Programs & Examples On #Exit handler

How to call a parent method from child class in javascript?

How about something based on Douglas Crockford idea:

    function Shape(){}

    Shape.prototype.name = 'Shape';

    Shape.prototype.toString = function(){
        return this.constructor.parent
            ? this.constructor.parent.toString() + ',' + this.name
            : this.name;
    };


    function TwoDShape(){}

    var F = function(){};

    F.prototype = Shape.prototype;

    TwoDShape.prototype = new F();

    TwoDShape.prototype.constructor = TwoDShape;

    TwoDShape.parent = Shape.prototype;

    TwoDShape.prototype.name = '2D Shape';


    var my = new TwoDShape();

    console.log(my.toString()); ===> Shape,2D Shape

The remote certificate is invalid according to the validation procedure

.NET is seeing an invalid SSL certificate on the other end of the connection. There is a workaround for it, but obviously not recommended for production code:

// Put this somewhere that is only once - like an initialization method
ServicePointManager.ServerCertificateValidationCallback += new RemoteCertificateValidationCallback(ValidateCertificate);
...

static bool ValidateCertificate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors)
{
   return true;
}

remove space between paragraph and unordered list

Every browser has some default styles that apply to a number of HTML elements, likes p and ul. The space you mention is likely created because of the default margin and padding of your browser. You can reset these though:

p { margin: 0; padding: 0; }
ul { margin: 0; padding: 0; }

You could also reset all default margins and paddings:

* { margin: 0; padding: 0; }

I suggest you take a look at normalize.css: http://necolas.github.com/normalize.css/

Java String declaration

String s1 = "Welcome"; // Does not create a new instance  
String s2 = new String("Welcome"); // Creates two objects and one reference variable  

Change the Blank Cells to "NA"

While many options above function well, I found coercion of non-target variables to chr problematic. Using ifelse and grepl within lapply resolves this off-target effect (in limited testing). Using slarky's regular expression in grepl:

set.seed(42)
x1 <- sample(c("a","b"," ", "a a", NA), 10, TRUE)
x2 <- sample(c(rnorm(length(x1),0, 1), NA), length(x1), TRUE)

df <- data.frame(x1, x2, stringsAsFactors = FALSE)

The problem of coercion to character class:

df2 <- lapply(df, function(x) gsub("^$|^ $", NA, x))
lapply(df2, class)

$x1 [1] "character"

$x2 [1] "character"

Resolution with use of ifelse:

df3 <- lapply(df, function(x) ifelse(grepl("^$|^ $", x)==TRUE, NA, x))
lapply(df3, class)

$x1 [1] "character"

$x2 [1] "numeric"

What are bitwise shift (bit-shift) operators and how do they work?

Note that in the Java implementation, the number of bits to shift is mod'd by the size of the source.

For example:

(long) 4 >> 65

equals 2. You might expect shifting the bits to the right 65 times would zero everything out, but it's actually the equivalent of:

(long) 4 >> (65 % 64)

This is true for <<, >>, and >>>. I have not tried it out in other languages.

(unicode error) 'unicodeescape' codec can't decode bytes in position 2-3: truncated \UXXXXXXXX escape

Try writing the file path as "C:\\Users\miche\Documents\school\jaar2\MIK\2.6\vektis_agb_zorgverlener" i.e with double backslash after the drive as opposed to "C:\Users\miche\Documents\school\jaar2\MIK\2.6\vektis_agb_zorgverlener"

Using form input to access camera and immediately upload photos using web app

It's really easy to do this, simply send the file via an XHR request inside of the file input's onchange handler.

<input id="myFileInput" type="file" accept="image/*;capture=camera">

var myInput = document.getElementById('myFileInput');

function sendPic() {
    var file = myInput.files[0];

    // Send file here either by adding it to a `FormData` object 
    // and sending that via XHR, or by simply passing the file into 
    // the `send` method of an XHR instance.
}

myInput.addEventListener('change', sendPic, false);

How to create a .gitignore file

Create a .gitignore file in include all files and directories that you don't want to commit.

Example:

#################
## Eclipse
#################

*.pydevproject
.project
.metadata
.gradle
bin/
tmp/
target/
*.tmp
*.bak
*.swp
*~.nib
local.properties
.classpath
.settings/
.loadpath

# External tool builders
.externalToolBuilders/

# Locally stored "Eclipse launch configurations"
*.launch

# CDT-specific
.cproject

# PDT-specific
.buildpath


#################
## Visual Studio
#################

## Ignore Visual Studio temporary files, build results, and
## files generated by popular Visual Studio add-ons.

# User-specific files
*.suo
*.user
*.sln.docstates

# Build results

[Dd]ebug/
[Rr]elease/
x64/
build/
[Bb]in/
[Oo]bj/

# MSTest test Results
[Tt]est[Rr]esult*/
[Bb]uild[Ll]og.*

*_i.c
*_p.c
*.ilk
*.meta
*.obj
*.pch
*.pdb
*.pgc
*.pgd
*.rsp
*.sbr
*.tlb
*.tli
*.tlh
*.tmp
*.tmp_proj
*.log
*.vspscc
*.vssscc
.builds
*.pidb
*.log
*.scc

# Visual C++ cache files
ipch/
*.aps
*.ncb
*.opensdf
*.sdf
*.cachefile

# Visual Studio profiler
*.psess
*.vsp
*.vspx

# Guidance Automation Toolkit
*.gpState

# ReSharper is a .NET coding add-in
_ReSharper*/
*.[Rr]e[Ss]harper

# TeamCity is a build add-in
_TeamCity*

# DotCover is a Code Coverage Tool
*.dotCover

# NCrunch
*.ncrunch*
.*crunch*.local.xml

# Installshield output folder
[Ee]xpress/

# DocProject is a documentation generator add-in
DocProject/buildhelp/
DocProject/Help/*.HxT
DocProject/Help/*.HxC
DocProject/Help/*.hhc
DocProject/Help/*.hhk
DocProject/Help/*.hhp
DocProject/Help/Html2
DocProject/Help/html

# Click-Once directory
publish/

# Publish Web Output
*.Publish.xml
*.pubxml

# NuGet Packages Directory
## TODO: If you have NuGet Package Restore enabled, uncomment the next line
#packages/

# Windows Azure Build Output
csx
*.build.csdef

# Windows Store app package directory
AppPackages/

# Others
sql/
*.Cache
ClientBin/
[Ss]tyle[Cc]op.*
~$*
*~
*.dbmdl
*.[Pp]ublish.xml
*.pfx
*.publishsettings

how to initialize a char array?

what is the best way to do this in C++?

Because you asked it this way:

std::string msg(65546, 0); // all characters will be set to 0

Or:

std::vector<char> msg(65546); // all characters will be initialized to 0

If you are working with C functions which accept char* or const char*, then you can do:

some_c_function(&msg[0]);

You can also use the c_str() method on std::string if it accepts const char* or data().

The benefit of this approach is that you can do everything you want to do with a dynamically allocating char buffer but more safely, flexibly, and sometimes even more efficiently (avoiding the need to recompute string length linearly, e.g.). Best of all, you don't have to free the memory allocated manually, as the destructor will do this for you.

How to randomly pick an element from an array

public static int getRandom(int[] array) {
    int rnd = new Random().nextInt(array.length);
    return array[rnd];
}

What are examples of TCP and UDP in real life?

TCP is appropriate when you have to move a decent amount of data (> ~1 kB), and you require all of it to be delivered. Almost all data that moves across the internet does so via TCP - HTTP, SMTP, BitTorrent, SSH, etc, all use TCP.

UDP is appropriate when you have small messages which you can afford to lose, and would like to send them as efficiently as possible. One reason you might be able to afford to lose them is because you can re-send them if they get lost. The main example on the internet is DNS - DNS consists of small queries saying things like "what is the IP number for stackoverflow.com?", and the responses are correspondingly small. Computers make a lot of these queries, so they should be made efficiently, but if they get lost en route, it's easy to time out and re-send them.

Tensorflow 2.0 - AttributeError: module 'tensorflow' has no attribute 'Session'

If this is your code, the correct solution is to rewrite it to not use Session(), since that's no longer necessary in TensorFlow 2

If this is just code you're running, you can downgrade to TensorFlow 1 by running

pip3 install --upgrade --force-reinstall tensorflow-gpu==1.15.0 

(or whatever the latest version of TensorFlow 1 is)

PHP form - on submit stay on same page

There are two ways of doing it:

  1. Submit the form to the same page: Handle the submitted form using PHP script. (This can be done by setting the form action to the current page URL.)

    if(isset($_POST['submit'])) {
        // Enter the code you want to execute after the form has been submitted
        // Display Success or Failure message (if any)
      } else {
        // Display the Form and the Submit Button
    }
    
  2. Using AJAX Form Submission which is a little more difficult for a beginner than method #1.

How to cache data in a MVC application

I have used it in this way and it works for me. https://msdn.microsoft.com/en-us/library/system.web.caching.cache.add(v=vs.110).aspx parameters info for system.web.caching.cache.add.

public string GetInfo()
{
     string name = string.Empty;
     if(System.Web.HttpContext.Current.Cache["KeyName"] == null)
     {
         name = GetNameMethod();
         System.Web.HttpContext.Current.Cache.Add("KeyName", name, null, DateTime.Noew.AddMinutes(5), Cache.NoSlidingExpiration, CacheitemPriority.AboveNormal, null);
     }
     else
     {
         name = System.Web.HttpContext.Current.Cache["KeyName"] as string;
     }

      return name;

}

When should I use Kruskal as opposed to Prim (and vice versa)?

Use Prim's algorithm when you have a graph with lots of edges.

For a graph with V vertices E edges, Kruskal's algorithm runs in O(E log V) time and Prim's algorithm can run in O(E + V log V) amortized time, if you use a Fibonacci Heap.

Prim's algorithm is significantly faster in the limit when you've got a really dense graph with many more edges than vertices. Kruskal performs better in typical situations (sparse graphs) because it uses simpler data structures.

Why does AngularJS include an empty option in select?

This worked for me

<select ng-init="basicProfile.casteId" ng-model="basicProfile.casteId" class="form-control">
     <option value="0">Select Caste....</option>
     <option data-ng-repeat="option in formCastes" value="{{option.id}}">{{option.casteName}}</option>
 </select>

How to replace � in a string

profilage bas� sur l'analyse de l'esprit (french)

should be translated as:

profilage basé sur l'analyse de l'esprit

so, in this case � = é

How to reload the datatable(jquery) data?

You could use this function:

function RefreshTable(tableId, urlData)
    {
      //Retrieve the new data with $.getJSON. You could use it ajax too
      $.getJSON(urlData, null, function( json )
      {
        table = $(tableId).dataTable();
        oSettings = table.fnSettings();

        table.fnClearTable(this);

        for (var i=0; i<json.aaData.length; i++)
        {
          table.oApi._fnAddData(oSettings, json.aaData[i]);
        }

        oSettings.aiDisplay = oSettings.aiDisplayMaster.slice();
        table.fnDraw();
      });
    }

Dont' forget to call it after your delete function has succeded.

Source: http://www.meadow.se/wordpress/?p=536

parseInt with jQuery

Two issues:

  1. You're passing the jQuery wrapper of the element into parseInt, which isn't what you want, as parseInt will call toString on it and get back "[object Object]". You need to use val or text or something (depending on what the element is) to get the string you want.

  2. You're not telling parseInt what radix (number base) it should use, which puts you at risk of odd input giving you odd results when parseInt guesses which radix to use.

Fix if the element is a form field:

//                               vvvvv-- use val to get the value
var test = parseInt($("#testid").val(), 10);
//                                    ^^^^-- tell parseInt to use decimal (base 10)

Fix if the element is something else and you want to use the text within it:

//                               vvvvvv-- use text to get the text
var test = parseInt($("#testid").text(), 10);
//                                     ^^^^-- tell parseInt to use decimal (base 10)

HTML: Select multiple as dropdown

You probably need to some plugin like Jquery multiselect dropdown. Here is a demo.

Also you need to close your option tags like this:

<select name="test" multiple>
    <option>123</option>
    <option>456</option>
    <option>789</option>
</select>

JSFIDDLE DEMO

How to test android apps in a real device with Android Studio?

To test an android apps in a real device with Android Studio, You must keep two things in mind

  1. You should enable USB debugging option on your android phone.
  2. You must have driver installed on your computer.

Now , let me tell you how you can enable USB debugging on your android phone:

  1. Go to Settings on your android phone
  2. Scroll down to the bottom and click on About phone
  3. On this menu also scroll down to the bottom, you should see something Build number
  4. Click on Build number 7 times
  5. Now your Developer Option enables, once you done click on back button and you should see a new option on your android screen i.e. Developer Options
  6. Click On Developer Options
  7. Scroll down until you see USB Debugging
  8. Go ahead and click the check box next to the USB debugging
  9. Now your USB Debugging option enables.
  10. Connect your android device to your computer with the help of USB connector.

Now let me tell you how you can download the driver on your Windows PC:

  1. Your windows machine need a software called driver to communicate with your phone.
  2. Go To OEM USB Driver Website to install your appropriate driver
  3. Scroll down and select the driver appropriate for your device. Check the screen shoot
  4. Once you download it , you have to unzip your file
  5. After Installing Google USB Driver, close SDK Manager window, Connect your phone or tablet through USB cable to your laptop or PC.
  6. Now click on My Computer (Windows 7) (or) This PC(Windows 8.1).Select Manage.
  7. Select Device Manager –> Portable Devices –> Your Device Name
  8. Right Click on Your Device Name and Select Browse My Computer For Driver Software.
  9. Point it to C:\Users\YourUserName\AppData\Local\Android\sdk\extras\google\usb_driver. Hit Next and Finish.
  10. Now Hit Run Button after selecting Your Project in Project Explorer in Android studio. Choose your device and press OK.

Elastic Search: how to see the indexed data

Probably the easiest way to explore your ElasticSearch cluster is to use elasticsearch-head.

You can install it by doing:

cd elasticsearch/
./bin/plugin -install mobz/elasticsearch-head

Then (assuming ElasticSearch is already running on your local machine), open a browser window to:

http://localhost:9200/_plugin/head/

Alternatively, you can just use curl from the command line, eg:

Check the mapping for an index:

curl -XGET 'http://127.0.0.1:9200/my_index/_mapping?pretty=1' 

Get some sample docs:

curl -XGET 'http://127.0.0.1:9200/my_index/_search?pretty=1' 

See the actual terms stored in a particular field (ie how that field has been analyzed):

curl -XGET 'http://127.0.0.1:9200/my_index/_search?pretty=1'  -d '
 {
    "facets" : {
       "my_terms" : {
          "terms" : {
             "size" : 50,
             "field" : "foo"
          }
       }
    }
 }

More available here: http://www.elasticsearch.org/guide

UPDATE : Sense plugin in Marvel

By far the easiest way of writing curl-style commands for Elasticsearch is the Sense plugin in Marvel.

It comes with source highlighting, pretty indenting and autocomplete.

Note: Sense was originally a standalone chrome plugin but is now part of the Marvel project.

How can I remove a specific item from an array?

Remove one value, using loose comparison, without mutating the original array, ES6

/**
 * Removes one instance of `value` from `array`, without mutating the original array. Uses loose comparison.
 *
 * @param {Array} array Array to remove value from
 * @param {*} value Value to remove
 * @returns {Array} Array with `value` removed
 */
export function arrayRemove(array, value) {
    for(let i=0; i<array.length; ++i) {
        if(array[i] == value) {
            let copy = [...array];
            copy.splice(i, 1);
            return copy;
        }
    }
    return array;
}

How can I make an image transparent on Android?

For 20% transparency, this worked for me:

Button bu = (Button)findViewById(R.id.button1);
bu.getBackground().setAlpha(204);

Allowed memory size of X bytes exhausted

I had same issue. I found the answer:

ini_set('memory_limit', '-1');

Note: It will take unlimited memory usage of server.

Update: Use this carefully as this might slow down your system if the PHP script starts using an excessive amount of memory, causing a lot of swap space usage. You can use this if you know program will not take much memory and also you don't know how much to set it right now. But you will eventually find it how much memory you require for that program.

You should always memory limit as some value as answered by @sarki dinle.

ini_set('memory_limit', '512M');

Giving unlimited memory is bad practice, rather we should give some max limit that we can bear and then optimise our code or add some RAMs.

"End of script output before headers" error in Apache

In my case I had a similar problem but with c ++ this in windows 10, the problem was solved by adding the environment variables (path) windows, the folder of the c ++ libraries, in my case I used the codeblock libraries:

C:\codeblocks\MinGW\bin

Find directory name with wildcard or similar to "like"

find supports wildcard matches, just add a *:

find / -type d -name "ora10*"

Multiple file upload in php

$property_images = $_FILES['property_images']['name'];
    if(!empty($property_images))
    {
        for($up=0;$up<count($property_images);$up++)
        {
            move_uploaded_file($_FILES['property_images']['tmp_name'][$up],'../images/property_images/'.$_FILES['property_images']['name'][$up]);
        }
    }

Value does not fall within the expected range

I had from a totaly different reason the same notice "Value does not fall within the expected range" from the Visual studio 2008 while trying to use the: Tools -> Windows Embedded Silverlight Tools -> Update Silverlight For Windows Embedded Project.

After spending many ohurs I found out that the problem was that there wasn't a resource file and the update tool looks for the .RC file

Therefor the solution is to add to the resource folder a .RC file and than it works perfectly. I hope it will help someone out there

Django - taking values from POST request

Read about request objects that your views receive: https://docs.djangoproject.com/en/dev/ref/request-response/#httprequest-objects

Also your hidden field needs a reliable name and then a value:

<input type="hidden" name="title" value="{{ source.title }}">

Then in a view:

request.POST.get("title", "")

How to start IDLE (Python editor) without using the shortcut on Windows Vista?

In Python 3.2.2, I found \Python32\Lib\idlelib\idle.bat which was useful because it would let me open python files supplied as args in IDLE.

port forwarding in windows

I've solved it, it can be done executing:

netsh interface portproxy add v4tov4 listenport=4422 listenaddress=192.168.1.111 connectport=80 connectaddress=192.168.0.33

To remove forwarding:

netsh interface portproxy delete v4tov4 listenport=4422 listenaddress=192.168.1.111

Official docs

Add a link to an image in a css style sheet

You don't add links to style sheets. They are for describing the style of the page. You would change your mark-up or add JavaScript to navigate when the image is clicked.

Based only on your style you would have:

<a href="home.com" id="logo"></a>

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

1) Also you can use lateinit If you sure do your initialization later on onCreate() or elsewhere.

Use this

lateinit var left: Node

Instead of this

var left: Node? = null

2) And there is other way that use !! end of variable when you use it like this

queue.add(left!!) // add !!

bad operand types for binary operator "&" java

Because & has a lesser priority than ==.

Your code is equivalent to a[0] & (1 == 0), and unless a[0] is a boolean this won't compile...

You need to:

(a[0] & 1) == 0

etc etc.

(yes, Java does hava a boolean & operator -- a non shortcut logical and)

SQL Server 2005 Using CHARINDEX() To split a string

Here's a little function that will do "NATO encoding" for you:

CREATE FUNCTION dbo.NATOEncode (
   @String varchar(max)
)
RETURNS TABLE
WITH SCHEMABINDING
AS
RETURN (
   WITH L1 (N) AS (SELECT 1 UNION ALL SELECT 1),
   L2 (N) AS (SELECT 1 FROM L1, L1 B),
   L3 (N) AS (SELECT 1 FROM L2, L2 B),
   L4 (N) AS (SELECT 1 FROM L3, L3 B),
   L5 (N) AS (SELECT 1 FROM L4, L4 C),
   L6 (N) AS (SELECT 1 FROM L5, L5 C),
   Nums (Num) AS (SELECT Row_Number() OVER (ORDER BY (SELECT 1)) FROM L6)
   SELECT
      NATOString = Substring((
         SELECT
            Convert(varchar(max), ' ' + D.Word)
         FROM
            Nums N
            INNER JOIN (VALUES
               ('A', 'Alpha'),
               ('B', 'Beta'),
               ('C', 'Charlie'),
               ('D', 'Delta'),
               ('E', 'Echo'),
               ('F', 'Foxtrot'),
               ('G', 'Golf'),
               ('H', 'Hotel'),
               ('I', 'India'),
               ('J', 'Juliet'),
               ('K', 'Kilo'),
               ('L', 'Lima'),
               ('M', 'Mike'),
               ('N', 'November'),
               ('O', 'Oscar'),
               ('P', 'Papa'),
               ('Q', 'Quebec'),
               ('R', 'Romeo'),
               ('S', 'Sierra'),
               ('T', 'Tango'),
               ('U', 'Uniform'),
               ('V', 'Victor'),
               ('W', 'Whiskey'),
               ('X', 'X-Ray'),
               ('Y', 'Yankee'),
               ('Z', 'Zulu'),
               ('0', 'Zero'),
               ('1', 'One'),
               ('2', 'Two'),
               ('3', 'Three'),
               ('4', 'Four'),
               ('5', 'Five'),
               ('6', 'Six'),
               ('7', 'Seven'),
               ('8', 'Eight'),
               ('9', 'Niner')
            ) D (Digit, Word)
               ON Substring(@String, N.Num, 1) = D.Digit
         WHERE
            N.Num <= Len(@String)
         FOR XML PATH(''), TYPE
      ).value('.[1]', 'varchar(max)'), 2, 2147483647)
);

This function will work on even very long strings, and performs pretty well (I ran it against a 100,000-character string and it returned in 589 ms). Here's an example of how to use it:

SELECT NATOString FROM dbo.NATOEncode('LD-23DSP-1430');
-- Output: Lima Delta Two Three Delta Sierra Papa One Four Three Zero

I intentionally made it a table-valued function so it could be inlined into a query if you run it against many rows at once, just use CROSS APPLY or wrap the above example in parentheses to use it as a value in the SELECT clause (you can put a column name in the function parameter position).

Casting objects in Java

Have a look at this sample:

public class A {
  //statements
}

public class B extends A {
  public void foo() { }
}

A a=new B();

//To execute **foo()** method.

((B)a).foo();

Limiting the output of PHP's echo to 200 characters

more flexible way is a function with two parameters:

function lchar($str,$val){return strlen($str)<=$val?$str:substr($str,0,$val).'...';}

usage:

echo lchar($str,200);

What is the best way to compare 2 folder trees on windows?

SyncToy is a free application from Microsoft with a "Preview" mode for comparing two paths. For example:

SyncToy Preview screenshot (source: https://maketecheasier-2d0f.kxcdn.com/assets/uploads/2010/06/synctoy-preview.png)

You can then choose one of three modes ("Synchronize", "Echo" and "Contribute") to resolve the differences.

Lastly, it comes with SyncToyCmd for creating and synchronizing folder pairs from the CLI or a Scheduled Task.

jQuery select all except first

_x000D_
_x000D_
$(document).ready(function(){_x000D_
_x000D_
  $(".btn1").click(function(){_x000D_
          $("div.test:not(:first)").hide();_x000D_
  });_x000D_
_x000D_
  $(".btn2").click(function(){_x000D_
           $("div.test").show();_x000D_
          $("div.test:not(:first):not(:last)").hide();_x000D_
  });_x000D_
_x000D_
  $(".btn3").click(function(){_x000D_
          $("div.test").hide();_x000D_
          $("div.test:not(:first):not(:last)").show();_x000D_
  });_x000D_
_x000D_
});
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
_x000D_
<button class="btn1">Hide All except First</button>_x000D_
<button class="btn2">Hide All except First & Last</button>_x000D_
<button class="btn3">Hide First & Last</button>_x000D_
_x000D_
<br/>_x000D_
_x000D_
<div class='test'>First</div>_x000D_
<div class='test'>Second</div>_x000D_
<div class='test'>Third</div>_x000D_
<div class='test'>Last</div>
_x000D_
_x000D_
_x000D_

Make an html number input always display 2 decimal places

Pure html is not able to do what you want. My suggestion would be to write a simple javascript function to do the roudning for you.

Java Currency Number format

Yes. You can use java.util.formatter. You can use a formatting string like "%10.2f"

How are people unit testing with Entity Framework 6, should you bother?

There is Effort which is an in memory entity framework database provider. I've not actually tried it... Haa just spotted this was mentioned in the question!

Alternatively you could switch to EntityFrameworkCore which has an in memory database provider built-in.

https://blog.goyello.com/2016/07/14/save-time-mocking-use-your-real-entity-framework-dbcontext-in-unit-tests/

https://github.com/tamasflamich/effort

I used a factory to get a context, so i can create the context close to its use. This seems to work locally in visual studio but not on my TeamCity build server, not sure why yet.

return new MyContext(@"Server=(localdb)\mssqllocaldb;Database=EFProviders.InMemory;Trusted_Connection=True;");

Import Excel Spreadsheet Data to an EXISTING sql table?

You can use import data with wizard and there you can choose destination table.

Run the wizard. In selecting source tables and views window you see two parts. Source and Destination.

Click on the field under Destination part to open the drop down and select you destination table and edit its mappings if needed.

EDIT

Merely typing the name of the table does not work. It appears that the name of the table must include the schema (dbo) and possibly brackets. Note the dropdown on the right hand side of the text field.

enter image description here

Vertically aligning CSS :before and :after content

I had a similar problem. Here is what I did. Since the element I was trying to center vertically had height = 60px, I managed to center it vertically using:

top: calc(50% - 30px);

How to programmatically round corners and set random background colors

Instead of setBackgroundColor, retrieve the background drawable and set its color:

v.setBackgroundResource(R.drawable.tags_rounded_corners);

GradientDrawable drawable = (GradientDrawable) v.getBackground();
if (i % 2 == 0) {
  drawable.setColor(Color.RED);
} else {
  drawable.setColor(Color.BLUE);
}

Also, you can define the padding within your tags_rounded_corners.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
  <corners android:radius="4dp" />
  <padding
    android:top="2dp"
    android:left="2dp"
    android:bottom="2dp"
    android:right="2dp" />
</shape> 

Rails :include vs. :joins

.joins will just joins the tables and brings selected fields in return. if you call associations on joins query result, it will fire database queries again

:includes will eager load the included associations and add them in memory. :includes loads all the included tables attributes. If you call associations on include query result, it will not fire any queries

Flutter: RenderBox was not laid out

i

I used this code to fix the issue of displaying items in the horizontal list.

new Container(
      height: 20,
      child: Row(
        mainAxisAlignment: MainAxisAlignment.end,
        children: <Widget>[
          ListView.builder(
            scrollDirection: Axis.horizontal,
            shrinkWrap: true,
            itemCount: array.length,
            itemBuilder: (context, index){
              return array[index];
            },
          ),
        ],
      ),
    );

Use index in pandas to plot data

Try this,

monthly_mean.plot(y='A', use_index=True)

How do I search an SQL Server database for a string?

This will search every column of every table in a specific database. Create the stored procedure on the database that you want to search in.

The Ten Most Asked SQL Server Questions And Their Answers:

CREATE PROCEDURE FindMyData_String
    @DataToFind NVARCHAR(4000),
    @ExactMatch BIT = 0
AS
SET NOCOUNT ON

DECLARE @Temp TABLE(RowId INT IDENTITY(1,1), SchemaName sysname, TableName sysname, ColumnName SysName, DataType VARCHAR(100), DataFound BIT)

    INSERT  INTO @Temp(TableName,SchemaName, ColumnName, DataType)
    SELECT  C.Table_Name,C.TABLE_SCHEMA, C.Column_Name, C.Data_Type
    FROM    Information_Schema.Columns AS C
            INNER Join Information_Schema.Tables AS T
                ON C.Table_Name = T.Table_Name
        AND C.TABLE_SCHEMA = T.TABLE_SCHEMA
    WHERE   Table_Type = 'Base Table'
            And Data_Type In ('ntext','text','nvarchar','nchar','varchar','char')


DECLARE @i INT
DECLARE @MAX INT
DECLARE @TableName sysname
DECLARE @ColumnName sysname
DECLARE @SchemaName sysname
DECLARE @SQL NVARCHAR(4000)
DECLARE @PARAMETERS NVARCHAR(4000)
DECLARE @DataExists BIT
DECLARE @SQLTemplate NVARCHAR(4000)

SELECT  @SQLTemplate = CASE WHEN @ExactMatch = 1
                            THEN 'If Exists(Select *
                                          From   ReplaceTableName
                                          Where  Convert(nVarChar(4000), [ReplaceColumnName])
                                                       = ''' + @DataToFind + '''
                                          )
                                     Set @DataExists = 1
                                 Else
                                     Set @DataExists = 0'
                            ELSE 'If Exists(Select *
                                          From   ReplaceTableName
                                          Where  Convert(nVarChar(4000), [ReplaceColumnName])
                                                       Like ''%' + @DataToFind + '%''
                                          )
                                     Set @DataExists = 1
                                 Else
                                     Set @DataExists = 0'
                            END,
        @PARAMETERS = '@DataExists Bit OUTPUT',
        @i = 1

SELECT @i = 1, @MAX = MAX(RowId)
FROM   @Temp

WHILE @i <= @MAX
    BEGIN
        SELECT  @SQL = REPLACE(REPLACE(@SQLTemplate, 'ReplaceTableName', QUOTENAME(SchemaName) + '.' + QUOTENAME(TableName)), 'ReplaceColumnName', ColumnName)
        FROM    @Temp
        WHERE   RowId = @i


        PRINT @SQL
        EXEC SP_EXECUTESQL @SQL, @PARAMETERS, @DataExists = @DataExists OUTPUT

        IF @DataExists =1
            UPDATE @Temp SET DataFound = 1 WHERE RowId = @i

        SET @i = @i + 1
    END

SELECT  SchemaName,TableName, ColumnName
FROM    @Temp
WHERE   DataFound = 1
GO

To run it, just do this:

exec FindMyData_string 'google', 0

It works amazingly well!!!

Distinct in Linq based on only one field of the table

but I need results where r.text is not duplicated

Sounds as if you want this:

table1.GroupBy(x => x.Text)
      .Where(g => g.Count() == 1)
      .Select(g => g.First());

This will select rows where the Text is unique.

Convert a dta file to csv without Stata software

I have not tried, but if you know Perl you can use the Parse-Stata-DtaReader module to convert the file for you.

The module has a command-line tool dta2csv, which can "convert Stata 8 and Stata 10 .dta files to csv"

How to open a specific port such as 9090 in Google Compute Engine

You need to:

  1. Go to cloud.google.com

  2. Go to my Console

  3. Choose your Project

  4. Choose Networking > VPC network

  5. Choose "Firewalls rules"

  6. Choose "Create Firewall Rule"

  7. To apply the rule to select VM instances, select Targets > "Specified target tags", and enter into "Target tags" the name of the tag. This tag will be used to apply the new firewall rule onto whichever instance you'd like. Then, make sure the instances have the network tag applied.

  8. To allow incoming TCP connections to port 9090, in "Protocols and Ports" enter tcp:9090

  9. Click Create

I hope this helps you.

Update Please refer to docs to customize your rules.

FileProvider - IllegalArgumentException: Failed to find configured root

My issue was that I had overlapping names in the file paths for different types, like this:

<cache-path
    name="cached_files"
    path="." />
<external-cache-path
    name="cached_files"
    path="." />

After I changed the names ("cached_files") to be unique, I got rid of the error. My guess is that those paths are stored in some HashMap or something which does not allow duplicates.

open program minimized via command prompt

If the application is already open (even in background), it will be restored by "start" command. Exit the program if running then /max or /min will work

Drop rows containing empty cells from a pandas DataFrame

Pythonic + Pandorable: df[df['col'].astype(bool)]

Empty strings are falsy, which means you can filter on bool values like this:

df = pd.DataFrame({
    'A': range(5),
    'B': ['foo', '', 'bar', '', 'xyz']
})
df
   A    B
0  0  foo
1  1     
2  2  bar
3  3     
4  4  xyz
df['B'].astype(bool)                                                                                                                      
0     True
1    False
2     True
3    False
4     True
Name: B, dtype: bool

df[df['B'].astype(bool)]                                                                                                                  
   A    B
0  0  foo
2  2  bar
4  4  xyz

If your goal is to remove not only empty strings, but also strings only containing whitespace, use str.strip beforehand:

df[df['B'].str.strip().astype(bool)]
   A    B
0  0  foo
2  2  bar
4  4  xyz

Faster than you Think

.astype is a vectorised operation, this is faster than every option presented thus far. At least, from my tests. YMMV.

Here is a timing comparison, I've thrown in some other methods I could think of.

enter image description here

Benchmarking code, for reference:

import pandas as pd
import perfplot

df1 = pd.DataFrame({
    'A': range(5),
    'B': ['foo', '', 'bar', '', 'xyz']
})

perfplot.show(
    setup=lambda n: pd.concat([df1] * n, ignore_index=True),
    kernels=[
        lambda df: df[df['B'].astype(bool)],
        lambda df: df[df['B'] != ''],
        lambda df: df[df['B'].replace('', np.nan).notna()],  # optimized 1-col
        lambda df: df.replace({'B': {'': np.nan}}).dropna(subset=['B']),  
    ],
    labels=['astype', "!= ''", "replace + notna", "replace + dropna", ],
    n_range=[2**k for k in range(1, 15)],
    xlabel='N',
    logx=True,
    logy=True,
    equality_check=pd.DataFrame.equals)

htaccess Access-Control-Allow-Origin

In Zend Framework 2.0 i had this problem. Can be solved in two way .htaccess or php header i prefer .htaccess so i modified .htaccess from:

RewriteEngine On
RewriteCond %{REQUEST_FILENAME} -s [OR]
RewriteCond %{REQUEST_FILENAME} -l [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^.*$ - [NC,L]
RewriteRule ^.*$ index.php [NC,L]

to

RewriteEngine On

<IfModule mod_headers.c>
    Header set Access-Control-Allow-Origin "*"
</IfModule>

RewriteCond %{REQUEST_FILENAME} -s [OR]
RewriteCond %{REQUEST_FILENAME} -l [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^.*$ - [NC,L]
RewriteRule ^.*$ index.php [NC,L]

and it start to work

Android: How can I pass parameters to AsyncTask's onPreExecute()?

You can override the constructor. Something like:

private class MyAsyncTask extends AsyncTask<Void, Void, Void> {

    public MyAsyncTask(boolean showLoading) {
        super();
        // do stuff
    }

    // doInBackground() et al.
}

Then, when calling the task, do something like:

new MyAsyncTask(true).execute(maybe_other_params);

Edit: this is more useful than creating member variables because it simplifies the task invocation. Compare the code above with:

MyAsyncTask task = new MyAsyncTask();
task.showLoading = false;
task.execute();

'if' statement in jinja2 template

Why the loop?

You could simply do this:

{% if 'priority' in data %}
    <p>Priority: {{ data['priority'] }}</p>
{% endif %}

When you were originally doing your string comparison, you should have used == instead.

Find value in an array

I know this question has already been answered, but I came here looking for a way to filter elements in an Array based on some criteria. So here is my solution example: using select, I find all constants in Class that start with "RUBY_"

Class.constants.select {|c| c.to_s =~ /^RUBY_/ }

UPDATE: In the meantime I have discovered that Array#grep works much better. For the above example,

Class.constants.grep /^RUBY_/

did the trick.

django - get() returned more than one topic

I had same problem and solution was obj = ClassName.objects.filter()

Reading RFID with Android phones

First is understanding that RFID is very generic term. NFC is subset of RFID technology. NFC is used for prox card, credit cards, tap and go payment system. Your phones can read and emulate NFC (Apple pay, Google pay, etc.), if they support NFC. NFC is very short distance and low power - which is why you see tap and go type usage.

The more common RFID are the tags you see here and there. They come in a wide ranges of styles, uses and frequency.

HF - high frequency tags are what they use for "chipping" animals - cattle, dogs, cats. Read range is about 12 inches and requires an external antenna that is powered the bigger the antenna the more power it needs and the further it can read.

UFH tags look similar to HF tags but have a read range of several feet.

Also HF tags come single read and multi read. UFH is exclusviely multi read.

Mutiread means when a reader is active, you can litterally read about 1700 tags in under 10 seconds.

But this is a function of the size of the antenna and how much power you can push through the reader.

As to the direct question about Android and RFID - the best way to go is to get an external handheld reader that connects to your mobile device via Bluetooth. Bluetooth libraries exist for all mobile devices - Android, Apple, Windows. From there its just a matter of the manufacturer documentation about how to open a socket to the reader and how to decode the serial information.

The TSL line of readers is very popular because you don't have to deal with reading bytes and all that low level serial jazz that other manufactures do. They have a nice set of commands that are easy to use to control the reader.

Other manufactures are basic in that you open a serial socket and then read the output like you would see in terminal app like PuTTY.

Cannot construct instance of - Jackson

Your @JsonSubTypes declaration does not make sense: it needs to list implementation (sub-) classes, NOT the class itself (which would be pointless). So you need to modify that entry to list sub-class(es) there are; or use some other mechanism to register sub-classes (SimpleModule has something like addAbstractTypeMapping).

How do I force git to checkout the master branch and remove carriage returns after I've normalized files using the "text" attribute?

As others have pointed out one could just delete all the files in the repo and then check them out. I prefer this method and it can be done with the code below

git ls-files -z | xargs -0 rm
git checkout -- .

or one line

git ls-files -z | xargs -0 rm ; git checkout -- .

I use it all the time and haven't found any down sides yet!

For some further explanation, the -z appends a null character onto the end of each entry output by ls-files, and the -0 tells xargs to delimit the output it was receiving by those null characters.

How do I get the name of the rows from the index of a data frame?

this seems to work fine :

dataframe.axes[0].tolist()

Abort Ajax requests using jQuery

I have shared a demo that demonstrates how to cancel an AJAX request-- if data is not returned from the server within a predefined wait time.

HTML :

<div id="info"></div>

JS CODE:

var isDataReceived= false, waitTime= 1000; 
$(function() {
    // Ajax request sent.
     var xhr= $.ajax({
      url: 'http://api.joind.in/v2.1/talks/10889',
      data: {
         format: 'json'
      },     
      dataType: 'jsonp',
      success: function(data) {      
        isDataReceived= true;
        $('#info').text(data.talks[0].talk_title);        
      },
      type: 'GET'
   });
   // Cancel ajax request if data is not loaded within 1sec.
   setTimeout(function(){
     if(!isDataReceived)
     xhr.abort();     
   },waitTime);   
});

Align the form to the center in Bootstrap 4

<div class="d-flex justify-content-center align-items-center container ">

    <div class="row ">


        <form action="">
            <div class="form-group">
                <label for="inputUserName" class="control-label">Enter UserName</label>
                <input type="email" class="form-control" id="inputUserName" aria-labelledby="emailnotification">
                <small id="emailnotification" class="form-text text-muted">Enter Valid Email Id</small>
            </div>
            <div class="form-group">
                <label for="inputPassword" class="control-label">Enter Password</label>
                <input type="password" class="form-control" id="inputPassword" aria-labelledby="passwordnotification">

            </div>
        </form>

    </div>

</div>

Android - running a method periodically using postDelayed() call

You should set andrid:allowRetainTaskState="true" to Launch Activity in Manifest.xml. If this Activty is not Launch Activity. you should set android:launchMode="singleTask" at this activity

Pure CSS to make font-size responsive based on dynamic amount of characters

For reference, a non-CSS solution:

Below is some JS that re-sizes a font depending on the text length within a container.

Codepen with slightly modified code, but same idea as below:

function scaleFontSize(element) {
    var container = document.getElementById(element);

    // Reset font-size to 100% to begin
    container.style.fontSize = "100%";

    // Check if the text is wider than its container,
    // if so then reduce font-size
    if (container.scrollWidth > container.clientWidth) {
        container.style.fontSize = "70%";
    }
}

For me, I call this function when a user makes a selection in a drop-down, and then a div in my menu gets populated (this is where I have dynamic text occurring).

    scaleFontSize("my_container_div");

In addition, I also use CSS ellipses ("...") to truncate yet even longer text too, like so:

#my_container_div {
    width: 200px; /* width required for text-overflow to work */
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

So, ultimately:

  • Short text: e.g. "APPLES"

    Fully rendered, nice big letters.

  • Long text: e.g. "APPLES & ORANGES"

    Gets scaled down 70%, via the above JS scaling function.

  • Super long text: e.g. "APPLES & ORANGES & BANAN..."

    Gets scaled down 70% AND gets truncated with a "..." ellipses, via the above JS scaling function together with the CSS rule.

You could also explore playing with CSS letter-spacing to make text narrower while keeping the same font size.

How do I change the formatting of numbers on an axis with ggplot?

I also found another way of doing this that gives proper 'x10(superscript)5' notation on the axes. I'm posting it here in the hope it might be useful to some. I got the code from here so I claim no credit for it, that rightly goes to Brian Diggs.

fancy_scientific <- function(l) {
     # turn in to character string in scientific notation
     l <- format(l, scientific = TRUE)
     # quote the part before the exponent to keep all the digits
     l <- gsub("^(.*)e", "'\\1'e", l)
     # turn the 'e+' into plotmath format
     l <- gsub("e", "%*%10^", l)
     # return this as an expression
     parse(text=l)
}

Which you can then use as

ggplot(data=df, aes(x=x, y=y)) +
   geom_point() +
   scale_y_continuous(labels=fancy_scientific) 

Changing background color of ListView items on Android

Simple code to change all in layout of item (custom listview extends baseadapter):

lv.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
                long arg3) {

            RelativeLayout layout=(RelativeLayout) arg1.findViewById(R.id.rel_cell_left);
            layout.setBackgroundColor(Color.YELLOW);



        }
    });

Module is not available, misspelled or forgot to load (but I didn't)

I had the same error and fixed it. It turned out to be a silly reason.

This was the culprit: <script src="app.js"/>

Fix: <script src="app.js"></script>

Make sure your script tag is ended properly!

chart.js load totally new data

I had huge problems with this

First I tried .clear() then I tried .destroy() and I tried setting my chart reference to null

What finally fixed the issue for me: deleting the <canvas> element and then reappending a new <canvas> to the parent container


There's a million ways to do this:

var resetCanvas = function () {
  $('#results-graph').remove(); // this is my <canvas> element
  $('#graph-container').append('<canvas id="results-graph"><canvas>');
  canvas = document.querySelector('#results-graph'); // why use jQuery?
  ctx = canvas.getContext('2d');
  ctx.canvas.width = $('#graph').width(); // resize to parent width
  ctx.canvas.height = $('#graph').height(); // resize to parent height

  var x = canvas.width/2;
  var y = canvas.height/2;
  ctx.font = '10pt Verdana';
  ctx.textAlign = 'center';
  ctx.fillText('This text is centered on the canvas', x, y);
};

Oracle row count of table by count(*) vs NUM_ROWS from DBA_TABLES

According to the documentation NUM_ROWS is the "Number of rows in the table", so I can see how this might be confusing. There, however, is a major difference between these two methods.

This query selects the number of rows in MY_TABLE from a system view. This is data that Oracle has previously collected and stored.

select num_rows from all_tables where table_name = 'MY_TABLE'

This query counts the current number of rows in MY_TABLE

select count(*) from my_table

By definition they are difference pieces of data. There are two additional pieces of information you need about NUM_ROWS.

  1. In the documentation there's an asterisk by the column name, which leads to this note:

    Columns marked with an asterisk (*) are populated only if you collect statistics on the table with the ANALYZE statement or the DBMS_STATS package.

    This means that unless you have gathered statistics on the table then this column will not have any data.

  2. Statistics gathered in 11g+ with the default estimate_percent, or with a 100% estimate, will return an accurate number for that point in time. But statistics gathered before 11g, or with a custom estimate_percent less than 100%, uses dynamic sampling and may be incorrect. If you gather 99.999% a single row may be missed, which in turn means that the answer you get is incorrect.

If your table is never updated then it is certainly possible to use ALL_TABLES.NUM_ROWS to find out the number of rows in a table. However, and it's a big however, if any process inserts or deletes rows from your table it will be at best a good approximation and depending on whether your database gathers statistics automatically could be horribly wrong.

Generally speaking, it is always better to actually count the number of rows in the table rather then relying on the system tables.

Objective-C implicit conversion loses integer precision 'NSUInteger' (aka 'unsigned long') to 'int' warning

Contrary to Martin's answer, casting to int (or ignoring the warning) isn't always safe even if you know your array doesn't have more than 2^31-1 elements. Not when compiling for 64-bit.

For example:

NSArray *array = @[@"a", @"b", @"c"];

int i = (int) [array indexOfObject:@"d"];
// indexOfObject returned NSNotFound, which is NSIntegerMax, which is LONG_MAX in 64 bit.
// We cast this to int and got -1.
// But -1 != NSNotFound. Trouble ahead!

if (i == NSNotFound) {
    // thought we'd get here, but we don't
    NSLog(@"it's not here");
}
else {
    // this is what actually happens
    NSLog(@"it's here: %d", i);

    // **** crash horribly ****
    NSLog(@"the object is %@", array[i]);
}

Changing tab bar item image and text color iOS

Try add it on AppDelegate.swift (inside application method):

UITabBar.appearance().tintColor = UIColor(red: 0/255.0, green: 0/255.0, blue: 0/255.0, alpha: 1.0)

// For WHITE color: 
UITabBar.appearance().tintColor = UIColor(red: 255/255.0, green: 255/255.0, blue: 255/255.0, alpha: 1.0)

Example:

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
    // Tab bar icon selected color
    UITabBar.appearance().tintColor = UIColor(red: 0/255.0, green: 0/255.0, blue: 0/255.0, alpha: 1.0)
    // For WHITE color: UITabBar.appearance().tintColor = UIColor(red: 255/255.0, green: 255/255.0, blue: 255/255.0, alpha: 1.0)
    return true
}

Example:

enter image description here

enter image description here

My english is so bad! I'm sorry! :-)

How to change the URI (URL) for a remote Git repository?

If you're using TortoiseGit then follow the below steps:

  1. Go to your local checkout folder and right click to go to TortoiseGit -> Settings
  2. In the left pane choose Git -> Remote
  3. In the right pane choose origin
  4. Now change the URL text box value to where ever your new remote repository is

Your branch and all your local commits will remain intact and you can keep working as you were before.

How to increase request timeout in IIS?

For AspNetCore, it looks like this:

<aspNetCore requestTimeout="00:20:00">

From here

TypeError: expected a character buffer object - while trying to save integer to textfile

from __future__ import with_statement
with open('file.txt','r+') as f:
    counter = str(int(f.read().strip())+1)
    f.seek(0)
    f.write(counter)

Garbage collector in Android

Generally speaking, in the presence of a garbage collector, it is never good practice to manually call the GC. A GC is organized around heuristic algorithms which work best when left to their own devices. Calling the GC manually often decreases performance.

Occasionally, in some relatively rare situations, one may find that a particular GC gets it wrong, and a manual call to the GC may then improves things, performance-wise. This is because it is not really possible to implement a "perfect" GC which will manage memory optimally in all cases. Such situations are hard to predict and depend on many subtle implementation details. The "good practice" is to let the GC run by itself; a manual call to the GC is the exception, which should be envisioned only after an actual performance issue has been duly witnessed.

Creating a Menu in Python

This should do it. You were missing a ) and you only need """ not 4 of them. Also you don't need a elif at the end.

ans=True
while ans:
    print("""
    1.Add a Student
    2.Delete a Student
    3.Look Up Student Record
    4.Exit/Quit
    """)
    ans=raw_input("What would you like to do? ")
    if ans=="1":
      print("\nStudent Added")
    elif ans=="2":
      print("\n Student Deleted")
    elif ans=="3":
      print("\n Student Record Found")
    elif ans=="4":
      print("\n Goodbye") 
      ans = None
    else:
       print("\n Not Valid Choice Try again")

How to obtain the query string from the current URL with JavaScript?

You can simply use URLSearchParams().

Lets see we have a page with url:

  • https://example.com/?product=1&category=game

On that page, you can get the query string using window.location.search and then extract them with URLSearchParams() class.

const params = new URLSearchParams(window.location.search)

console.log(params.get('product')
// 1

console.log(params.get('category')
// game

Another example using a dynamic url (not from window.location), you can extract the url using URL object.

const url = new URL('https://www.youtube.com/watch?v=6xJ27BtlM0c&ab_channel=FliteTest')

console.log(url.search)
// ?v=6xJ27BtlM0c&ab_channel=FliteTest

This is a simple working snippet:

_x000D_
_x000D_
const urlInput = document.querySelector('input[type=url]')
const keyInput = document.querySelector('input[name=key]')
const button = document.querySelector('button')
const outputDiv = document.querySelector('#output')

button.addEventListener('click', () => {
    const url = new URL(urlInput.value)
    const params = new URLSearchParams(url.search)
    output.innerHTML = params.get(keyInput.value)
})
_x000D_
div {
margin-bottom: 1rem;
}
_x000D_
<div>
  <label>URL</label> <br>
  <input type="url" value="https://www.youtube.com/watch?v=6xJ27BtlM0c&ab_channel=FliteTest">
</div>

<div>
  <label>Params key</label> <br>
  <input type="text" name="key" value="v">
</div>

<div>
  <button>Get Value</button>
</div>

<div id="output"></div>
_x000D_
_x000D_
_x000D_

Stopword removal with NLTK

There is an in-built stopword list in NLTK made up of 2,400 stopwords for 11 languages (Porter et al), see http://nltk.org/book/ch02.html

>>> from nltk import word_tokenize
>>> from nltk.corpus import stopwords
>>> stop = set(stopwords.words('english'))
>>> sentence = "this is a foo bar sentence"
>>> print([i for i in sentence.lower().split() if i not in stop])
['foo', 'bar', 'sentence']
>>> [i for i in word_tokenize(sentence.lower()) if i not in stop] 
['foo', 'bar', 'sentence']

I recommend looking at using tf-idf to remove stopwords, see Effects of Stemming on the term frequency?

Initializing a two dimensional std::vector

My c++ STL code to initialise 5*3 2-D vector with zero


#include <iostream>
using namespace std;
#include <vector>
int main()
{// if we wnt to initialise a 2 D vector with 0;

    vector<vector<int>> v1(5, vector<int>(3,0));

    for(int i=0;i<v1.size();i++) 
{
        for(int j=0;j<v1[i].size();j++)

           cout<<v1[i][j]<<" ";

            cout<<endl;
    }
}

The following artifacts could not be resolved: javax.jms:jms:jar:1.1

A check of ibliblio and java.net repositories reveal that jmx related jar is not present in either. I think you should manually download jms and install them locally as discussed here.

R: rJava package install failing

what I do is here:

  1. in /etc/apt/sources.list, add:

    deb http://ftp.de.debian.org/debian sid main

Note:the rjava should be latest version

2 run: sudo apt-get update sudo apt-get install r-cran-rjava

Once update the old version of rjava, then can install rhdfs_1.0.8.

Laravel 4: how to run a raw SQL?

The accepted way to rename a table in Laravel 4 is to use the Schema builder. So you would want to do:

Schema::rename('photos', 'images');

From http://laravel.com/docs/4.2/schema#creating-and-dropping-tables

If you really want to write out a raw SQL query yourself, you can always do:

DB::statement('alter table photos rename to images');

Note: Laravel's DB class also supports running raw SQL select, insert, update, and delete queries, like:

$users = DB::select('select id, name from users');

For more info, see http://laravel.com/docs/4.2/database#running-queries.

how to set ASPNETCORE_ENVIRONMENT to be considered for publishing an asp.net core application?

Option1:

To set the ASPNETCORE_ENVIRONMENT environment variable in windows,

Command line - setx ASPNETCORE_ENVIRONMENT "Development"

PowerShell - $Env:ASPNETCORE_ENVIRONMENT = "Development"

For other OS refer this - https://docs.microsoft.com/en-us/aspnet/core/fundamentals/environments

Option2:

If you want to set ASPNETCORE_ENVIRONMENT using web.config then add aspNetCore like this-

<configuration>
  <!--
    Configure your application settings in appsettings.json. Learn more at http://go.microsoft.com/fwlink/?LinkId=786380
  -->
  <system.webServer>
    <handlers>
      <add name="aspNetCore" path="*" verb="*" modules="AspNetCoreModule" resourceType="Unspecified" />
    </handlers>
    <aspNetCore processPath=".\MyApplication.exe" arguments="" stdoutLogEnabled="false" stdoutLogFile=".\logs\stdout" forwardWindowsAuthToken="false">
      <environmentVariables>
        <environmentVariable name="ASPNETCORE_ENVIRONMENT" value="Development" />
      </environmentVariables>
    </aspNetCore>
  </system.webServer>
</configuration>

Is module __file__ attribute absolute or relative?

With the help of the of Guido mail provided by @kindall, we can understand the standard import process as trying to find the module in each member of sys.path, and file as the result of this lookup (more details in PyMOTW Modules and Imports.). So if the module is located in an absolute path in sys.path the result is absolute, but if it is located in a relative path in sys.path the result is relative.

Now the site.py startup file takes care of delivering only absolute path in sys.path, except the initial '', so if you don't change it by other means than setting the PYTHONPATH (whose path are also made absolute, before prefixing sys.path), you will get always an absolute path, but when the module is accessed through the current directory.

Now if you trick sys.path in a funny way you can get anything.

As example if you have a sample module foo.py in /tmp/ with the code:

import sys
print(sys.path)
print (__file__)

If you go in /tmp you get:

>>> import foo
['', '/tmp', '/usr/lib/python3.3', ...]
./foo.py

When in in /home/user, if you add /tmp your PYTHONPATH you get:

>>> import foo
['', '/tmp', '/usr/lib/python3.3', ...]
/tmp/foo.py

Even if you add ../../tmp, it will be normalized and the result is the same.

But if instead of using PYTHONPATH you use directly some funny path you get a result as funny as the cause.

>>> import sys
>>> sys.path.append('../../tmp')
>>> import foo
['', '/usr/lib/python3.3', .... , '../../tmp']
../../tmp/foo.py

Guido explains in the above cited thread, why python do not try to transform all entries in absolute paths:

we don't want to have to call getpwd() on every import .... getpwd() is relatively slow and can sometimes fail outright,

So your path is used as it is.

Create two blank lines in Markdown

I test on a lot of Markdown implementations. The non-breaking space ASCII character &nbsp; (followed by a blank line) would give a blank line. Repeating this pair would do the job. So far I haven't failed any.

 

 

 

For example:  

 

 

Hello

 

 

 

 

 

 

world!

 

 

Side-by-side list items as icons within a div (css)

I would recommend that you use display: inline;. float is screwed up in IE. Here is an example of how I would approach it:

<ul class="side-by-side">
  <li>item 1<li>
  <li>item 2<li>
  <li>item 3<li>
</ul>

and here's the css:

.side-by-side {
  width: 100%;
  border: 1px solid black;

}
.side-by-side li {
  display: inline;
}

Also, if you use floats the ul will not wrap around the li's and will instead have a hight of 0 in this example:

.side-by-side li {
  float: left;
}

Is SMTP based on TCP or UDP?

Seems the SMTP as internet standard uses only reliable Transport protocol. RFC821 has TCP, NCP, NITS as examples!

Volatile vs Static in Java

In simple terms,

  1. static : static variables are associated with the class, rather than with any object. Every instance of the class shares a class variable, which is in one fixed location in memory

  2. volatile: This keyword is applicable to both class and instance variables.

Using volatile variables reduces the risk of memory consistency errors, because any write to a volatile variable establishes a happens-before relationship with subsequent reads of that same variable. This means that changes to a volatile variable are always visible to other threads

Have a look at this article by Javin Paul to understand volatile variables in a better way.

enter image description here

In absence of volatile keyword, the value of variable in each thread's stack may be different. By making the variable as volatile, all threads will get same value in their working memory and memory consistency errors have been avoided.

Here the term variable can be either static (class) variable or instance (object) variable.

Regarding your query :

Anyway a static variable value is also going to be one value for all threads, then why should we go for volatile?

If I need instance variable in my application, I can't use static variable. Even in case of static variable, consistency is not guaranteed due to Thread cache as shown in the diagram.

Using volatile variables reduces the risk of memory consistency errors, because any write to a volatile variable establishes a happens-before relationship with subsequent reads of that same variable. This means that changes to a volatile variable are always visible to other threads.

What's more, it also means that when a thread reads a volatile variable, it sees not just the latest change to the volatile, but also the side effects of the code that led up the change => memory consistency errors are still possible with volatile variables. To avoid side effects, you have to use synchronized variables. But there is a better solution in java.

Using simple atomic variable access is more efficient than accessing these variables through synchronized code

Some of the classes in the java.util.concurrent package provide atomic methods that do not rely on synchronization.

Refer to this high level concurrency control article for more details.

Especially have a look at Atomic variables.

Related SE questions:

Volatile Vs Atomic

Volatile boolean vs AtomicBoolean

Difference between volatile and synchronized in Java

Create a git patch from the uncommitted changes in the current working directory

I like:

git format-patch HEAD~<N>

where <N> is number of last commits to save as patches.

The details how to use the command are in the DOC

UPD
Here you can find how to apply them then.

UPD For those who did not get the idea of format-patch
Add alias:

git config --global alias.make-patch '!bash -c "cd ${GIT_PREFIX};git add .;git commit -m ''uncommited''; git format-patch HEAD~1; git reset HEAD~1"'

Then at any directory of your project repository run:

git make-patch

This command will create 0001-uncommited.patch at your current directory. Patch will contain all the changes and untracked files that are visible to next command:

git status .

Mean per group in a data.frame

A third great alternative is using the package data.table, which also has the class data.frame, but operations like you are looking for are computed much faster.

library(data.table)
mydt <- structure(list(Name = c("Aira", "Aira", "Aira", "Ben", "Ben", "Ben", "Cat", "Cat", "Cat"), Month = c(1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L), Rate1 = c(15.6396600443877, 2.15649279424609, 6.24692918928743, 2.37658797276116, 34.7500663272292, 3.28750138697048, 29.3265553981065, 17.9821839334431, 10.8639802575958), Rate2 = c(17.1680489538369, 5.84231656330206, 8.54330866437461, 5.88415184986176, 3.02064294862551, 17.2053351400752, 16.9552950199166, 2.56058000170089, 15.7496228048122)), .Names = c("Name", "Month", "Rate1", "Rate2"), row.names = c(NA, -9L), class = c("data.table", "data.frame"))

Now to take the mean of Rate1 and Rate2 for all 3 months, for each person (Name): First, decide which columns you want to take the mean of

colstoavg <- names(mydt)[3:4]

Now we use lapply to take the mean over the columns we want to avg (colstoavg)

mydt.mean <- mydt[,lapply(.SD,mean,na.rm=TRUE),by=Name,.SDcols=colstoavg]

 mydt.mean
   Name     Rate1     Rate2
1: Aira  8.014361 10.517891
2:  Ben 13.471385  8.703377
3:  Cat 19.390907 11.755166

jQuery to remove an option from drop down list, given option's text/value

Many people had difficulty in using this keyword when we have iteration of Drop-downs with same elements but different values or say as Multi line data in USER INTERFACE. : Here is the code snippet : $(this).find('option[value=yourvalue]');

Hope you got this.

How to place object files in separate subdirectory

None of these answers seemed simple enough - the crux of the problem is not having to rebuild:

makefile

OBJDIR=out
VPATH=$(OBJDIR)

# make will look in VPATH to see if the target needs to be rebuilt
test: moo
    touch $(OBJDIR)/$@

example use

touch moo
# creates out/test
make test
# doesn't update out/test
make test
# will now update test
touch moo
make test

How to set environment variables in Jenkins?

This is the snippet to store environment variable and access it.

node {
   withEnv(["ENABLE_TESTS=true", "DISABLE_SQL=false"]) {
      stage('Select Jenkinsfile') {
          echo "Enable test?: ${env.DEVOPS_SKIP_TESTS}
          customStep script: this
      }
   }
}

Note: The value of environment variable is coming as a String. If you want to use it as a boolean then you have to parse it using Boolean.parse(env.DISABLE_SQL).

Unix epoch time to Java Date object

To convert seconds time stamp to millisecond time stamp. You could use the TimeUnit API and neat like this.

long milliSecondTimeStamp = MILLISECONDS.convert(secondsTimeStamp, SECONDS)

ASP.NET MVC Global Variables

public static class GlobalVariables
{
    // readonly variable
    public static string Foo
    {
        get
        {
            return "foo";
        }
    }

    // read-write variable
    public static string Bar
    {
        get
        {
            return HttpContext.Current.Application["Bar"] as string;
        }
        set
        {
            HttpContext.Current.Application["Bar"] = value;
        }
    }
}

Any way to make plot points in scatterplot more transparent in R?

When creating the colors, you may use rgb and set its alpha argument:

plot(1:10, col = rgb(red = 1, green = 0, blue = 0, alpha = 0.5),
     pch = 16, cex = 4)
points((1:10) + 0.4, col = rgb(red = 0, green = 0, blue = 1, alpha = 0.5),
       pch = 16, cex = 4)

enter image description here

Please see ?rgb for details.

What is the height of iPhone's onscreen keyboard?

I created this table which contains both the heights of iPhone and iPad keyboards, both for landscape and portrait mode, both with the toolbar on and off.

I even explained how you can use these dimensions in your code here.

Note that you should only use these dimensions if you need to know the keyboard's dimension before you layout the view. Otherwise the solutions from the other answers work better.

enter image description here

Split (explode) pandas dataframe string entry to separate rows

upgraded MaxU's answer with MultiIndex support

def explode(df, lst_cols, fill_value='', preserve_index=False):
    """
    usage:
        In [134]: df
        Out[134]:
           aaa  myid        num          text
        0   10     1  [1, 2, 3]  [aa, bb, cc]
        1   11     2         []            []
        2   12     3     [1, 2]      [cc, dd]
        3   13     4         []            []

        In [135]: explode(df, ['num','text'], fill_value='')
        Out[135]:
           aaa  myid num text
        0   10     1   1   aa
        1   10     1   2   bb
        2   10     1   3   cc
        3   11     2
        4   12     3   1   cc
        5   12     3   2   dd
        6   13     4
    """
    # make sure `lst_cols` is list-alike
    if (lst_cols is not None
        and len(lst_cols) > 0
        and not isinstance(lst_cols, (list, tuple, np.ndarray, pd.Series))):
        lst_cols = [lst_cols]
    # all columns except `lst_cols`
    idx_cols = df.columns.difference(lst_cols)
    # calculate lengths of lists
    lens = df[lst_cols[0]].str.len()
    # preserve original index values    
    idx = np.repeat(df.index.values, lens)
    res = (pd.DataFrame({
                col:np.repeat(df[col].values, lens)
                for col in idx_cols},
                index=idx)
             .assign(**{col:np.concatenate(df.loc[lens>0, col].values)
                            for col in lst_cols}))
    # append those rows that have empty lists
    if (lens == 0).any():
        # at least one list in cells is empty
        res = (res.append(df.loc[lens==0, idx_cols], sort=False)
                  .fillna(fill_value))
    # revert the original index order
    res = res.sort_index()
    # reset index if requested
    if not preserve_index:        
        res = res.reset_index(drop=True)

    # if original index is MultiIndex build the dataframe from the multiindex
    # create "exploded" DF
    if isinstance(df.index, pd.MultiIndex):
        res = res.reindex(
            index=pd.MultiIndex.from_tuples(
                res.index,
                names=['number', 'color']
            )
    )
    return res

What is the simplest C# function to parse a JSON string into an object?

I think this is what you want:

JavaScriptSerializer JSS = new JavaScriptSerializer();
T obj = JSS.Deserialize<T>(String);

IN Clause with NULL or IS NULL

An in statement will be parsed identically to field=val1 or field=val2 or field=val3. Putting a null in there will boil down to field=null which won't work.

(Comment by Marc B)

I would do this for clairity

SELECT *
FROM tbl_name
WHERE 
(id_field IN ('value1', 'value2', 'value3') OR id_field IS NULL)

Active Directory LDAP Query by sAMAccountName and Domain

"Domain" is not a property of an LDAP object. It is more like the name of the database the object is stored in.

So you have to connect to the right database (in LDAP terms: "bind to the domain/directory server") in order to perform a search in that database.

Once you bound successfully, your query in it's current shape is all you need.

BTW: Choosing "ObjectCategory=Person" over "ObjectClass=user" was a good decision. In AD, the former is an "indexed property" with excellent performance, the latter is not indexed and a tad slower.

Calculating Covariance with Python and Numpy

When a and b are 1-dimensional sequences, numpy.cov(a,b)[0][1] is equivalent to your cov(a,b).

The 2x2 array returned by np.cov(a,b) has elements equal to

cov(a,a)  cov(a,b)

cov(a,b)  cov(b,b)

(where, again, cov is the function you defined above.)

Split string based on a regular expression

The str.split method will automatically remove all white space between items:

>>> str1 = "a    b     c      d"
>>> str1.split()
['a', 'b', 'c', 'd']

Docs are here: http://docs.python.org/library/stdtypes.html#str.split

Why Java Calendar set(int year, int month, int date) not returning correct date?

Months in Calendar object start from 0

0 = January = Calendar.JANUARY
1 = february = Calendar.FEBRUARY

IE8 css selector

\9 doesn’t work with font-family, instead you’d need to use “\0/ !important” as Chris mentioned above, for example:

p { font-family: Arial \0/ !important; }

How to read text file in JavaScript

This can be done quite easily using javascript XMLHttpRequest() class (AJAX):

function FileHelper()

{
    FileHelper.readStringFromFileAtPath = function(pathOfFileToReadFrom)
    {
        var request = new XMLHttpRequest();
        request.open("GET", pathOfFileToReadFrom, false);
        request.send(null);
        var returnValue = request.responseText;

        return returnValue;
    }
}

...

var text = FileHelper.readStringFromFileAtPath ( "mytext.txt" );

How do I execute external program within C code in linux with arguments?

Here's the way to extend to variable args when you don't have the args hard coded (although they are still technically hard coded in this example, but should be easy to figure out how to extend...):

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

int argcount = 3;
const char* args[] = {"1", "2", "3"};
const char* binary_name = "mybinaryname";
char myoutput_array[5000];

sprintf(myoutput_array, "%s", binary_name);
for(int i = 0; i < argcount; ++i)
{
    strcat(myoutput_array, " ");
    strcat(myoutput_array, args[i]);
}
system(myoutput_array);

Changing variable names with Python for loops

Definitely should use a dict using the "group" + str(i) key as described in the accepted solution but I wanted to share a solution using exec. Its a way to parse strings into commands & execute them dynamically. It would allow to create these scalar variable names as per your requirement instead of using a dict. This might help in regards what not to do, and just because you can doesn't mean you should. Its a good solution only if using scalar variables is a hard requirement:

l = locals()
for i in xrange(3):
    exec("group" + str(i) + "= self.getGroup(selected, header + i)")

Another example where this could work using a Django model example. The exec alternative solution is commented out and the better way of handling such a case using the dict attribute makes more sense:

Class A(models.Model):

    ....

    def __getitem__(self, item):  # a.__getitem__('id')
        #exec("attrb = self." + item)
        #return attrb
        return self.__dict__[item]

It might make more sense to extend from a dictionary in the first place to get setattr and getattr functions.

A situation which involves parsing, for example generating & executing python commands dynamically, exec is what you want :) More on exec here.

Function to close the window in Tkinter

def exit(self):
    self.frame.destroy()
exit_btn=Button(self.frame,text='Exit',command=self.exit,activebackground='grey',activeforeground='#AB78F1',bg='#58F0AB',highlightcolor='red',padx='10px',pady='3px')
exit_btn.place(relx=0.45,rely=0.35)

This worked for me to destroy my Tkinter frame on clicking the exit button.

How to select the row with the maximum value in each group

I wasn't sure what you wanted to do about the Event column, but if you want to keep that as well, how about

isIDmax <- with(dd, ave(Value, ID, FUN=function(x) seq_along(x)==which.max(x)))==1
group[isIDmax, ]

#   ID Value Event
# 3  1     5     2
# 7  2    17     2
# 9  3     5     2

Here we use ave to look at the "Value" column for each "ID". Then we determine which value is the maximal and then turn that into a logical vector we can use to subset the original data.frame.

Adding a column to an existing table in a Rails migration

You also can use special change_table method in the migration for adding new columns:

change_table(:users) do |t|
  t.column :email, :string
end

How to clear jQuery validation error messages?

I tested with:

$("div.error").remove();
$(".error").removeClass("error");

It will be ok, when you need to validate it again.

Does Typescript support the ?. operator? (And, what's it called?)

Operator ?. is not supported in TypeScript version 2.0.

So I use the following function:

export function o<T>(someObject: T, defaultValue: T = {} as T) : T {
    if (typeof someObject === 'undefined' || someObject === null)
        return defaultValue;
    else
        return someObject;
}

the usage looks like this:

o(o(o(test).prop1).prop2

plus, you can set a default value:

o(o(o(o(test).prop1).prop2, "none")

It works really well with IntelliSense in Visual Studio.

How do I activate a Spring Boot profile when running from IntelliJ?

Spring Boot seems had changed the way of reading the VM options as it evolves. Here's some way to try when you launch an application in Intellij and want to active some profile:

1. Change VM options

Open "Edit configuration" in "Run", and in "VM options", add: -Dspring.profiles.active=local

It actually works with one project of mine with Spring Boot v2.0.3.RELEASE and Spring v5.0.7.RELEASE, but not with another project with Spring Boot v2.1.1.RELEASE and Spring v5.1.3.RELEASE.

Also, when running with Maven or JAR, people mentioned this:

mvn spring-boot:run -Drun.profiles=dev

or

java -jar -Dspring.profiles.active=dev XXX.jar

(See here: how to use Spring Boot profiles)

2. Passing JVM args

It is mentioned somewhere, that Spring changes the way of launching the process of applications if you specify some JVM options; it forks another process and will not pass the arg it received so this does not work. The only way to pass args to it, is:

mvn spring-boot:run -Dspring-boot.run.jvmArguments="..."

Again, this is for Maven. https://docs.spring.io/spring-boot/docs/current/maven-plugin/examples/run-debug.html

3. Setting (application) env var

What works for me for the second project, was setting the environment variable, as mentioned in some answer above: "Edit configuration" - "Environment variable", and:

SPRING_PROFILES_ACTIVE=local

C# int to enum conversion

Casting should be enough. If you're using C# 3.0 you can make a handy extension method to parse enum values:

public static TEnum ToEnum<TInput, TEnum>(this TInput value)
{
    Type type = typeof(TEnum);

    if (value == default(TInput))
    {
        throw new ArgumentException("Value is null or empty.", "value");
    }

    if (!type.IsEnum)
    {
        throw new ArgumentException("Enum expected.", "TEnum");
    }

    return (TEnum)Enum.Parse(type, value.ToString(), true);
}

Reading a .txt file using Scanner class in Java

You have to put file extension here

File file = new File("10_Random.txt");

get number of columns of a particular row in given excel using Java

/** Count max number of nonempty cells in sheet rows */
private int getColumnsCount(XSSFSheet xssfSheet) {
    int result = 0;
    Iterator<Row> rowIterator = xssfSheet.iterator();
    while (rowIterator.hasNext()) {
        Row row = rowIterator.next();
        List<Cell> cells = new ArrayList<>();
        Iterator<Cell> cellIterator = row.cellIterator();
        while (cellIterator.hasNext()) {
            cells.add(cellIterator.next());
        }
        for (int i = cells.size(); i >= 0; i--) {
            Cell cell = cells.get(i-1);
            if (cell.toString().trim().isEmpty()) {
                cells.remove(i-1);
            } else {
                result = cells.size() > result ? cells.size() : result;
                break;
            }
        }
    }
    return result;
}

Servlet Mapping using web.xml

It allows servlets to have multiple servlet mappings:

<servlet>
    <servlet-name>Servlet1</servlet-name>
    <servlet-path>foo.Servlet</servlet-path>
</servlet>
<servlet-mapping>
    <servlet-name>Servlet1</servlet-name>
    <url-pattern>/enroll</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>Servlet1</servlet-name>
    <url-pattern>/pay</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>Servlet1</servlet-name>
    <url-pattern>/bill</url-pattern>
</servlet-mapping>

It allows filters to be mapped on the particular servlet:

<filter-mapping>
    <filter-name>Filter1</filter-name>
    <servlet-name>Servlet1</servlet-name>
</filter-mapping>

Your proposal would support neither of them. Note that the web.xml is read and parsed only once during application's startup, not on every HTTP request as you seem to think.

Since Servlet 3.0, there's the @WebServlet annotation which minimizes this boilerplate:

@WebServlet("/enroll")
public class Servlet1 extends HttpServlet {

See also:

How to store array or multiple values in one column

You have a couple of questions here, so I'll address them separately:

I need to store a number of selected items in one field in a database

My general rule is: don't. This is something which all but requires a second table (or third) with a foreign key. Sure, it may seem easier now, but what if the use case comes along where you need to actually query for those items individually? It also means that you have more options for lazy instantiation and you have a more consistent experience across multiple frameworks/languages. Further, you are less likely to have connection timeout issues (30,000 characters is a lot).

You mentioned that you were thinking about using ENUM. Are these values fixed? Do you know them ahead of time? If so this would be my structure:

Base table (what you have now):

| id primary_key sequence
| -- other columns here.

Items table:

| id primary_key sequence
| descript VARCHAR(30) UNIQUE

Map table:

| base_id  bigint
| items_id bigint

Map table would have foreign keys so base_id maps to Base table, and items_id would map to the items table.

And if you'd like an easy way to retrieve this from a DB, then create a view which does the joins. You can even create insert and update rules so that you're practically only dealing with one table.

What format should I use store the data?

If you have to do something like this, why not just use a character delineated string? It will take less processing power than a CSV, XML, or JSON, and it will be shorter.

What column type should I use store the data?

Personally, I would use TEXT. It does not sound like you'd gain much by making this a BLOB, and TEXT, in my experience, is easier to read if you're using some form of IDE.

exception in thread 'main' java.lang.NoClassDefFoundError:

I had this error because I had my files within a package. So my foo package I had to call like:

java foo.HelloWorld

An unhandled exception was generated during the execution of the current web request

In my case, I created a new project and when I ran it the first time, it gave me the following error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

So my solution was to go to the Package Manager Console inside the Visual Studio and run:Update-Package

Problem solved!!

Get the short Git version hash

Try this:

git rev-parse --short HEAD

The command git rev-parse can do a remarkable number of different things, so you'd need to go through the documentation very carefully to spot that though.

File.Move Does Not Work - File Already Exists

If you don't have the option to delete the already existing file in the new location, but still need to move and delete from the original location, this renaming trick might work:

string newFileLocation = @"c:\test\Test\SomeFile.txt";

while (File.Exists(newFileLocation)) {
    newFileLocation = newFileLocation.Split('.')[0] + "_copy." + newFileLocation.Split('.')[1];
}
File.Move(@"c:\test\SomeFile.txt", newFileLocation);

This assumes the only '.' in the file name is before the extension. It splits the file in two before the extension, attaches "_copy." in between. This lets you move the file, but creates a copy if the file already exists or a copy of the copy already exists, or a copy of the copy of the copy exists... ;)

Vue.js redirection to another page

just use:

window.location.href = "http://siwei.me"

Don't use vue-router, otherwise you will be redirected to "http://yoursite.com/#!/http://siwei.me"

my environment: node 6.2.1, vue 1.0.21, Ubuntu.

Does Python have a package/module management system?

And just to provide a contrast, there's also pip.

Cache an HTTP 'Get' service response in AngularJS?

Check out the library angular-cache if you like $http's built-in caching but want more control. You can use it to seamlessly augment $http cache with time-to-live, periodic purges, and the option of persisting the cache to localStorage so that it's available across sessions.

FWIW, it also provides tools and patterns for making your cache into a more dynamic sort of data-store that you can interact with as POJO's, rather than just the default JSON strings. Can't comment on the utility of that option as yet.

(Then, on top of that, related library angular-data is sort of a replacement for $resource and/or Restangular, and is dependent upon angular-cache.)

How to select the comparison of two columns as one column in Oracle

select column1, coulumn2, case when colum1=column2 then 'true' else 'false' end from table;

HTH

Is the server running on host "localhost" (::1) and accepting TCP/IP connections on port 5432?

I resolved the issue via this command

pg_ctl -D /usr/local/var/postgres start

At times, you might get this error

pg_ctl: another server might be running; trying to start server anyway

So, try running the following command and then run the first command given above.

pg_ctl -D /usr/local/var/postgres stop

Create a OpenSSL certificate on Windows

If you're on windows and using apache, maybe via WAMP or the Drupal stack installer, you can additionally download the git for windows package, which includes many useful linux command line tools, one of which is openssl.

The following command creates the self signed certificate and key needed for apache and works fine in windows:

openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout privatekey.key -out certificate.crt

Is Java "pass-by-reference" or "pass-by-value"?

In my opinion, "pass by value" is a terrible way to singularly describe two similar but different events. I guess they should have asked me first.

With primitives we are passing the actual value of the primitive into the method (or constructor), be it the integer "5", the character "c", or what have you. That actual value then becomes its own local primitive. But with objects, all we are doing is giving the same object an additional reference (a local reference), so that we now have two references pointing to the same object.

I hope this simple explanation helps.

How to create a directory using Ansible

If you want to create directory in windows:

  • name: Create directory structure
    win_file:
    path: C:\Temp\folder\subfolder>
    state: directory

How to align entire html body to the center?

EDIT

As of today with flexbox, you could

body {
  display:flex; flex-direction:column; justify-content:center;
  min-height:100vh;
}

PREVIOUS ANSWER

html, body {height:100%;}
html {display:table; width:100%;}
body {display:table-cell; text-align:center; vertical-align:middle;}

An error has occured. Please see log file - eclipse juno

Deleting metadata folder might not work in this case. Or eclipse -clean command. Or reinstall eclipse might not solve this.

Instead try deleting other java versions you might have in your machine.

Check what you have right now using this:

/usr/libexec/java_home -V

Delete other java versions which you don't want, following below command:

sudo rm -rf /System/Library/Java/JavaVirtualMachines/java-version.jdk

This should resolve your issue.

How do I import a namespace in Razor View Page?

"using MyNamespace" works in MVC3 RTM. Hope this helps.

How to configure the web.config to allow requests of any length

I had to add [AllowAnonymous] to the ActionResult functions in my login page because the user was not authenticated yet.

Pandas index column title or name

You can use rename_axis, for removing set to None:

d = {'Index Title': ['Apples', 'Oranges', 'Puppies', 'Ducks'],'Column 1': [1.0, 2.0, 3.0, 4.0]}
df = pd.DataFrame(d).set_index('Index Title')
print (df)
             Column 1
Index Title          
Apples            1.0
Oranges           2.0
Puppies           3.0
Ducks             4.0

print (df.index.name)
Index Title

print (df.columns.name)
None

The new functionality works well in method chains.

df = df.rename_axis('foo')
print (df)
         Column 1
foo              
Apples        1.0
Oranges       2.0
Puppies       3.0
Ducks         4.0

You can also rename column names with parameter axis:

d = {'Index Title': ['Apples', 'Oranges', 'Puppies', 'Ducks'],'Column 1': [1.0, 2.0, 3.0, 4.0]}
df = pd.DataFrame(d).set_index('Index Title').rename_axis('Col Name', axis=1)
print (df)
Col Name     Column 1
Index Title          
Apples            1.0
Oranges           2.0
Puppies           3.0
Ducks             4.0

print (df.index.name)
Index Title

print (df.columns.name)
Col Name
print df.rename_axis('foo').rename_axis("bar", axis="columns")
bar      Column 1
foo              
Apples        1.0
Oranges       2.0
Puppies       3.0
Ducks         4.0

print df.rename_axis('foo').rename_axis("bar", axis=1)
bar      Column 1
foo              
Apples        1.0
Oranges       2.0
Puppies       3.0
Ducks         4.0

From version pandas 0.24.0+ is possible use parameter index and columns:

df = df.rename_axis(index='foo', columns="bar")
print (df)
bar      Column 1
foo              
Apples        1.0
Oranges       2.0
Puppies       3.0
Ducks         4.0

Removing index and columns names means set it to None:

df = df.rename_axis(index=None, columns=None)
print (df)
         Column 1
Apples        1.0
Oranges       2.0
Puppies       3.0
Ducks         4.0

If MultiIndex in index only:

mux = pd.MultiIndex.from_arrays([['Apples', 'Oranges', 'Puppies', 'Ducks'],
                                  list('abcd')], 
                                  names=['index name 1','index name 1'])


df = pd.DataFrame(np.random.randint(10, size=(4,6)), 
                  index=mux, 
                  columns=list('ABCDEF')).rename_axis('col name', axis=1)
print (df)
col name                   A  B  C  D  E  F
index name 1 index name 1                  
Apples       a             5  4  0  5  2  2
Oranges      b             5  8  2  5  9  9
Puppies      c             7  6  0  7  8  3
Ducks        d             6  5  0  1  6  0

print (df.index.name)
None

print (df.columns.name)
col name

print (df.index.names)
['index name 1', 'index name 1']

print (df.columns.names)
['col name']

df1 = df.rename_axis(('foo','bar'))
print (df1)
col name     A  B  C  D  E  F
foo     bar                  
Apples  a    5  4  0  5  2  2
Oranges b    5  8  2  5  9  9
Puppies c    7  6  0  7  8  3
Ducks   d    6  5  0  1  6  0

df2 = df.rename_axis('baz', axis=1)
print (df2)
baz                        A  B  C  D  E  F
index name 1 index name 1                  
Apples       a             5  4  0  5  2  2
Oranges      b             5  8  2  5  9  9
Puppies      c             7  6  0  7  8  3
Ducks        d             6  5  0  1  6  0

df2 = df.rename_axis(index=('foo','bar'), columns='baz')
print (df2)
baz          A  B  C  D  E  F
foo     bar                  
Apples  a    5  4  0  5  2  2
Oranges b    5  8  2  5  9  9
Puppies c    7  6  0  7  8  3
Ducks   d    6  5  0  1  6  0

Removing index and columns names means set it to None:

df2 = df.rename_axis(index=(None,None), columns=None)
print (df2)

           A  B  C  D  E  F
Apples  a  6  9  9  5  4  6
Oranges b  2  6  7  4  3  5
Puppies c  6  3  6  3  5  1
Ducks   d  4  9  1  3  0  5

For MultiIndex in index and columns is necessary working with .names instead .name and set by list or tuples:

mux1 = pd.MultiIndex.from_arrays([['Apples', 'Oranges', 'Puppies', 'Ducks'],
                                  list('abcd')], 
                                  names=['index name 1','index name 1'])


mux2 = pd.MultiIndex.from_product([list('ABC'),
                                  list('XY')], 
                                  names=['col name 1','col name 2'])

df = pd.DataFrame(np.random.randint(10, size=(4,6)), index=mux1, columns=mux2)
print (df)
col name 1                 A     B     C   
col name 2                 X  Y  X  Y  X  Y
index name 1 index name 1                  
Apples       a             2  9  4  7  0  3
Oranges      b             9  0  6  0  9  4
Puppies      c             2  4  6  1  4  4
Ducks        d             6  6  7  1  2  8

Plural is necessary for check/set values:

print (df.index.name)
None

print (df.columns.name)
None

print (df.index.names)
['index name 1', 'index name 1']

print (df.columns.names)
['col name 1', 'col name 2']

df1 = df.rename_axis(('foo','bar'))
print (df1)
col name 1   A     B     C   
col name 2   X  Y  X  Y  X  Y
foo     bar                  
Apples  a    2  9  4  7  0  3
Oranges b    9  0  6  0  9  4
Puppies c    2  4  6  1  4  4
Ducks   d    6  6  7  1  2  8

df2 = df.rename_axis(('baz','bak'), axis=1)
print (df2)
baz                        A     B     C   
bak                        X  Y  X  Y  X  Y
index name 1 index name 1                  
Apples       a             2  9  4  7  0  3
Oranges      b             9  0  6  0  9  4
Puppies      c             2  4  6  1  4  4
Ducks        d             6  6  7  1  2  8

df2 = df.rename_axis(index=('foo','bar'), columns=('baz','bak'))
print (df2)
baz          A     B     C   
bak          X  Y  X  Y  X  Y
foo     bar                  
Apples  a    2  9  4  7  0  3
Oranges b    9  0  6  0  9  4
Puppies c    2  4  6  1  4  4
Ducks   d    6  6  7  1  2  8

Removing index and columns names means set it to None:

df2 = df.rename_axis(index=(None,None), columns=(None,None))
print (df2)

           A     B     C   
           X  Y  X  Y  X  Y
Apples  a  2  0  2  5  2  0
Oranges b  1  7  5  5  4  8
Puppies c  2  4  6  3  6  5
Ducks   d  9  6  3  9  7  0

And @Jeff solution:

df.index.names = ['foo','bar']
df.columns.names = ['baz','bak']
print (df)

baz          A     B     C   
bak          X  Y  X  Y  X  Y
foo     bar                  
Apples  a    3  4  7  3  3  3
Oranges b    1  2  5  8  1  0
Puppies c    9  6  3  9  6  3
Ducks   d    3  2  1  0  1  0

How do I access an access array item by index in handlebars?

If you want to use dynamic variables

This won't work:

{{#each obj[key]}}
...
{{/each}}

You need to do:

{{#each (lookup obj key)}}
...
{{/each}}

see handlebars lookup helper and handlebars subexpressions.

How to convert time milliseconds to hours, min, sec format in JavaScript?

If you're using typescript, this could be a good thing for you

enum ETime {
  Seconds = 1000,
  Minutes = 60000,
  Hours = 3600000,
  SecInMin = 60,
  MinInHours = 60,
  HoursMod = 24,
  timeMin = 10,
}

interface ITime {
  millis: number
  modulo: number
}

const Times = {
  seconds: {
    millis: ETime.Seconds,
    modulo: ETime.SecInMin,
  },
  minutes: {
    millis: ETime.Minutes,
    modulo: ETime.MinInHours,
  },
  hours: {
    millis: ETime.Hours,
    modulo: ETime.HoursMod,
  },
}

const dots: string = ":"

const msToTime = (duration: number, needHours: boolean = true): string => {
  const getCorrectTime = (divider: ITime): string => {
    const timeStr: number = Math.floor(
      (duration / divider.millis) % divider.modulo,
    )

    return timeStr < ETime.timeMin ? "0" + timeStr : String(timeStr)
  }

  return (
    (needHours ? getCorrectTime(Times.hours) + dots : "") +
    getCorrectTime(Times.minutes) +
    dots +
    getCorrectTime(Times.seconds)
  )
}

R numbers from 1 to 100

If you need the construct for a quick example to play with, use the : operator.

But if you are creating a vector/range of numbers dynamically, then use seq() instead.

Let's say you are creating the vector/range of numbers from a to b with a:b, and you expect it to be an increasing series. Then, if b is evaluated to be less than a, you will get a decreasing sequence but you will never be notified about it, and your program will continue to execute with the wrong kind of input.

In this case, if you use seq(), you can set the sign of the by argument to match the direction of your sequence, and an error will be raised if they do not match. For example,

seq(a, b, -1)

will raise an error for a=2, b=6, because the coder expected a decreasing sequence.

How to find patterns across multiple lines using grep?

Here is a solution inspired by this answer:

  • if 'abc' and 'efg' can be on the same line:

      grep -zl 'abc.*efg' <your list of files>
    
  • if 'abc' and 'efg' must be on different lines:

      grep -Pzl '(?s)abc.*\n.*efg' <your list of files>
    

Params:

  • -P Use perl compatible regular expressions (PCRE).

  • -z Treat the input as a set of lines, each terminated by a zero byte instead of a newline. i.e. grep treats the input as a one big line.

  • -l list matching filenames only.

  • (?s) activate PCRE_DOTALL, which means that '.' finds any character or newline.

Accessing Arrays inside Arrays In PHP

Regarding your code: It's slightly hard to read... If you want to try to view it all in a php array format, just print_r it. This might help:

<?php
$a =
array(  

  'languages' =>    

  array (   

  76 =>      

 array (       'id' => '76',       'tag' => 'Deutsch',     ),   ),    'targets' =>    
 array (     81 =>      
 array (       'id' => '81',       'tag' => 'Deutschland',     ),   ),    'tags' =>    
 array (     7866 =>      
 array (       'id' => '7866',       'tag' => 'automobile',     ),     17800 =>      
 array (       'id' => '17800',       'tag' => 'seat leon',     ),     17801 =>      
 array (       'id' => '17801',       'tag' => 'seat leon cupra',     ),   ),   
'inactiveTags' =>    
 array (     195 =>      
 array (       'id' => '195',       'tag' => 'auto',     ),     17804 =>      
 array (       'id' => '17804',       'tag' => 'coupès',     ),     17805 =>      
 array (       'id' => '17805',       'tag' => 'fahrdynamik',     ),     901 =>      
 array (       'id' => '901',       'tag' => 'fahrzeuge',     ),     17802 =>      
 array (       'id' => '17802',       'tag' => 'günstige neuwagen',     ),     1991 =>      
 array (       'id' => '1991',       'tag' => 'motorsport',     ),     2154 =>      
 array (       'id' => '2154',       'tag' => 'neuwagen',     ),     10660 =>      
 array (       'id' => '10660',       'tag' => 'seat',     ),     17803 =>      
 array (       'id' => '17803',       'tag' => 'sportliche ausstrahlung',     ),     74 =>      
 array (       'id' => '74',       'tag' => 'web 2.0',     ),   ),    'categories' =>    
 array (     16082 =>      
 array (       'id' => '16082',       'tag' => 'Auto & Motorrad',     ),     51 =>      
 array (       'id' => '51',       'tag' => 'Blogosphäre',     ),     66 =>      
 array (       'id' => '66',       'tag' => 'Neues & Trends',     ),     68 =>      
 array (       'id' => '68',       'tag' => 'Privat',     ),   ), );

 printarr($a);
 printarr($a['languages'][76]['tag']);
 parintarr($a['targets'][81]['id']); 
 function printarr($in){
 echo "\n";
 print_r($in);
 echo "\n";
 }
 //run in php command line php path/to/file.php to test, switching otu the print_r.

Why are interface variables static and final by default?

because:

Static : as we can't have objects of interfaces so we should avoid using Object level member variables and should use class level variables i.e. static.

Final : so that we should not have ambiguous values for the variables(Diamond problem - Multiple Inheritance).

And as per the documentation interface is a contract and not an implementation.

reference: Abhishek Jain's answer on quora

How do you reverse a string in place in C or C++?

Non-evil C, assuming the common case where the string is a null-terminated char array:

#include <stddef.h>
#include <string.h>

/* PRE: str must be either NULL or a pointer to a 
 * (possibly empty) null-terminated string. */
void strrev(char *str) {
  char temp, *end_ptr;

  /* If str is NULL or empty, do nothing */
  if( str == NULL || !(*str) )
    return;

  end_ptr = str + strlen(str) - 1;

  /* Swap the chars */
  while( end_ptr > str ) {
    temp = *str;
    *str = *end_ptr;
    *end_ptr = temp;
    str++;
    end_ptr--;
  }
}

How can I rollback an UPDATE query in SQL server 2005?

begin transaction

// execute SQL code here

rollback transaction

If you've already executed the query and want to roll it back, unfortunately your only real option is to restore a database backup. If you're using Full backups, then you should be able to restore the database to a specific point in time.

Why I get 411 Length required error?

Hey i'm using Volley and was getting Server error 411, I added to the getHeaders method the following line :

params.put("Content-Length","0");

And it solved my issue

Insert Data Into Tables Linked by Foreign Key

You can do it in one sql statement for existing customers, 3 statements for new ones. All you have to do is be an optimist and act as though the customer already exists:

insert into "order" (customer_id, price) values \
((select customer_id from customer where name = 'John'), 12.34);

If the customer does not exist, you'll get an sql exception which text will be something like:

null value in column "customer_id" violates not-null constraint

(providing you made customer_id non-nullable, which I'm sure you did). When that exception occurs, insert the customer into the customer table and redo the insert into the order table:

insert into customer(name) values ('John');
insert into "order" (customer_id, price) values \
((select customer_id from customer where name = 'John'), 12.34);

Unless your business is growing at a rate that will make "where to put all the money" your only real problem, most of your inserts will be for existing customers. So, most of the time, the exception won't occur and you'll be done in one statement.

What is VanillaJS?

This is a joke for those who are excited about the JavaScript frameworks and do not know the pure Javascript.

So VanillaJS is the same as pure Javascript.

Vanilla in slang means:

unexciting, normal, conventional, boring

Here is a nice presentation on YouTube about VanillaJS: What is Vanilla JS?

How to handle floats and decimal separators with html5 input type number

uses a text type but forces the appearance of the numeric keyboard

<input value="12,4" type="text" inputmode="numeric" pattern="[-+]?[0-9]*[.,]?[0-9]+">

the inputmode tag is the solution

Find the most frequent number in a NumPy array

If you're willing to use SciPy:

>>> from scipy.stats import mode
>>> mode([1,2,3,1,2,1,1,1,3,2,2,1])
(array([ 1.]), array([ 6.]))
>>> most_frequent = mode([1,2,3,1,2,1,1,1,3,2,2,1])[0][0]
>>> most_frequent
1.0

What's the difference between git reset --mixed, --soft, and --hard?

Please be aware, this is a simplified explanation intended as a first step in seeking to understand this complex functionality.

May be helpful for visual learners who want to visualise what their project state looks like after each of these commands:

Given: - A - B - C (master)


For those who use Terminal with colour turned on (git config --global color.ui auto):

git reset --soft A and you will see B and C's stuff in green (staged and ready to commit)

git reset --mixed A (or git reset A) and you will see B and C's stuff in red (unstaged and ready to be staged (green) and then committed)

git reset --hard A and you will no longer see B and C's changes anywhere (will be as if they never existed)


Or for those who use a GUI program like 'Tower' or 'SourceTree'

git reset --soft A and you will see B and C's stuff in the 'staged files' area ready to commit

git reset --mixed A (or git reset A) and you will see B and C's stuff in the 'unstaged files' area ready to be moved to staged and then committed

git reset --hard A and you will no longer see B and C's changes anywhere (will be as if they never existed)

How to auto generate migrations with Sequelize CLI from Sequelize models?

If you want to create model along with migration use this command:-

sequelize model:create --name regions --attributes name:string,status:boolean --underscored

--underscored it is used to create column having underscore like:- created_at,updated_at or any other column having underscore and support user defined columns having underscore.

Installing ADB on macOS

Note that if you use Android Studio and download through its SDK Manager, the SDK is downloaded to ~/Library/Android/sdk by default, not ~/.android-sdk-macosx.

I would rather add this as a comment to @brismuth's excellent answer, but it seems I don't have enough reputation points yet.

How to select all checkboxes with jQuery?

$("#select_all").change(function () {

    $('input[type="checkbox"]').prop("checked", $(this).prop("checked"));

});  

Counting Number of Letters in a string variable

What is wrong with using string.Length?

// len will be 5
int len = "Hello".Length;

How to add a button dynamically in Android?

I've used this (or very similar) code to add several TextViews to a LinearLayout:

// Quick & dirty pre-made list of text labels...
String names[] = {"alpha", "beta", "gamma", "delta", "epsilon"};
int namesLength = 5;

// Create a LayoutParams...
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
    LinearLayout.LayoutParams.WRAP_CONTENT, 
    LinearLayout.LayoutParams.FILL_PARENT);

// Get existing UI containers...
LinearLayout nameButtons = (LinearLayout) view.findViewById(R.id.name_buttons);
TextView label = (TextView) view.findViewById(R.id.master_label);

TextView tv;

for (int i = 0; i < namesLength; i++) {
    // Grab the name for this "button"
    final String name = names[i];

    tv = new TextView(context);
    tv.setText(name);

    // TextViews CAN have OnClickListeners
    tv.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            label.setText("Clicked button for " + name); 
        }
    });

    nameButtons.addView(tv, params);
}

The main difference between this and dicklaw795's code is it doesn't set() and re-get() the ID for each TextView--I found it unnecessary, although I may need it to later identify each button in a common handler routine (e.g. one called by onClick() for each TextView).

How do I `jsonify` a list in Flask?

If you are searching literally the way to return a JSON list in flask and you are completly sure that your variable is a list then the easy way is (where bin is a list of 1's and 0's):

   return jsonify({'ans':bin}), 201

Finally, in your client you will obtain something like

{ "ans": [ 0.0, 0.0, 1.0, 1.0, 0.0 ] }

Viewing full version tree in git

There is a very good answer to the same question.
Adding following lines to "~/.gitconfig":

[alias]
lg1 = log --graph --abbrev-commit --decorate --date=relative --format=format:'%C(bold blue)%h%C(reset) - %C(bold green)(%ar)%C(reset) %C(white)%s%C(reset) %C(dim white)- %an%C(reset)%C(bold yellow)%d%C(reset)' --all
lg2 = log --graph --abbrev-commit --decorate --format=format:'%C(bold blue)%h%C(reset) - %C(bold cyan)%aD%C(reset) %C(bold green)(%ar)%C(reset)%C(bold yellow)%d%C(reset)%n''          %C(white)%s%C(reset) %C(dim white)- %an%C(reset)' --all
lg = !"git lg1"

How can I search an array in VB.NET?

If you want an efficient search that is often repeated, first sort the array (Array.Sort) and then use Array.BinarySearch.

Matplotlib: ValueError: x and y must have same first dimension

Changing your lists to numpy arrays will do the job!!

import matplotlib.pyplot as plt
from scipy import stats
import numpy as np 

x = np.array([0.46,0.59,0.68,0.99,0.39,0.31,1.09,0.77,0.72,0.49,0.55,0.62,0.58,0.88,0.78]) # x is a numpy array now
y = np.array([0.315,0.383,0.452,0.650,0.279,0.215,0.727,0.512,0.478,0.335,0.365,0.424,0.390,0.585,0.511]) # y is a numpy array now
xerr = [0.01]*15
yerr = [0.001]*15

plt.rc('font', family='serif', size=13)
m, b = np.polyfit(x, y, 1)
plt.plot(x,y,'s',color='#0066FF')
plt.plot(x, m*x + b, 'r-') #BREAKS ON THIS LINE
plt.errorbar(x,y,xerr=xerr,yerr=0,linestyle="None",color='black')
plt.xlabel('$\Delta t$ $(s)$',fontsize=20)
plt.ylabel('$\Delta p$ $(hPa)$',fontsize=20)
plt.autoscale(enable=True, axis=u'both', tight=False)
plt.grid(False)
plt.xlim(0.2,1.2)
plt.ylim(0,0.8)
plt.show()

enter image description here

How to convert rdd object to dataframe in spark

Here is a simple example of converting your List into Spark RDD and then converting that Spark RDD into Dataframe.

Please note that I have used Spark-shell's scala REPL to execute following code, Here sc is an instance of SparkContext which is implicitly available in Spark-shell. Hope it answer your question.

scala> val numList = List(1,2,3,4,5)
numList: List[Int] = List(1, 2, 3, 4, 5)

scala> val numRDD = sc.parallelize(numList)
numRDD: org.apache.spark.rdd.RDD[Int] = ParallelCollectionRDD[80] at parallelize at <console>:28

scala> val numDF = numRDD.toDF
numDF: org.apache.spark.sql.DataFrame = [_1: int]

scala> numDF.show
+---+
| _1|
+---+
|  1|
|  2|
|  3|
|  4|
|  5|
+---+

CSS background-image not working

 <span class="btn-pTool">
 <a class="btn-pToolName" href="#"></a>
 </span>

That's empty. Try adding a non breaking space to give the link and span some contents:

 <span class="btn-pTool">
 <a class="btn-pToolName" href="#">&nbsp;</a>
 </span>

It's also worth noting that the CSS spec says that you can't give a span a background image because spans are not block elements. Put the background image code in the div's class style, or use <p> instead of <span>. Some browsers might let you put a background in a span, but not all will (perhaps older versions of IE).

AttributeError: 'str' object has no attribute

The problem is in your playerMovement method. You are creating the string name of your room variables (ID1, ID2, ID3):

letsago = "ID" + str(self.dirDesc.values())

However, what you create is just a str. It is not the variable. Plus, I do not think it is doing what you think its doing:

>>>str({'a':1}.values())
'dict_values([1])'

If you REALLY needed to find the variable this way, you could use the eval function:

>>>foo = 'Hello World!'
>>>eval('foo')
'Hello World!'

or the globals function:

class Foo(object):
    def __init__(self):
        super(Foo, self).__init__()
    def test(self, name):
        print(globals()[name])

foo = Foo()
bar = 'Hello World!'
foo.text('bar')

However, instead I would strongly recommend you rethink you class(es). Your userInterface class is essentially a Room. It shouldn't handle player movement. This should be within another class, maybe GameManager or something like that.

String comparison: InvariantCultureIgnoreCase vs OrdinalIgnoreCase?

FXCop typically prefers OrdinalIgnoreCase. But your requirements may vary.

For English there is very little difference. It is when you wander into languages that have different written language constructs that this becomes an issue. I am not experienced enough to give you more than that.

OrdinalIgnoreCase

The StringComparer returned by the OrdinalIgnoreCase property treats the characters in the strings to compare as if they were converted to uppercase using the conventions of the invariant culture, and then performs a simple byte comparison that is independent of language. This is most appropriate when comparing strings that are generated programmatically or when comparing case-insensitive resources such as paths and filenames. http://msdn.microsoft.com/en-us/library/system.stringcomparer.ordinalignorecase.aspx

InvariantCultureIgnoreCase

The StringComparer returned by the InvariantCultureIgnoreCase property compares strings in a linguistically relevant manner that ignores case, but it is not suitable for display in any particular culture. Its major application is to order strings in a way that will be identical across cultures. http://msdn.microsoft.com/en-us/library/system.stringcomparer.invariantcultureignorecase.aspx

The invariant culture is the CultureInfo object returned by the InvariantCulture property.

The InvariantCultureIgnoreCase property actually returns an instance of an anonymous class derived from the StringComparer class.

How to read a config file using python

This looks like valid Python code, so if the file is on your project's classpath (and not in some other directory or in arbitrary places) one way would be just to rename the file to "abc.py" and import it as a module, using import abc. You can even update the values using the reload function later. Then access the values as abc.path1 etc.

Of course, this can be dangerous in case the file contains other code that will be executed. I would not use it in any real, professional project, but for a small script or in interactive mode this seems to be the simplest solution.

Just put the abc.py into the same directory as your script, or the directory where you open the interactive shell, and do import abc or from abc import *.

Windows task scheduler error 101 launch failure code 2147943785

I have the same today on Win7.x64, this solve it.

Right Click MyComputer > Manage > Local Users and Groups > Groups > Administrators double click > your name should be there, if not press add...

Copy file or directories recursively in Python

To add on Tzot's and gns answers, here's an alternative way of copying files and folders recursively. (Python 3.X)

import os, shutil

root_src_dir = r'C:\MyMusic'    #Path/Location of the source directory
root_dst_dir = 'D:MusicBackUp'  #Path to the destination folder

for src_dir, dirs, files in os.walk(root_src_dir):
    dst_dir = src_dir.replace(root_src_dir, root_dst_dir, 1)
    if not os.path.exists(dst_dir):
        os.makedirs(dst_dir)
    for file_ in files:
        src_file = os.path.join(src_dir, file_)
        dst_file = os.path.join(dst_dir, file_)
        if os.path.exists(dst_file):
            os.remove(dst_file)
        shutil.copy(src_file, dst_dir)

Should it be your first time and you have no idea how to copy files and folders recursively, I hope this helps.

OpenJDK availability for Windows OS

I recently came across this site: https://adoptopenjdk.net/

Seems reliable to me. Haven't tried myself but surely will give it a try.

License:

License(s) Build scripts and other code to produce the binaries, the website and other build infrastructure are licensed under Apache License, Version 2.0. OpenJDK code itself is licensed under GPL v2 with Classpath Exception.

EDIT: I was also delighted to learn that AdoptOpenJDK MSI installer (JDK and JRE) now comes with IcedTeaWeb, which is a replacement for Oracle WebStart - simple installer with almost 'next-next-next-finish' and the JWS applications works like they used to.

Hashmap holding different data types as values for instance Integer, String and Object

Define a class to store your data first

public class YourDataClass {

    private String messageType;
    private Timestamp timestamp;
    private int count;
    private int version;

    // your get/setters
    ...........
}

And then initialize your map:

Map<Integer, YourDataClass> map = new HashMap<Integer, YourDataClass>();

What is the best way to concatenate two vectors?

AB.reserve( A.size() + B.size() ); // preallocate memory
AB.insert( AB.end(), A.begin(), A.end() );
AB.insert( AB.end(), B.begin(), B.end() );

Everytime I run gulp anything, I get a assertion error. - Task function must be specified

It's not good to keep changing the gulp & npm versions in-order to fix the errors. I was getting several exceptions last days after reinstall my working machine. And wasted tons of minutes to re-install & fixing those.

So, I decided to upgrade all to latest versions:

npm -v : v12.13.0 
node -v : 6.13.0
gulp -v : CLI version: 2.2.0 Local version: 4.0.2

This error is getting because of the how it has coded in you gulpfile but not the version mismatch. So, Here you have to change 2 things in the gulpfile to aligned with Gulp version 4. Gulp 4 has changed how initiate the task than Version 3.

  1. In version 4, you have to defined the task as a function, before call it as a gulp task by it's string name. In V3:

gulp.task('serve', ['sass'], function() {..});

But in V4 it should be like:

function serve() {
...
}
gulp.task('serve', gulp.series(sass));
  1. As @Arthur has mentioned, you need to change the way of passing arguments to the task function. It was like this in V3:

gulp.task('serve', ['sass'], function() { ... });

But in V4, it should be:

gulp.task('serve', gulp.series(sass));

Regular expression for 10 digit number without any special characters

An example of how to implement it:

public bool ValidateSocialSecNumber(string socialSecNumber)
{
    //Accepts only 10 digits, no more no less. (Like Mike's answer)
    Regex pattern = new Regex(@"(?<!\d)\d{10}(?!\d)");

    if(pattern.isMatch(socialSecNumber))
    {
        //Do something
        return true;
    }
    else
    {
        return false;
    }
}

You could've also done it in another way by e.g. using Match and then wrapping a try-catch block around the pattern matching. However, if a wrong input is given quite often, it's quite expensive to throw an exception. Thus, I prefer the above way, in simple cases at least.

VBA general way for pulling data out of SAP

This all depends on what sort of access you have to your SAP system. An ABAP program that exports the data and/or an RFC that your macro can call to directly get the data or have SAP create the file is probably best.

However as a general rule people looking for this sort of answer are looking for an immediate solution that does not require their IT department to spend months customizing their SAP system.

In that case you probably want to use SAP GUI Scripting. SAP GUI scripting allows you to automate the Windows SAP GUI in much the same way as you automate Excel. In fact you can call the SAP GUI directly from an Excel macro. Read up more on it here. The SAP GUI has a macro recording tool much like Excel does. It records macros in VBScript which is nearly identical to Excel VBA and can usually be copied and pasted into an Excel macro directly.

Example Code

Here is a simple example based on a SAP system I have access to.

Public Sub SimpleSAPExport()
  Set SapGuiAuto  = GetObject("SAPGUI") 'Get the SAP GUI Scripting object
  Set SAPApp = SapGuiAuto.GetScriptingEngine 'Get the currently running SAP GUI 
  Set SAPCon = SAPApp.Children(0) 'Get the first system that is currently connected
  Set session = SAPCon.Children(0) 'Get the first session (window) on that connection

  'Start the transaction to view a table
  session.StartTransaction "SE16"

  'Select table T001
  session.findById("wnd[0]/usr/ctxtDATABROWSE-TABLENAME").Text = "T001"
  session.findById("wnd[0]/tbar[1]/btn[7]").Press

  'Set our selection criteria
  session.findById("wnd[0]/usr/txtMAX_SEL").text = "2"
  session.findById("wnd[0]/tbar[1]/btn[8]").press

  'Click the export to file button
  session.findById("wnd[0]/tbar[1]/btn[45]").press

  'Choose the export format
  session.findById("wnd[1]/usr/subSUBSCREEN_STEPLOOP:SAPLSPO5:0150/sub:SAPLSPO5:0150/radSPOPLI-SELFLAG[1,0]").select
  session.findById("wnd[1]/tbar[0]/btn[0]").press

  'Choose the export filename
  session.findById("wnd[1]/usr/ctxtDY_FILENAME").text = "test.txt"
  session.findById("wnd[1]/usr/ctxtDY_PATH").text = "C:\Temp\"

  'Export the file
  session.findById("wnd[1]/tbar[0]/btn[0]").press
End Sub

Script Recording

To help find the names of elements such aswnd[1]/tbar[0]/btn[0] you can use script recording. Click the customize local layout button, it probably looks a bit like this: Customize Local Layout
Then find the Script Recording and Playback menu item.
Script Recording and Playback
Within that the More button allows you to see/change the file that the VB Script is recorded to. The output format is a bit messy, it records things like selecting text, clicking inside a text field, etc.

Edit: Early and Late binding

The provided script should work if copied directly into a VBA macro. It uses late binding, the line Set SapGuiAuto = GetObject("SAPGUI") defines the SapGuiAuto object.

If however you want to use early binding so that your VBA editor might show the properties and methods of the objects you are using, you need to add a reference to sapfewse.ocx in the SAP GUI installation folder.

Why doesn't RecyclerView have onItemClickListener()?

I use this method to start an Intent from RecyclerView:

@Override
 public void onBindViewHolder(ViewHolder viewHolder, int i) {

    final MyClass myClass = mList.get(i);
    viewHolder.txtViewTitle.setText(myclass.name);
   ...
    viewHolder.itemView.setOnClickListener(new View.OnClickListener() {
      @Override
       public void onClick(View v){
             Intent detailIntent = new Intent(mContext, type.class);                                                            
             detailIntent.putExtra("MyClass", myclass);
             mContext.startActivity(detailIntent);
       }
}
);

Detected both log4j-over-slf4j.jar AND slf4j-log4j12.jar on the class path, preempting StackOverflowError.

For gradle

compile('org.xxx:xxx:1.0-SNAPSHOT'){
    exclude module: 'log4j'
    exclude module: 'slf4j-log4j12'
}

Change text color with Javascript?

innerHTML is a string representing the contents of the element.

You want to modify the element itself. Drop the .innerHTML part.

Gradle project refresh failed after Android Studio update

  1. Go to C://Users//
  2. Remove .AndroidStudio2.x
  3. Open Android Studio and config for initialization again.

Check if string contains \n Java

If the string was constructed in the same program, I would recommend using this:

String newline = System.getProperty("line.separator");
boolean hasNewline = word.contains(newline);

But if you are specced to use \n, this driver illustrates what to do:

class NewLineTest {
    public static void main(String[] args) {
        String hasNewline = "this has a newline\n.";
        String noNewline = "this doesn't";

        System.out.println(hasNewline.contains("\n"));
        System.out.println(hasNewline.contains("\\n"));
        System.out.println(noNewline.contains("\n"));
        System.out.println(noNewline.contains("\\n"));

    }

}

Resulted in

true
false
false
false

In reponse to your comment:

class NewLineTest {
    public static void main(String[] args) {
        String word = "test\n.";
        System.out.println(word.length());
        System.out.println(word);
        word = word.replace("\n","\n ");
        System.out.println(word.length());
        System.out.println(word);

    }

}

Results in

6
test
.
7
test
 .

Can constructors throw exceptions in Java?

Yes, constructors are allowed to throw exceptions.

However, be very wise in choosing what exceptions they should be - checked exceptions or unchecked. Unchecked exceptions are basically subclasses of RuntimeException.

In almost all cases (I could not come up with an exception to this case), you'll need to throw a checked exception. The reason being that unchecked exceptions (like NullPointerException) are normally due to programming errors (like not validating inputs sufficiently).

The advantage that a checked exception offers is that the programmer is forced to catch the exception in his instantiation code, and thereby realizes that there can be a failure to create the object instance. Of course, only a code review will catch the poor programming practice of swallowing an exception.

Linux: command to open URL in default browser

In Java (version 6+), you can also do:

Desktop d = Desktop.getDesktop();
d.browse(uri);

Though this won't work on all Linuxes. At the time of writing, Gnome is supported, KDE isn't.

Inline comments for Bash?

I find it easiest (and most readable) to just copy the line and comment out the original version:

#Old version of ls:
#ls -l $([ ] && -F is turned off) -a /etc
ls -l -a /etc

how to break the _.each function in underscore.js

worked in my case

var arr2 = _.filter(arr, function(item){
    if ( item == 3 ) return item;
});

How do I test if a variable does not equal either of two values?

May I suggest trying to use in else if statement in your if/else statement. And if you don't want to run any code that not under any conditions you want you can just leave the else out at the end of the statement. else if can also be used for any number of diversion paths that need things to be a certain condition for each.

if(condition 1){

} else if (condition 2) {

}else {

}

Export table to file with column headers (column names) using the bcp utility and SQL Server 2008

I have successfully achieved this with the below code. Put the below code in an SQL Server new query window and try:

CREATE TABLE tempDBTableDetails ( TableName VARCHAR(500), [RowCount] VARCHAR(500), TotalSpaceKB VARCHAR(500),
                UsedSpaceKB VARCHAR(500), UnusedSpaceKB VARCHAR(500) )

    -- STEP 1 ::
    DECLARE @cmd VARCHAR(4000)

INSERT INTO tempDBTableDetails
SELECT 'TableName', 'RowCount', 'TotalSpaceKB', 'UsedSpaceKB', 'UnusedSpaceKB'
INSERT INTO tempDBTableDetails
SELECT
    S.name +'.'+ T.name as TableName,
    Convert(varchar,Cast(SUM(P.rows) as Money),1) as [RowCount],
    Convert(varchar,Cast(SUM(a.total_pages) * 8 as Money),1) AS TotalSpaceKB,
    Convert(varchar,Cast(SUM(a.used_pages) * 8 as Money),1) AS UsedSpaceKB,
    (SUM(a.total_pages) - SUM(a.used_pages)) * 8 AS UnusedSpaceKB
FROM sys.tables T
INNER JOIN sys.partitions P ON P.OBJECT_ID = T.OBJECT_ID
INNER JOIN sys.schemas S ON T.schema_id = S.schema_id
INNER JOIN sys.allocation_units A ON p.partition_id = a.container_id
WHERE T.is_ms_shipped = 0 AND P.index_id IN (1,0)
GROUP BY S.name, T.name
ORDER BY SUM(P.rows) DESC

-- SELECT * FROM [FIINFRA-DB-SIT].dbo.tempDBTableDetails ORDER BY LEN([RowCount]) DESC

SET @cmd = 'bcp "SELECT * FROM [FIINFRA-DB-SIT].dbo.tempDBTableDetails ORDER BY LEN([RowCount]) DESC" queryout "D:\Milind\export.xls" -U sa -P dbowner -c'
    Exec xp_cmdshell @cmd

--DECLARE @HeaderCmd VARCHAR(4000)
--SET @HeaderCmd = 'SELECT ''TableName'', ''RowCount'', ''TotalSpaceKB'', ''UsedSpaceKB'', ''UnusedSpaceKB'''
exec master..xp_cmdshell 'BCP "SELECT ''TableName'', ''RowCount'', ''TotalSpaceKB'', ''UsedSpaceKB'', ''UnusedSpaceKB''" queryout "d:\milind\header.xls" -U sa -P dbowner -c'
exec master..xp_cmdshell 'copy /b "d:\Milind\header.xls"+"d:\Milind\export.xls" "d:/Milind/result.xls"'

exec master..xp_cmdshell 'del "d:\Milind\header.xls"'
exec master..xp_cmdshell 'del "d:\Milind\export.xls"'

DROP TABLE tempDBTableDetails

SQL to search objects, including stored procedures, in Oracle

I would use DBA_SOURCE (if you have access to it) because if the object you require is not owned by the schema under which you are logged in you will not see it.

If you need to know the functions and Procs inside the packages try something like this:

select * from all_source
 where type = 'PACKAGE'
   and (upper(text) like '%FUNCTION%' or upper(text) like '%PROCEDURE%')
   and owner != 'SYS';

The last line prevents all the sys stuff (DBMS_ et al) from being returned. This will work in user_source if you just want your own schema stuff.

Creating a node class in Java

Welcome to Java! This Nodes are like a blocks, they must be assembled to do amazing things! In this particular case, your nodes can represent a list, a linked list, You can see an example here:

public class ItemLinkedList {
    private ItemInfoNode head;
    private ItemInfoNode tail;
    private int size = 0;

    public int getSize() {
        return size;
    }

    public void addBack(ItemInfo info) {
        size++;
        if (head == null) {
            head = new ItemInfoNode(info, null, null);
            tail = head;
        } else {
            ItemInfoNode node = new ItemInfoNode(info, null, tail);
            this.tail.next =node;
            this.tail = node;
        }
    }

    public void addFront(ItemInfo info) {
        size++;
        if (head == null) {
            head = new ItemInfoNode(info, null, null);
            tail = head;
        } else {
            ItemInfoNode node = new ItemInfoNode(info, head, null);
            this.head.prev = node;
            this.head = node;
        }
    }

    public ItemInfo removeBack() {
        ItemInfo result = null;
        if (head != null) {
            size--;
            result = tail.info;
            if (tail.prev != null) {
                tail.prev.next = null;
                tail = tail.prev;
            } else {
                head = null;
                tail = null;
            }
        }
        return result;
    }

    public ItemInfo removeFront() {
        ItemInfo result = null;
        if (head != null) {
            size--;
            result = head.info;
            if (head.next != null) {
                head.next.prev = null;
                head = head.next;
            } else {
                head = null;
                tail = null;
            }
        }
        return result;
    }

    public class ItemInfoNode {

        private ItemInfoNode next;
        private ItemInfoNode prev;
        private ItemInfo info;

        public ItemInfoNode(ItemInfo info, ItemInfoNode next, ItemInfoNode prev) {
            this.info = info;
            this.next = next;
            this.prev = prev;
        }

        public void setInfo(ItemInfo info) {
            this.info = info;
        }

        public void setNext(ItemInfoNode node) {
            next = node;
        }

        public void setPrev(ItemInfoNode node) {
            prev = node;
        }

        public ItemInfo getInfo() {
            return info;
        }

        public ItemInfoNode getNext() {
            return next;
        }

        public ItemInfoNode getPrev() {
            return prev;
        }
    }
}

EDIT:

Declare ItemInfo as this:

public class ItemInfo {
    private String name;
    private String rfdNumber;
    private double price;
    private String originalPosition;

    public ItemInfo(){
    }

    public ItemInfo(String name, String rfdNumber, double price, String originalPosition) {
        this.name = name;
        this.rfdNumber = rfdNumber;
        this.price = price;
        this.originalPosition = originalPosition;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getRfdNumber() {
        return rfdNumber;
    }

    public void setRfdNumber(String rfdNumber) {
        this.rfdNumber = rfdNumber;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }

    public String getOriginalPosition() {
        return originalPosition;
    }

    public void setOriginalPosition(String originalPosition) {
        this.originalPosition = originalPosition;
    }
}

Then, You can use your nodes inside the linked list like this:

public static void main(String[] args) {
    ItemLinkedList list = new ItemLinkedList();
    for (int i = 1; i <= 10; i++) {
        list.addBack(new ItemInfo("name-"+i, "rfd"+i, i, String.valueOf(i)));

    }
    while (list.size() > 0){
        System.out.println(list.removeFront().getName());
    }
}

The import org.apache.commons cannot be resolved in eclipse juno

Look for "poi-3.17.jar"!!!

  1. Download from "https://poi.apache.org/download.html".
  2. Click the one Binary Distribution -> poi-bin-3.17-20170915.tar.gz
  3. Unzip the file download and look for this "poi-3.17.jar".

Problem solved and errors disappeared.

css ellipsis on second line

All the answers here are wrong, they missing important piece, the height

.container{
    width:200px;
    height:600px;
    background:red
}
.title {
        overflow: hidden;
        line-height: 20px;
        height: 40px;
        text-overflow: ellipsis;
        display: -webkit-box;
        -webkit-line-clamp: 2;
        -webkit-box-orient: vertical;
    }
<div class="container">
    <div class="title">this is a long text you cant cut it in half</div>
</div>

How can I concatenate a string within a loop in JSTL/JSP?

Is JSTL's join(), what you searched for?

<c:set var="myVar" value="${fn:join(myParams.items, ' ')}" />

Share Text on Facebook from Android App via ACTION_SEND

It appears that it's a bug in the Facebook app that was reported in April 2011 and has still yet to be fixed by the Android Facebook developers.

The only work around for the moment is to use their SDK.

Want to upgrade project from Angular v5 to Angular v6

There are few steps to upgrade 2/4/5 to Angular 6.

npm uninstall --save-dev angular-cli
npm install --save-dev @angular/cli@latest
npm install

To fix the issue related to "angular.json" :-

ng update @angular/cli --migrate-only --from=1.7.4

Store MIGRATION
https://github.com/ngrx/platform/blob/master/MIGRATION.md#ngrxstore

RXJS MIGRATION
https://www.academind.com/learn/javascript/rxjs-6-what-changed/

Hoping this will help you :)

Is there a way to return a list of all the image file names from a folder using only Javascript?

This will list all jpg files in the folder you define under url: and append them to a div as a paragraph. Can do it with ul li as well.

$.ajax({
  url: "YOUR FOLDER",
  success: function(data){
     $(data).find("a:contains(.jpg)").each(function(){
        // will loop through 
        var images = $(this).attr("href");

        $('<p></p>').html(images).appendTo('a div of your choice')

     });
  }
});