} At the rate the html 5 video discussion and implementation is going, the various vendors of proprietary video standards are not interested in helping this move forward so don't count of the promised ease of use of the video tag unless the browser makers take it upon themselves to somehow solve the problem...again, not likely.{/IMHO}

React Native: Possible unhandled promise rejection

In My case, I am running a local Django backend in IP 127.0.0.1:8000 with Expo start. Just make sure you have the server in public domain not hosted lcoally on your machine

Get List of connected USB Devices

This is a much simpler example for people only looking for removable usb drives.

using System.IO;

foreach (DriveInfo drive in DriveInfo.GetDrives())
{
    if (drive.DriveType == DriveType.Removable)
    {
        Console.WriteLine(string.Format("({0}) {1}", drive.Name.Replace("\\",""), drive.VolumeLabel));
    }
}

Java generics: multiple generic parameters?

Yes - it's possible (though not with your method signature) and yes, with your signature the types must be the same.

With the signature you have given, T must be associated to a single type (e.g. String or Integer) at the call-site. You can, however, declare method signatures which take multiple type parameters

public <S, T> void func(Set<S> s, Set<T> t)

Note in the above signature that I have declared the types S and T in the signature itself. These are therefore different to and independent of any generic types associated with the class or interface which contains the function.

public class MyClass<S, T> {
   public        void foo(Set<S> s, Set<T> t); //same type params as on class
   public <U, V> void bar(Set<U> s, Set<V> t); //type params independent of class
}

You might like to take a look at some of the method signatures of the collection classes in the java.util package. Generics is really rather a complicated subject, especially when wildcards (? extends and ? super) are considered. For example, it's often the case that a method which might take a Set<Number> as a parameter should also accept a Set<Integer>. In which case you'd see a signature like this:

public void baz(Set<? extends T> s);

There are plenty of questions already on SO for you to look at on the subject!

Not sure what the point of returning an int from the function is, although you could do that if you want!

How to get JSON from URL in JavaScript?

Axios is a promise based HTTP client for the browser and node.js.

It offers automatic transforms for JSON data and it's the official recommendation from the Vue.js team when migrating from the 1.0 version which included a REST client by default.

Performing a GET request

// Make a request for a user with a given ID
axios.get('http://query.yahooapis.com/v1/publ...')
  .then(function (response) {
    console.log(response);
  })
  .catch(function (error) {
    console.log(error);
  });

Or even just axios(url) is enough as a GET request is the default.

Removing the first 3 characters from a string

Just use substring: "apple".substring(3); will return le

java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState

My app has a fragment to loading in 3 secs, but when the fist screen is preparing to show, I press home button and resume run it, it show the same error, so It edit my code and it ran very smooth:

new Handler().post(new Runnable() {
        public void run() {
            if (saveIns == null) {
                mFragment = new Fragment_S1_loading();
                getFragmentManager().beginTransaction()
                        .replace(R.id.container, mFragment).commit();
            }
            getActionBar().hide();
            // Loading screen in 3 secs:
            mCountDownTimerLoading = new CountDownTimer(3000, 1000) {

                @Override
                public void onTick(long millisUntilFinished) {

                }

                @Override
                public void onFinish() {
                    if (saveIns == null) {// TODO bug when start app and press home
                                            // button
                        getFragmentManager()
                                .beginTransaction()
                                .replace(R.id.container,
                                        new Fragment_S2_sesstion1()).commitAllowingStateLoss();
                    }
                    getActionBar().show();
                }
            }.start();
        }
    });

NOTE: add commitAllowingStateLoss() instead of commit()

Can an ASP.NET MVC controller return an Image?

You could use the HttpContext.Response and directly write the content to it (WriteFile() might work for you) and then return ContentResult from your action instead of ActionResult.

Disclaimer: I have not tried this, it's based on looking at the available APIs. :-)

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space

I don't know about javax.media.j3d, so I might be mistaken, but you usually want to investigate whether there is a memory leak. Well, as others note, if it was 64MB and you are doing something with 3d, maybe it's obviously too small...

But if I were you, I'll set up a profiler or visualvm, and let your application run for extended time (days, weeks...). Then look at the heap allocation history, and make sure it's not a memory leak.

If you use a profiler, like JProfiler or the one that comes with NetBeans IDE etc., you can see what object is being accumulating, and then track down what's going on.. Well, almost always something is incorrectly not removed from a collection...

How to import jquery using ES6 syntax?

import {jQuery as $} from 'jquery';

How to create a custom navigation drawer in android

You can easily customize the android Navigation drawer once you know how its implemented. here is a nice tutorial where you can set it up.

This will be the structure of your mainXML:

<android.support.v4.widget.DrawerLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <!-- Framelayout to display Fragments -->
    <FrameLayout
        android:id="@+id/frame_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <!-- Listview to display slider menu -->
    <ListView
        android:id="@+id/list_slidermenu"
        android:layout_width="240dp"
        android:layout_height="match_parent"
        android:layout_gravity="right"
        android:choiceMode="singleChoice"
        android:divider="@color/list_divider"
        android:dividerHeight="1dp"        
        android:listSelector="@drawable/list_selector"
        android:background="@color/list_background"/>
</android.support.v4.widget.DrawerLayout>

You can customize this listview to your liking by adding the header. And radiobuttons.

How to start http-server locally

To start server locally paste the below code in package.json and run npm start in command line.

"scripts": { "start": "http-server -c-1 -p 8081" },

How to read a config file using python

In order to use my example,Your file "abc.txt" needs to look like:

[your-config]
path1 = "D:\test1\first"
path2 = "D:\test2\second"
path3 = "D:\test2\third"

Then in your software you can use the config parser:

import ConfigParser

and then in you code:

 configParser = ConfigParser.RawConfigParser()   
 configFilePath = r'c:\abc.txt'
 configParser.read(configFilePath)

Use case:

self.path = configParser.get('your-config', 'path1')

*Edit (@human.js)

in python 3, ConfigParser is renamed to configparser (as described here)

Objective-C : BOOL vs bool

As mentioned above, BOOL is a signed char. bool - type from C99 standard (int).

BOOL - YES/NO. bool - true/false.

See examples:

bool b1 = 2;
if (b1) printf("REAL b1 \n");
if (b1 != true) printf("NOT REAL b1 \n");

BOOL b2 = 2;
if (b2) printf("REAL b2 \n");
if (b2 != YES) printf("NOT REAL b2 \n");

And result is

REAL b1
REAL b2
NOT REAL b2

Note that bool != BOOL. Result below is only ONCE AGAIN - REAL b2

b2 = b1;
if (b2) printf("ONCE AGAIN - REAL b2 \n");
if (b2 != true) printf("ONCE AGAIN - NOT REAL b2 \n");

If you want to convert bool to BOOL you should use next code

BOOL b22 = b1 ? YES : NO; //and back - bool b11 = b2 ? true : false;

So, in our case:

BOOL b22 = b1 ? 2 : NO;
if (b22)    printf("ONCE AGAIN MORE - REAL b22 \n");
if (b22 != YES) printf("ONCE AGAIN MORE- NOT REAL b22 \n");

And so.. what we get now? :-)

Text not wrapping inside a div element

The problem in the jsfiddle is that your dummy text is all one word. If you use your lorem ipsum given in the question, then the text wraps fine.

If you want large words to be broken mid-word and wrap around, add this to your .title css:

word-wrap: break-word;

Run a Command Prompt command from Desktop Shortcut

Yes. One option you have is to create a batch file containing the command

cmd -c {your command}

or

cmd -k {your command}

The shortcut will then be to this batch file.

Refresh image with a new one at the same url

I had this same issue using the Unsplash random image feature. The idea of adding a dummy query string to the end of the URL is correct, but in this instance a completely random parameter doesn't work (I tried it). I can imagine it's the same for some other services too, but for unsplash the parameter needs to be sig, so your image URL would be, for example, http://example.net/image.jpg?sig=RANDOM where random is a random string that will NOT be the same when you update it. I used Math.random()*100 but date is suitable too.

You need to do the above because without it, the browser will see that the image at said path has already been loaded, and will use that cached image to speed up loading.

See https://github.com/unsplash/unsplash-source-js/issues/9

How to search in array of object in mongodb

as explained in above answers Also, to return only one field from the entire array you can use projection into find. and use $

db.getCollection("sizer").find(
  { awards: { $elemMatch: { award: "National Medal", year: 1975 } } },
  { "awards.$": 1, name: 1 }
);

will be reutrn

{
    _id: 1,
    name: {
        first: 'John',
        last: 'Backus'
    },
    awards: [
        {
            award: 'National Medal',
            year: 1975,
            by: 'NSF'
        }
    ]
}

git cherry-pick says "...38c74d is a merge but no -m option was given"

-m means the parent number.

From the git doc:

Usually you cannot cherry-pick a merge because you do not know which side of the merge should be considered the mainline. This option specifies the parent number (starting from 1) of the mainline and allows cherry-pick to replay the change relative to the specified parent.

For example, if your commit tree is like below:

- A - D - E - F -   master
   \     /
    B - C           branch one

then git cherry-pick E will produce the issue you faced.

git cherry-pick E -m 1 means using D-E, while git cherry-pick E -m 2 means using B-C-E.

How to change font-color for disabled input?

This works for making disabled select options act as headers. It doesnt remove the default text shadow of the :disabled option but it does remove the hover effect. In IE you wont get the font color but at least the text-shadow is gone. Here is the html and css:

_x000D_
_x000D_
select option.disabled:disabled{color: #5C3333;background-color: #fff;font-weight: bold;}_x000D_
select option.disabled:hover{color:  #5C3333 !important;background-color: #fff;}_x000D_
select option:hover{color: #fde8c4;background-color: #5C3333;}
_x000D_
<select>_x000D_
     <option class="disabled" disabled>Header1</option>_x000D_
     <option>Item1</option>_x000D_
     <option>Item1</option>_x000D_
     <option>Item1</option>_x000D_
     <option class="disabled" disabled>Header2</option>_x000D_
     <option>Item2</option>_x000D_
     <option>Item2</option>_x000D_
     <option>Item2</option>_x000D_
     <option class="disabled" disabled>Header3</option>_x000D_
     <option>Item3</option>_x000D_
     <option>Item3</option>_x000D_
     <option>Item3</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_

Angular (4, 5, 6, 7) - Simple example of slide in out animation on ngIf

Actually the minimum amount of Angular to be used (as requested in the original question) is just adding a class to the DOM element when show variable is true, and perform the animation/transition via CSS.

So your minimum Angular code is this:

<div class="box-opener" (click)="show = !show">
    Open/close the box
</div>

<div class="box" [class.opened]="show">
    <!-- Content -->
</div>

With this solution, you need to create CSS rules for the transition, something like this:

.box {
    background-color: #FFCC55;
    max-height: 0px;
    overflow-y: hidden;
    transition: ease-in-out 400ms max-height;
}

.box.opened {
    max-height: 500px;
    transition: ease-in-out 600ms max-height;
}

If you have retro-browser-compatibility issues, just remember to add the vendor prefixes in the transitions.

See the example here

What port is used by Java RMI connection?

If you can modify the client, then have it print out the remote reference and you will see what port it's using. E.g.

ServerApi server = (ServerApi) registry.lookup(ServerApi.RMI_NAME);
System.out.println("Got server handle " + server);

will produce something like:

Got server handle Proxy[ServerApi,RemoteObjectInvocationHandler[UnicastRef [liveRef: [endpoint:172.17.3.190:9001,objID:[-7c63fea8:...

where you can see the port is 9001. If the remote class is not specifying the port, then it will change across reboots. If you want to use a fixed port then you need to make sure the remote class constructor does something like:

super(rmiPort)

How to know which is running in Jupyter notebook?

from platform import python_version

print(python_version())

This will give you the exact version of python running your script. eg output:

3.6.5

How to enable CORS in AngularJs

I encountered a similar problem like this, problem was with the backend . I was using node server(Express). I had a get request from the frontend(angular) as shown below

   onGetUser(){
        return this.http.get("http://localhost:3000/user").pipe(map(
            (response:Response)=>{
                const user =response.json();
                return user;
            }
        )) 
    }

But it gave the following errorThe error

This is the backend code written using express without the headers

app.get('/user',async(req,res)=>{
     const user=await getuser();
     res.send(user);
 })

After adding a header to the method problem was solved

app.get('/user',async(req,res)=>{
    res.header("Access-Control-Allow-Origin", "*");
    const user=await getuser();
    res.send(user);
})

You can get more details about Enabling CORS on Node JS

What's the difference between an Angular component and module

Components control views (html). They also communicate with other components and services to bring functionality to your app.

Modules consist of one or more components. They do not control any html. Your modules declare which components can be used by components belonging to other modules, which classes will be injected by the dependency injector and which component gets bootstrapped. Modules allow you to manage your components to bring modularity to your app.

How to kill MySQL connections

As above mentioned, there is no special command to do it. However, if all those connection are inactive, using 'flush tables;' is able to release all those connection which are not active.

How to get the html of a div on another page with jQuery ajax?

Ok, You should "construct" the html and find the .content div.

like this:

$.ajax({
   url:href,
   type:'GET',
   success: function(data){
       $('#content').html($(data).find('#content').html());
   }
});

Simple!

Ignore parent padding

easy fix.. add to parent div:

box-sizing: border-box;

How to 'grep' a continuous stream?

I think that your problem is that grep uses some output buffering. Try

tail -f file | stdbuf -o0 grep my_pattern

it will set output buffering mode of grep to unbuffered.

VBA Public Array : how to?

This worked for me, seems to work as global :

Dim savePos(2 To 8) As Integer

And can call it from every sub, for example getting first element :

MsgBox (savePos(2))

What is the 'override' keyword in C++ used for?

The override keyword serves two purposes:

  1. It shows the reader of the code that "this is a virtual method, that is overriding a virtual method of the base class."
  2. The compiler also knows that it's an override, so it can "check" that you are not altering/adding new methods that you think are overrides.

To explain the latter:

class base
{
  public:
    virtual int foo(float x) = 0; 
};


class derived: public base
{
   public:
     int foo(float x) override { ... } // OK
}

class derived2: public base
{
   public:
     int foo(int x) override { ... } // ERROR
};

In derived2 the compiler will issue an error for "changing the type". Without override, at most the compiler would give a warning for "you are hiding virtual method by same name".

Laravel: Using try...catch with DB::transaction()

I've decided to give an answer to this question because I think it can be solved using a simpler syntax than the convoluted try-catch block. The Laravel documentation is pretty brief on this subject.

Instead of using try-catch, you can just use the DB::transaction(){...} wrapper like this:

// MyController.php
public function store(Request $request) {
    return DB::transaction(function() use ($request) {
        $user = User::create([
            'username' => $request->post('username')
        ]);

        // Add some sort of "log" record for the sake of transaction:
        $log = Log::create([
            'message' => 'User Foobar created'
        ]);

        // Lets add some custom validation that will prohibit the transaction:
        if($user->id > 1) {
            throw AnyException('Please rollback this transaction');
        }

        return response()->json(['message' => 'User saved!']);
    });
};

You should then see that the User and the Log record cannot exist without eachother.

Some notes on the implementation above:

  • Make sure to return the transaction, so that you can use the response() you return within its callback.
  • Make sure to throw an exception if you want the transaction to be rollbacked (or have a nested function that throws the exception for you automatically, like an SQL exception from within Eloquent).
  • The id, updated_at, created_at and any other fields are AVAILABLE AFTER CREATION for the $user object (for the duration of this transaction). The transaction will run through any of the creation logic you have. HOWEVER, the whole record is discarded when the AnyException is thrown. This means that for instance an auto-increment column for id does get incremented on failed transactions.

Tested on Laravel 5.8

best way to get the key of a key/value javascript object

There is no way other than for ... in. If you don't want to use that (parhaps because it's marginally inefficient to have to test hasOwnProperty on each iteration?) then use a different construct, e.g. an array of kvp's:

[{ key: 'key', value: 'value'}, ...]

Explanation of the UML arrows

The accepted answer being said, It is missing some explanations. For example, what is the difference between a uni-directional and a bi-directional association? In the provided example, both do exist. ( Both '5's in the arrows)

If looking for a more complete answer and have more time, here is a thorough explanation.

Reset select2 value and show placeholder

The DOM interface, already keeps track of the initial state...

So doing the following is enough:

$("#reset").on("click", function () {
    $('#my_select option').prop('selected', function() {
        return this.defaultSelected;
    });
});

SyntaxError: cannot assign to operator

Well, as the error says, you have an expression (((t[1])/length) * t[1]) on the left side of the assignment, rather than a variable name. You have that expression, and then you tell Python to add string to it (which is always "") and assign it to... where? ((t[1])/length) * t[1] isn't a variable name, so you can't store the result into it.

Did you mean string += ((t[1])/length) * t[1]? That would make more sense. Of course, you're still trying to add a number to a string, or multiply by a string... one of those t[1]s should probably be a t[0].

SVN Repository on Google Drive or DropBox

While possible, it's potentially very risky - if you attempt to commit changes to the repository from 2 different locations simultaneously, you'll get a giant mess due to the file conflicts. Get a free private SVN host somewhere, or set up a repository on a server you have access to.

Edit based on a recent experience: If you have files open that are managed by Dropbox and your computer crashes, your files may be truncated to 0 bytes. If this happens to the files which manage your repository, your repository will be corrupted. If you discover this soon enough, you can use Dropbox's "recover old version" feature but you're still taking a risk.

How to serialize SqlAlchemy result to JSON?

step1:
class CNAME:
   ...
   def as_dict(self):
       return {item.name: getattr(self, item.name) for item in self.__table__.columns}

step2:
list = []
for data in session.query(CNAME).all():
    list.append(data.as_dict())

step3:
return jsonify(list)

How to use LINQ to select object with minimum or maximum property value

Perfectly simple use of aggregate (equivalent to fold in other languages):

var firstBorn = People.Aggregate((min, x) => x.DateOfBirth < min.DateOfBirth ? x : min);

The only downside is that the property is accessed twice per sequence element, which might be expensive. That's hard to fix.

How to remove \n from a list element?

from this link:

you can use rstrip() method. Example

mystring = "hello\n"    
print(mystring.rstrip('\n'))

Running CMake on Windows

The default generator for Windows seems to be set to NMAKE. Try to use:

cmake -G "MinGW Makefiles"

Or use the GUI, and select MinGW Makefiles when prompted for a generator. Don't forget to cleanup the directory where you tried to run CMake, or delete the cache in the GUI. Otherwise, it will try again with NMAKE.

Window.open and pass parameters by post method

I created a function to generate a form, based on url, target and an object as the POST/GET data and submit method. It supports nested and mixed types within that object, so it can fully replicate any structure you feed it: PHP automatically parses it and returns it as a nested array. However, there is a single restriction: the brackets [ and ] must not be part of any key in the object (like {"this [key] is problematic" : "hello world"}). If someone knows how to escape it properly, please do tell!

Without further ado, here is the source:

_x000D_
_x000D_
function getForm(url, target, values, method) {_x000D_
  function grabValues(x) {_x000D_
    var path = [];_x000D_
    var depth = 0;_x000D_
    var results = [];_x000D_
_x000D_
    function iterate(x) {_x000D_
      switch (typeof x) {_x000D_
        case 'function':_x000D_
        case 'undefined':_x000D_
        case 'null':_x000D_
          break;_x000D_
        case 'object':_x000D_
          if (Array.isArray(x))_x000D_
            for (var i = 0; i < x.length; i++) {_x000D_
              path[depth++] = i;_x000D_
              iterate(x[i]);_x000D_
            }_x000D_
          else_x000D_
            for (var i in x) {_x000D_
              path[depth++] = i;_x000D_
              iterate(x[i]);_x000D_
            }_x000D_
          break;_x000D_
        default:_x000D_
          results.push({_x000D_
            path: path.slice(0),_x000D_
            value: x_x000D_
          })_x000D_
          break;_x000D_
      }_x000D_
      path.splice(--depth);_x000D_
    }_x000D_
    iterate(x);_x000D_
    return results;_x000D_
  }_x000D_
  var form = document.createElement("form");_x000D_
  form.method = method;_x000D_
  form.action = url;_x000D_
  form.target = target;_x000D_
_x000D_
  var values = grabValues(values);_x000D_
_x000D_
  for (var j = 0; j < values.length; j++) {_x000D_
    var input = document.createElement("input");_x000D_
    input.type = "hidden";_x000D_
    input.value = values[j].value;_x000D_
    input.name = values[j].path[0];_x000D_
    for (var k = 1; k < values[j].path.length; k++) {_x000D_
      input.name += "[" + values[j].path[k] + "]";_x000D_
    }_x000D_
    form.appendChild(input);_x000D_
  }_x000D_
  return form;_x000D_
}
_x000D_
_x000D_
_x000D_

Usage example:

_x000D_
_x000D_
document.body.onclick = function() {_x000D_
  var obj = {_x000D_
    "a": [1, 2, [3, 4]],_x000D_
    "b": "a",_x000D_
    "c": {_x000D_
      "x": [1],_x000D_
      "y": [2, 3],_x000D_
      "z": [{_x000D_
        "a": "Hello",_x000D_
        "b": "World"_x000D_
      }, {_x000D_
        "a": "Hallo",_x000D_
        "b": "Welt"_x000D_
      }]_x000D_
    }_x000D_
  };_x000D_
_x000D_
  var form = getForm("http://example.com", "_blank", obj, "post");_x000D_
_x000D_
  document.body.appendChild(form);_x000D_
  form.submit();_x000D_
  form.parentNode.removeChild(form);_x000D_
}
_x000D_
_x000D_
_x000D_

What's the maximum value for an int in PHP?

32-bit builds of PHP:

  • Integers can be from -2,147,483,648 to 2,147,483,647 (~ ± 2 billion)

64-bit builds of PHP:

  • Integers can be from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807 (~ ± 9 quintillion)

Numbers are inclusive.

Note: some 64-bit builds once used 32-bit integers, particularly older Windows builds of PHP

Values outside of these ranges are represented by floating point values, as are non-integer values within these ranges. The interpreter will automatically determine when this switch to floating point needs to happen based on whether the result value of a calculation can't be represented as an integer.

PHP has no support for "unsigned" integers as such, limiting the maximum value of all integers to the range of a "signed" integer.

How to use ng-repeat for dictionaries in AngularJs?

You can use

<li ng-repeat="(name, age) in items">{{name}}: {{age}}</li>

See ngRepeat documentation. Example: http://jsfiddle.net/WRtqV/1/

How do I get the Git commit count?

U can just use :

git shortlog -s -n

Result :

 827  user one
    15  user two
     2  Gest 

How do I get my page title to have an icon?

This code will defiantly work. In a comment I saw they are using ejs syntex that is not for everyone only for those who are working with express.js

<link rel="icon" href="demo_icon.gif" sizes="16x16">
<title> Reddit</title>

you can also add png and jpg

typedef fixed length array

The typedef would be

typedef char type24[3];

However, this is probably a very bad idea, because the resulting type is an array type, but users of it won't see that it's an array type. If used as a function argument, it will be passed by reference, not by value, and the sizeof for it will then be wrong.

A better solution would be

typedef struct type24 { char x[3]; } type24;

You probably also want to be using unsigned char instead of char, since the latter has implementation-defined signedness.

Wi-Fi Direct and iOS Support

It took me a while to find out what is going on, but here is the summary. I hope this save people a lot of time.

Apple are not playing nice with Wi-Fi Direct, not in the same way that Android is. The Multipeer Connectivity Framework that Apple provides combines both BLE and WiFi Direct together and will only work with Apple devices and not any device that is using Wi-Fi Direct.

https://developer.apple.com/library/ios/documentation/MultipeerConnectivity/Reference/MultipeerConnectivityFramework/index.html

It states the following in this documentation - "The Multipeer Connectivity framework provides support for discovering services provided by nearby iOS devices using infrastructure Wi-Fi networks, peer-to-peer Wi-Fi, and Bluetooth personal area networks and subsequently communicating with those services by sending message-based data, streaming data, and resources (such as files)."

Additionally, Wi-Fi direct in this mode between i-Devices will need iPhone 5 and above.

There are apps that use a form of Wi-Fi Direct on the App Store, but these are using their own libraries.

How can I know when an EditText loses focus?

Implement onFocusChange of setOnFocusChangeListener and there's a boolean parameter for hasFocus. When this is false, you've lost focus to another control.

 EditText txtEdit = (EditText) findViewById(R.id.edittxt);

 txtEdit.setOnFocusChangeListener(new OnFocusChangeListener() {          
        @Override
        public void onFocusChange(View v, boolean hasFocus) {
            if (!hasFocus) {
               // code to execute when EditText loses focus
            }
        }
    });

How to find all positions of the maximum value in a list?

Just one line:

idx = max(range(len(a)), key = lambda i: a[i])

How to get package name from anywhere?

Create a java module to be initially run when starting your app. This module would be extending the android Application class and would initialize any global app variables and also contain app-wide utility routines -

public class MyApplicationName extends Application {

    private final String PACKAGE_NAME = "com.mysite.myAppPackageName";

    public String getPackageName() { return PACKAGE_NAME; }
}

Of course, this could include logic to obtain the package name from the android system; however, the above is smaller, faster and cleaner code than obtaining it from android.

Be sure to place an entry in your AndroidManifest.xml file to tell android to run your application module before running any activities -

<application 
    android:name=".MyApplicationName" 
    ...
>

Then, to obtain the package name from any other module, enter

MyApp myApp = (MyApp) getApplicationContext();
String myPackage = myApp.getPackageName();

Using an application module also gives you a context for modules that need but don't have a context.

Brew install docker does not include docker engine?

The following steps work fine on macOS Sierra 10.12.4. Note that after brew installs Docker, the docker command (symbolic link) is not available at /usr/local/bin. Running the Docker app for the first time creates this symbolic link. See the detailed steps below.

  1. Install Docker.

    brew cask install docker
    
  2. Launch Docker.

    • Press ? + Space to bring up Spotlight Search and enter Docker to launch Docker.
    • In the Docker needs privileged access dialog box, click OK.
    • Enter password and click OK.

    When Docker is launched in this manner, a Docker whale icon appears in the status menu. As soon as the whale icon appears, the symbolic links for docker, docker-compose, docker-credential-osxkeychain and docker-machine are created in /usr/local/bin.

    $ ls -l /usr/local/bin/docker*
    lrwxr-xr-x  1 susam  domain Users  67 Apr 12 14:14 /usr/local/bin/docker -> /Users/susam/Library/Group Containers/group.com.docker/bin/docker
    lrwxr-xr-x  1 susam  domain Users  75 Apr 12 14:14 /usr/local/bin/docker-compose -> /Users/susam/Library/Group Containers/group.com.docker/bin/docker-compose
    lrwxr-xr-x  1 susam  domain Users  90 Apr 12 14:14 /usr/local/bin/docker-credential-osxkeychain -> /Users/susam/Library/Group Containers/group.com.docker/bin/docker-credential-osxkeychain
    lrwxr-xr-x  1 susam  domain Users  75 Apr 12 14:14 /usr/local/bin/docker-machine -> /Users/susam/Library/Group Containers/group.com.docker/bin/docker-machine
    
  3. Click on the docker whale icon in the status menu and wait for it to show Docker is running.

    enter image description here enter image description here

  4. Test that docker works fine.

    $ docker run hello-world
    Unable to find image 'hello-world:latest' locally
    latest: Pulling from library/hello-world
    78445dd45222: Pull complete
    Digest: sha256:c5515758d4c5e1e838e9cd307f6c6a0d620b5e07e6f927b07d05f6d12a1ac8d7
    Status: Downloaded newer image for hello-world:latest
    
    Hello from Docker!
    This message shows that your installation appears to be working correctly.
    
    To generate this message, Docker took the following steps:
     1. The Docker client contacted the Docker daemon.
     2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
     3. The Docker daemon created a new container from that image which runs the
        executable that produces the output you are currently reading.
     4. The Docker daemon streamed that output to the Docker client, which sent it
        to your terminal.
    
    To try something more ambitious, you can run an Ubuntu container with:
     $ docker run -it ubuntu bash
    
    Share images, automate workflows, and more with a free Docker ID:
     https://cloud.docker.com/
    
    For more examples and ideas, visit:
     https://docs.docker.com/engine/userguide/
    
    $ docker version
    Client:
     Version:      17.03.1-ce
     API version:  1.27
     Go version:   go1.7.5
     Git commit:   c6d412e
     Built:        Tue Mar 28 00:40:02 2017
     OS/Arch:      darwin/amd64
    
    Server:
     Version:      17.03.1-ce
     API version:  1.27 (minimum version 1.12)
     Go version:   go1.7.5
     Git commit:   c6d412e
     Built:        Fri Mar 24 00:00:50 2017
     OS/Arch:      linux/amd64
     Experimental: true
    
  5. If you are going to use docker-machine to create virtual machines, install VirtualBox.

    brew cask install virtualbox
    

    Note that if VirtualBox is not installed, then docker-machine fails with the following error.

    $ docker-machine create manager
    Running pre-create checks...
    Error with pre-create check: "VBoxManage not found. Make sure VirtualBox is installed and VBoxManage is in the path"
    

Babel 6 regeneratorRuntime is not defined

In 2019 with Babel 7.4.0+, babel-polyfill package has been deprecated in favor of directly including core-js/stable (core-js@3+, to polyfill ECMAScript features) and regenerator-runtime/runtime (needed to use transpiled generator functions):

import "core-js/stable";
import "regenerator-runtime/runtime";

Information from babel-polyfill documentation.

EC2 Instance Cloning

To Answer your question: now AWS make cloning real easy see Launch instance from your Existing Instance

  1. On the EC2 Instances page, select the instance you want to use
  2. Choose Actions, and then Launch More Like This.
  3. Review & Launch

This will take the existing instance as a Template for the new once.

or you can also take a snapshot of the existing volume and use the snapshot with the AMI (existing one) which you ping during your instance launch

Move top 1000 lines from text file to a new file using Unix shell commands

head -1000 file.txt > first100lines.txt
tail --lines=+1001 file.txt > restoffile.txt

Check if a key is down?

I don't believe there is anything like an isKeyDown function, but you could write your own.

Basically, create an array whose length is the number of keys you want to monitor. Then using the documents/pages/controls keyUp and keyDown events, update the array with that key's state.

Then write a function that checks if a certain key is down and returns a bool.

var keyEnum = { W_Key:0, A_Key:1, S_Key:2, D_Key:3 };
var keyArray = new Array(4);

function onKeyDown()
{
    // Detect which key was pressed
    if( key == 'w' )
        keyArray[keyEnum.W_Key] = true;
    // Repeat for each key you care about...
}

function onKeyUp()
{
    // Detect which key was released
    if( key == 'w' )
        keyArray[keyEnum.W_Key] = false;
    // Repeat for each key you care about...
}

function isKeyDown(key)
{
    return keyArray[key];
}

That should accomplish what you want.

How to format a java.sql.Timestamp(yyyy-MM-dd HH:mm:ss.S) to a date(yyyy-MM-dd HH:mm:ss)

You do not need to use substring at all since your format doesn't hold that info.

SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String fechaStr = "2013-10-10 10:49:29.10000";  
Date fechaNueva = format.parse(fechaStr);

System.out.println(format.format(fechaNueva)); // Prints 2013-10-10 10:49:29

How to tell if node.js is installed or not

Open a terminal window. Type:

node -v

This will display your nodejs version.

Navigate to where you saved your script and input:

node script.js

This will run your script.

Right way to write JSON deserializer in Spring or extend it

With Spring MVC 4.2.1.RELEASE, you need to use the new Jackson2 dependencies as below for the Deserializer to work.

Dont use this

<dependency>  
            <groupId>org.codehaus.jackson</groupId>  
            <artifactId>jackson-mapper-asl</artifactId>  
            <version>1.9.12</version>  
        </dependency>  

Use this instead.

<dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.2.2</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.2.2</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.2.2</version>
        </dependency>  

Also use com.fasterxml.jackson.databind.JsonDeserializer and com.fasterxml.jackson.databind.annotation.JsonDeserialize for the deserialization and not the classes from org.codehaus.jackson

Intellij reformat on file save

I thought there was something like that in IntelliJ, but I can't find it. The only clean-up that happens at save is that white space at the ends of lines is removed. I thought I had to specify that behavior at one point, but I don't see anything related at this point.

How to set index.html as root file in Nginx?

in your location block you can do:

location / {
  try_files $uri $uri/index.html;
}

which will tell ngingx to look for a file with the exact name given first, and if none such file is found it will try uri/index.html. So if a request for https://www.example.com/ comes it it would look for an exact file match first, and not finding that would then check for index.html

How to find row number of a value in R code

(1:nrow(mydata_2))[mydata_2[,4] == 1578]

Of course there may be more than one row with a value of 1578.

How to set image width to be 100% and height to be auto in react native?

this may help for auto adjusting the image height having image 100% width

image: { width: "100%", resizeMode: "center" "contain", height: undefined, aspectRatio: 1, }

Find and copy files

i faced an issue something like this...

Actually, in two ways you can process find command output in copy command

  1. If find command's output doesn't contain any space i.e if file name doesn't contain space in it then you can use below mentioned command:

    Syntax: find <Path> <Conditions> | xargs cp -t <copy file path>

    Example: find -mtime -1 -type f | xargs cp -t inner/

  2. But most of the time our production data files might contain space in it. So most of time below mentioned command is safer:

    Syntax: find <path> <condition> -exec cp '{}' <copy path> \;

    Example find -mtime -1 -type f -exec cp '{}' inner/ \;

In the second example, last part i.e semi-colon is also considered as part of find command, that should be escaped before press the enter button. Otherwise you will get an error something like this

find: missing argument to `-exec'

In your case, copy command syntax is wrong in order to copy find file into /home/shantanu/tosend. The following command will work:

find /home/shantanu/processed/ -name '*2011*.xml' -exec cp  {} /home/shantanu/tosend \;

apache server reached MaxClients setting, consider raising the MaxClients setting

Did you consider using nginx (or other event based web server) instead of apache?

nginx shall allow higher number of connections and consume much less resources (as it is event based and does not create separate process per connection). Anyway, you will need some processes, doing real work (like WSGI servers or so) and if they stay on the same server as the front end web server, you only shift the performance problem to a bit different place.

Latest apache version shall allow similar solution (configure it in event based manner), but this is not my area of expertise.

angular2: how to copy object into another object

As suggested before, the clean way of deep copying objects having nested objects inside is by using lodash's cloneDeep method.

For Angular, you can do it like this:

Install lodash with yarn add lodash or npm install lodash.

In your component, import cloneDeep and use it:

import * as cloneDeep from 'lodash/cloneDeep';
...
clonedObject = cloneDeep(originalObject);

It's only 18kb added to your build, well worth for the benefits.

I've also written an article here, if you need more insight on why using lodash's cloneDeep.

How can I show an element that has display: none in a CSS rule?

I can see that you want to write you own short javascript for this, but have you considered to use Frameworks for HTML manipulation instead? jQuery is my prefered tool for such a task, eventhough its an overkill for your current question as it has SO many extra functionalities.

Have a look at jQuery here

How to generate random positive and negative numbers in Java

This is an old question I know but um....

n=n-(n*2)

socket programming multiple client to one server

This is the echo server handling multiple clients... Runs fine and good using Threads

// echo server
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;


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


    Socket s=null;
    ServerSocket ss2=null;
    System.out.println("Server Listening......");
    try{
        ss2 = new ServerSocket(4445); // can also use static final PORT_NUM , when defined

    }
    catch(IOException e){
    e.printStackTrace();
    System.out.println("Server error");

    }

    while(true){
        try{
            s= ss2.accept();
            System.out.println("connection Established");
            ServerThread st=new ServerThread(s);
            st.start();

        }

    catch(Exception e){
        e.printStackTrace();
        System.out.println("Connection Error");

    }
    }

}

}

class ServerThread extends Thread{  

    String line=null;
    BufferedReader  is = null;
    PrintWriter os=null;
    Socket s=null;

    public ServerThread(Socket s){
        this.s=s;
    }

    public void run() {
    try{
        is= new BufferedReader(new InputStreamReader(s.getInputStream()));
        os=new PrintWriter(s.getOutputStream());

    }catch(IOException e){
        System.out.println("IO error in server thread");
    }

    try {
        line=is.readLine();
        while(line.compareTo("QUIT")!=0){

            os.println(line);
            os.flush();
            System.out.println("Response to Client  :  "+line);
            line=is.readLine();
        }   
    } catch (IOException e) {

        line=this.getName(); //reused String line for getting thread name
        System.out.println("IO Error/ Client "+line+" terminated abruptly");
    }
    catch(NullPointerException e){
        line=this.getName(); //reused String line for getting thread name
        System.out.println("Client "+line+" Closed");
    }

    finally{    
    try{
        System.out.println("Connection Closing..");
        if (is!=null){
            is.close(); 
            System.out.println(" Socket Input Stream Closed");
        }

        if(os!=null){
            os.close();
            System.out.println("Socket Out Closed");
        }
        if (s!=null){
        s.close();
        System.out.println("Socket Closed");
        }

        }
    catch(IOException ie){
        System.out.println("Socket Close Error");
    }
    }//end finally
    }
}

Also here is the code for the client.. Just execute this code for as many times as you want to create multiple client..

// A simple Client Server Protocol .. Client for Echo Server

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.Socket;

public class NetworkClient {

public static void main(String args[]) throws IOException{


    InetAddress address=InetAddress.getLocalHost();
    Socket s1=null;
    String line=null;
    BufferedReader br=null;
    BufferedReader is=null;
    PrintWriter os=null;

    try {
        s1=new Socket(address, 4445); // You can use static final constant PORT_NUM
        br= new BufferedReader(new InputStreamReader(System.in));
        is=new BufferedReader(new InputStreamReader(s1.getInputStream()));
        os= new PrintWriter(s1.getOutputStream());
    }
    catch (IOException e){
        e.printStackTrace();
        System.err.print("IO Exception");
    }

    System.out.println("Client Address : "+address);
    System.out.println("Enter Data to echo Server ( Enter QUIT to end):");

    String response=null;
    try{
        line=br.readLine(); 
        while(line.compareTo("QUIT")!=0){
                os.println(line);
                os.flush();
                response=is.readLine();
                System.out.println("Server Response : "+response);
                line=br.readLine();

            }



    }
    catch(IOException e){
        e.printStackTrace();
    System.out.println("Socket read Error");
    }
    finally{

        is.close();os.close();br.close();s1.close();
                System.out.println("Connection Closed");

    }

}
}

Safest way to get last record ID from a table

SELECT IDENT_CURRENT('Table')

You can use one of these examples:

SELECT * FROM Table 
WHERE ID = (
    SELECT IDENT_CURRENT('Table'))

SELECT * FROM Table
WHERE ID = (
    SELECT MAX(ID) FROM Table)

SELECT TOP 1 * FROM Table
ORDER BY ID DESC

But the first one will be more efficient because no index scan is needed (if you have index on Id column).

The second one solution is equivalent to the third (both of them need to scan table to get max id).

What is the difference between __dirname and ./ in node.js?

The gist

In Node.js, __dirname is always the directory in which the currently executing script resides (see this). So if you typed __dirname into /d1/d2/myscript.js, the value would be /d1/d2.

By contrast, . gives you the directory from which you ran the node command in your terminal window (i.e. your working directory) when you use libraries like path and fs. Technically, it starts out as your working directory but can be changed using process.chdir().

The exception is when you use . with require(). The path inside require is always relative to the file containing the call to require.

For example...

Let's say your directory structure is

/dir1
  /dir2
    pathtest.js

and pathtest.js contains

var path = require("path");
console.log(". = %s", path.resolve("."));
console.log("__dirname = %s", path.resolve(__dirname));

and you do

cd /dir1/dir2
node pathtest.js

you get

. = /dir1/dir2
__dirname = /dir1/dir2

Your working directory is /dir1/dir2 so that's what . resolves to. Since pathtest.js is located in /dir1/dir2 that's what __dirname resolves to as well.

However, if you run the script from /dir1

cd /dir1
node dir2/pathtest.js

you get

. = /dir1
__dirname = /dir1/dir2

In that case, your working directory was /dir1 so that's what . resolved to, but __dirname still resolves to /dir1/dir2.

Using . inside require...

If inside dir2/pathtest.js you have a require call into include a file inside dir1 you would always do

require('../thefile')

because the path inside require is always relative to the file in which you are calling it. It has nothing to do with your working directory.

Google Play on Android 4.0 emulator

Have you ever tried Genymotion? I've read about it last week and it is great. They have several Android Images that you run (with their own software). The images are INCREDIBLY fast and they have Google Play installed on them. Check it out if it is the kind of thing that you need.

http://www.genymotion.com/

CMake error at CMakeLists.txt:30 (project): No CMAKE_C_COMPILER could be found

This happened to me after I installed Visual Studio 15 2017.

The C++ compiler for Visual Studio 14 2015 was not the problem. It seemed to be a problem with the Windows 10 SDK.

Adding the Windows 10 SDKs to Visual Studio 14 2015 solved the problem for me.

See attached screenshot.

Enter image description here

Passing a variable from one php include file to another: global vs. not

This is all you have to do:

In front.inc

global $name;
$name = 'james';

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

Get the XML using Ajax call, find the main element, loop through all the element and append data in table.

Sample code

 //ajax call to load XML and parse it
        $.ajax({
            type: 'GET',
            url: 'https://res.cloudinary.com/dmsxwwfb5/raw/upload/v1591716537/book.xml',           // The file path.
            dataType: 'xml',    
            success: function(xml) {
               //find all book tags, loop them and append to table body
                $(xml).find('book').each(function() {
                    
                    // Append new data to the tbody element.
                    $('#tableBody').append(
                        '<tr>' +
                            '<td>' +
                                $(this).find('author').text() + '</td> ' +
                            '<td>' +
                                $(this).find('title').text() + '</td> ' +
                            '<td>' +
                                $(this).find('genre').text() + '</td> ' +
                                '<td>' +
                                $(this).find('price').text() + '</td> ' +
                                '<td>' +
                                $(this).find('description').text() + '</td> ' +
                        '</tr>');
                });
            }
        });

Fiddle link: https://jsfiddle.net/pn9xs8hf/2/

Source: Read XML using jQuery & load it in HTML Table

Disable html5 video autoplay

I'd remove the autoplay attribute, since if the browser encounters it, it autoplays!

autoplay is a HTML boolean attribute, but be aware that the values true and false are not allowed. To represent a false value, you must omit the attribute.

The values "true" and "false" are not allowed on boolean attributes. To represent a false value, the attribute has to be omitted altogether.

Also, the type goes inside the source, like this:

<video width="640" height="480" controls preload="none">
   <source src="http://example.com/mytestfile.mp4" type="video/mp4">
   Your browser does not support the video tag.
</video>

References:

Using subprocess to run Python script on Windows

You are using a pathname separator which is platform dependent. Windows uses "\" and Unix uses "/".

Convert to/from DateTime and Time in Ruby

While making such conversions one should take into consideration the behavior of timezones while converting from one object to the other. I found some good notes and examples in this stackoverflow post.

Typescript: How to define type for a function callback (as any function type, not universal any) used in a method parameter

Following from Ryan's answer, I think that the interface you are looking for is defined as follows:

interface Param {
    title: string;
    callback: () => void;
}

How the single threaded non blocking IO model works in Node.js

Node.js is based on the event loop programming model. The event loop runs in single thread and repeatedly waits for events and then runs any event handlers subscribed to those events. Events can be for example

  • timer wait is complete
  • next chunk of data is ready to be written to this file
  • theres a fresh new HTTP request coming our way

All of this runs in single thread and no JavaScript code is ever executed in parallel. As long as these event handlers are small and wait for yet more events themselves everything works out nicely. This allows multiple request to be handled concurrently by a single Node.js process.

(There's a little bit magic under the hood as where the events originate. Some of it involve low level worker threads running in parallel.)

In this SQL case, there's a lot of things (events) happening between making the database query and getting its results in the callback. During that time the event loop keeps pumping life into the application and advancing other requests one tiny event at a time. Therefore multiple requests are being served concurrently.

event loop high level view

According to: "Event loop from 10,000ft - core concept behind Node.js".

Deploying website: 500 - Internal server error

In addition to the other suggestions, make sure to change the existingResponse attribute of the httpErrors node to Auto from Replace, or to remove that property entirely.

<httpErrors existingResponse="Replace" />
                              ^^^^^^^ not going to work with this here

How to set the component size with GridLayout? Is there a better way?

Don't use GridLayout for something it wasn't meant to do. It sounds to me like GridBagLayout would be a better fit for you, either that or MigLayout (though you'll have to download that first since it's not part of standard Java). Either that or combine layout managers such as BoxLayout for the lines and GridLayout to hold all the rows.

For example, using GridBagLayout:

import java.awt.*;
import javax.swing.*;

public class LayoutEg1 extends JPanel{
    private static final int ROWS = 10;

    public LayoutEg1() {
        setLayout(new GridBagLayout());
        for (int i = 0; i < ROWS; i++) {
            GridBagConstraints gbc = makeGbc(0, i);
            JLabel label = new JLabel("Row Label " + (i + 1));
            add(label, gbc);

            JPanel panel = new JPanel();
            panel.add(new JCheckBox("check box"));
            panel.add(new JTextField(10));
            panel.add(new JButton("Button"));
            panel.setBorder(BorderFactory.createEtchedBorder());
            gbc = makeGbc(1, i);
            add(panel, gbc);
        }
    }

    private GridBagConstraints makeGbc(int x, int y) {
        GridBagConstraints gbc = new GridBagConstraints();
        gbc.gridwidth = 1;
        gbc.gridheight = 1;
        gbc.gridx = x;
        gbc.gridy = y;
        gbc.weightx = x;
        gbc.weighty = 1.0;
        gbc.insets = new Insets(5, 5, 5, 5);
        gbc.anchor = (x == 0) ? GridBagConstraints.LINE_START : GridBagConstraints.LINE_END;
        gbc.fill = GridBagConstraints.HORIZONTAL;
        return gbc;
    }

    private static void createAndShowUI() {
        JFrame frame = new JFrame("Layout Eg1");
        frame.getContentPane().add(new LayoutEg1());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                createAndShowUI();
            }
        });
    }
}

Get a random boolean in python?

I was curious as to how the speed of the numpy answer performed against the other answers since this was left out of the comparisons. To generate one random bool this is much slower but if you wanted to generate many then this becomes much faster:

$ python -m timeit -s "from random import random" "random() < 0.5"
10000000 loops, best of 3: 0.0906 usec per loop
$ python -m timeit -s "import numpy as np" "np.random.randint(2, size=1)"
100000 loops, best of 3: 4.65 usec per loop

$ python -m timeit -s "from random import random" "test = [random() < 0.5 for i in range(1000000)]"
10 loops, best of 3: 118 msec per loop
$ python -m timeit -s "import numpy as np" "test = np.random.randint(2, size=1000000)"
100 loops, best of 3: 6.31 msec per loop

JavaScript before leaving the page

You can use the following one-liner to always ask the user before leaving the page.

window.onbeforeunload = s => "";

To ask the user when something on the page has been modified, see this answer.

How to start Fragment from an Activity

You can either add or replace fragment in your activity. Create a FrameLayout in activity layout xml file.

Then do this in your activity to add fragment:

FragmentManager manager = getFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
transaction.add(R.id.container,YOUR_FRAGMENT_NAME,YOUR_FRAGMENT_STRING_TAG);
transaction.addToBackStack(null);
transaction.commit();

And to replace fragment do this:

FragmentManager manager = getFragmentManager();
FragmentTransaction transaction = manager.beginTransaction();
transaction.replace(R.id.container,YOUR_FRAGMENT_NAME,YOUR_FRAGMENT_STRING_TAG);
transaction.addToBackStack(null);
transaction.commit();

See Android documentation on adding a fragment to an activity or following related questions on SO:

Difference between add(), replace(), and addToBackStack()

Basic difference between add() and replace() method of Fragment

Difference between add() & replace() with Fragment's lifecycle

How to watch and reload ts-node when TypeScript files change

I would prefer to not use ts-node and always run from dist folder.

To do that, just setup your package.json with default config:

....
"main": "dist/server.js",
  "scripts": {
    "build": "tsc",
    "prestart": "npm run build",
    "start": "node .",
    "dev": "nodemon"
  },
....

and then add nodemon.json config file:

{
  "watch": ["src"],
  "ext": "ts",
  "ignore": ["src/**/*.spec.ts"],
  "exec": "npm restart"
}

Here, i use "exec": "npm restart"
so all ts file will re-compile to js file and then restart the server.

To run while in dev environment,

npm run dev

Using this setup I will always run from the distributed files and no need for ts-node.

VBA macro that search for file in multiple subfolders

I actually just found this today for something I'm working on. This will return file paths for all files in a folder and its subfolders.

Dim colFiles As New Collection
RecursiveDir colFiles, "C:\Users\Marek\Desktop\Makro\", "*.*", True
Dim vFile As Variant

For Each vFile In colFiles
     'file operation here or store file name/path in a string array for use later in the script
     filepath(n) = vFile
     filename = fso.GetFileName(vFile) 'If you want the filename without full path
     n=n+1
Next vFile


'These two functions are required
Public Function RecursiveDir(colFiles As Collection, strFolder As String, strFileSpec As String, bIncludeSubfolders As Boolean)
Dim strTemp As String
Dim colFolders As New Collection
Dim vFolderName As Variant
strFolder = TrailingSlash(strFolder)
strTemp = Dir(strFolder & strFileSpec)
Do While strTemp <> vbNullString
    colFiles.Add strFolder & strTemp
    strTemp = Dir
Loop
If bIncludeSubfolders Then

    strTemp = Dir(strFolder, vbDirectory)
    Do While strTemp <> vbNullString
        If (strTemp <> ".") And (strTemp <> "..") Then
            If (GetAttr(strFolder & strTemp) And vbDirectory) <> 0 Then
                colFolders.Add strTemp
            End If
        End If
        strTemp = Dir
    Loop
    'Call RecursiveDir for each subfolder in colFolders
    For Each vFolderName In colFolders
        Call RecursiveDir(colFiles, strFolder & vFolderName, strFileSpec, True)
    Next vFolderName
End If
End Function

Public Function TrailingSlash(strFolder As String) As String
If Len(strFolder) > 0 Then
    If Right(strFolder, 1) = "\" Then
        TrailingSlash = strFolder
    Else
        TrailingSlash = strFolder & "\"
    End If
End If
End Function

This is adapted from a post by Ammara Digital Image Solutions.(http://www.ammara.com/access_image_faq/recursive_folder_search.html).

How to delete all rows from all tables in a SQL Server database?

In my case, I needed to set QUOTED_IDENTIFIER on. This led to a slight modification of Mark Rendle's answer above:

EXEC sp_MSForEachTable 'DISABLE TRIGGER ALL ON ?'
GO
EXEC sp_MSForEachTable 'ALTER TABLE ? NOCHECK CONSTRAINT ALL'
GO
EXEC sp_MSForEachTable 'SET QUOTED_IDENTIFIER ON; DELETE FROM ?'
GO
EXEC sp_MSForEachTable 'ALTER TABLE ? CHECK CONSTRAINT ALL'
GO
EXEC sp_MSForEachTable 'ENABLE TRIGGER ALL ON ?'
GO

Failed to decode downloaded font

for me it was a problem with lfs files that were not downloaded

git lfs fetch --all

fixed the problem.

see https://github.com/git-lfs/git-lfs/issues/325

How to create dispatch queue in Swift 3

Update for swift 5

Serial Queue

let serialQueue = DispatchQueue.init(label: "serialQueue")
serialQueue.async {
    // code to execute
}

Concurrent Queue

let concurrentQueue = DispatchQueue.init(label: "concurrentQueue", qos: .background, attributes: .concurrent, autoreleaseFrequency: .inherit, target: nil)

concurrentQueue.async {
// code to execute
}

From Apple documentation:

Parameters

label

A string label to attach to the queue to uniquely identify it in debugging tools such as Instruments, sample, stackshots, and crash reports. Because applications, libraries, and frameworks can all create their own dispatch queues, a reverse-DNS naming style (com.example.myqueue) is recommended. This parameter is optional and can be NULL.

qos

The quality-of-service level to associate with the queue. This value determines the priority at which the system schedules tasks for execution. For a list of possible values, see DispatchQoS.QoSClass.

attributes

The attributes to associate with the queue. Include the concurrent attribute to create a dispatch queue that executes tasks concurrently. If you omit that attribute, the dispatch queue executes tasks serially.

autoreleaseFrequency

The frequency with which to autorelease objects created by the blocks that the queue schedules. For a list of possible values, see DispatchQueue.AutoreleaseFrequency.

target

The target queue on which to execute blocks. Specify DISPATCH_TARGET_QUEUE_DEFAULT if you want the system to provide a queue that is appropriate for the current object.

How to use QueryPerformanceCounter?

#include <windows.h>

double PCFreq = 0.0;
__int64 CounterStart = 0;

void StartCounter()
{
    LARGE_INTEGER li;
    if(!QueryPerformanceFrequency(&li))
    cout << "QueryPerformanceFrequency failed!\n";

    PCFreq = double(li.QuadPart)/1000.0;

    QueryPerformanceCounter(&li);
    CounterStart = li.QuadPart;
}
double GetCounter()
{
    LARGE_INTEGER li;
    QueryPerformanceCounter(&li);
    return double(li.QuadPart-CounterStart)/PCFreq;
}

int main()
{
    StartCounter();
    Sleep(1000);
    cout << GetCounter() <<"\n";
    return 0;
}

This program should output a number close to 1000 (windows sleep isn't that accurate, but it should be like 999).

The StartCounter() function records the number of ticks the performance counter has in the CounterStart variable. The GetCounter() function returns the number of milliseconds since StartCounter() was last called as a double, so if GetCounter() returns 0.001 then it has been about 1 microsecond since StartCounter() was called.

If you want to have the timer use seconds instead then change

PCFreq = double(li.QuadPart)/1000.0;

to

PCFreq = double(li.QuadPart);

or if you want microseconds then use

PCFreq = double(li.QuadPart)/1000000.0;

But really it's about convenience since it returns a double.

How to map and remove nil values in Ruby

Definitely compact is the best approach for solving this task. However, we can achieve the same result just with a simple subtraction:

[1, nil, 3, nil, nil] - [nil]
 => [1, 3]

Can't build create-react-app project with custom PUBLIC_URL

That is not how the PUBLIC_URL variable is used. According to the documentation, you can use the PUBLIC_URL in your HTML:

<link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico">

Or in your JavaScript:

render() {
  // Note: this is an escape hatch and should be used sparingly!
  // Normally we recommend using `import` for getting asset URLs
  // as described in “Adding Images and Fonts” above this section.
  return <img src={process.env.PUBLIC_URL + '/img/logo.png'} />;
}

The PUBLIC_URL is not something you set to a value of your choosing, it is a way to store files in your deployment outside of Webpack's build system.

To view this, run your CRA app and add this to the src/index.js file:

console.log('public url: ', process.env.PUBLIC_URL)

You'll see the URL already exists.

Read more in the CRA docs.

'list' object has no attribute 'shape'

list object in python does not have 'shape' attribute because 'shape' implies that all the columns (or rows) have equal length along certain dimension.

Let's say list variable a has following properties: a = [[2, 3, 4] [0, 1] [87, 8, 1]]

it is impossible to define 'shape' for variable 'a'. That is why 'shape' might be determined only with 'arrays' e.g.

b = numpy.array([[2, 3, 4]
                [0, 1, 22]
                [87, 8, 1]])

I hope this explanation clarifies well this question.

Load external css file like scripts in jquery which is compatible in ie also

Quick function based on responses.

loadCSS = function(href) {

  var cssLink = $("<link>");
  $("head").append(cssLink); //IE hack: append before setting href

  cssLink.attr({
    rel:  "stylesheet",
    type: "text/css",
    href: href
  });

};

Usage:

loadCSS("/css/file.css");

What causes the Broken Pipe Error?

The current state of a socket is determined by 'keep-alive' activity. In your case, this is possible that when you are issuing the send call, the keep-alive activity tells that the socket is active and so the send call will write the required data (40 bytes) in to the buffer and returns without giving any error.

When you are sending a bigger chunk, the send call goes in to blocking state.

The send man page also confirms this:

When the message does not fit into the send buffer of the socket, send() normally blocks, unless the socket has been placed in non-blocking I/O mode. In non-blocking mode it would return EAGAIN in this case

So, while blocking for the free available buffer, if the caller is notified (by keep-alive mechanism) that the other end is no more present, the send call will fail.

Predicting the exact scenario is difficult with the mentioned info, but I believe, this should be the reason for you problem.

Is it valid to have a html form inside another html form?

rather use a custom javascript-method inside the action attribute of the form!

eg

<html>
    <head>
        <script language="javascript" type="text/javascript">
        var input1 = null;
        var input2 = null;
        function InitInputs() {
            if (input1 == null) {
                input1 = document.getElementById("input1");
            }
            if (input2 == null) {
                input2 = document.getElementById("input2");
            }

            if (input1 == null) {
                alert("input1 missing");
            }
            if (input2 == null) {
                alert("input2 missing");
            }
        }
        function myMethod1() {
            InitInputs();
            alert(input1.value + " " + input2.value);
        }
        function myMethod2() {
            InitInputs();
            alert(input1.value);
        }
        </script>
    </head>
    <body>
        <form action="javascript:myMethod1();">
            <input id="input1" type="text" />
            <input id="input2" type="text" />
            <input type="button" onclick="myMethod2()" value="myMethod2"/>
            <input type="submit" value="myMethod1" />
        </form>
    </body>
</html>

Counting unique / distinct values by group in a data frame

In dplyr you may use n_distinct to "count the number of unique values":

library(dplyr)
myvec %>%
  group_by(name) %>%
  summarise(n_distinct(order_no))

Change line width of lines in matplotlib pyplot legend

@ImportanceOfBeingErnest 's answer is good if you only want to change the linewidth inside the legend box. But I think it is a bit more complex since you have to copy the handles before changing legend linewidth. Besides, it can not change the legend label fontsize. The following two methods can not only change the linewidth but also the legend label text font size in a more concise way.

Method 1

import numpy as np
import matplotlib.pyplot as plt

# make some data
x = np.linspace(0, 2*np.pi)

y1 = np.sin(x)
y2 = np.cos(x)

# plot sin(x) and cos(x)
fig = plt.figure()
ax  = fig.add_subplot(111)
ax.plot(x, y1, c='b', label='y1')
ax.plot(x, y2, c='r', label='y2')

leg = plt.legend()
# get the individual lines inside legend and set line width
for line in leg.get_lines():
    line.set_linewidth(4)
# get label texts inside legend and set font size
for text in leg.get_texts():
    text.set_fontsize('x-large')

plt.savefig('leg_example')
plt.show()

Method 2

import numpy as np
import matplotlib.pyplot as plt

# make some data
x = np.linspace(0, 2*np.pi)

y1 = np.sin(x)
y2 = np.cos(x)

# plot sin(x) and cos(x)
fig = plt.figure()
ax  = fig.add_subplot(111)
ax.plot(x, y1, c='b', label='y1')
ax.plot(x, y2, c='r', label='y2')

leg = plt.legend()
# get the lines and texts inside legend box
leg_lines = leg.get_lines()
leg_texts = leg.get_texts()
# bulk-set the properties of all lines and texts
plt.setp(leg_lines, linewidth=4)
plt.setp(leg_texts, fontsize='x-large')
plt.savefig('leg_example')
plt.show()

The above two methods produce the same output image:

output image

HttpServletRequest - how to obtain the referring URL?

It's available in the HTTP referer header. You can get it in a servlet as follows:

String referrer = request.getHeader("referer"); // Yes, with the legendary misspelling.

You, however, need to realize that this is a client-controlled value and can thus be spoofed to something entirely different or even removed. Thus, whatever value it returns, you should not use it for any critical business processes in the backend, but only for presentation control (e.g. hiding/showing/changing certain pure layout parts) and/or statistics.

For the interested, background about the misspelling can be found in Wikipedia.

Ordering issue with date values when creating pivot tables

I saw this somewhere else. I am using 2016 Excel. What worked for me was to use YYYY Quarters (I was looking for quarterly data). So, I had the source data sorted as YYYY xQ. 2016 1Q, 2016 2Q, 2016 3Q, 2016, 4Q, 2017 1Q, 2017 2Q... You get the idea.

"Conversion to Dalvik format failed with error 1" on external JAR

In my case the problem is actually with OpenFeint API project. I have added OpenFeint as library project:

library project]![1]![Enter image description here.

It is also added into build path, ADT tools 16 gives error with this sceneario.

Right click on your project and click build path, configure the build path and then see the image and remove your project OpenFeint from here and all is done :)

Enter image description here

Clicking a button within a form causes page refresh

I also had the same problem, but gladelly I fixed this by changing the type like from type="submit" to type="button" and it worked.

How to get the last characters in a String in Java, regardless of String size

StringUtils.substringAfterLast("abcd: efg: 1006746", ": ") = "1006746";

As long as the format of the string is fixed you can use substringAfterLast.

How can I execute Shell script in Jenkinsfile?

There's the Managed Script Plugin which provides an easy way of managing user scripts. It also adds a build step action which allows you to select which user script to execute.

HRESULT: 0x80131040: The located assembly's manifest definition does not match the assembly reference

I ran into this issue in a web api project.

Api project was using a nuget package of a library with version 3. And one of the referenced assemblies say X was using older version of the same nuget package with version 2.

Whenever referenced assembly is built or any other project referencing X is rebuilt, api project's assemblies gets updated with lower version. And got this assembly reference error.

Rebuild works but in my case I wanted a long term solution.

I made the assemblies reference same version of nuget package.

How do I split an int into its digits?

Declare an Array and store Individual digits to the array like this

int num, temp, digits = 0, s, td=1;
int d[10];
cout << "Enter the Number: ";
cin >> num;
temp = num;
do{
    ++digits;
    temp /= 10;
} while (temp);

for (int i = 0; i < digits-1; i++)
{
    td *= 10;
}

s = num;
for (int i = 0; i < digits; i++)
{
    d[i] = s / td %10;
    td /= 10;

}

Remove all line breaks from a long string of text

The problem with rstrip is that it does not work in all cases (as I myself have seen few). Instead you can use - text= text.replace("\n"," ") this will remove all new line \n with a space.

Thanks in advance guys for your upvotes.

Uninstall old versions of Ruby gems

For removing older versions of all installed gems, following 2 commands are useful:

 gem cleanup --dryrun

Above command will preview what gems are going to be removed.

 gem cleanup

Above command will actually remove them.

Pass data from Activity to Service using an Intent

If you are using kotlin you can try the following code,

In the sending activity,

  val intent = Intent(context, RecorderService::class.java);
  intent.putExtra("filename", filename);
  context.startService(intent)

In the service,

override fun onStartCommand(intent: Intent, flags: Int, startId: Int): Int {
    super.onStartCommand(intent, flags, startId)

    if (intent != null && intent.extras != null)
       val filename = intent.getStringExtra("filename")

}

Implement a loading indicator for a jQuery AJAX call

This is how I realised the loading indicator by an Glyphicon:

<!DOCTYPE html>
<html>

<head>
    <title>Demo</title>

    <link rel="stylesheet" href="https://ajax.aspnetcdn.com/ajax/bootstrap/3.3.6/css/bootstrap.min.css">
    <script src="https://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.12.4.min.js"></script>
    <script src="https://ajax.aspnetcdn.com/ajax/bootstrap/3.3.6/bootstrap.min.js"></script>

    <style>
        .gly-ani {
          animation: ani 2s infinite linear;
        }
        @keyframes ani {
          0% {
            transform: rotate(0deg);
          }
          100% {
            transform: rotate(359deg);
          }
        }
    </style>  
</head>

<body>
<div class="container">

    <span class="glyphicon glyphicon-refresh gly-ani" style="font-size:40px;"></span>

</div>
</body>

</html>

Format a datetime into a string with milliseconds

In python 3.6 and above using python f-strings:

from datetime import datetime 

i = datetime.utcnow()

print(f"""{i:%Y-%m-%d %H:%M:%S}.{"{:03d}".format(i.microsecond // 1000)}""")

The code specific to format milliseconds is:

{"{:03d}".format(i.microsecond // 1000)}

The format string {:03d} and microsecond to millisecond conversion // 1000 is from def _format_time in https://github.com/python/cpython/blob/master/Lib/datetime.py that is used for datetime.datetime.isoformat().

How do I fix 'Invalid character value for cast specification' on a date column in flat file?

I was ultimately able to resolve the solution by setting the column type in the flat file connection to be of type "database date [DT_DBDATE]"

Apparently the differences between these date formats are as follow:

DT_DATE A date structure that consists of year, month, day, and hour.

DT_DBDATE A date structure that consists of year, month, and day.

DT_DBTIMESTAMP A timestamp structure that consists of year, month, hour, minute, second, and fraction

By changing the column type to DT_DBDATE the issue was resolved - I attached a Data Viewer and the CYCLE_DATE value was now simply "12/20/2010" without a time component, which apparently resolved the issue.

How to return multiple values in one column (T-SQL)?

Sorry, read the question wrong the first time. You can do something like this:

declare @result varchar(max)

--must "initialize" result for this to work
select @result = ''

select @result = @result + alias
FROM aliases
WHERE username='Bob'

delete map[key] in go?

Strangely enough,

package main

func main () {
    var sessions = map[string] chan int{};
    delete(sessions, "moo");
}

seems to work. This seems a poor use of resources though!

Another way is to check for existence and use the value itself:

package main

func main () {
    var sessions = map[string] chan int{};
    sessions["moo"] = make (chan int);
    _, ok := sessions["moo"];
    if ok {
        delete(sessions, "moo");
    }
}