Programs & Examples On #S

S is a statistical programming language

How to get summary statistics by group

take a look at the plyr package. Specifically, ddply

ddply(df, .(group), summarise, mean=mean(dt), sum=sum(dt))

Printing an array in C++?

This might help //Printing The Array

for (int i = 0; i < n; i++)
{cout << numbers[i];}

n is the size of the array

Scala best way of turning a Collection into a Map-by-key?

This can be implemented immutably and with a single traversal by folding through the collection as follows.

val map = c.foldLeft(Map[P, T]()) { (m, t) => m + (t.getP -> t) }

The solution works because adding to an immutable Map returns a new immutable Map with the additional entry and this value serves as the accumulator through the fold operation.

The tradeoff here is the simplicity of the code versus its efficiency. So, for large collections, this approach may be more suitable than using 2 traversal implementations such as applying map and toMap.

Install a Python package into a different directory using pip?

Nobody seems to have mentioned the -t option but that the easiest:

pip install -t <direct directory> <package>

Get keys from HashMap in Java

public class MyHashMapKeys {

    public static void main(String a[]){
        HashMap<String, String> hm = new HashMap<String, String>();
        //add key-value pair to hashmap
        hm.put("first", "FIRST INSERTED");
        hm.put("second", "SECOND INSERTED");
        hm.put("third","THIRD INSERTED");
        System.out.println(hm);
        Set<String> keys = hm.keySet();
        for(String key: keys){
            System.out.println(key);
        }
    }
}

How to say no to all "do you want to overwrite" prompts in a batch file copy?

I expect xxcopy has an option for that.

Bingo:

http://www.xxcopy.com/xxcopy27.htm#tag_231

2.3   By comparison with the file in destination

    The switches in this group select files based on the
    comparison between the files in the source and those in
    the destination.  They are often used for periodic backup
    and directory synchronization purposes. These switches
    were originally created as variations of directory backup.
    They are also convenient for selecting files for deletion.

2.3.1  by Presence/Absence

    The /BB and /U switches are the two switches which select
    files by the pure presence or absence as the criteria.
    Other switches in the this group (Group 2.3) are also
    affected by the file in the destination, but for a
    particular characteristics for comparison's sake.

    /BB  Selects files that are present in source but not in destination.
    /U   Selects files that are present in both source and destination.

-Adam

Difference between OpenJDK and Adoptium/AdoptOpenJDK

Update: AdoptOpenJDK has changed its name to Adoptium, as part of its move to the Eclipse Foundation.


OpenJDK ? source code
Adoptium/AdoptOpenJDK ? builds

Difference between OpenJDK and AdoptOpenJDK

The first provides source-code, the other provides builds of that source-code.

Several vendors of Java & OpenJDK

Adoptium of the Eclipse Foundation, formerly known as AdoptOpenJDK, is only one of several vendors distributing implementations of the Java platform. These include:

  • Eclipse Foundation (Adoptium/AdoptOpenJDK)
  • Azul Systems
  • Oracle
  • Red Hat / IBM
  • BellSoft
  • SAP
  • Amazon AWS
  • … and more

See this flowchart of mine to help guide you in picking a vendor for an implementation of the Java platform. Click/tap to zoom.

Flowchart guiding you in choosing a vendor for a Java 11 implementation

Another resource: This comparison matrix by Azul Systems is useful, and seems true and fair to my mind.

Here is a list of considerations and motivations to consider in choosing a vendor and implementation.

Motivations in choosing a vendor for Java

Some vendors offer you a choice of JIT technologies.

Diagram showing history of HotSpot & JRockit merging, and OpenJ9 both available in AdoptOpenJDK

To understand more about this Java ecosystem, read Java Is Still Free

How to exit if a command failed?

You can also use, if you want to preserve exit error status, and have a readable file with one command per line:

my_command1 || exit $?
my_command2 || exit $?

This, however will not print any additional error message. But in some cases, the error will be printed by the failed command anyway.

jQuery check if an input is type checkbox?

You can use the pseudo-selector :checkbox with a call to jQuery's is function:

$('#myinput').is(':checkbox')

C# compiler error: "not all code paths return a value"

The compiler doesn't get the intricate logic where you return in the last iteration of the loop, so it thinks that you could exit out of the loop and end up not returning anything at all.

Instead of returning in the last iteration, just return true after the loop:

public static bool isTwenty(int num) {
  for(int j = 1; j <= 20; j++) {
    if(num % j != 0) {
      return false;
    }
  }
  return true;
}

Side note, there is a logical error in the original code. You are checking if num == 20 in the last condition, but you should have checked if j == 20. Also checking if num % j == 0 was superflous, as that is always true when you get there.

How to change the link color in a specific class for a div CSS

smaller-size version:

#register a:link {color: #fff}

Stopping an Android app from console

In eclipse go to the DDMS perspective and in the devices tab click the process you want to kill under the device you want to kill it on. You then just need to press the stop button and it should kill the process.

I'm not sure how you'd do this from the command line tool but there must be a way. Maybe you do it through the adb shell...

Iterator Loop vs index loop

Iterators make your code more generic.
Every standard library container provides an iterator hence if you change your container class in future the loop wont be affected.

What is the best way to iterate over a dictionary?

I wrote an extension to loop over a dictionary.

public static class DictionaryExtension
{
    public static void ForEach<T1, T2>(this Dictionary<T1, T2> dictionary, Action<T1, T2> action) {
        foreach(KeyValuePair<T1, T2> keyValue in dictionary) {
            action(keyValue.Key, keyValue.Value);
        }
    }
}

Then you can call

myDictionary.ForEach((x,y) => Console.WriteLine(x + " - " + y));

how to add a day to a date using jquery datepicker

Try this:

 $('.pickupDate').change(function() {
  var date2 = $('.pickupDate').datepicker('getDate', '+1d'); 
  date2.setDate(date2.getDate()+1); 
  $('.dropoffDate').datepicker('setDate', date2);
});

Elasticsearch difference between MUST and SHOULD bool query

Since this is a popular question, I would like to add that in Elasticsearch version 2 things changed a bit.

Instead of filtered query, one should use bool query in the top level.

If you don't care about the score of must parts, then put those parts into filter key. No scoring means faster search. Also, Elasticsearch will automatically figure out, whether to cache them, etc. must_not is equally valid for caching.

Reference: https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-bool-query.html

Also, mind that "gte": "now" cannot be cached, because of millisecond granularity. Use two ranges in a must clause: one with now/1h and another with now so that the first can be cached for a while and the second for precise filtering accelerated on a smaller result set.

How do I duplicate a line or selection within Visual Studio Code?

This keymap will duplicate the current line if nothing is selected or duplicate the selected words.

  1. Access:

    File/Preferences/Keyboard shortcuts

  2. In the right top corner, click on Open Keyboard Shortcuts (JSON).

  3. Insert this keymap:

     {
       "key": "shift+alt+d",
       "command": "editor.action.duplicateSelection"
     }
    
  4. Use alt+arrows up/down to move the line (Default behaviour of VS Code).

CSS Display an Image Resized and Cropped

img {
  position: absolute;
  clip: rect(0px, 140px, 140px, 0px);
}
<img src="w3css.gif" width="100" height="140" />

Find the greatest number in a list of numbers

You can use the inbuilt function max() with multiple arguments:

print max(1, 2, 3)

or a list:

list = [1, 2, 3]
print max(list)

or in fact anything iterable.

Check if all checkboxes are selected

Part 1 of your question:

var allChecked = true;
$("input.abc").each(function(index, element){
  if(!element.checked){
    allChecked = false;
    return false;
  } 
});

EDIT:

The answer (http://stackoverflow.com/questions/5541387/check-if-all-checkboxes-are-selected/5541480#5541480) above is probably better.

What are abstract classes and abstract methods?

ABSTRACT CLASSES AND ABSTARCT METHODS FULL DESCRIPTION GO THROUGH IT

abstract method do not have body.A well defined method can't be declared abstract.

A class which has abstract method must be declared as abstract.

Abstract class can't be instantiated.

Targeting only Firefox with CSS

A variation on your idea is to have a server-side USER-AGENT detector that will figure out what style sheet to attach to the page. This way you can have a firefox.css, ie.css, opera.css, etc.

You can accomplish a similar thing in Javascript itself, although you may not regard it as clean.

I have done a similar thing by having a default.css which includes all common styles and then specific style sheets are added to override, or enhance the defaults.

Excel Reference To Current Cell

There is a better way that is safer and will not slow down your application. How Excel is set up, a cell can have either a value or a formula; the formula can not refer to its own cell. You end up with an infinite loop, since the new value would cause another calculation... . Use a helper column to calculate the value based on what you put in the other cell. For Example:

Column A is a True or False, Column B contains a monetary value, Column C contains the folowing formula: =B1

Now, to calculate that column B will be highlighted yellow in a conditional format only if Column A is True and Column B is greater than Zero...

=AND(A1=True,C1>0)

You can then choose to hide column C

Hidden property of a button in HTML

<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4/jquery.min.js"></script>
<script>

function showButtons () { $('#b1, #b2, #b3').show(); }

</script>
<style type="text/css">
#b1, #b2, #b3 {
display: none;
}

</style>
</head>
<body>

<a href="#" onclick="showButtons();">Show me the money!</a>

<input type="submit" id="b1" value="B1" />
<input type="submit" id="b2" value="B2"/>
<input type="submit" id="b3" value="B3" />

</body>
</html>

Escaping single quote in PHP when inserting into MySQL

You should be escaping each of these strings (in both snippets) with mysql_real_escape_string().

http://us3.php.net/mysql-real-escape-string

The reason your two queries are behaving differently is likely because you have magic_quotes_gpc turned on (which you should know is a bad idea). This means that strings gathered from $_GET, $_POST and $_COOKIES are escaped for you (i.e., "O'Brien" -> "O\'Brien").

Once you store the data, and subsequently retrieve it again, the string you get back from the database will not be automatically escaped for you. You'll get back "O'Brien". So, you will need to pass it through mysql_real_escape_string().

How to replace all special character into a string using C#

Assume you want to replace symbols which are not digits or letters (and _ character as @Guffa correctly pointed):

string input = "Hello@Hello&Hello(Hello)";
string result = Regex.Replace(input, @"[^\w\d]", ",");
// Hello,Hello,Hello,Hello,

You can add another symbols which should not be replaced. E.g. if you want white space symbols to stay, then just add \s to pattern: \[^\w\d\s]

How do I detect what .NET Framework versions and service packs are installed?

There is an official Microsoft answer to this question at the following knowledge base article:

Article ID: 318785 - Last Review: November 7, 2008 - Revision: 20.1 How to determine which versions of the .NET Framework are installed and whether service packs have been applied

Unfortunately, it doesn't appear to work, because the mscorlib.dll version in the 2.0 directory has a 2.0 version, and there is no mscorlib.dll version in either the 3.0 or 3.5 directories even though 3.5 SP1 is installed ... why would the official Microsoft answer be so misinformed?

What is the purpose of Node.js module.exports and how do you use it?

There are some default or existing modules in node.js when you download and install node.js like http, sys etc.

Since they are already in node.js, when we want to use these modules we basically do like import modules, but why? because they are already present in the node.js. Importing is like taking them from node.js and putting them into your program. And then using them.

Whereas Exports is exactly the opposite, you are creating the module you want, let's say the module addition.js and putting that module into the node.js, you do it by exporting it.

Before I write anything here, remember, module.exports.additionTwo is same as exports.additionTwo

Huh, so that's the reason, we do like

exports.additionTwo = function(x)
{return x+2;};

Be careful with the path

Lets say you have created an addition.js module,

exports.additionTwo = function(x){
return x + 2;
};

When you run this on your NODE.JS command prompt:

node
var run = require('addition.js');

This will error out saying

Error: Cannot find module addition.js

This is because the node.js process is unable the addition.js since we didn't mention the path. So, we have can set the path by using NODE_PATH

set NODE_PATH = path/to/your/additon.js

Now, this should run successfully without any errors!!

One more thing, you can also run the addition.js file by not setting the NODE_PATH, back to your nodejs command prompt:

node
var run = require('./addition.js');

Since we are providing the path here by saying it's in the current directory ./ this should also run successfully.

The right way of setting <a href=""> when it's a local file

Organize your files in hierarchical directories and then just use relative paths.

Demo:

HTML (index.html)

<a href='inner/file.html'>link</a>

Directory structure:

base/
base/index.html
base/inner/file.html
....

The EXECUTE permission was denied on the object 'xxxxxxx', database 'zzzzzzz', schema 'dbo'

You can give everybody execute permission:

GRANT Execute on [dbo].your_object to [public]

"Public" is the default database role that all users are a member of.

How to enable relation view in phpmyadmin

Enabling Relation View in phpMyAdmin / MAMP

If you’re using MAMP for your database driven projects you’ll probably be using phpMyAdmin to administer your MySQL database if you’ve decided to go down that route. If you’re creating a database you might be wondering how to create relationships and foriegn keys for your tables.

Firstly you need to check that you have access to the Relation view. To do this open phpMyAdmin and select a database. You need to make sure your tables’ storage engine is set to use InnoDB. Click on a table within your database and choose the Operations tab. Make sure that the storage engine is set to use InnoDB and save your changes.

Now, go back to your table view and click the Structure tab. Depending on your version of phpMyAdmin you should see a link titled Relation view below the table structure. If you can see it you’re good to go. If you can’t you’ll need to follow the steps below to set phpMyAdmin to enable Relations view.

  1. Find /Applications/MAMP/bin/phpMyAdmin/scripts/create_tables.sql
  2. I left this file default but you can change the table name to anything you want. I left mine phpMyAdmin
  3. Open phpMyAdmin and go to the Import tab.
  4. Click the browse button and find the create_tables.sql file and then click Go.
  5. The tables required for Relation view will be added to the database you specified.
  6. Open /Applications/MAMP/bin/phpMyAdmin/config.inc.php
  7. Find the Server(s) configuration code block and replace/uncomment the following code and fill in the values. If you left everything default in the create_tables.sql file then you should just cut and paste the lines below.

    $cfg['Servers'][$i]['pmadb'] = 'phpmyadmin';
    $cfg['Servers'][$i]['bookmarktable'] = 'pma_bookmark';
    $cfg['Servers'][$i]['relation'] = 'pma_relation';
    $cfg['Servers'][$i]['table_info'] = 'pma_table_info';
    $cfg['Servers'][$i]['table_coords'] = 'pma_table_coords';
    $cfg['Servers'][$i]['pdf_pages'] = 'pma_pdf_pages';
    $cfg['Servers'][$i]['column_info'] = 'pma_column_info';
    $cfg['Servers'][$i]['history'] = 'pma_history';
    
  8. Save the file and restart MAMP and refresh your phpMyAdmin console.

  9. Go to your database and view one of your tables in Structure mode. You should now see the Relation view link.

Source: http://newvibes.com/blog/enabling-relation-view-in-phpmyadmin-mamp/

Why do we use arrays instead of other data structures?

For O(1) random access, which can not be beaten.

SQL Server Operating system error 5: "5(Access is denied.)"

I had this problem. Just run SQL Server as administrator

Compare data of two Excel Columns A & B, and show data of Column A that do not exist in B

Put this in C2 and copy down

=IF(ISNA(VLOOKUP(A2,$B$2:$B$65535,1,FALSE)),"not in B","")

Then if the value in A isn't in B the cell in column C will say "not in B".

Curl command line for consuming webServices?

For a SOAP 1.2 Webservice, I normally use

curl --header "content-type: application/soap+xml" --data @filetopost.xml http://domain/path

How to specify an alternate location for the .m2 folder or settings.xml permanently?

Below is the configuration in Maven software by default in MAVEN_HOME\conf\settings.xml.

<settings>
  <!-- localRepository
   | The path to the local repository maven will use to store artifacts.
   |
   | Default: ~/.m2/repository
  <localRepository>/path/to/local/repo</localRepository>
  -->

Add the below line under this configuration, will fulfill the requirement.

<localRepository>custom_path</localRepository>

Ex: <localRepository>D:/MYNAME/settings/.m2/repository</localRepository>

Switch statement with returns -- code correctness

I say remove them. If your code is so unreadable that you need to stick breaks in there 'to be on the safe side', you should reconsider your coding style :)

Also I've always prefered not to mix breaks and returns in the switch statement, but rather stick with one of them.

C# Collection was modified; enumeration operation may not execute

I suspect the error is caused by this:

foreach (KeyValuePair<int, int> kvp in rankings)

rankings is a dictionary, which is IEnumerable. By using it in a foreach loop, you're specifying that you want each KeyValuePair from the dictionary in a deferred manner. That is, the next KeyValuePair is not returned until your loop iterates again.

But you're modifying the dictionary inside your loop:

rankings[kvp.Key] = rankings[kvp.Key] + 4;

which isn't allowed...so you get the exception.

You could simply do this

foreach (KeyValuePair<int, int> kvp in rankings.ToArray())

Dropping Unique constraint from MySQL table

A unique constraint is also an index.

First use SHOW INDEX FROM tbl_name to find out the name of the index. The name of the index is stored in the column called key_name in the results of that query.

Then you can use DROP INDEX:

DROP INDEX index_name ON tbl_name

or the ALTER TABLE syntax:

ALTER TABLE tbl_name DROP INDEX index_name

Insert null/empty value in sql datetime column by default

I was having the same issue this morning. It appears that for a DATE or DATETIME field, an empty value cannot be inserted. I got around this by first checking for an empty value (mydate = "") and if it was empty setting mydate = "NULL" before insert.

The DATE and DATETIME fields don't behave in the same way as VARCHAR fields.

Error HRESULT E_FAIL has been returned from a call to a COM component VS2012 when debugging

Maybe this page helps:

Scenario Two: The Microsoft Visual Studio 2010 IDE crashes while creating OR debugging a web application project. This above error occurs because of corrupted Cache of Visual Studio 2010. In order to resolve the issue just delete the project Cache from the below location:

C:\Program Files\Microsoft Visual Studio 10.0\Common7\IDE\ProjectTemplatesCache

C:\Program Files(x86)\Microsoft Visual Studio 10.0\Common7\IDE\ProjectTemplatesCache

Then run devenv.exe /setup to re-build the cache.

MySQL DAYOFWEEK() - my week begins with monday

Try to use the WEEKDAY() function.

Returns the weekday index for date (0 = Monday, 1 = Tuesday, … 6 = Sunday).

Count of "Defined" Array Elements

No, the only way to know how many elements are not undefined is to loop through and count them. That doesn't mean you have to write the loop, though, just that something, somewhere has to do it. (See #3 below for why I added that caveat.)

How you loop through and count them is up to you. There are lots of ways:

  1. A standard for loop from 0 to arr.length - 1 (inclusive).
  2. A for..in loop provided you take correct safeguards.
  3. Any of several of the new array features from ECMAScript5 (provided you're using a JavaScript engine that supports them, or you've included an ES5 shim, as they're all shim-able), like some, filter, or reduce, passing in an appropriate function. This is handy not only because you don't have to explicitly write the loop, but because using these features gives the JavaScript engine the opportunity to optimize the loop it does internally in various ways. (Whether it actually does will vary on the engine.)

...but it all amounts to looping, either explicitly or (in the case of the new array features) implicitly.

How do I add a simple onClick event handler to a canvas element?

You can also put DOM elements, like div on top of the canvas that would represent your canvas elements and be positioned the same way.

Now you can attach event listeners to these divs and run the necessary actions.

How do I refresh a DIV content?

Complete working code would look like this:

<script> 
$(document).ready(function(){
setInterval(function(){
      $("#here").load(window.location.href + " #here" );
}, 3000);
});
</script>

<div id="here">dynamic content ?</div>

self reloading div container refreshing every 3 sec.

jquery AJAX and json format

I never had any luck with that approach. I always do this (hope this helps):

var obj = {};

obj.first_name = $("#namec").val();
obj.last_name = $("#surnamec").val();
obj.email = $("#emailc").val();
obj.mobile = $("#numberc").val();
obj.password = $("#passwordc").val();

Then in your ajax:

$.ajax({
        type: "POST",
        url: hb_base_url + "consumer",
        contentType: "application/json",
        dataType: "json",
        data: JSON.stringify(obj),
        success: function(response) {
            console.log(response);
        },
        error: function(response) {
            console.log(response);
        }
    });

How to prevent scanf causing a buffer overflow in C?

Directly using scanf(3) and its variants poses a number of problems. Typically, users and non-interactive use cases are defined in terms of lines of input. It's rare to see a case where, if enough objects are not found, more lines will solve the problem, yet that's the default mode for scanf. (If a user didn't know to enter a number on the first line, a second and third line will probably not help.)

At least if you fgets(3) you know how many input lines your program will need, and you won't have any buffer overflows...

Oracle - How to create a readonly user

you can create user and grant privilege

create user read_only identified by read_only; grant create session,select any table to read_only;

How to set dropdown arrow in spinner?

One simple way is to wrap your Spinner + Drop Down Arrow Image inside a Layout. Set the background of Spinner as transparent so that the default arrow icon gets hidden. Something like this:

 <LinearLayout

        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/background"
        android:orientation="horizontal">

        <Spinner
            android:id="@+id/spinner"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:layout_weight="4"
            android:gravity="center"
            android:background="@android:color/transparent"
            android:spinnerMode="dropdown" />

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:layout_weight="1"
            android:onClick="showDropDown"
            android:src="@drawable/ic_chevron_down_blue" />

    </LinearLayout>

Here background.xml is a drawable to produce a box type background.

<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <solid android:color="@android:color/transparent" />
    <corners android:radius="2dp" />
    <stroke
        android:width="1dp"
        android:color="#BDBDBD" />
</shape>

The above code produces this type of a Spinner and icon.

Spinner with a custom drop down arrow

How to delete Project from Google Developers Console

As of this writing, it was necessary to:

  1. Select 'Manage all projects' from the dropdown list at the top of the Console page
  2. Click the delete button (trashcan icon) for the specific project on the project listing page

Class has no member named

I had similar problem. My header file which included the definition of the class wasn't working. I wasn't able to use the member functions of that class. So i simply copied my class to another header file. Now its working all ok.

Detecting real time window size changes in Angular 4

@HostListener("window:resize", [])
public onResize() {
  this.detectScreenSize();
}

public ngAfterViewInit() {
    this.detectScreenSize();
}

private detectScreenSize() {
    const height = window.innerHeight;
    const width = window.innerWidth;
}

Postman: How to make multiple requests at the same time

Postman doesn't do that but you can run multiple curl requests asynchronously in Bash:

curl url1 & curl url2 & curl url3 & ...

Remember to add an & after each request which means that request should run as an async job.

Postman however can generate curl snippet for your request: https://learning.getpostman.com/docs/postman/sending_api_requests/generate_code_snippets/

How to create Toast in Flutter?

For android original graphics toast you can use this: https://pub.dartlang.org/packages/fluttertoast

Works fine on Android and iOS. enter image description here

This version of the application is not configured for billing through Google Play

SOLUTION

Just hold on a while after uploading your app on play store because google takes some time to update app versions.It will work !

How do you stop tracking a remote branch in Git?

This is not an answer to the question, but I couldn't figure out how to get decent code formatting in a comment above... so auto-down-reputation-be-damned here's my comment.

I have the recipe submtted by @Dobes in a fancy shmancy [alias] entry in my .gitconfig:

# to untrack a local branch when I can't remember 'git config --unset'
cbr = "!f(){ git symbolic-ref -q HEAD 2>/dev/null | sed -e 's|refs/heads/||'; }; f"
bruntrack = "!f(){ br=${1:-`git cbr`};  \
    rm=`git config --get branch.$br.remote`; \
    tr=`git config --get branch.$br.merge`; \
    [ $rm:$tr = : ] && echo \"# untrack: not a tracking branch: $br\" && return 1; \
    git config --unset branch.$br.remote; git config --unset branch.$br.merge; \
    echo \"# untrack: branch $br no longer tracking $rm:$tr\"; return 0; }; f"

Then I can just run

$ git bruntrack branchname

If (Array.Length == 0)

This is the best way. Please note Array is an object in NET so you need to check for null before.

Regex remove all special characters except numbers?

If you don't mind including the underscore as an allowed character, you could try simply:

result = subject.replace(/\W+/g, "");

If the underscore must be excluded also, then

result = subject.replace(/[^A-Z0-9]+/ig, "");

(Note the case insensitive flag)

Dictionary text file

http://www.math.sjsu.edu/~foster/dictionary.txt

350,000 words

Very late, but might be useful for others.

Java RegEx meta character (.) and ordinary dot?

Escape special characters with a backslash. \., \*, \+, \\d, and so on. If you are unsure, you may escape any non-alphabetical character whether it is special or not. See the javadoc for java.util.regex.Pattern for further information.

Css pseudo classes input:not(disabled)not:[type="submit"]:focus

You have a few typos in your select. It should be: input:not([disabled]):not([type="submit"]):focus

See this jsFiddle for a proof of concept. On a sidenote, if I removed the "background-color" property, then the box shadow no longer works. Not sure why.

How can I undo a `git commit` locally and on a remote after `git push`

git reset --hard HEAD~1
git push -f <remote> <branch>

(Example push: git push -f origin bugfix/bug123)

This will undo the last commit and push the updated history to the remote. You need to pass the -f because you're replacing upstream history in the remote.

MATLAB, Filling in the area between two sets of data, lines in one figure

Building off of @gnovice's answer, you can actually create filled plots with shading only in the area between the two curves. Just use fill in conjunction with fliplr.

Example:

x=0:0.01:2*pi;                  %#initialize x array
y1=sin(x);                      %#create first curve
y2=sin(x)+.5;                   %#create second curve
X=[x,fliplr(x)];                %#create continuous x value array for plotting
Y=[y1,fliplr(y2)];              %#create y values for out and then back
fill(X,Y,'b');                  %#plot filled area

enter image description here

By flipping the x array and concatenating it with the original, you're going out, down, back, and then up to close both arrays in a complete, many-many-many-sided polygon.

Using Python's ftplib to get a directory listing, portably

There's no standard for the layout of the LIST response. You'd have to write code to handle the most popular layouts. I'd start with Linux ls and Windows Server DIR formats. There's a lot of variety out there, though.

Fall back to the nlst method (returning the result of the NLST command) if you can't parse the longer list. For bonus points, cheat: perhaps the longest number in the line containing a known file name is its length.

Replacing last character in a String with java

Try this:

s = s.replaceAll("[,]$", "");

stale element reference: element is not attached to the page document

This could be done in newer versions of selenium in JS( but all supporting stalenessOf will work):

 const { until } = require('selenium-webdriver');
 driver.wait(
        until.stalenessOf(
          driver.findElement(
            By.css(SQLQueriesByPhpMyAdminSelectors.sqlQueryArea)
          )
        ),
        5 * 1000
      )
      .then( driver.findElement(By.css(SQLQueriesByPhpMyAdminSelectors.sqlQueryArea))
      .sendKeys(sqlString)
  );

"unrecognized import path" with go get

Because GFW forbidden you to access golang.org ! And when i use the proxy , it can work well.

you can look at the information using command go get -v -u golang.org/x/oauth2

Creating a new dictionary in Python

Knowing how to write a preset dictionary is useful to know as well:

cmap =  {'US':'USA','GB':'Great Britain'}

# Explicitly:
# -----------
def cxlate(country):
    try:
        ret = cmap[country]
    except KeyError:
        ret = '?'
    return ret

present = 'US' # this one is in the dict
missing = 'RU' # this one is not

print cxlate(present) # == USA
print cxlate(missing) # == ?

# or, much more simply as suggested below:

print cmap.get(present,'?') # == USA
print cmap.get(missing,'?') # == ?

# with country codes, you might prefer to return the original on failure:

print cmap.get(present,present) # == USA
print cmap.get(missing,missing) # == RU

PHP, How to get current date in certain format

date("Y-m-d H:i:s"); // This should do it.

Why does C++ code for testing the Collatz conjecture run faster than hand-written assembly?

On a rather unrelated note: more performance hacks!

  • [the first «conjecture» has been finally debunked by @ShreevatsaR; removed]

  • When traversing the sequence, we can only get 3 possible cases in the 2-neighborhood of the current element N (shown first):

    1. [even] [odd]
    2. [odd] [even]
    3. [even] [even]

    To leap past these 2 elements means to compute (N >> 1) + N + 1, ((N << 1) + N + 1) >> 1 and N >> 2, respectively.

    Let`s prove that for both cases (1) and (2) it is possible to use the first formula, (N >> 1) + N + 1.

    Case (1) is obvious. Case (2) implies (N & 1) == 1, so if we assume (without loss of generality) that N is 2-bit long and its bits are ba from most- to least-significant, then a = 1, and the following holds:

    (N << 1) + N + 1:     (N >> 1) + N + 1:
    
            b10                    b1
             b1                     b
           +  1                   + 1
           ----                   ---
           bBb0                   bBb
    

    where B = !b. Right-shifting the first result gives us exactly what we want.

    Q.E.D.: (N & 1) == 1 ? (N >> 1) + N + 1 == ((N << 1) + N + 1) >> 1.

    As proven, we can traverse the sequence 2 elements at a time, using a single ternary operation. Another 2× time reduction.

The resulting algorithm looks like this:

uint64_t sequence(uint64_t size, uint64_t *path) {
    uint64_t n, i, c, maxi = 0, maxc = 0;

    for (n = i = (size - 1) | 1; i > 2; n = i -= 2) {
        c = 2;
        while ((n = ((n & 3)? (n >> 1) + n + 1 : (n >> 2))) > 2)
            c += 2;
        if (n == 2)
            c++;
        if (c > maxc) {
            maxi = i;
            maxc = c;
        }
    }
    *path = maxc;
    return maxi;
}

int main() {
    uint64_t maxi, maxc;

    maxi = sequence(1000000, &maxc);
    printf("%llu, %llu\n", maxi, maxc);
    return 0;
}

Here we compare n > 2 because the process may stop at 2 instead of 1 if the total length of the sequence is odd.

[EDIT:]

Let`s translate this into assembly!

MOV RCX, 1000000;



DEC RCX;
AND RCX, -2;
XOR RAX, RAX;
MOV RBX, RAX;

@main:
  XOR RSI, RSI;
  LEA RDI, [RCX + 1];

  @loop:
    ADD RSI, 2;
    LEA RDX, [RDI + RDI*2 + 2];
    SHR RDX, 1;
    SHRD RDI, RDI, 2;    ror rdi,2   would do the same thing
    CMOVL RDI, RDX;      Note that SHRD leaves OF = undefined with count>1, and this doesn't work on all CPUs.
    CMOVS RDI, RDX;
    CMP RDI, 2;
  JA @loop;

  LEA RDX, [RSI + 1];
  CMOVE RSI, RDX;

  CMP RAX, RSI;
  CMOVB RAX, RSI;
  CMOVB RBX, RCX;

  SUB RCX, 2;
JA @main;



MOV RDI, RCX;
ADD RCX, 10;
PUSH RDI;
PUSH RCX;

@itoa:
  XOR RDX, RDX;
  DIV RCX;
  ADD RDX, '0';
  PUSH RDX;
  TEST RAX, RAX;
JNE @itoa;

  PUSH RCX;
  LEA RAX, [RBX + 1];
  TEST RBX, RBX;
  MOV RBX, RDI;
JNE @itoa;

POP RCX;
INC RDI;
MOV RDX, RDI;

@outp:
  MOV RSI, RSP;
  MOV RAX, RDI;
  SYSCALL;
  POP RAX;
  TEST RAX, RAX;
JNE @outp;

LEA RAX, [RDI + 59];
DEC RDI;
SYSCALL;

Use these commands to compile:

nasm -f elf64 file.asm
ld -o file file.o

See the C and an improved/bugfixed version of the asm by Peter Cordes on Godbolt. (editor's note: Sorry for putting my stuff in your answer, but my answer hit the 30k char limit from Godbolt links + text!)

How to use <md-icon> in Angular Material?

In their latest release there's a directive called md-icon

<md-icon icon="img/icons/ic_refresh_24px.svg"></md-icon>

What is the 'pythonic' equivalent to the 'fold' function from functional programming?

The actual answer to this (reduce) problem is: Just use a loop!

initial_value = 0
for x in the_list:
    initial_value += x #or any function.

This will be faster than a reduce and things like PyPy can optimize loops like that.

BTW, the sum case should be solved with the sum function

Android ImageButton with a selected state?

This works for me:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <!-- NOTE: order is important (the first matching state(s) is what is rendered) -->
    <item 
        android:state_selected="true" 
        android:drawable="@drawable/info_icon_solid_with_shadow" />
    <item 
        android:drawable="@drawable/info_icon_outline_with_shadow" />
 </selector>

And then in java:

//assign the image in code (or you can do this in your layout xml with the src attribute)
imageButton.setImageDrawable(getBaseContext().getResources().getDrawable(R.drawable....));

//set the click listener
imageButton.setOnClickListener(new OnClickListener() {

    public void onClick(View button) {
        //Set the button's appearance
        button.setSelected(!button.isSelected());

        if (button.isSelected()) {
            //Handle selected state change
        } else {
            //Handle de-select state change
        }

    }

});

For smooth transition you can also mention animation time:

<selector xmlns:android="http://schemas.android.com/apk/res/android" android:exitFadeDuration="@android:integer/config_mediumAnimTime">

Setting a minimum/maximum character count for any character using a regular expression

If you want to set Min 1 count and no Max length,

^.{1,}$

Two arrays in foreach loop

foreach( $codes as $code and $names as $name ) { }

That is not valid.

You probably want something like this...

foreach( $codes as $index => $code ) {
   echo '<option value="' . $code . '">' . $names[$index] . '</option>';
}

Alternatively, it'd be much easier to make the codes the key of your $names array...

$names = array(
   'tn' => 'Tunisia',
   'us' => 'United States',
   ...
);

What's the best way to add a drop shadow to my UIView

So yes, you should prefer the shadowPath property for performance, but also: From the header file of CALayer.shadowPath

Specifying the path explicitly using this property will usually * improve rendering performance, as will sharing the same path * reference across multiple layers

A lesser known trick is sharing the same reference across multiple layers. Of course they have to use the same shape, but this is common with table/collection view cells.

I don't know why it gets faster if you share instances, i'm guessing it caches the rendering of the shadow and can reuse it for other instances in the view. I wonder if this is even faster with

Can I have H2 autocreate a schema in an in-memory database?

What Thomas has written is correct, in addition to that, if you want to initialize multiple schemas you can use the following. Note there is a \\; separating the two create statements.

    EmbeddedDatabase db = new EmbeddedDatabaseBuilder()
                    .setType(EmbeddedDatabaseType.H2)
                    .setName("testDb;DB_CLOSE_ON_EXIT=FALSE;MODE=Oracle;INIT=create " +
                            "schema if not exists " +
                            "schema_a\\;create schema if not exists schema_b;" +
                            "DB_CLOSE_DELAY=-1;")
                    .addScript("sql/provPlan/createTable.sql")
                    .addScript("sql/provPlan/insertData.sql")
                    .addScript("sql/provPlan/insertSpecRel.sql")
                    .build();

ref : http://www.h2database.com/html/features.html#execute_sql_on_connection

Disable dragging an image from an HTML page

<img draggable="false" src="images/testimg1.jpg" alt=""/>

How do I programmatically set the value of a select box element using JavaScript?

Suppose your form is named form1:

function selectValue(val)
{
  var lc = document.form1.leaveCode;
  for (i=0; i&lt;lc.length; i++)
  {
    if (lc.options[i].value == val)
    {
        lc.selectedIndex = i;
        return;
    }
  }
}

Python class returning value

the worked proposition for me is __call__ on class who create list of little numbers:

import itertools
    
class SmallNumbers:
    def __init__(self, how_much):
        self.how_much = int(how_much)
        self.work_list = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9']
        self.generated_list = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9']
        start = 10
        end = 100
        for cmb in range(2, len(str(self.how_much)) + 1):
            self.ListOfCombinations(is_upper_then=start, is_under_then=end, combinations=cmb)
            start *= 10
            end *= 10

    def __call__(self, number, *args, **kwargs):
        return self.generated_list[number]

    def ListOfCombinations(self, is_upper_then, is_under_then, combinations):
        multi_work_list = eval(str('self.work_list,') * combinations)
        nbr = 0
        for subset in itertools.product(*multi_work_list):
            if is_upper_then <= nbr < is_under_then:
                self.generated_list.append(''.join(subset))
                if self.how_much == nbr:
                    break
            nbr += 1

and to run it:

if __name__ == '__main__':
        sm = SmallNumbers(56)
        print(sm.generated_list)
        print(sm.generated_list[34], sm.generated_list[27], sm.generated_list[10])
        print('The Best', sm(15), sm(55), sm(49), sm(0))

result

['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12', '13', '14', '15', '16', '17', '18', '19', '20', '21', '22', '23', '24', '25', '26', '27', '28', '29', '30', '31', '32', '33', '34', '35', '36', '37', '38', '39', '40', '41', '42', '43', '44', '45', '46', '47', '48', '49', '50', '51', '52', '53', '54', '55', '56']
34 27 10
The Best 15 55 49 0

Return HTTP status code 201 in flask

In my case I had to combine the above in order to make it work

return Response(json.dumps({'Error': 'Error in payload'}), 
status=422, 
mimetype="application/json")

How do you specify the Java compiler version in a pom.xml file?

I faced same issue in eclipse neon simple maven java project

But I add below details inside pom.xml file

   <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.6.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

After right click on project > maven > update project (checked force update)

Its resolve me to display error on project

Hope it's will helpful

Thansk

Angular JS - angular.forEach - How to get key of the object?

The first parameter to the iterator in forEach is the value and second is the key of the object.

angular.forEach(objectToIterate, function(value, key) {
    /* do something for all key: value pairs */
});

In your example, the outer forEach is actually:

angular.forEach($scope.filters, function(filterObj , filterKey)

Why can't Python import Image from PIL?

I had the same issue, and did this to fix it:

  1. In command prompt

    pip install Pillow ##
    
  2. Ensure that you use

    from PIL import Image
    

I in Image has to be capital. That was the issue in my case.

How to Merge Two Eloquent Collections?

Merge two different eloquent collections into one and some objects happen to have the same id, one will overwrite the other. Use push() method instead or rethink your approach to the problem to avoid that. Refer to web

Convert string to number field

Within Crystal, you can do it by creating a formula that uses the ToNumber function. It might be a good idea to code for the possibility that the field might include non-numeric data - like so:

If NumericText ({field}) then ToNumber ({field}) else 0

Alternatively, you might find it easier to convert the field's datatype within the query used in the report.

Print "hello world" every X seconds

Use java.util.Timer and Timer#schedule(TimerTask,delay,period) method will help you.

public class RemindTask extends TimerTask {
    public void run() {
      System.out.println(" Hello World!");
    }
    public static void main(String[] args){
       Timer timer = new Timer();
       timer.schedule(new RemindTask(), 3000,3000);
    }
  }

Check whether a string matches a regex in JS

Use /youregexp/.test(yourString) if you only want to know whether your string matches the regexp.

How to print an exception in Python 3?

[In Python3]

Let's say you want to handle an IndexError and print the traceback, you can do the following:

from traceback import print_tb 
empty_list = [] 
try: 
    x = empty_list[100]
except IndexError as index_error: 
    print_tb(index_error.__traceback__)

Note: You can use the format_tb function instead of print_tb to get the traceback as a string for logging purposes. Hope this helps.

Django 1.7 throws django.core.exceptions.AppRegistryNotReady: Models aren't loaded yet

Running these commands solved my problem (credit to this answer):

import django
django.setup()

However I'm not sure why I need this. Comments would be appreciated.

Get week of year in JavaScript like in PHP

Jacob Wright's Date.format() library implements date formatting in the style of PHP's date() function and supports the ISO-8601 week number:

new Date().format('W');

It may be a bit overkill for just a week number, but it does support PHP style formatting and is quite handy if you'll be doing a lot of this.

How does database indexing work?

Just a quick suggestion.. As indexing costs you additional writes and storage space, so if your application requires more insert/update operation, you might want to use tables without indexes, but if it requires more data retrieval operations, you should go for indexed table.

How to add parameters to HttpURLConnection using POST using NameValuePair

If it's not too late, I'd like to share my code

Utils.java:

public static String buildPostParameters(Object content) {
        String output = null;
        if ((content instanceof String) ||
                (content instanceof JSONObject) ||
                (content instanceof JSONArray)) {
            output = content.toString();
        } else if (content instanceof Map) {
            Uri.Builder builder = new Uri.Builder();
            HashMap hashMap = (HashMap) content;
            if (hashMap != null) {
                Iterator entries = hashMap.entrySet().iterator();
                while (entries.hasNext()) {
                    Map.Entry entry = (Map.Entry) entries.next();
                    builder.appendQueryParameter(entry.getKey().toString(), entry.getValue().toString());
                    entries.remove(); // avoids a ConcurrentModificationException
                }
                output = builder.build().getEncodedQuery();
            }
        }

        return output;
    }

public static URLConnection makeRequest(String method, String apiAddress, String accessToken, String mimeType, String requestBody) throws IOException {
        URL url = new URL(apiAddress);
        HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

        urlConnection.setDoInput(true);
        urlConnection.setDoOutput(!method.equals("GET"));
        urlConnection.setRequestMethod(method);

        urlConnection.setRequestProperty("Authorization", "Bearer " + accessToken);        

        urlConnection.setRequestProperty("Content-Type", mimeType);
        OutputStream outputStream = new BufferedOutputStream(urlConnection.getOutputStream());
        BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream, "utf-8"));
        writer.write(requestBody);
        writer.flush();
        writer.close();
        outputStream.close();            

        urlConnection.connect();

        return urlConnection;
    }

MainActivity.java:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    new APIRequest().execute();
}

private class APIRequest extends AsyncTask<Void, Void, String> {

        @Override
        protected Object doInBackground(Void... params) {

            // Of course, you should comment the other CASES when testing one CASE

            // CASE 1: For FromBody parameter
            String url = "http://10.0.2.2/api/frombody";
            String requestBody = Utils.buildPostParameters("'FromBody Value'"); // must have '' for FromBody parameter
            HttpURLConnection urlConnection = null;
            try {
                urlConnection = (HttpURLConnection) Utils.makeRequest("POST", url, null, "application/json", requestBody);                    
                InputStream inputStream;
                // get stream
                if (urlConnection.getResponseCode() < HttpURLConnection.HTTP_BAD_REQUEST) {
                    inputStream = urlConnection.getInputStream();
                } else {
                    inputStream = urlConnection.getErrorStream();
                }
                // parse stream
                BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
                String temp, response = "";
                while ((temp = bufferedReader.readLine()) != null) {
                    response += temp;
                }
                return response;
            } catch (IOException e) {
                e.printStackTrace();
                return e.toString();
            } finally {
                if (urlConnection != null) {
                    urlConnection.disconnect();
                }
            }

            // CASE 2: For JSONObject parameter
            String url = "http://10.0.2.2/api/testjsonobject";
            JSONObject jsonBody;
            String requestBody;
            HttpURLConnection urlConnection;
            try {
                jsonBody = new JSONObject();
                jsonBody.put("Title", "BNK Title");
                jsonBody.put("Author", "BNK");
                jsonBody.put("Date", "2015/08/08");
                requestBody = Utils.buildPostParameters(jsonBody);
                urlConnection = (HttpURLConnection) Utils.makeRequest("POST", url, null, "application/json", requestBody);                    
                ...
                // the same logic to case #1
                ...
                return response;
            } catch (JSONException | IOException e) {
                e.printStackTrace();
                return e.toString();
            } finally {
                if (urlConnection != null) {
                    urlConnection.disconnect();
                }
            }           

            // CASE 3: For form-urlencoded parameter
            String url = "http://10.0.2.2/api/token";
            HttpURLConnection urlConnection;
            Map<String, String> stringMap = new HashMap<>();
            stringMap.put("grant_type", "password");
            stringMap.put("username", "username");
            stringMap.put("password", "password");
            String requestBody = Utils.buildPostParameters(stringMap);
            try {
                urlConnection = (HttpURLConnection) Utils.makeRequest("POST", url, null, "application/x-www-form-urlencoded", requestBody);
                ...
                // the same logic to case #1
                ...
                return response;
            } catch (Exception e) {
                e.printStackTrace();
                return e.toString();
            } finally {
                if (urlConnection != null) {
                    urlConnection.disconnect();
                }
            }                  
        }

        @Override
        protected void onPostExecute(String response) {
            super.onPostExecute(response);
            // do something...
        }
    }

python save image from url

Python3

import urllib.request
print('Beginning file download with urllib2...')
url = 'https://akm-img-a-in.tosshub.com/sites/btmt/images/stories/modi_instagram_660_020320092717.jpg'
urllib.request.urlretrieve(url, 'modiji.jpg')

Deleting all files from a folder using PHP?

If you want to delete everything from folder (including subfolders) use this combination of array_map, unlink and glob:

array_map( 'unlink', array_filter((array) glob("path/to/temp/*") ) );

This call can also handle empty directories ( thanks for the tip, @mojuba!)

C++ convert from 1 char to string?

I honestly thought that the casting method would work fine. Since it doesn't you can try stringstream. An example is below:

#include <sstream>
#include <string>
std::stringstream ss;
std::string target;
char mychar = 'a';
ss << mychar;
ss >> target;

How to save data in an android app

You have two options, and I'll leave selection up to you.

  1. Shared Preferences

    This is a framework unique to Android that allows you to store primitive values (such as int, boolean, and String, although strictly speaking String isn't a primitive) in a key-value framework. This means that you give a value a name, say, "homeScore" and store the value to this key.

    SharedPreferences settings = getApplicationContext().getSharedPreferences(PREFS_NAME, 0);
    SharedPreferences.Editor editor = settings.edit();
    editor.putInt("homeScore", YOUR_HOME_SCORE);
    
    // Apply the edits!
    editor.apply();
    
    // Get from the SharedPreferences
    SharedPreferences settings = getApplicationContext().getSharedPreferences(PREFS_NAME, 0);
    int homeScore = settings.getInt("homeScore", 0);
    
  2. Internal Storage

    This, in my opinion, is what you might be looking for. You can store anything you want to a file, so this gives you more flexibility. However, the process can be trickier because everything will be stored as bytes, and that means you have to be careful to keep your read and write processes working together.

    int homeScore;
    byte[] homeScoreBytes;
    
    homeScoreBytes[0] = (byte) homeScore;
    homeScoreBytes[1] = (byte) (homeScore >> 8);  //you can probably skip these two 
    homeScoreBytes[2] = (byte) (homeScore >> 16); //lines, because I've never seen a                   
                                                  //basketball score above 128, it's
                                                  //such a rare occurance.
    
    FileOutputStream outputStream = getApplicationContext().openFileOutput(FILENAME, Context.MODE_PRIVATE);
    outputStream.write(homeScoreBytes);
    outputStream.close();
    

Now, you can also look into External Storage, but I don't recommend that in this particular case, because the external storage might not be there later. (Note that if you pick this, it requires a permission)

How can I use Html.Action?

first, create a class to hold your parameters:

public class PkRk {
    public int pk { get; set; }
    public int rk { get; set; }
}

then, use the Html.Action passing the parameters:

Html.Action("PkRkAction", new { pkrk = new PkRk { pk=400, rk=500} })

and use in Controller:

public ActionResult PkRkAction(PkRk pkrk) {
    return PartialView(pkrk);
}

ERROR 403 in loading resources like CSS and JS in my index.php

You need to change permissions on the folder bootstrap/css. Your super user may be able to access it but it doesn't mean apache or nginx have access to it, that's why you still need to change the permissions.

Tip: I usually make the apache/nginx's user group owner of that kind of folders and give 775 permission to it.

Copy or rsync command

if you are using cp doesn't save existing files when copying folders of the same name. Lets say you have this folders:

/myFolder
  someTextFile.txt

/someOtherFolder
  /myFolder
    wellHelloThere.txt

Then you copy one over the other:

cp /someOtherFolder/myFolder /myFolder

result:

/myFolder
  wellHelloThere.txt

This is at least what happens on macOS and I wanted to preserve the diff files so I used rsync.

Maven dependency update on commandline

Simple run your project online i.e mvn clean install . It fetches all the latest dependencies that you mention in your pom.xml and built the project

Efficient way of having a function only execute once in a loop

I've taken a more flexible approach inspired by functools.partial function:

DO_ONCE_MEMORY = []

def do_once(id, func, *args, **kwargs):
    if id not in DO_ONCE_MEMORY:
        DO_ONCE_MEMORY.append(id)
        return func(*args, **kwargs)
    else:
        return None

With this approach you are able to have more complex and explicit interactions:

do_once('foobar', print, "first try")
do_once('foo', print, "first try")
do_once('bar', print, "second try")
# first try 
# second try 

The exciting part about this approach it can be used anywhere and does not require factories - it's just a small memory tracker.

Change IPython/Jupyter notebook working directory

Simply follow the guide on the official site, also copied below. For the first step, instead of copying the launcher, you can just go to start menu and right click to open the location.

  1. Copy the Jupyter Notebook launcher from the menu to the desktop.

  2. Right click on the new launcher and change the “Start in” field by pasting the full path of the folder which will contain all the notebooks.

  3. Double-click on the Jupyter Notebook desktop launcher (icon shows [IPy]) to start the Jupyter Notebook App, which will open in a new browser window (or tab). Note also that a secondary terminal window (used only for error logging and for shut down) will be also opened. If only the terminal starts, try opening this address with your browser: http://localhost:8888/.

android.widget.Switch - on/off event listener?

You can use DataBinding and ViewModel for Switch Checked Change event

<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools">

    <data>

        <variable
                name="viewModel"
                type="com.example.ui.ViewModel" />
    </data>
    <Switch
            android:id="@+id/on_off_switch"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onCheckedChanged="@{(button, on) -> viewModel.onCheckedChange(on)}"
     />

CreateProcess: No such file or directory

This problem might arise if you have different versions of programs.

For instance, you have 1-year old gcc and you want to compile a C++ source code. If you use mingw-get to install g++, gcc and g++ will suddenly have different versions and you ware likely to find yourself in this situation.

Running mingw-get update and mingw-get upgrade has solved this issue for me.

How to make an input type=button act like a hyperlink and redirect using a get request?

I think that is your need.

a href="#" onclick="document.forms[0].submit();return false;"

HTML 5 Video "autoplay" not automatically starting in CHROME

Try this when i tried giving muted , check this demo in codpen

    <video width="320" height="240" controls autoplay muted id="videoId">
  <source src="http://techslides.com/demos/sample-videos/small.mp4" type="video/mp4">
  Your browser does not support the video tag.
</video>

script

function toggleMute() {

  var video=document.getElementById("videoId");

  if(video.muted){
    video.muted = false;
  } else {
    debugger;
    video.muted = true;
    video.play()
  }

}

$(document).ready(function(){
  setTimeout(toggleMute,3000);
})

edited attribute content

autoplay muted playsinline

https://developers.google.com/web/updates/2017/09/autoplay-policy-changes

React - clearing an input value after form submit

In your onHandleSubmit function, set your state to {city: ''} again like this :

this.setState({ city: '' });

SQL Server 2008- Get table constraints

You should use the current sys catalog views (if you're on SQL Server 2005 or newer - the sysobjects views are deprecated and should be avoided) - check out the extensive MSDN SQL Server Books Online documentation on catalog views here.

There are quite a few views you might be interested in:

  • sys.default_constraints for default constraints on columns
  • sys.check_constraints for check constraints on columns
  • sys.key_constraints for key constraints (e.g. primary keys)
  • sys.foreign_keys for foreign key relations

and a lot more - check it out!

You can query and join those views to get the info needed - e.g. this will list the tables, columns and all default constraints defined on them:

SELECT 
    TableName = t.Name,
    ColumnName = c.Name,
    dc.Name,
    dc.definition
FROM sys.tables t
INNER JOIN sys.default_constraints dc ON t.object_id = dc.parent_object_id
INNER JOIN sys.columns c ON dc.parent_object_id = c.object_id AND c.column_id = dc.parent_column_id
ORDER BY t.Name

Return Result from Select Query in stored procedure to a List

 SqlConnection connection = new SqlConnection(ConnectionString);

 command = new SqlCommand("TestProcedure", connection);
 command.CommandType = System.Data.CommandType.StoredProcedure;

 connection.Open();

 DataTable dt = new DataTable();

 dt.Load(command.ExecuteReader());

 gvGrid.DataSource = dt;
 gvGrid.DataBind();

html - table row like a link

I made myself a custom jquery function:

Html

<tr data-href="site.com/whatever">

jQuery

$('tr[data-href]').on("click", function() {
    document.location = $(this).data('href');
});

Easy and perfect for me. Hopefully it helps you.

(I know OP want CSS and HTML only, but consider jQuery)

Edit

Agreed with Matt Kantor using data attr. Edited answer above

Hibernate: "Field 'id' doesn't have a default value"

I had the same problem. I found the tutorial Hibernate One-To-One Mapping Example using Foreign key Annotation and followed it step by step like below:

Create database table with this script:

create table ADDRESS (
   id INT(11) NOT NULL AUTO_INCREMENT,
   street VARCHAR(250) NOT NULL,
   city  VARCHAR(100) NOT NULL,
   country  VARCHAR(100) NOT NULL,
   PRIMARY KEY (id)
);

create table STUDENT (
    id            INT(11) NOT NULL AUTO_INCREMENT, 
    name          VARCHAR(100) NOT NULL, 
    entering_date DATE NOT NULL, 
    nationality   TEXT NOT NULL, 
    code          VARCHAR(30) NOT NULL,
    address_id INT(11) NOT NULL,
    PRIMARY KEY (id),
    CONSTRAINT student_address FOREIGN KEY (address_id) REFERENCES ADDRESS (id)   
);

Here is the entities with the above tables

@Entity
@Table(name = "STUDENT")
public class Student implements Serializable {

    private static final long serialVersionUID = 6832006422622219737L;

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;

 }

@Entity
@Table(name = "ADDRESS")
public class Address {

    @Id @GeneratedValue
    @Column(name = "ID")
    private long id;
}

The problem was resolved.

Notice: The primary key must be set to AUTO_INCREMENT

Open two instances of a file in a single Visual Studio session

When working with Visual Studio 2013 and VB.NET I found that you can quite easily customize the menu and add the "New Window" command - there is no need to mess with the registry!

God only knows why Microsoft chose not to include the command for some languages...?

PL/SQL print out ref cursor returned by a stored procedure

You can use a bind variable at the SQLPlus level to do this. Of course you have little control over the formatting of the output.

VAR x REFCURSOR;
EXEC GetGrantListByPI(args, :x);
PRINT x;

How to select distinct query using symfony2 doctrine query builder?

you could write

select DISTINCT f from t;

as

select f from t group by f;

thing is, I am just currently myself getting into Doctrine, so I cannot give you a real answer. but you could as shown above, simulate a distinct with group by and transform that into Doctrine. if you want add further filtering then use HAVING after group by.

PHP Fatal error: Cannot redeclare class

It actually means that class is already declared in the page and you are trying to recreate it.

A simple technique is as follow.

I solved the issue with the following. Hope this will help you a bit.

if(!class_exists("testClassIfExist"))
{
    require_once("testClassIfExist.php");
}

How to change the scrollbar color using css

You can use the following attributes for webkit, which reach into the shadow DOM:

::-webkit-scrollbar              { /* 1 */ }
::-webkit-scrollbar-button       { /* 2 */ }
::-webkit-scrollbar-track        { /* 3 */ }
::-webkit-scrollbar-track-piece  { /* 4 */ }
::-webkit-scrollbar-thumb        { /* 5 */ }
::-webkit-scrollbar-corner       { /* 6 */ }
::-webkit-resizer                { /* 7 */ }

Here's a working fiddle with a red scrollbar, based on code from this page explaining the issues.

http://jsfiddle.net/hmartiro/Xck2A/1/

Using this and your solution, you can handle all browsers except Firefox, which at this point I think still requires a javascript solution.

Why call git branch --unset-upstream to fixup?

delete your local branch by following command

git branch -d branch_name

you could also do

git branch -D branch_name 

which basically force a delete (even if local not merged to source)

Mongodb find() query : return only unique values (no duplicates)

I think you can use db.collection.distinct(fields,query)

You will be able to get the distinct values in your case for NetworkID.

It should be something like this :

Db.collection.distinct('NetworkID')

"&" meaning after variable type

The & means that the function accepts the address (or reference) to a variable, instead of the value of the variable.

For example, note the difference between this:

void af(int& g)
{
    g++;
    cout<<g;
}

int main()
{
    int g = 123;
    cout << g;
    af(g);
    cout << g;
    return 0;
}

And this (without the &):

void af(int g)
{
    g++;
    cout<<g;
}

int main()
{
    int g = 123;
    cout << g;
    af(g);
    cout << g;
    return 0;
}

Passing a method parameter using Task.Factory.StartNew

For passing a single integer I agree with Reed Copsey's answer. If in the future you are going to pass more complicated constucts I personally like to pass all my variables as an Anonymous Type. It will look something like this:

foreach(int id in myIdsToCheck)
{
    Task.Factory.StartNew( (Object obj) => 
        {
           var data = (dynamic)obj;
           CheckFiles(data.id, theBlockingCollection,
               cancelCheckFile.Token, 
               TaskCreationOptions.LongRunning, 
               TaskScheduler.Default);
        }, new { id = id }); // Parameter value
}

You can learn more about it in my blog

What is the difference between user and kernel modes in operating systems?

A processor in a computer running Windows has two different modes: user mode and kernel mode. The processor switches between the two modes depending on what type of code is running on the processor. Applications run in user mode, and core operating system components run in kernel mode. While many drivers run in kernel mode, some drivers may run in user mode.

When you start a user-mode application, Windows creates a process for the application. The process provides the application with a private virtual address space and a private handle table. Because an application's virtual address space is private, one application cannot alter data that belongs to another application. Each application runs in isolation, and if an application crashes, the crash is limited to that one application. Other applications and the operating system are not affected by the crash.

In addition to being private, the virtual address space of a user-mode application is limited. A processor running in user mode cannot access virtual addresses that are reserved for the operating system. Limiting the virtual address space of a user-mode application prevents the application from altering, and possibly damaging, critical operating system data.

All code that runs in kernel mode shares a single virtual address space. This means that a kernel-mode driver is not isolated from other drivers and the operating system itself. If a kernel-mode driver accidentally writes to the wrong virtual address, data that belongs to the operating system or another driver could be compromised. If a kernel-mode driver crashes, the entire operating system crashes.

If you are a Windows user once go through this link you will get more.

Communication between user mode and kernel mode

How to use bluetooth to connect two iPhone?

You can connect two iPhones and transfer data via Bluetooth using either the high-level GameKit framework or the lower-level (but still easy to work with) Bonjour discovery mechanisms. Bonjour also works transparently between Bluetooth and WiFi on the iPhone under 3.0, so it's a good choice if you would like to support iPhone-to-iPhone data transfers on those two types of networks.

For more information, you can also look at the responses to these questions:

Using multiple property files (via PropertyPlaceholderConfigurer) in multiple projects/modules

I know that this is an old question, but the ignore-unresolvable property was not working for me and I didn't know why.

The problem was that I needed an external resource (something like location="file:${CATALINA_HOME}/conf/db-override.properties") and the ignore-unresolvable="true" does not do the job in this case.

What one needs to do for ignoring a missing external resource is:

ignore-resource-not-found="true"

Just in case anyone else bumps into this.

How to convert Blob to File in JavaScript

For me to work I had to explicitly provide the type although it is contained in the blob by doing so:

const file = new File([blob], 'untitled', { type: blob.type })

Disable firefox same origin policy

I wrote an add-on to overcome this issue in Firefox (Chrome, Opera version will have soon). It works with the latest Firefox version, with beautiful UI and support JS regex: https://addons.mozilla.org/en-US/firefox/addon/cross-domain-cors

enter image description here

Using :before and :after CSS selector to insert Html

content doesn't support HTML, only text. You should probably use javascript, jQuery or something like that.

Another problem with your code is " inside a " block. You should mix ' and " (class='headingDetail').

If content did support HTML you could end up in an infinite loop where content is added inside content.

How to get am pm from the date time string using moment js

You are using the wrong format tokens when parsing your input. You should use ddd for an abbreviation of the name of day of the week, DD for day of the month, MMM for an abbreviation of the month's name, YYYY for the year, hh for the 1-12 hour, mm for minutes and A for AM/PM. See moment(String, String) docs.

Here is a working live sample:

_x000D_
_x000D_
console.log( moment('Mon 03-Jul-2017, 11:00 AM', 'ddd DD-MMM-YYYY, hh:mm A').format('hh:mm A') );_x000D_
console.log( moment('Mon 03-Jul-2017, 11:00 PM', 'ddd DD-MMM-YYYY, hh:mm A').format('hh:mm A') );
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.18.1/moment.min.js"></script>
_x000D_
_x000D_
_x000D_

UITextView that expands to text using auto layout

I've found it's not entirely uncommon in situations where you may still need isScrollEnabled set to true to allow a reasonable UI interaction. A simple case for this is when you want to allow an auto expanding text view but still limit it's maximum height to something reasonable in a UITableView.

Here's a subclass of UITextView I've come up with that allows auto expansion with auto layout but that you could still constrain to a maximum height and which will manage whether the view is scrollable depending on the height. By default the view will expand indefinitely if you have your constraints setup that way.

import UIKit

class FlexibleTextView: UITextView {
    // limit the height of expansion per intrinsicContentSize
    var maxHeight: CGFloat = 0.0
    private let placeholderTextView: UITextView = {
        let tv = UITextView()

        tv.translatesAutoresizingMaskIntoConstraints = false
        tv.backgroundColor = .clear
        tv.isScrollEnabled = false
        tv.textColor = .disabledTextColor
        tv.isUserInteractionEnabled = false
        return tv
    }()
    var placeholder: String? {
        get {
            return placeholderTextView.text
        }
        set {
            placeholderTextView.text = newValue
        }
    }

    override init(frame: CGRect, textContainer: NSTextContainer?) {
        super.init(frame: frame, textContainer: textContainer)
        isScrollEnabled = false
        autoresizingMask = [.flexibleWidth, .flexibleHeight]
        NotificationCenter.default.addObserver(self, selector: #selector(UITextInputDelegate.textDidChange(_:)), name: Notification.Name.UITextViewTextDidChange, object: self)
        placeholderTextView.font = font
        addSubview(placeholderTextView)

        NSLayoutConstraint.activate([
            placeholderTextView.leadingAnchor.constraint(equalTo: leadingAnchor),
            placeholderTextView.trailingAnchor.constraint(equalTo: trailingAnchor),
            placeholderTextView.topAnchor.constraint(equalTo: topAnchor),
            placeholderTextView.bottomAnchor.constraint(equalTo: bottomAnchor),
        ])
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    override var text: String! {
        didSet {
            invalidateIntrinsicContentSize()
            placeholderTextView.isHidden = !text.isEmpty
        }
    }

    override var font: UIFont? {
        didSet {
            placeholderTextView.font = font
            invalidateIntrinsicContentSize()
        }
    }

    override var contentInset: UIEdgeInsets {
        didSet {
            placeholderTextView.contentInset = contentInset
        }
    }

    override var intrinsicContentSize: CGSize {
        var size = super.intrinsicContentSize

        if size.height == UIViewNoIntrinsicMetric {
            // force layout
            layoutManager.glyphRange(for: textContainer)
            size.height = layoutManager.usedRect(for: textContainer).height + textContainerInset.top + textContainerInset.bottom
        }

        if maxHeight > 0.0 && size.height > maxHeight {
            size.height = maxHeight

            if !isScrollEnabled {
                isScrollEnabled = true
            }
        } else if isScrollEnabled {
            isScrollEnabled = false
        }

        return size
    }

    @objc private func textDidChange(_ note: Notification) {
        // needed incase isScrollEnabled is set to true which stops automatically calling invalidateIntrinsicContentSize()
        invalidateIntrinsicContentSize()
        placeholderTextView.isHidden = !text.isEmpty
    }
}

As a bonus there's support for including placeholder text similar to UILabel.

I need an unordered list without any bullets

This orders a list vertically without bullet points. In just one line!

li {
    display: block;
}

Git's famous "ERROR: Permission to .git denied to user"

After Googling for few days, I found this is the only question similar to my situation.

However, I just solved the problem! So I am putting my answer here to help anyone else searching for this issue.

Here is what I did:

  1. Open "Keychain Access.app" (You can find it in Spotlight or LaunchPad)

  2. Select "All items" in Category

  3. Search "git"

  4. Delete every old & strange item

  5. Try to Push again and it just WORKED

Best way to use PHP to encrypt and decrypt passwords?

One thing you should be very aware of when dealing with encryption:

Trying to be clever and inventing your own thing usually will leave you with something insecure.

You'd probably be best off using one of the cryptography extensions that come with PHP.

How to read XML using XPath in Java

If you have a xml like below

<e:Envelope
    xmlns:d = "http://www.w3.org/2001/XMLSchema"
    xmlns:e = "http://schemas.xmlsoap.org/soap/envelope/"
    xmlns:wn0 = "http://systinet.com/xsd/SchemaTypes/"
    xmlns:i = "http://www.w3.org/2001/XMLSchema-instance">
    <e:Header>
        <Friends>
            <friend>
                <Name>Testabc</Name>
                <Age>12121</Age>
                <Phone>Testpqr</Phone>
            </friend>
        </Friends>
    </e:Header>
    <e:Body>
        <n0:ForAnsiHeaderOperResponse xmlns:n0 = "http://systinet.com/wsdl/com/magicsoftware/ibolt/localhost/ForAnsiHeader/ForAnsiHeaderImpl#ForAnsiHeaderOper?KExqYXZhL2xhbmcvU3RyaW5nOylMamF2YS9sYW5nL1N0cmluZzs=">
            <response i:type = "d:string">12--abc--pqr</response>
        </n0:ForAnsiHeaderOperResponse>
    </e:Body>
</e:Envelope>

and wanted to extract the below xml

<e:Header>
   <Friends>
      <friend>
         <Name>Testabc</Name>
         <Age>12121</Age>
         <Phone>Testpqr</Phone>
      </friend>
   </Friends>
</e:Header>

The below code helps to achieve the same

public static void main(String[] args) {

    File fXmlFile = new File("C://Users//abhijitb//Desktop//Test.xml");
    DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
    Document document;
    Node result = null;
    try {
        document = dbf.newDocumentBuilder().parse(fXmlFile);
        XPath xPath = XPathFactory.newInstance().newXPath();
        String xpathStr = "//Envelope//Header";
        result = (Node) xPath.evaluate(xpathStr, document, XPathConstants.NODE);
        System.out.println(nodeToString(result));
    } catch (SAXException | IOException | ParserConfigurationException | XPathExpressionException
            | TransformerException e) {
        e.printStackTrace();
    }
}

private static String nodeToString(Node node) throws TransformerException {
    StringWriter buf = new StringWriter();
    Transformer xform = TransformerFactory.newInstance().newTransformer();
    xform.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
    xform.transform(new DOMSource(node), new StreamResult(buf));
    return (buf.toString());
}

Now if you want only the xml like below

<Friends>
   <friend>
      <Name>Testabc</Name>
      <Age>12121</Age>
      <Phone>Testpqr</Phone>
   </friend>
</Friends>

You need to change the

String xpathStr = "//Envelope//Header"; to String xpathStr = "//Envelope//Header/*";

How can I get current date in Android?

This is the code i used:

             Date date = new Date();  // to get the date
             SimpleDateFormat df = new SimpleDateFormat("dd-MM-yyyy"); // getting date in this format
             String formattedDate = df.format(date.getTime());
             text.setText(formattedDate);

How to clear exisiting dropdownlist items when its content changes?

Just 2 simple steps to solve your issue

First of all check AppendDataBoundItems property and make it assign false

Secondly clear all the items using property .clear()

{
ddl1.Items.Clear();
ddl1.datasource = sql1;
ddl1.DataBind();
}

ASP.NET MVC: No parameterless constructor defined for this object

I had same problem but later found adding any new interface and corresponding class requires it to be registered under Initializable Module for dependency injection. In my case it was inside code as follows:

[InitializableModule]
[ModuleDependency(typeof(EPiServer.Web.InitializationModule))]
public class DependencyResolverInitialization : IConfigurableModule
{

    public void ConfigureContainer(ServiceConfigurationContext context)
    {
        context.Container.Configure(ConfigureContainer);
        var structureMapDependencyResolver = new StructureMapDependencyResolver(context.Container);
        DependencyResolver.SetResolver(structureMapDependencyResolver);
        GlobalConfiguration.Configuration.Services.Replace(typeof(IHttpControllerActivator), structureMapDependencyResolver);
    }

    private void ConfigureContainer(ConfigurationExpression container)
    {
        container.For<IAppSettingService>().Use<AppSettingService>();
        container.For<ISiteSettingService>().Use<SiteSettingService>();
        container.For<IBreadcrumbBuilder>().Use<BreadcrumbBuilder>();
        container.For<IFilterContentService>().Use<FilterContentService>().Singleton();
        container.For<IDependecyFactoryResolver>().Use<DependecyFactoryResolver>();
        container.For<IUserService>().Use<UserService>();
        container.For<IGalleryVmFactory>().Use<GalleryVmFactory>();
        container.For<ILanguageService>().Use<LanguageService>();
        container.For<ILanguageBranchRepository>().Use<LanguageBranchRepository>();
        container.For<ICacheService>().Use<CacheService>(); 
        container.For<ISearchService>().Use<SearchService>();
        container.For<IReflectionService>().Use<ReflectionService>();
        container.For<ILocalizationService>().Use<LocalizationService>();
        container.For<IBookingFormService>().Use<BookingFormService>();
        container.For<IGeoService>().Use<GeoService>();
        container.For<ILocationService>().Use<LocationService>();
        RegisterEnterpriseAPIClient(container);
    }

   public void Initialize(InitializationEngine context)
    {
    }

    public void Uninitialize(InitializationEngine context)
    {
    }

    public void Preload(string[] parameters)
    {
    }
}

}

iloc giving 'IndexError: single positional indexer is out-of-bounds'

This error is caused by:

Y = Dataset.iloc[:,18].values

Indexing is out of bounds here most probably because there are less than 19 columns in your Dataset, so column 18 does not exist. The following code you provided doesn't use Y at all, so you can just comment out this line for now.

What does <T> denote in C#

It is a generic type parameter, see Generics documentation.

T is not a reserved keyword. T, or any given name, means a type parameter. Check the following method (just as a simple example).

T GetDefault<T>()
{
    return default(T);
}

Note that the return type is T. With this method you can get the default value of any type by calling the method as:

GetDefault<int>(); // 0
GetDefault<string>(); // null
GetDefault<DateTime>(); // 01/01/0001 00:00:00
GetDefault<TimeSpan>(); // 00:00:00

.NET uses generics in collections, ... example:

List<int> integerList = new List<int>();

This way you will have a list that only accepts integers, because the class is instancited with the type T, in this case int, and the method that add elements is written as:

public class List<T> : ...
{
    public void Add(T item);
}

Some more information about generics.

You can limit the scope of the type T.

The following example only allows you to invoke the method with types that are classes:

void Foo<T>(T item) where T: class
{
}

The following example only allows you to invoke the method with types that are Circle or inherit from it.

void Foo<T>(T item) where T: Circle
{
}

And there is new() that says you can create an instance of T if it has a parameterless constructor. In the following example T will be treated as Circle, you get intellisense...

void Foo<T>(T item) where T: Circle, new()
{
    T newCircle = new T();
}

As T is a type parameter, you can get the object Type from it. With the Type you can use reflection...

void Foo<T>(T item) where T: class
{
    Type type = typeof(T);
}

As a more complex example, check the signature of ToDictionary or any other Linq method.

public static Dictionary<TKey, TSource> ToDictionary<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector);

There isn't a T, however there is TKey and TSource. It is recommended that you always name type parameters with the prefix T as shown above.

You could name TSomethingFoo if you want to.

How to set Android camera orientation properly?

I faced the issue when i was using ZBar for scanning in tabs. Camera orientation issue. Using below code i was able to resolve issue. This is not the whole code snippet, Please take only help from this.

 public void surfaceChanged(SurfaceHolder holder, int format, int width,
                               int height) {
     if (isPreviewRunning) {
            mCamera.stopPreview();
        }

 setCameraDisplayOrientation(mCamera);

        previewCamera();

    }



 public void previewCamera() {

        try {
            // Hard code camera surface rotation 90 degs to match Activity view
            // in portrait
            mCamera.setPreviewDisplay(mHolder);
            mCamera.setPreviewCallback(previewCallback);
            mCamera.startPreview();
            mCamera.autoFocus(autoFocusCallback);
            isPreviewRunning = true;
        } catch (Exception e) {
            Log.d("DBG", "Error starting camera preview: " + e.getMessage());
        }


    }


public void setCameraDisplayOrientation(android.hardware.Camera camera) {
        Camera.Parameters parameters = camera.getParameters();

        android.hardware.Camera.CameraInfo camInfo =
                new android.hardware.Camera.CameraInfo();
        android.hardware.Camera.getCameraInfo(getBackFacingCameraId(), camInfo);


        Display display = ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
        int rotation = display.getRotation();
        int degrees = 0;
        switch (rotation) {
            case Surface.ROTATION_0:
                degrees = 0;
                break;
            case Surface.ROTATION_90:
                degrees = 90;
                break;
            case Surface.ROTATION_180:
                degrees = 180;
                break;
            case Surface.ROTATION_270:
                degrees = 270;
                break;
        }

        int result;
        if (camInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
            result = (camInfo.orientation + degrees) % 360;
            result = (360 - result) % 360;  // compensate the mirror
        } else {  // back-facing
            result = (camInfo.orientation - degrees + 360) % 360;
        }
        camera.setDisplayOrientation(result);
    }




    private int getBackFacingCameraId() {
        int cameraId = -1;
        // Search for the front facing camera
        int numberOfCameras = Camera.getNumberOfCameras();
        for (int i = 0; i < numberOfCameras; i++) {
            Camera.CameraInfo info = new Camera.CameraInfo();
            Camera.getCameraInfo(i, info);
            if (info.facing == Camera.CameraInfo.CAMERA_FACING_BACK) {

                cameraId = i;
                break;
            }
        }
        return cameraId;
    }

Imitating a blink tag with CSS3 animations

There's actually no need for visibility or opacity - you can simply use color, which has the upside of keeping any "blinking" to the text only:

_x000D_
_x000D_
blink {_x000D_
    display: inline;_x000D_
    color: inherit;_x000D_
    animation: blink 1s steps(1) infinite;_x000D_
    -webkit-animation: blink 1s steps(1) infinite;_x000D_
}_x000D_
@keyframes blink { 50% { color: transparent; } }_x000D_
@-webkit-keyframes blink { 50% { color: transparent; } }
_x000D_
Here is some text, <blink>this text will blink</blink>, this will not.
_x000D_
_x000D_
_x000D_

Fiddle: http://jsfiddle.net/2r8JL/

Infinite Recursion with Jackson JSON and Hibernate JPA issue

There's now a Jackson module (for Jackson 2) specifically designed to handle Hibernate lazy initialization problems when serializing.

https://github.com/FasterXML/jackson-datatype-hibernate

Just add the dependency (note there are different dependencies for Hibernate 3 and Hibernate 4):

<dependency>
  <groupId>com.fasterxml.jackson.datatype</groupId>
  <artifactId>jackson-datatype-hibernate4</artifactId>
  <version>2.4.0</version>
</dependency>

and then register the module when intializing Jackson's ObjectMapper:

ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new Hibernate4Module());

Documentation currently isn't great. See the Hibernate4Module code for available options.

Clear input fields on form submit

You can access the form over the event:

e.target.reset();

What is the significance of url-pattern in web.xml and how to configure servlet?

url-pattern is used in web.xml to map your servlet to specific URL. Please see below xml code, similar code you may find in your web.xml configuration file.

<servlet>
    <servlet-name>AddPhotoServlet</servlet-name>  //servlet name
    <servlet-class>upload.AddPhotoServlet</servlet-class>  //servlet class
</servlet>
 <servlet-mapping>
    <servlet-name>AddPhotoServlet</servlet-name>   //servlet name
    <url-pattern>/AddPhotoServlet</url-pattern>  //how it should appear
</servlet-mapping>

If you change url-pattern of AddPhotoServlet from /AddPhotoServlet to /MyUrl. Then, AddPhotoServlet servlet can be accessible by using /MyUrl. Good for the security reason, where you want to hide your actual page URL.

Java Servlet url-pattern Specification:

  1. A string beginning with a '/' character and ending with a '/*' suffix is used for path mapping.
  2. A string beginning with a '*.' prefix is used as an extension mapping.
  3. A string containing only the '/' character indicates the "default" servlet of the application. In this case the servlet path is the request URI minus the context path and the path info is null.
  4. All other strings are used for exact matches only.

Reference : Java Servlet Specification

You may also read this Basics of Java Servlet

How to Export Private / Secret ASC Key to Decrypt GPG Files

Similar to @Wolfram J's answer, here is a method to encrypt your private key with a passphrase:

gpg --output - --armor --export $KEYID | \
    gpg --output private_key.asc --armor --symmetric --cipher-algo AES256

And a corresponding method to decrypt:

gpg private_key.asc

How to export a Vagrant virtual machine to transfer it

As stated in

How can I change where Vagrant looks for its virtual hard drive?

the virtual-machine state is stored in a predefined VirtualBox folder. Copying the corresponding machine (folder) besides your vagrant-project to your other host should preserve your virtual machine state.

Convert string to List<string> in one line?

The List<T> has a constructor that accepts an IEnumerable<T>:

List<string> listOfNames = new List<string>(names.Split(','));

Can I check if Bootstrap Modal Shown / Hidden?

I try like this with function then calling if needed a this function. Has been worked for me.

function modal_fix() {
var a = $(".modal"),
    b = $("body");
a.on("shown.bs.modal", function () {
    b.hasClass("modal-open") || b.addClass("modal-open");
});
}

Checking if an object is null in C#

As of C# 9 you can do

if (obj is null) { ... }

For not null use

if (obj is not null) { ... }

If you need to override this behaviour use == and != accordingly.

How can I find the version of php that is running on a distinct domain name?

I use redbot, a great tool to see php version, but also many other useful infos like headers, encoding, keepalive and many more, try it on

http://redbot.org

I loveit !

I also upvote Neil answer : curl -I http://websitename.com

Change table header color using bootstrap

there's a bootstrap function to change the color of table header called thead-dark for dark background of table header and thead-light for light background of table header. Your code will look like this after using this function.

<table class="table">
    <tr class="thead-danger">
        <!-- here I used dark table headre -->
        <th>
            @Html.DisplayNameFor(model => model.name)
        </th>
        <th>
            @Html.DisplayNameFor(model => model.checkBox1)
        </th>
        <th></th>
    </tr>

Use css gradient over background image

Ok, I solved it by adding the url for the background image at the end of the line.

Here's my working code:

_x000D_
_x000D_
.css {_x000D_
  background: -moz-linear-gradient(top, rgba(0, 0, 0, 0) 0%, rgba(0, 0, 0, 0) 59%, rgba(0, 0, 0, 0.65) 100%), url('https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-icon.png?v=c78bd457575a') no-repeat;_x000D_
  background: -webkit-gradient(linear, left top, left bottom, color-stop(0%, rgba(0, 0, 0, 0)), color-stop(59%, rgba(0, 0, 0, 0)), color-stop(100%, rgba(0, 0, 0, 0.65))), url('https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-icon.png?v=c78bd457575a') no-repeat;_x000D_
  background: -webkit-linear-gradient(top, rgba(0, 0, 0, 0) 0%, rgba(0, 0, 0, 0) 59%, rgba(0, 0, 0, 0.65) 100%), url('https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-icon.png?v=c78bd457575a') no-repeat;_x000D_
  background: -o-linear-gradient(top, rgba(0, 0, 0, 0) 0%, rgba(0, 0, 0, 0) 59%, rgba(0, 0, 0, 0.65) 100%), url('https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-icon.png?v=c78bd457575a') no-repeat;_x000D_
  background: -ms-linear-gradient(top, rgba(0, 0, 0, 0) 0%, rgba(0, 0, 0, 0) 59%, rgba(0, 0, 0, 0.65) 100%), url('https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-icon.png?v=c78bd457575a') no-repeat;_x000D_
  background: linear-gradient(to bottom, rgba(0, 0, 0, 0) 0%, rgba(0, 0, 0, 0) 59%, rgba(0, 0, 0, 0.65) 100%), url('https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-icon.png?v=c78bd457575a') no-repeat;_x000D_
  height: 200px;_x000D_
_x000D_
}
_x000D_
<div class="css"></div>
_x000D_
_x000D_
_x000D_

Change event on select with knockout binding, how can I know if it is a real change?

Actually you want to find whether the event is triggered by user or program , and its obvious that event will trigger while initialization.

The knockout approach of adding subscription won't help in all cases, why because in most of the model will be implemented like this

  1. init the model with undefined data , just structure (actual KO initilization)
  2. update the model with initial data (logical init like load JSON , get data etc)
  3. User interaction and updates

The actual step that we want to capture is changes in 3, but in second step subscription will get call , So a better way is to add to event change like

 <select data-bind="value: level, event:{ change: $parent.permissionChanged}">

and detected the event in permissionChanged function

this.permissionChanged = function (obj, event) {

  if (event.originalEvent) { //user changed

  } else { // program changed

  }

}

Your project contains error(s), please fix it before running it

This is happened to me. After format of my system,
When i import project it shows same error

remove first debug.keystore file then goto -

Project -> Project properties -> select library -> remove -> add again libraries.

It's working for me......

How to limit text width

<style>
     p{
         width:     70%
         word-wrap: break-word;
     }
</style>

This wasn't working in my case. It worked fine after adding following style.

<style>
     p{
        width:     70%
        word-break: break-all;
     }
</style>

compression and decompression of string data in java

You can't convert binary data to String. As a solution you can encode binary data and then convert to String. For example, look at this How do you convert binary data to Strings and back in Java?

How can I INSERT data into two tables simultaneously in SQL Server?

Try this:

insert into [table] ([data])
output inserted.id, inserted.data into table2
select [data] from [external_table]

UPDATE: Re:

Denis - this seems very close to what I want to do, but perhaps you could fix the following SQL statement for me? Basically the [data] in [table1] and the [data] in [table2] represent two different/distinct columns from [external_table]. The statement you posted above only works when you want the [data] columns to be the same.

INSERT INTO [table1] ([data]) 
OUTPUT [inserted].[id], [external_table].[col2] 
INTO [table2] SELECT [col1] 
FROM [external_table] 

It's impossible to output external columns in an insert statement, so I think you could do something like this

merge into [table1] as t
using [external_table] as s
on 1=0 --modify this predicate as necessary
when not matched then insert (data)
values (s.[col1])
output inserted.id, s.[col2] into [table2]
;

Adding a dictionary to another

Create an Extension Method most likely you will want to use this more than once and this prevents duplicate code.

Implementation:

 public static void AddRange<T, S>(this Dictionary<T, S> source, Dictionary<T, S> collection)
 {
        if (collection == null)
        {
            throw new ArgumentNullException("Collection is null");
        }

        foreach (var item in collection)
        {
            if(!source.ContainsKey(item.Key)){ 
               source.Add(item.Key, item.Value);
            }
            else
            {
               // handle duplicate key issue here
            }  
        } 
 }

Usage:

Dictionary<string,string> animals = new Dictionary<string,string>();
Dictionary<string,string> newanimals = new Dictionary<string,string>();

animals.AddRange(newanimals);

Display all post meta keys and meta values of the same post ID in wordpress

Default Usage

Get the meta for all keys:

<?php $meta = get_post_meta($post_id); ?>

Get the meta for a single key:

<?php $key_1_values = get_post_meta( 76, 'key_1' ); ?>

for example:

$myvals = get_post_meta($post_id);

foreach($myvals as $key=>$val)
{
    echo $key . ' : ' . $val[0] . '<br/>';
}

Note: some unwanted meta keys starting with "underscore(_)" will also come, so you will need to filter them out.

For reference: See Codex

How to navigate to to different directories in the terminal (mac)?

To check that the file you're trying to open actually exists, you can change directories in terminal using cd. To change to ~/Desktop/sass/css: cd ~/Desktop/sass/css. To see what files are in the directory: ls.

If you want information about either of those commands, use the man page: man cd or man ls, for example.

Google for "basic unix command line commands" or similar; that will give you numerous examples of moving around, viewing files, etc in the command line.

On Mac OS X, you can also use open to open a finder window: open . will open the current directory in finder. (open ~/Desktop/sass/css will open the ~/Desktop/sass/css).

Why do people use Heroku when AWS is present? What distinguishes Heroku from AWS?

Sometimes, I wonder why people compare AWS to Heroku. AWS is an IAAS( infrastructure as a service) it clearly speaks how robust and calculative the system is. Heroku, on the other hand, is just a SAAS, it is basically just one fraction of AWS services. So why struggle with setting up AWS when you can ship your first product to the prime using Heroku.

Heroku is free, simple and easy to deploy almost all types of stacks to the web. Heroku is specifically built to bypass all the hassles of shipping your application to a live server in less than no time.

Nevertheless, you may want to deploy your application using any of the tutorials from both parties and compare

AWS DOCS and Heroku Docs

What is the best way to implement nested dictionaries?

class AutoVivification(dict):
    """Implementation of perl's autovivification feature."""
    def __getitem__(self, item):
        try:
            return dict.__getitem__(self, item)
        except KeyError:
            value = self[item] = type(self)()
            return value

Testing:

a = AutoVivification()

a[1][2][3] = 4
a[1][3][3] = 5
a[1][2]['test'] = 6

print a

Output:

{1: {2: {'test': 6, 3: 4}, 3: {3: 5}}}

How to unpack pkl file?

Generally

Your pkl file is, in fact, a serialized pickle file, which means it has been dumped using Python's pickle module.

To un-pickle the data you can:

import pickle


with open('serialized.pkl', 'rb') as f:
    data = pickle.load(f)

For the MNIST data set

Note gzip is only needed if the file is compressed:

import gzip
import pickle


with gzip.open('mnist.pkl.gz', 'rb') as f:
    train_set, valid_set, test_set = pickle.load(f)

Where each set can be further divided (i.e. for the training set):

train_x, train_y = train_set

Those would be the inputs (digits) and outputs (labels) of your sets.

If you want to display the digits:

import matplotlib.cm as cm
import matplotlib.pyplot as plt


plt.imshow(train_x[0].reshape((28, 28)), cmap=cm.Greys_r)
plt.show()

mnist_digit

The other alternative would be to look at the original data:

http://yann.lecun.com/exdb/mnist/

But that will be harder, as you'll need to create a program to read the binary data in those files. So I recommend you to use Python, and load the data with pickle. As you've seen, it's very easy. ;-)

System.Net.WebException: The operation has timed out

proxy issue can cause this. IIS webconfig put this in

<defaultProxy useDefaultCredentials="true" enabled="true">
          <proxy usesystemdefault="True" />
        </defaultProxy>

How to place div side by side

There are many ways to do what you're asking for:

  1. Using CSS float property:

_x000D_
_x000D_
 <div style="width: 100%; overflow: hidden;">
     <div style="width: 600px; float: left;"> Left </div>
     <div style="margin-left: 620px;"> Right </div>
</div>
_x000D_
_x000D_
_x000D_

  1. Using CSS display property - which can be used to make divs act like a table:

_x000D_
_x000D_
<div style="width: 100%; display: table;">
    <div style="display: table-row">
        <div style="width: 600px; display: table-cell;"> Left </div>
        <div style="display: table-cell;"> Right </div>
    </div>
</div>
_x000D_
_x000D_
_x000D_

There are more methods, but those two are the most popular.

Visualizing branch topology in Git

A nice web based tool is ungit. It runs on any platform that node.js & git supports. There is a video of how it works for those that find that sort of things easier than reading...

enter image description here

What is the difference between Views and Materialized Views in Oracle?

Materialised view - a table on a disk that contains the result set of a query

Non-materiased view - a query that pulls data from the underlying table

Where to find htdocs in XAMPP Mac

Open xampp application, then do the following:

  1. go to: volumes,

  2. click the [mount] button, and

  3. finally click explore.

Under what circumstances can I call findViewById with an Options Menu / Action Bar item?

I am trying to obtain a handle on one of the views in the Action Bar

I will assume that you mean something established via android:actionLayout in your <item> element of your <menu> resource.

I have tried calling findViewById(R.id.menu_item)

To retrieve the View associated with your android:actionLayout, call findItem() on the Menu to retrieve the MenuItem, then call getActionView() on the MenuItem. This can be done any time after you have inflated the menu resource.

how to add super privileges to mysql database?

You can add super privilege using phpmyadmin:

Go to PHPMYADMIN > privileges > Edit User > Under Administrator tab Click SUPER. > Go

If you want to do it through Console, do like this:

 mysql> GRANT SUPER ON *.* TO user@'localhost' IDENTIFIED BY 'password';

After executing above code, end it with:

mysql> FLUSH PRIVILEGES;

You should do in on *.* because SUPER is not the privilege that applies just to one database, it's global.

Mount current directory as a volume in Docker on Windows 10

This works for me in PowerShell:

docker run --rm -v ${PWD}:/data alpine ls /data

Console app arguments, how arguments are passed to Main method

All answers are awesome and explained everything very well

but I just want to point out different way for passing args to main method

in visual studio

  1. right click on Project then choose Properties
  2. go to Debug tab then on the Start Options section provide the app with your args

like this image

Properties window

and happy knowing secrets

compare differences between two tables in mysql

Problem below, is to compare table before and after i do big update!.

If you use Linux, you can use commands as follow:

In terminal,

mysqldump -hlocalhost -uroot -p schema_name_here table_name_here > /home/ubuntu/database_dumps/dump_table_before_running_update.sql

mysqldump -hlocalhost -uroot -p schema_name_here table_name_here > /home/ubuntu/database_dumps/dump_table_after_running_update.sql

diff -uP /home/ubuntu/database_dumps/dump_some_table_after_running_update.sql /home/ubuntu/database_dumps/dump_table_before_running_update.sql > /home/ubuntu/database_dumps/diff.txt

You will need online tools for

  • Formatting SQL exported from the dumps,

e.g http://www.dpriver.com/pp/sqlformat.htm [Not the best I've seen]

  • We have diff.txt, you have to take manually the + - showing inside, which is 1 line of insert statements, that has the values.

  • Do diff online for the 2 lines - & + in diff.txt, past them in online diff tool

e.g https://www.diffchecker.com [you can save and share it, and has no limit on file size!]

Note: be extra careful if its sensitive/production data!

diff preview

How diff.txt will look like

Define the selected option with the old input in Laravel / Blade

      <select class="form-control" name="kategori_id">
        <option value="">-- PILIH --</option>
        @foreach($kategori as $id => $nama)
            @if(old('kategori_id', $produk->kategori_id) == $id )
            <option value="{{ $id }}" selected>{{ $nama }}</option>
            @else
            <option value="{{ $id }}">{{ $nama }}</option>
            @endif
        @endforeach
        </select>

How to store an array into mysql?

You can use the php serialize function to store array in MySQL.

<?php

$array = array("Name"=>"Shubham","Age"=>"17","website"=>"http://mycodingtricks.com");

$string_array = serialize($array);

echo $string_array;

?>

It’s output will be :

a:3{s:4:"Name";s:7:"Shubham";s:3:"Age";s:2:"17";s:7:"website";s:25:"http://mycodingtricks.com";}

And then you can use the php unserialize function to decode the data.

I think you should visit this page on storing array in mysql.

Java ArrayList of Arrays?

BTW. you should prefer coding against an Interface.

private ArrayList<String[]> action = new ArrayList<String[]>();

Should be

private List<String[]> action = new ArrayList<String[]>();

How do I make an editable DIV look like a text field?

You can place a TEXTAREA of similar size under your DIV, so the standard control's frame would be visible around div.

It's probably good to set it to be disabled, to prevent accidental focus stealing.

Can I define a class name on paragraph using Markdown?

Raw HTML is actually perfectly valid in markdown. For instance:

Normal *markdown* paragraph.

<p class="myclass">This paragraph has a class "myclass"</p>

Just make sure the HTML is not inside a code block.

Getting value from appsettings.json in .net core

.NET core 3.X

no need to create new model and to set in Startup.cs.

Controller Add new package - using Microsoft.Extensions.Configuration;

public class HomeController : Controller
{
    private readonly IConfiguration _mySettings;

    public HomeController (IConfiguration mySettings)
    {
         _mySettings= mySettings;
    }
 
    //ex: you can get value on below function 
    public IEnumerable<string> Get()
    {
        var result = _config.GetValue<string>("AppSettings:Version"); // "One"
        return new string[] { result.ToString() };
    }
}

Parameterize an SQL IN clause

In SQL Server 2016+ another possibility is to use the OPENJSON function.

This approach is blogged about in OPENJSON - one of best ways to select rows by list of ids.

A full worked example below

CREATE TABLE dbo.Tags
  (
     Name  VARCHAR(50),
     Count INT
  )

INSERT INTO dbo.Tags
VALUES      ('VB',982), ('ruby',1306), ('rails',1478), ('scruffy',1), ('C#',1784)

GO

CREATE PROC dbo.SomeProc
@Tags VARCHAR(MAX)
AS
SELECT T.*
FROM   dbo.Tags T
WHERE  T.Name IN (SELECT J.Value COLLATE Latin1_General_CI_AS
                  FROM   OPENJSON(CONCAT('[', @Tags, ']')) J)
ORDER  BY T.Count DESC

GO

EXEC dbo.SomeProc @Tags = '"ruby","rails","scruffy","rubyonrails"'

DROP TABLE dbo.Tags 

how to create a Java Date object of midnight today and midnight tomorrow?

Pretty much as the answers before, but nobody mentioned AM_PM parameter:

    Calendar cal = Calendar.getInstance();
    cal.set(Calendar.HOUR, 0);
    cal.set(Calendar.MINUTE, 0);
    cal.set(Calendar.SECOND, 0);
    cal.set(Calendar.MILLISECOND, 0);
    cal.set(Calendar.AM_PM, Calendar.AM);

jquery: get id from class selector

Nothing from this examples , works for me

for (var i = 0; i < res.results.length; i++) {
        $('#list_tags').append('<li class="dd-item" id="'+ res.results[i].id + '"><div class="dd-handle root-group">' + res.results[i].name + '</div></li>');
}

    $('.dd-item').click(function () {
    console.log($(this).attr('id'));
    });

installing cPickle with python 3.5

cPickle comes with the standard library… in python 2.x. You are on python 3.x, so if you want cPickle, you can do this:

>>> import _pickle as cPickle

However, in 3.x, it's easier just to use pickle.

No need to install anything. If something requires cPickle in python 3.x, then that's probably a bug.

Multi-key dictionary in c#?

Here's a fleshed out example of a pair class which can be used as the key to a Dictionary.

public class Pair<T1, T2>
{
    public T1 Left { get; private set; }
    public T2 Right { get; private set; }

    public Pair(T1 t1, T2 t2)
    {
        Left = t1;
        Right = t2;
    }

    public override bool Equals(object obj)
    {
        if (ReferenceEquals(null, obj)) return false;
        if (ReferenceEquals(this, obj)) return true;
        if (obj.GetType() != typeof(Pair<T1, T2>)) return false;
        return Equals((Pair<T1, T2>)obj);
    }

    public bool Equals(Pair<T1, T2> obj)
    {
        if (ReferenceEquals(null, obj)) return false;
        if (ReferenceEquals(this, obj)) return true;
        return Equals(obj.Left, Left) && Equals(obj.Right, Right);
    }

    public override int GetHashCode()
    {
        unchecked
        {
            return (Left.GetHashCode() * 397) ^ Right.GetHashCode();
        }
    }
}

Page unload event in asp.net

There is an event Page.Unload. At that moment page is already rendered in HTML and HTML can't be modified. Still, all page objects are available.

IF/ELSE Stored Procedure

Just a tip for this, you don't need the BEGIN and END if it only contains a single statement.

ie:

IF(@Trans_type = 'subscr_signup')    
 set @tmpType = 'premium' 
ELSE iF(@Trans_type = 'subscr_cancel')  
     set    @tmpType = 'basic'

Multiple "style" attributes in a "span" tag: what's supposed to happen?

Separate your rules with a semi colon in a single declaration:

<span style="color:blue;font-style:italic">Test</span>

How to set the maxAllowedContentLength to 500MB while running on IIS7?

According to MSDN maxAllowedContentLength has type uint, its maximum value is 4,294,967,295 bytes = 3,99 gb

So it should work fine.

See also Request Limits article. Does IIS return one of these errors when the appropriate section is not configured at all?

See also: Maximum request length exceeded

Can HTTP POST be limitless?

EDIT (2019) This answer is now pretty redundant but there is another answer with more relevant information.

It rather depends on the web server and web browser:

Internet explorer All versions 2GB-1
Mozilla Firefox All versions 2GB-1
IIS 1-5 2GB-1
IIS 6 4GB-1

Although IIS only support 200KB by default, the metabase needs amending to increase this.

http://www.motobit.com/help/scptutl/pa98.htm

The POST method itself does not have any limit on the size of data.

Labeling file upload button

Take a step back! Firstly, you're assuming the user is using a foreign locale on their device, which is not a sound assumption for justifying taking over the button text of the file picker, and making it say what you want it to.

It is reasonable that you want to control every item of language visible on your page. The content of the File Upload control is not part of the HTML though. There is more content behind this control, for example, in WebKit, it also says "No file chosen" next to the button.

There are very hacky workarounds that attempt this (e.g. like those mentioned in @ChristopheD's answer), but none of them truly succeed:

  • To a screen reader, the file control will still say "Browse..." or "Choose File", and a custom file upload will not be announced as a file upload control, but just a button or a text input.
  • Many of them fail to display the chosen file, or to show that the user has no longer chosen a file
  • Many of them look nothing like the native control, so might look strange on non-standard devices.
  • Keyboard support is typically poor.
  • An author-created UI component can never be as fully functional as its native equivalent (and the closer you get it to behave to suppose IE10 on Windows 7, the more it will deviate from other Browser and Operating System combinations).
  • Modern browsers support drag & drop into the native file upload control.
  • Some techniques may trigger heuristics in security software as a potential ‘click-jacking’ attempt to trick the user into uploading file.

Deviating from the native controls is always a risky thing, there is a whole host of different devices your users could be using, and whatever workaround you choose, you will not have tested it in every one of those devices.

However, there is an even bigger reason why all attempts fail from a User Experience perspective: there is even more non-localized content behind this control, the file selection dialog itself. Once the user is subject to traversing their file system or what not to select a file to upload, they will be subjected to the host Operating System locale.

Are you sure you're doing your user any justice by deviating from the native control, just to localize the text, when as soon as they click it, they're just going to get the Operating System locale anyway?

The best you can do for your users is to ensure you have adequate localised guidance surrounding your file input control. (e.g. Form field label, hint text, tooltip text).

Sorry. :-(

--

This answer is for those looking for any justification not to localise the file upload control.

Create an array of integers property in Objective-C

Like lucius said, it's not possible to have a C array property. Using an NSArray is the way to go. An array only stores objects, so you'd have to use NSNumbers to store your ints. With the new literal syntax, initialising it is very easy and straight-forward:

NSArray *doubleDigits = @[ @1, @2, @3, @4, @5, @6, @7, @8, @9, @10 ];

Or:

NSMutableArray *doubleDigits = [NSMutableArray array];

for (int n = 1; n <= 10; n++)
    [doubleDigits addObject:@(n)];

For more information: NSArray Class Reference, NSNumber Class Reference, Literal Syntax

Hidden Features of Xcode

Xcode code formatting... is one of the thing you need when you want to make your code readable and look good.

You can do the code formatting by yourself or save some time using scripts.

One good way is.. use Uncrustify. It is explained in Code Formatting in Xcode.

Environment variable substitution in sed

I had similar problem, I had a list and I have to build a SQL script based on template (that contained @INPUT@ as element to replace):

for i in LIST 
do
    awk "sub(/\@INPUT\@/,\"${i}\");" template.sql >> output
done

What is the Ruby <=> (spaceship) operator?

What is <=> ( The 'Spaceship' Operator )

According to the RFC that introduced the operator, $a <=> $b

 -  0 if $a == $b
 - -1 if $a < $b
 -  1 if $a > $b

 - Return 0 if values on either side are equal
 - Return 1 if value on the left is greater
 - Return -1 if the value on the right is greater

Example:

//Comparing Integers

echo 1 <=> 1; //ouputs 0
echo 3 <=> 4; //outputs -1
echo 4 <=> 3; //outputs 1

//String Comparison

echo "x" <=> "x"; // 0
echo "x" <=> "y"; //-1
echo "y" <=> "x"; //1

MORE:

// Integers
echo 1 <=> 1; // 0
echo 1 <=> 2; // -1
echo 2 <=> 1; // 1

// Floats
echo 1.5 <=> 1.5; // 0
echo 1.5 <=> 2.5; // -1
echo 2.5 <=> 1.5; // 1

// Strings
echo "a" <=> "a"; // 0
echo "a" <=> "b"; // -1
echo "b" <=> "a"; // 1

echo "a" <=> "aa"; // -1
echo "zz" <=> "aa"; // 1

// Arrays
echo [] <=> []; // 0
echo [1, 2, 3] <=> [1, 2, 3]; // 0
echo [1, 2, 3] <=> []; // 1
echo [1, 2, 3] <=> [1, 2, 1]; // 1
echo [1, 2, 3] <=> [1, 2, 4]; // -1

// Objects
$a = (object) ["a" => "b"]; 
$b = (object) ["a" => "b"]; 
echo $a <=> $b; // 0

'No database provider has been configured for this DbContext' on SignInManager.PasswordSignInAsync

I could resolve it by overriding Configuration in MyContext through adding connection string to the DbContextOptionsBuilder:

protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        if (!optionsBuilder.IsConfigured)
        {
            IConfigurationRoot configuration = new ConfigurationBuilder()
               .SetBasePath(Directory.GetCurrentDirectory())
               .AddJsonFile("appsettings.json")
               .Build();
            var connectionString = configuration.GetConnectionString("DbCoreConnectionString");
            optionsBuilder.UseSqlServer(connectionString);
        }
    }

Synchronous XMLHttpRequest warning and <script>

Browsers now warn for the use of synchronous XHR. MDN says this was implemented recently:

Starting with Gecko 30.0 (Firefox 30.0 / Thunderbird 30.0 / SeaMonkey 2.27)

https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/Synchronous_and_Asynchronous_Requests#Synchronous_request

Here's how the change got implemented in Firefox and Chromium:

As for Chrome people report this started happening somewhere around version 39. I'm not sure how to link a revision/changeset to a particular version of Chrome.

Yes, it happens when jQuery appends markup to the page including script tags that load external js files. You can reproduce it with something like this:

$('body').append('<script src="foo.js"></script>');

I guess jQuery will fix this in some future version. Until then we can either ignore it or use A. Wolff's suggestion above.

Getting next element while cycling through a list

I've used enumeration to handle this problem.

storage = ''
for num, value in enumerate(result, start=0):
    content = value
    if 'A' == content:
        storage = result[num + 1]

I've used num as Index here, when it finds the correct value it adds up one to the current index of actual list. Which allows me to maneuver to the next index.

I hope this helps your purpose.

Writing Python lists to columns in csv

change them to rows

rows = zip(list1,list2,list3,list4,list5)

then just

import csv

with open(newfilePath, "w") as f:
    writer = csv.writer(f)
    for row in rows:
        writer.writerow(row)

SQL SERVER, SELECT statement with auto generate row id

Here is a simple method which ranks the rows after however they are ordered, i.e. inserted in your table. In your SELECT statement simply add the field

ROW_NUMBER() OVER (ORDER BY CAST(GETDATE() AS TIMESTAMP)) AS RowNumber.

How do a LDAP search/authenticate against this LDAP in Java

You can also use the following code :

package com.agileinfotech.bsviewer.ldap;

import java.util.Hashtable;
import java.util.ResourceBundle;

import javax.naming.Context;
import javax.naming.NamingException;
import javax.naming.directory.DirContext;
import javax.naming.directory.InitialDirContext;

public class LDAPLoginAuthentication {
    public LDAPLoginAuthentication() {
        // TODO Auto-generated constructor
    }

    ResourceBundle resBundle = ResourceBundle.getBundle("settings");

    @SuppressWarnings("unchecked")
    public String authenticateUser(String username, String password) {
        String strUrl = "success";
        Hashtable env = new Hashtable(11);
        boolean b = false;
        String Securityprinciple = "cn=" + username + "," + resBundle.getString("UserSearch");
        env.put(Context.INITIAL_CONTEXT_FACTORY, resBundle.getString("InitialContextFactory"));
        env.put(Context.PROVIDER_URL, resBundle.getString("Provider_url"));
        env.put(Context.SECURITY_AUTHENTICATION, "simple");
        env.put(Context.SECURITY_PRINCIPAL, Securityprinciple);
        env.put(Context.SECURITY_CREDENTIALS, password);

        try {
            // Create initial context
            DirContext ctx = new InitialDirContext(env);
            // Close the context when we're done
            b = true;
            ctx.close();

        } catch (NamingException e) {
            b = false;
        } finally {
            if (b) {
                strUrl = "success";
            } else {
                strUrl = "failer";
            }
        }
        return strUrl;
    }
}

Export SQL query data to Excel

For anyone coming here looking for how to do this in C#, I have tried the following method and had success in dotnet core 2.0.3 and entity framework core 2.0.3

First create your model class.

public class User
{  
    public string Name { get; set; }  
    public int Address { get; set; }  
    public int ZIP { get; set; }  
    public string Gender { get; set; }  
} 

Then install EPPlus Nuget package. (I used version 4.0.5, probably will work for other versions as well.)

Install-Package EPPlus -Version 4.0.5

The create ExcelExportHelper class, which will contain the logic to convert dataset to Excel rows. This class do not have dependencies with your model class or dataset.

public class ExcelExportHelper
    {
        public static string ExcelContentType
        {
            get
            { return "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"; }
        }

        public static DataTable ListToDataTable<T>(List<T> data)
        {
            PropertyDescriptorCollection properties = TypeDescriptor.GetProperties(typeof(T));
            DataTable dataTable = new DataTable();

            for (int i = 0; i < properties.Count; i++)
            {
                PropertyDescriptor property = properties[i];
                dataTable.Columns.Add(property.Name, Nullable.GetUnderlyingType(property.PropertyType) ?? property.PropertyType);
            }

            object[] values = new object[properties.Count];
            foreach (T item in data)
            {
                for (int i = 0; i < values.Length; i++)
                {
                    values[i] = properties[i].GetValue(item);
                }

                dataTable.Rows.Add(values);
            }
            return dataTable;
        }

        public static byte[] ExportExcel(DataTable dataTable, string heading = "", bool showSrNo = false, params string[] columnsToTake)
        {

            byte[] result = null;
            using (ExcelPackage package = new ExcelPackage())
            {
                ExcelWorksheet workSheet = package.Workbook.Worksheets.Add(String.Format("{0} Data", heading));
                int startRowFrom = String.IsNullOrEmpty(heading) ? 1 : 3;

                if (showSrNo)
                {
                    DataColumn dataColumn = dataTable.Columns.Add("#", typeof(int));
                    dataColumn.SetOrdinal(0);
                    int index = 1;
                    foreach (DataRow item in dataTable.Rows)
                    {
                        item[0] = index;
                        index++;
                    }
                }


                // add the content into the Excel file  
                workSheet.Cells["A" + startRowFrom].LoadFromDataTable(dataTable, true);

                // autofit width of cells with small content  
                int columnIndex = 1;
                foreach (DataColumn column in dataTable.Columns)
                {
                    int maxLength;
                    ExcelRange columnCells = workSheet.Cells[workSheet.Dimension.Start.Row, columnIndex, workSheet.Dimension.End.Row, columnIndex];
                    try
                    {
                        maxLength = columnCells.Max(cell => cell.Value.ToString().Count());
                    }
                    catch (Exception) //nishanc
                    {
                        maxLength = columnCells.Max(cell => (cell.Value +"").ToString().Length);
                    }

                    //workSheet.Column(columnIndex).AutoFit();
                    if (maxLength < 150)
                    {
                        //workSheet.Column(columnIndex).AutoFit();
                    }


                    columnIndex++;
                }

                // format header - bold, yellow on black  
                using (ExcelRange r = workSheet.Cells[startRowFrom, 1, startRowFrom, dataTable.Columns.Count])
                {
                    r.Style.Font.Color.SetColor(System.Drawing.Color.White);
                    r.Style.Font.Bold = true;
                    r.Style.Fill.PatternType = OfficeOpenXml.Style.ExcelFillStyle.Solid;
                    r.Style.Fill.BackgroundColor.SetColor(Color.Brown);
                }

                // format cells - add borders  
                using (ExcelRange r = workSheet.Cells[startRowFrom + 1, 1, startRowFrom + dataTable.Rows.Count, dataTable.Columns.Count])
                {
                    r.Style.Border.Top.Style = ExcelBorderStyle.Thin;
                    r.Style.Border.Bottom.Style = ExcelBorderStyle.Thin;
                    r.Style.Border.Left.Style = ExcelBorderStyle.Thin;
                    r.Style.Border.Right.Style = ExcelBorderStyle.Thin;

                    r.Style.Border.Top.Color.SetColor(System.Drawing.Color.Black);
                    r.Style.Border.Bottom.Color.SetColor(System.Drawing.Color.Black);
                    r.Style.Border.Left.Color.SetColor(System.Drawing.Color.Black);
                    r.Style.Border.Right.Color.SetColor(System.Drawing.Color.Black);
                }

                // removed ignored columns  
                for (int i = dataTable.Columns.Count - 1; i >= 0; i--)
                {
                    if (i == 0 && showSrNo)
                    {
                        continue;
                    }
                    if (!columnsToTake.Contains(dataTable.Columns[i].ColumnName))
                    {
                        workSheet.DeleteColumn(i + 1);
                    }
                }

                if (!String.IsNullOrEmpty(heading))
                {
                    workSheet.Cells["A1"].Value = heading;
                   // workSheet.Cells["A1"].Style.Font.Size = 20;

                    workSheet.InsertColumn(1, 1);
                    workSheet.InsertRow(1, 1);
                    workSheet.Column(1).Width = 10;
                }

                result = package.GetAsByteArray();
            }

            return result;
        }

        public static byte[] ExportExcel<T>(List<T> data, string Heading = "", bool showSlno = false, params string[] ColumnsToTake)
        {
            return ExportExcel(ListToDataTable<T>(data), Heading, showSlno, ColumnsToTake);
        }
    }

Now add this method where you want to generate the excel file, probably for a method in the controller. You can pass parameters for your stored procedure as well. Note that the return type of the method is FileContentResult. Whatever query you execute, important thing is you must have the results in a List.

[HttpPost]
public async Task<FileContentResult> Create([Bind("Id,StartDate,EndDate")] GetReport getReport)
{
    DateTime startDate = getReport.StartDate;
    DateTime endDate = getReport.EndDate;

    // call the stored procedure and store dataset in a List.
    List<User> users = _context.Reports.FromSql("exec dbo.SP_GetEmpReport @start={0}, @end={1}", startDate, endDate).ToList();
    //set custome column names
    string[] columns = { "Name", "Address", "ZIP", "Gender"};
    byte[] filecontent = ExcelExportHelper.ExportExcel(users, "Users", true, columns);
    // set file name.
    return File(filecontent, ExcelExportHelper.ExcelContentType, "Report.xlsx"); 
}

More details can be found here