Programs & Examples On #Affiliates

How to change Oracle default data pump directory to import dumpfile?

I want change default directory dumpfile.

You could create a new directory and give it required privileges, for example:

SQL> CREATE DIRECTORY dmpdir AS '/opt/oracle';
Directory created.

SQL> GRANT read, write ON DIRECTORY dmpdir TO scott;
Grant succeeded.

To use the newly created directory, you could just add it as a parameter:

DIRECTORY=dmpdir

Oracle introduced a default directory from 10g R2, called DATA_PUMP_DIR, that can be used. To check the location, you could look into dba_directories:

SQL> select DIRECTORY_NAME, DIRECTORY_PATH from dba_directories where DIRECTORY_NAME = 'DATA_PUMP_DIR';

DIRECTORY_NAME       DIRECTORY_PATH
-------------------- --------------------------------------------------
DATA_PUMP_DIR        C:\app\Lalit/admin/orcl/dpdump/

SQL>

Drop-down menu that opens up/upward with pure css

If we are use chosen dropdown list, then we can use below css(No JS/JQuery require)

<select chosen="{width: '100%'}" ng- 
   model="modelName" class="form-control input- 
   sm"
   ng- 
   options="persons.persons as 
   persons.persons for persons in 
   jsonData"
   ng- 
   change="anyFunction(anyParam)" 
   required>
   <option value=""> </option>
</select>
<style>   
.chosen-container .chosen-drop {
    border-bottom: 0;
    border-top: 1px solid #aaa;
    top: auto;
    bottom: 40px;
}

.chosen-container.chosen-with-drop .chosen-single {
    border-top-left-radius: 0px;
    border-top-right-radius: 0px;

    border-bottom-left-radius: 5px;
    border-bottom-right-radius: 5px;

    background-image: none;
}

.chosen-container.chosen-with-drop .chosen-drop {
    border-bottom-left-radius: 0px;
    border-bottom-right-radius: 0px;

    border-top-left-radius: 5px;
    border-top-right-radius: 5px;

    box-shadow: none;

    margin-bottom: -16px;
}
</style>

Setting the MySQL root user password on OS X

This is what exactly worked for me:

  1. Make sure no other MySQL process is running.To check this do the following:

     a.From the terminal, run this command:
           lsof -i:3306 
       If any PID is returned, kill it using kill -9 PID
     b. Go To System Preferences > MySQL > check if any MySQL instances 
        are running, stop them.
    
  2. Start MySQL with the command:

    sudo /usr/local/mysql/bin/mysqld_safe --skip-grant-tables
    
  3. The password for every user is stored in the mysql.user table under columns User and authentication_string respectively. We can update the table as:

    UPDATE mysql.user SET authentication_string='your_password' where User='root'
    

top align in html table?

<TABLE COLS="3" border="0" cellspacing="0" cellpadding="0">
    <TR style="vertical-align:top">
        <TD>
            <!-- The log text-box -->
            <div style="height:800px; width:240px; border:1px solid #ccc; font:16px/26px Georgia, Garamond, Serif; overflow:auto;">
                Log:
            </div>
        </TD>
        <TD>
            <!-- The 2nd column -->
        </TD>
        <TD>
            <!-- The 3rd column -->
        </TD>
    </TR>
</TABLE>

How to store file name in database, with other info while uploading image to server using PHP?

Adding the following avoids problems with quotes in file names, e.g.

"freddy's pic.jpg"

which are acceptable on some operating systems.

Before:

$pic=($_FILES['photo']['name']);

After:

$pic=(mysql_real_escape_string($_FILES['photo']['name']));

Printing out a number in assembly language?

DOS Print 32 bit value stored in EAX with hexadecimal output (for 80386+)
(on 64 bit OS use DOSBOX)

.code
    mov ax,@DATA        ; get the address of the data segment
    mov ds,ax           ; store the address in the data segment register
;-----------------------
    mov eax,0FFFFFFFFh  ; 32 bit value (0 - FFFFFFFF) for example
;-----------------------
; convert the value in EAX to hexadecimal ASCIIs
;-----------------------
    mov di,OFFSET ASCII ; get the offset address
    mov cl,8            ; number of ASCII
P1: rol eax,4           ; 1 Nibble (start with highest byte)
    mov bl,al
    and bl,0Fh          ; only low-Nibble
    add bl,30h          ; convert to ASCII
    cmp bl,39h          ; above 9?
    jna short P2
    add bl,7            ; "A" to "F"
P2: mov [di],bl         ; store ASCII in buffer
    inc di              ; increase target address
    dec cl              ; decrease loop counter
    jnz P1              ; jump if cl is not equal 0 (zeroflag is not set)
;-----------------------
; Print string
;-----------------------
    mov dx,OFFSET ASCII ; DOS 1+ WRITE STRING TO STANDARD OUTPUT
    mov ah,9            ; DS:DX->'$'-terminated string
    int 21h             ; maybe redirected under DOS 2+ for output to file
                        ; (using pipe character">") or output to printer

  ; terminate program...

.data
ASCII DB "00000000",0Dh,0Ah,"$" ; buffer for ASCII string

Alternative string output directly to the videobuffer without using software interupts:

;-----------------------
; Print string
;-----------------------
    mov ax,0B800h       ; segment address of textmode video buffer
    mov es,ax           ; store address in extra segment register

    mov si,OFFSET ASCII ; get the offset address of the string

; using a fixed target address for example (screen page 0)
; Position`on screen = (Line_number*80*2) + (Row_number*2)

    mov di,(10*80*2)+(10*2)
    mov cl,8            ; number of ASCII
    cld                 ; clear direction flag

P3: lodsb  ; get the ASCII from the address in DS:SI + increase si
    stosb  ; write ASCII directly to the screen using ES:DI + increase di
    inc di ; step over attribut byte
    dec cl ; decrease counter
    jnz P3 ; repeat (print only 8 ASCII, not used bytes are: 0Dh,0Ah,"$")

; Hint: this directly output to the screen do not touch or move the cursor
; but feel free to modify..

Error to run Android Studio

You have 2 things you must check:

  1. verify that /etc/environment file has the correct JAVA_HOME and PATH values referring to your Java installation directory.
  2. verify that you have the correct Java version (maybe you are using a distribution of Linux which need a server version of Java) you may need this version like my case JRE for server.

List files in local git repo?

Try this command:

git ls-files 

This lists all of the files in the repository, including those that are only staged but not yet committed.

http://www.kernel.org/pub/software/scm/git/docs/git-ls-files.html

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

It's a general comparison operator. It returns either a -1, 0, or +1 depending on whether its receiver is less than, equal to, or greater than its argument.

Changing .gitconfig location on Windows

I wanted to do the same thing. The best I could find was @MicTech's solution. However, as pointed out by @MotoWilliams this does not survive any updates made by Git to the .gitconfig file which replaces the link with a new file containing only the new settings.

I solved this by writing the following PowerShell script and running it in my profile startup script. Each time it is run it copies any settings that have been added to the user's .gitconfig to the global one and then replaces all the text in the .gitconfig file with and [include] header that imports the global file.

I keep the global .gitconfig file in a repo along with a lot of other global scripts and tools. All I have to do is remember to check in any changes that the script appends to my global file.

This seems to work pretty transparently for me. Hope it helps!

Sept 9th: Updated to detect when new entries added to the config file are duplicates and ignore them. This is useful for tools like SourceTree which will write new updates if they cannot find existing ones and do not follow includes.

function git-config-update
{
  $localPath = "$env:USERPROFILE\.gitconfig".replace('\', "\\")
  $globalPath = "C:\src\github\Global\Git\gitconfig".replace('\', "\\")

  $redirectAutoText = "# Generated file. Do not edit!`n[include]`n  path = $globalPath`n`n"
  $localText = get-content $localPath

  $diffs = (compare-object -ref $redirectAutoText.split("`n") -diff ($localText) | 
    measure-object).count

  if ($diffs -eq 0)
  {
    write-output ".gitconfig unchanged."
    return
  }

  $skipLines = 0
  $diffs = (compare-object -ref ($redirectAutoText.split("`n") | 
     select -f 3) -diff ($localText | select -f 3) | measure-object).count
  if ($diffs -eq 0)
  {
    $skipLines = 4
    write-warning "New settings appended to $localPath...`n "
  }
  else
  {
    write-warning "New settings found in $localPath...`n "
  }
  $localLines = (get-content $localPath | select -Skip $skipLines) -join "`n"
  $newSettings = $localLines.Split(@("["), [StringSplitOptions]::RemoveEmptyEntries) | 
    where { ![String]::IsNullOrWhiteSpace($_) } | %{ "[$_".TrimEnd() }

  $globalLines = (get-content  $globalPath) -join "`n"
  $globalSettings =  $globalLines.Split(@("["), [StringSplitOptions]::RemoveEmptyEntries)| 
    where { ![String]::IsNullOrWhiteSpace($_) } | %{ "[$_".TrimEnd() }

  $appendSettings = ($newSettings | %{ $_.Trim() } | 
    where { !($globalSettings -contains $_.Trim()) })
  if ([string]::IsNullOrWhitespace($appendSettings))
  {
    write-output "No new settings found."
  }
  else
  {
    echo $appendSettings
    add-content $globalPath ("`n# Additional settings added from $env:COMPUTERNAME on " + (Get-Date -displayhint date) + "`n" + $appendSettings)
  }
  set-content $localPath $redirectAutoText -force
}

How to edit/save a file through Ubuntu Terminal

Open the file using vi or nano. and then press " i " ,

For save and quit

  Enter Esc    

and write the following command

  :wq

without save and quit

  :q!

T-SQL How to select only Second row from a table?

Use TOP 2 in the SELECT to get the desired number of rows in output. This would return in the sequence the data was created. If you have a date option you could order by the date along with TOP n Clause.

To get the top 2 rows;

SELECT TOP 2 [Id] FROM table 

To get the top 2 rows order by some field

SELECT TOP 2 [ID] FROM table ORDER BY <YourColumn> ASC/DESC

To Get only 2nd Row;

WITH Resulttable AS 
( 
  SELECT TOP 2 
    *, ROW_NUMBER() OVER(ORDER BY YourColumn) AS RowNumber 
  FROM @Table 
)  
SELECT *
FROM Resultstable
WHERE RowNumber = 2

How to run crontab job every week on Sunday

Here is an explanation of the crontab format.

# 1. Entry: Minute when the process will be started [0-60]
# 2. Entry: Hour when the process will be started [0-23]
# 3. Entry: Day of the month when the process will be started [1-28/29/30/31]
# 4. Entry: Month of the year when the process will be started [1-12]
# 5. Entry: Weekday when the process will be started [0-6] [0 is Sunday]
#
# all x min = */x

So according to this your 5 8 * * 0 would run 8:05 every Sunday.

Run Python script at startup in Ubuntu

In similar situations, I've done well by putting something like the following into /etc/rc.local:

cd /path/to/my/script
./my_script.py &
cd -
echo `date +%Y-%b-%d_%H:%M:%S` > /tmp/ran_rc_local  # check that rc.local ran

This has worked on multiple versions of Fedora and on Ubuntu 14.04 LTS, for both python and perl scripts.

Transport endpoint is not connected

So interestingly enough this error "Transport endpoint is not connected" was caused by my having more than one Veracrypt device mounted. I closed the extra device and suddenly I had access to the drive. Hmm..

What is the __del__ method, How to call it?

The __del__ method, it will be called when the object is garbage collected. Note that it isn't necessarily guaranteed to be called though. The following code by itself won't necessarily do it:

del obj

The reason being that del just decrements the reference count by one. If something else has a reference to the object, __del__ won't get called.

There are a few caveats to using __del__ though. Generally, they usually just aren't very useful. It sounds to me more like you want to use a close method or maybe a with statement.

See the python documentation on __del__ methods.

One other thing to note: __del__ methods can inhibit garbage collection if overused. In particular, a circular reference that has more than one object with a __del__ method won't get garbage collected. This is because the garbage collector doesn't know which one to call first. See the documentation on the gc module for more info.

JavaScript - Getting HTML form values

Here is an example from W3Schools:

function myFunction() {
    var elements = document.getElementById("myForm").elements;
    var obj ={};
    for(var i = 0 ; i < elements.length ; i++){
        var item = elements.item(i);
        obj[item.name] = item.value;
    }

    document.getElementById("demo").innerHTML = JSON.stringify(obj);
}

The demo can be found here.

How do I upload a file with the JS fetch API?

An important note for sending Files with Fetch API

One needs to omit content-type header for the Fetch request. Then the browser will automatically add the Content type header including the Form Boundary which looks like

Content-Type: multipart/form-data; boundary=—-WebKitFormBoundaryfgtsKTYLsT7PNUVD

Form boundary is the delimiter for the form data

How can I change the default Mysql connection timeout when connecting through python?

MAX_EXECUTION_TIME is also an important parameter for long running queries.Will work for MySQL 5.7 or later.

Check the current value

SELECT @@GLOBAL.MAX_EXECUTION_TIME, @@SESSION.MAX_EXECUTION_TIME;

Then set it according to your needs.

SET SESSION MAX_EXECUTION_TIME=2000;
SET GLOBAL MAX_EXECUTION_TIME=2000;

Convert column classes in data.table

Here is the same way as @Nera suggested to check the class first but instead of using .SD is to use the fast loop of data.table with set as @Matt Dowle solution with added class check.

for (j in seq_len(ncol(DT))){
  if(class(DT[[j]]) == 'factor')
    set(DT, j = j, value = as.character(DT[[j]]))
}

Path.Combine absolute with relative path strings

This will give you exactly what you need (path does NOT have to exist for this to work)

DirectoryInfo di = new DirectoryInfo(@"C:\blah\..\bling");
string cleanPath = di.FullName;

Converting unix time into date-time via excel

  • To convert the epoch(Unix-Time) to regular time like for the below timestamp

    Ex: 1517577336206

  • First convert the value with the following function like below

    =LEFT(A1,10) & "." & RIGHT(A1,3)

  • The output will be like below

    Ex: 1517577336.206

  • Now Add the formula like below

    =(((B1/60)/60)/24)+DATE(1970,1,1)

  • Now format the cell like below or required format(Custom format)

    m/d/yyyy h:mm:ss.000

Now example time comes like

2/2/2018 13:15:36.206

The three zeros are for milliseconds

Python regex to match dates

Instead of using regex, it is generally better to parse the string as a datetime.datetime object:

In [140]: datetime.datetime.strptime("11/12/98","%m/%d/%y")
Out[140]: datetime.datetime(1998, 11, 12, 0, 0)

In [141]: datetime.datetime.strptime("11/12/98","%d/%m/%y")
Out[141]: datetime.datetime(1998, 12, 11, 0, 0)

You could then access the day, month, and year (and hour, minutes, and seconds) as attributes of the datetime.datetime object:

In [143]: date.year
Out[143]: 1998

In [144]: date.month
Out[144]: 11

In [145]: date.day
Out[145]: 12

To test if a sequence of digits separated by forward-slashes represents a valid date, you could use a try..except block. Invalid dates will raise a ValueError:

In [159]: try:
   .....:     datetime.datetime.strptime("99/99/99","%m/%d/%y")
   .....: except ValueError as err:
   .....:     print(err)
   .....:     
   .....:     
time data '99/99/99' does not match format '%m/%d/%y'

If you need to search a longer string for a date, you could use regex to search for digits separated by forward-slashes:

In [146]: import re
In [152]: match = re.search(r'(\d+/\d+/\d+)','The date is 11/12/98')

In [153]: match.group(1)
Out[153]: '11/12/98'

Of course, invalid dates will also match:

In [154]: match = re.search(r'(\d+/\d+/\d+)','The date is 99/99/99')

In [155]: match.group(1)
Out[155]: '99/99/99'

To check that match.group(1) returns a valid date string, you could then parsing it using datetime.datetime.strptime as shown above.

How to find out the username and password for mysql database

Assuming that the user you are using in phpmyadmin has the necessary privileges, you can run this query to change the root password:

UPDATE mysql.user SET Password=PASSWORD('MyNewPass') WHERE User='root';
FLUSH PRIVILEGES;

android - save image into gallery

You can create a directory inside the camera folder and save the image. After that, you can simply perform your scan. It will instantly show your image in the gallery.

String root = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM).toString()+ "/Camera/Your_Directory_Name";
File myDir = new File(root);
myDir.mkdirs();
String fname = "Image-" + image_name + ".png";
File file = new File(myDir, fname);
System.out.println(file.getAbsolutePath());
if (file.exists()) file.delete();
    Log.i("LOAD", root + fname);
    try {
        FileOutputStream out = new FileOutputStream(file);
        finalBitmap.compress(Bitmap.CompressFormat.PNG, 90, out);
        out.flush();
        out.close();
    } catch (Exception e) {
       e.printStackTrace();
    }

MediaScannerConnection.scanFile(context, new String[]{file.getPath()}, new String[]{"image/jpeg"}, null);

Laravel Update Query

It is very simple to do. Code are given below :

 DB::table('user')->where('email', $userEmail)->update(array('member_type' => $plan));  

The provided URI scheme 'https' is invalid; expected 'http'. Parameter name: via

I had the EXACT same issue as the OP. My configuration and situation were identical. I finally narrowed it down to being an issue in WCFStorm after creating a service reference in a test project in Visual Studio and confirming that the service was working. In Storm you need to click on the "Config" settings option (NOT THE "Client Config"). After clicking on that, click on the "Security" tab on the dialog that pops up. Make sure "Authentication Type" is set to "None" (The default is "Windows Authentication"). Presto, it works! I always test out my methods in WCFStorm as I'm building them out, but have never tried using it to connect to one that has already been set up on SSL. Hope this helps someone!

Is there any difference between "!=" and "<>" in Oracle Sql?

No there is no difference at all in functionality.
(The same is true for all other DBMS - most of them support both styles):

Here is the current SQL reference: https://docs.oracle.com/database/121/SQLRF/conditions002.htm#CJAGAABC

The SQL standard only defines a single operator for "not equals" and that is <>

Can Console.Clear be used to only clear a line instead of whole console?

public static void ClearLine(int lines = 1)
{
    for (int i = 1; i <= lines; i++)
    {
        Console.SetCursorPosition(0, Console.CursorTop - 1);
        Console.Write(new string(' ', Console.WindowWidth));
        Console.SetCursorPosition(0, Console.CursorTop - 1);
    }
}

How to execute 16-bit installer on 64-bit Win7?

16 bit installer will not work on windows 7 it's no longer supported by win 7 the most recent supported version of windows that can run 16 bit installer is vista 32-bit even vista 64-bit doesn't support 16-bit installer.... reference http://support.microsoft.com/kb/946765

What is the meaning of "Failed building wheel for X" in pip install?

I had the same problem while installing Brotli

ERROR

Failed building wheel for Brotli

I solved it by downloading the .whl file from here and installing it using the below command

C:\Users\{user_name}\Downloads>pip install Brotli-1.0.9-cp39-cp39-win_amd64.whl

AngularJS : Initialize service with asynchronous data

Easiest way to fetch any initialize use ng-init directory.

Just put ng-init div scope where you want to fetch init data

index.html

<div class="frame" ng-init="init()">
    <div class="bit-1">
      <div class="field p-r">
        <label ng-show="regi_step2.address" class="show-hide c-t-1 ng-hide" style="">Country</label>
        <select class="form-control w-100" ng-model="country" name="country" id="country" ng-options="item.name for item in countries" ng-change="stateChanged()" >
        </select>
        <textarea class="form-control w-100" ng-model="regi_step2.address" placeholder="Address" name="address" id="address" ng-required="true" style=""></textarea>
      </div>
    </div>
  </div>

index.js

$scope.init=function(){
    $http({method:'GET',url:'/countries/countries.json'}).success(function(data){
      alert();
           $scope.countries = data;
    });
  };

NOTE: you can use this methodology if you do not have same code more then one place.

How do I execute cmd commands through a batch file?

@echo off
title Command Executer
color 1b

echo Command Executer by: YourNameHere
echo #################################
: execute
echo Please Type A Command Here:
set /p cmd=Command:
%cmd%
goto execute

Accessing all items in the JToken

If you know the structure of the json that you're receiving then I'd suggest having a class structure that mirrors what you're receiving in json.

Then you can call its something like this...

AddressMap addressMap = JsonConvert.DeserializeObject<AddressMap>(json);

(Where json is a string containing the json in question)

If you don't know the format of the json you've receiving then it gets a bit more complicated and you'd probably need to manually parse it.

check out http://www.hanselman.com/blog/NuGetPackageOfTheWeek4DeserializingJSONWithJsonNET.aspx for more info

git clone error: RPC failed; curl 56 OpenSSL SSL_read: SSL_ERROR_SYSCALL, errno 10054

git config --global http.postBuffer 524288000

Work in my case - AWS code commit

How to avoid HTTP error 429 (Too Many Requests) python

As MRA said, you shouldn't try to dodge a 429 Too Many Requests but instead handle it accordingly. You have several options depending on your use-case:

1) Sleep your process. The server usually includes a Retry-after header in the response with the number of seconds you are supposed to wait before retrying. Keep in mind that sleeping a process might cause problems, e.g. in a task queue, where you should instead retry the task at a later time to free up the worker for other things.

2) Exponential backoff. If the server does not tell you how long to wait, you can retry your request using increasing pauses in between. The popular task queue Celery has this feature built right-in.

3) Token bucket. This technique is useful if you know in advance how many requests you are able to make in a given time. Each time you access the API you first fetch a token from the bucket. The bucket is refilled at a constant rate. If the bucket is empty, you know you'll have to wait before hitting the API again. Token buckets are usually implemented on the other end (the API) but you can also use them as a proxy to avoid ever getting a 429 Too Many Requests. Celery's rate_limit feature uses a token bucket algorithm.

Here is an example of a Python/Celery app using exponential backoff and rate-limiting/token bucket:

class TooManyRequests(Exception):
"""Too many requests"""

@task(
   rate_limit='10/s',
   autoretry_for=(ConnectTimeout, TooManyRequests,),
   retry_backoff=True)
def api(*args, **kwargs):
  r = requests.get('placeholder-external-api')

  if r.status_code == 429:
    raise TooManyRequests()

How do I programmatically click a link with javascript?

If you only want to change the current page address, you can do that by simply doing this in Javascript :

location.href = "http://www.example.com/test";

How to clear Tkinter Canvas?

Every canvas item is an object that Tkinter keeps track of. If you are clearing the screen by just drawing a black rectangle, then you effectively have created a memory leak -- eventually your program will crash due to the millions of items that have been drawn.

To clear a canvas, use the delete method. Give it the special parameter "all" to delete all items on the canvas (the string "all"" is a special tag that represents all items on the canvas):

canvas.delete("all")

If you want to delete only certain items on the canvas (such as foreground objects, while leaving the background objects on the display) you can assign tags to each item. Then, instead of "all", you could supply the name of a tag.

If you're creating a game, you probably don't need to delete and recreate items. For example, if you have an object that is moving across the screen, you can use the move or coords method to move the item.

jQuery issue in Internet Explorer 8

If you are using HTTPS on your site, you will need to load the jQuery library from Googles https server instead. Try this: https://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js (or the latest https://ajax.googleapis.com/ajax/libs/jquery/1.5.1/jquery.min.js)

How to retrieve form values from HTTPPOST, dictionary or?

You could have your controller action take an object which would reflect the form input names and the default model binder will automatically create this object for you:

[HttpPost]
public ActionResult SubmitAction(SomeModel model)
{
    var value1 = model.SimpleProp1;
    var value2 = model.SimpleProp2;
    var value3 = model.ComplexProp1.SimpleProp1;
    ...

    ... return something ...
}

Another (obviously uglier) way is:

[HttpPost]
public ActionResult SubmitAction()
{
    var value1 = Request["SimpleProp1"];
    var value2 = Request["SimpleProp2"];
    var value3 = Request["ComplexProp1.SimpleProp1"];
    ...

    ... return something ...
}

What is “assert” in JavaScript?

Here is a really simple implementation of an assert function. It takes a value and a description of what you are testing.

 function assert(value, description) {
        var result = value ? "pass" : "fail";
        console.log(result + ' - ' +  description); 
    };

If the value evaluates to true it passes.

assert (1===1, 'testing if 1=1');  

If it returns false it fails.

assert (1===2, 'testing if 1=1');

How to get info on sent PHP curl request

curl_getinfo() must be added before closing the curl handler

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "http://example.com/bar");
curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
curl_setopt($ch, CURLOPT_USERPWD, "someusername:secretpassword");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLINFO_HEADER_OUT, true);
curl_exec($ch);
$info = curl_getinfo($ch);
print_r($info['request_header']);
curl_close($ch);

How do I declare a two dimensional array?

$r = array("arr1","arr2");

to echo a single array element you should write:

echo $r[0];
echo $r[1];

output would be: arr1 arr2

Change tab bar tint color on iOS 7

In app delegate didFinishLaunchingWithOptions:

window.tintColor = [UIColor purpleColor];

sets the tint color globally for the app.

Getting the class name from a static method in Java

A refactoring-safe, cut&paste-safe solution that avoids the definition of ad-hoc classes below.

Write a static method that recover the class name having care to include the class name in the method name:

private static String getMyClassName(){
  return MyClass.class.getName();
}

then recall it in your static method:

public static void myMethod(){
  Tracer.debug(getMyClassName(), "message");
}

Refactoring safety is given by avoiding the use of strings, cut&paste safety is granted because if you cut&paste the caller method you won't find the getMyClassName() in the target "MyClass2" class, so you will be forced to redefine and update it.

How to count string occurrence in string?

Here is the fastest function!

Why is it faster?

  • Doesn't check char by char (with 1 exception)
  • Uses a while and increments 1 var (the char count var) vs. a for loop checking the length and incrementing 2 vars (usually var i and a var with the char count)
  • Uses WAY less vars
  • Doesn't use regex!
  • Uses an (hopefully) highly optimized function
  • All operations are as combined as they can be, avoiding slowdowns due to multiple operations

    String.prototype.timesCharExist=function(c){var t=0,l=0,c=(c+'')[0];while(l=this.indexOf(c,l)+1)++t;return t};
    

Here is a slower and more readable version:

    String.prototype.timesCharExist = function ( chr ) {
        var total = 0, last_location = 0, single_char = ( chr + '' )[0];
        while( last_location = this.indexOf( single_char, last_location ) + 1 )
        {
            total = total + 1;
        }
        return total;
    };

This one is slower because of the counter, long var names and misuse of 1 var.

To use it, you simply do this:

    'The char "a" only shows up twice'.timesCharExist('a');

Edit: (2013/12/16)

DON'T use with Opera 12.16 or older! it will take almost 2.5x more than the regex solution!

On chrome, this solution will take between 14ms and 20ms for 1,000,000 characters.

The regex solution takes 11-14ms for the same amount.

Using a function (outside String.prototype) will take about 10-13ms.

Here is the code used:

    String.prototype.timesCharExist=function(c){var t=0,l=0,c=(c+'')[0];while(l=this.indexOf(c,l)+1)++t;return t};

    var x=Array(100001).join('1234567890');

    console.time('proto');x.timesCharExist('1');console.timeEnd('proto');

    console.time('regex');x.match(/1/g).length;console.timeEnd('regex');

    var timesCharExist=function(x,c){var t=0,l=0,c=(c+'')[0];while(l=x.indexOf(c,l)+1)++t;return t;};

    console.time('func');timesCharExist(x,'1');console.timeEnd('func');

The result of all the solutions should be 100,000!

Note: if you want this function to count more than 1 char, change where is c=(c+'')[0] into c=c+''

Call a stored procedure with parameter in c#

It's pretty much the same as running a query. In your original code you are creating a command object, putting it in the cmd variable, and never use it. Here, however, you will use that instead of da.InsertCommand.

Also, use a using for all disposable objects, so that you are sure that they are disposed properly:

private void button1_Click(object sender, EventArgs e) {
  using (SqlConnection con = new SqlConnection(dc.Con)) {
    using (SqlCommand cmd = new SqlCommand("sp_Add_contact", con)) {
      cmd.CommandType = CommandType.StoredProcedure;

      cmd.Parameters.Add("@FirstName", SqlDbType.VarChar).Value = txtFirstName.Text;
      cmd.Parameters.Add("@LastName", SqlDbType.VarChar).Value = txtLastName.Text;

      con.Open();
      cmd.ExecuteNonQuery();
    }
  }
}

Handling of non breaking space: <p>&nbsp;</p> vs. <p> </p>

In HTML, elements containing nothing but normal whitespace characters are considered empty. A paragraph that contains just a normal space character will have zero height. A non-breaking space is a special kind of whitespace character that isn't considered to be insignificant, so it can be used as content for a non-empty paragraph.

Even if you consider CSS margins on paragraphs, since an "empty" paragraph has zero height, its vertical margins will collapse. This causes it to have no height and no margins, making it appear as if it were never there at all.

For..In loops in JavaScript - key value pairs

let test = {a: 1, b: 2, c: 3};
Object.entries(test).forEach(([key, value]) => console.log(key, value))

// a 1
// b 2
// c 3

How to delete a remote tag?

Delete all local tags and get the list of remote tags:

git tag -l | xargs git tag -d
git fetch

Remove all remote tags

git tag -l | xargs -n 1 git push --delete origin

Clean up local tags

git tag -l | xargs git tag -d

Understanding The Modulus Operator %

A novel way to find out the remainder is given below

Statement : Remainder is always constant

ex : 26 divided by 7 gives R : 5 

This can be found out easily by finding the number that completely divides 26 which is closer to the divisor and taking the difference of the both

13 is the next number after 7 that completely divides 26 because after 7 comes 8, 9, 10, 11, 12 where none of them divides 26 completely and give remainder 0.

So 13 is the closest number to 7 which divides to give remainder 0.

Now take the difference (13 ~ 7) = 5 which is the temainder.

Note: for this to work divisor should be reduced to its simplest form ex: if 14 is the divisor, 7 has to be chosen to find the closest number dividing the dividend.

How do I pass a class as a parameter in Java?

public void callingMethod(Class neededClass) {
    //Cast the class to the class you need
    //and call your method in the class
    ((ClassBeingCalled)neededClass).methodOfClass();
}

To call the method, you call it this way:

callingMethod(ClassBeingCalled.class);

What is the easiest way to get current GMT time in Unix timestamp format?

from datetime import datetime as dt
dt.utcnow().strftime("%s")

Output:

1544524990

How do I disable a Pylint warning?

Starting from Pylint v. 0.25.3, you can use the symbolic names for disabling warnings instead of having to remember all those code numbers. E.g.:

# pylint: disable=locally-disabled, multiple-statements, fixme, line-too-long

This style is more instructive than cryptic error codes, and also more practical since newer versions of Pylint only output the symbolic name, not the error code.

The correspondence between symbolic names and codes can be found here.

A disable comment can be inserted on its own line, applying the disable to everything that comes after in the same block. Alternatively, it can be inserted at the end of the line for which it is meant to apply.

If Pylint outputs "Locally disabling" messages, you can get rid of them by including the disable locally-disabled first as in the example above.

Excel VBA: AutoFill Multiple Cells with Formulas

Based on my Comment here is one way to get what you want done:

Start byt selecting any cell in your range and Press Ctrl + T

This will give you this pop up:

enter image description here

make sure the Where is your table text is correct and click ok you will now have:

enter image description here

Now If you add a column header in D it will automatically be added to the table all the way to the last row:

enter image description here

Now If you enter a formula into this column:

enter image description here

After you enter it, the formula will be auto filled all the way to last row:

enter image description here

Now if you add a new row at the next row under your table:

enter image description here

Once entered it will be resized to the width of your table and all columns with formulas will be added also:

enter image description here

Hope this solves your problem!

Mockito match any class argument

How about:

when(a.method(isA(A.class))).thenReturn(b);

or:

when(a.method((A)notNull())).thenReturn(b);

How to store a dataframe using Pandas

The easiest way is to pickle it using to_pickle:

df.to_pickle(file_name)  # where to save it, usually as a .pkl

Then you can load it back using:

df = pd.read_pickle(file_name)

Note: before 0.11.1 save and load were the only way to do this (they are now deprecated in favor of to_pickle and read_pickle respectively).


Another popular choice is to use HDF5 (pytables) which offers very fast access times for large datasets:

import pandas as pd
store = pd.HDFStore('store.h5')

store['df'] = df  # save it
store['df']  # load it

More advanced strategies are discussed in the cookbook.


Since 0.13 there's also msgpack which may be be better for interoperability, as a faster alternative to JSON, or if you have python object/text-heavy data (see this question).

How to use Bootstrap 4 in ASP.NET Core

Unfortunately, you're going to have a hard time using NuGet to install Bootstrap (or most other JavaScript/CSS frameworks) on a .NET Core project. If you look at the NuGet install it tells you it is incompatible:

enter image description here

if you must know where local packages dependencies are, they are now in your local profile directory. i.e. %userprofile%\.nuget\packages\bootstrap\4.0.0\content\Scripts.

However, I suggest switching to npm, or bower - like in Saineshwar's answer.

WCF change endpoint address at runtime

So your endpoint address defined in your first example is incomplete. You must also define endpoint identity as shown in client configuration. In code you can try this:

EndpointIdentity spn = EndpointIdentity.CreateSpnIdentity("host/mikev-ws");
var address = new EndpointAddress("http://id.web/Services/EchoService.svc", spn);   
var client = new EchoServiceClient(address); 
litResponse.Text = client.SendEcho("Hello World"); 
client.Close();

Actual working final version by valamas

EndpointIdentity spn = EndpointIdentity.CreateSpnIdentity("host/mikev-ws");
Uri uri = new Uri("http://id.web/Services/EchoService.svc");
var address = new EndpointAddress(uri, spn);
var client = new EchoServiceClient("WSHttpBinding_IEchoService", address);
client.SendEcho("Hello World");
client.Close(); 

Python: "TypeError: __str__ returned non-string" but still prints to output?

You can also surround the output with str(). I had this same problem because my model had the following (as a simplified example):

def __str__(self):
    return self.pressid

Where pressid was an IntegerField type object. Django (and python in general) expects a string for a str function, so returning an integer causes this error to be thrown.

def __str__(self):
    return str(self.pressid)

That solved the problems I was encountering on the Django management side of the house. Hope it helps with yours.

How to exit git log or git diff

The END comes from the pager used to display the log (your are at that moment still inside it). Type q to exit it.

Populating a data frame in R in a loop

I had a case in where I was needing to use a data frame within a for loop function. In this case, it was the "efficient", however, keep in mind that the database was small and the iterations in the loop were very simple. But maybe the code could be useful for some one with similar conditions.

The for loop purpose was to use the raster extract function along five locations (i.e. 5 Tokio, New York, Sau Paulo, Seul & Mexico city) and each location had their respective raster grids. I had a spatial point database with more than 1000 observations allocated within the 5 different locations and I was needing to extract information from 10 different raster grids (two grids per location). Also, for the subsequent analysis, I was not only needing the raster values but also the unique ID for each observations.

After preparing the spatial data, which included the following tasks:

  1. Import points shapefile with the readOGR function (rgdap package)
  2. Import raster files with the raster function (raster package)
  3. Stack grids from the same location into one file, with the function stack (raster package)

Here the for loop code with the use of a data frame:

1. Add stacked rasters per location into a list

raslist <- list(LOC1,LOC2,LOC3,LOC4,LOC5)

2. Create an empty dataframe, this will be the output file

TB <- data.frame(VAR1=double(),VAR2=double(),ID=character())

3. Set up for loop function

L1 <- seq(1,5,1) # the location ID is a numeric variable with values from 1 to 5 

for (i in 1:length(L1)) {
  dat=subset(points,LOCATION==i) # select corresponding points for location [i] 
  t=data.frame(extract(raslist[[i]],dat),dat$ID) # run extract function with points & raster stack for location [i]
  names(t)=c("VAR1","VAR2","ID") 
  TB=rbind(TB,t)
}

How to convert integer to string in C?

That's because itoa isn't a standard function. Try snprintf instead.

char str[LEN];
snprintf(str, LEN, "%d", 42);

How to use *ngIf else?

ngif expression resulting value won’t just be the boolean true or false

if the expression is just a object, it still evaluate it as truthiness.

if the object is undefined, or non-exist, then ngif will evaluate it as falseness.

common use is if an object loaded, exist, then display the content of this object, otherwise display "loading.......".

 <div *ngIf="!object">
     Still loading...........
 </div>

<div *ngIf="object">
     <!-- the content of this object -->

           object.info, object.id, object.name ... etc.
 </div>

another example:

  things = {
 car: 'Honda',
 shoes: 'Nike',
 shirt: 'Tom Ford',
 watch: 'Timex'
 };

 <div *ngIf="things.car; else noCar">
  Nice car!
 </div>

<ng-template #noCar>
   Call a Uber.
</ng-template>

 <!-- Nice car ! -->

anthoer example:

<div *ngIf="things.car; let car">
   Nice {{ car }}!
 </div>
<!-- Nice Honda! -->

ngif template

ngif angular 4

Check if a String is in an ArrayList of Strings

    List list1 = new ArrayList();
    list1.add("one");
    list1.add("three");
    list1.add("four");

    List list2 = new ArrayList();
    list2.add("one");
    list2.add("two");
    list2.add("three");
    list2.add("four");
    list2.add("five");


    list2.stream().filter( x -> !list1.contains(x) ).forEach(x -> System.out.println(x));

The output is:

two
five

Pass parameter to EventHandler

Timer.Elapsed expects method of specific signature (with arguments object and EventArgs). If you want to use your PlayMusicEvent method with additional argument evaluated during event registration, you can use lambda expression as an adapter:

myTimer.Elapsed += new ElapsedEventHandler((sender, e) => PlayMusicEvent(sender, e, musicNote));

Edit: you can also use shorter version:

myTimer.Elapsed += (sender, e) => PlayMusicEvent(sender, e, musicNote);

How to create a HTML Table from a PHP array?

echo '<table><tr><th>Title</th><th>Price</th><th>Number</th></tr>';
foreach($shop as $id => $item) {
    echo '<tr><td>'.$item[0].'</td><td>'.$item[1].'</td><td>'.$item[2].'</td></tr>';
}
echo '</table>';

How do I join two lists in Java?

Another Java 8 one-liner:

List<String> newList = Stream.of(listOne, listTwo)
                            .flatMap(Collection::stream)
                            .collect(Collectors.toList());

As a bonus, since Stream.of() is variadic, you may concatenate as many lists as you like.

List<String> newList = Stream.of(listOne, listTwo, listThree)
                            .flatMap(Collection::stream)
                            .collect(Collectors.toList());

how to check if string contains '+' character

You need this instead:

if(s.contains("+"))

contains() method of String class does not take regular expression as a parameter, it takes normal text.


EDIT:

String s = "ddjdjdj+kfkfkf";

if(s.contains("+"))
{
    String parts[] = s.split("\\+");
    System.out.print(parts[0]);
}

OUTPUT:

ddjdjdj

how to create a cookie and add to http response from inside my service layer?

In Spring MVC you get the HtppServletResponce object by default .

   @RequestMapping("/myPath.htm")
    public ModelAndView add(HttpServletRequest request,
         HttpServletResponse response) throws Exception{
            //Do service call passing the response
    return new ModelAndView("CustomerAddView");
    }

//Service code
Cookie myCookie =
  new Cookie("name", "val");
  response.addCookie(myCookie);

PHP Warning: Module already loaded in Unknown on line 0

I deleted the 20-mongo.ini file in /etc/php5/cli/conf.d and this solved the problem.

what innerHTML is doing in javascript?

The innerHTML property is part of the Document Object Model (DOM) that allows Javascript code to manipulate a website being displayed. Specifically, it allows reading and replacing everything within a given DOM element (HTML tag).

However, DOM manipulations using innerHTML are slower and more failure-prone than manipulations based on individual DOM objects.

HTML favicon won't show on google chrome

Your html is completely wrong for starters, there should not be a div within your head section, nor after your body section. I suggest you look into correct html first before starting to work with favicons etc.

pandas dataframe create new columns and fill with calculated values from same df

In [56]: df = pd.DataFrame(np.abs(randn(3, 4)), index=[1,2,3], columns=['A','B','C','D'])

In [57]: df.divide(df.sum(axis=1), axis=0)
Out[57]: 
          A         B         C         D
1  0.319124  0.296653  0.138206  0.246017
2  0.376994  0.326481  0.230464  0.066062
3  0.036134  0.192954  0.430341  0.340571

symfony 2 twig limit the length of the text and put three dots

@olegkhuss solution with named UTF-8 Elipsis: {{ (my.text|length > 50 ? my.text|slice(0, 50) ~ '…' : my.text) }}

How much memory can a 32 bit process access on a 64 bit operating system?

An single 32-bit process under a 64-bit OS is limited to 2Gb. But if it is compiled to an EXE file with IMAGE_FILE_LARGE_ADDRESS_AWARE bit set, it then has a limit of 4 GB, not 2Gb - see https://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx

The things you hear about special boot flags, 3 GB, /3GB switches, or /userva are all about 32-bit operating systems and do not apply on 64-bit Windows.

See https://msdn.microsoft.com/en-us/library/aa366778(v=vs.85).aspx for more details.

As about the 32-bit operating systems, contrary to the belief, there is no physical limit of 4GB for 32-bit operating systems. For example, 32-bit Server Operating Systems like Microsoft Windows Server 2008 32-bit can access up to 64 GB (Windows Server 2008 Enterprise and Datacenter editions) – by means of Physical Address Extension (PAE), which was first introduced by Intel in the Pentium Pro, and later by AMD in the Athlon processor - it defines a page table hierarchy of three levels, with table entries of 64 bits each instead of 32, allowing these CPUs to directly access a physical address space larger than 4 gigabytes – so theoretically, a 32-bit OS can access 2^64 bytes theoretically, or 17,179,869,184 gigabytes, but the segment is limited by 4GB. However, due to marketing reasons, Microsoft have limited maximum accessible memory on non-server operating systems to just 4GB, or, even, 3GB effectively. Thus, a single process can access more than 4GB on a 32-bit OS - and Microsoft SQL server is an example.

32-bit processes under 64-bit Windows do not have any disadvantage comparing to 64-bit processes in using shared kernel's virtual address space (also called system space). All processes, be it 64-bit or 32-bit, under 64-bit Windows share the same 64-bit system space.

Given the fact that the system space is shared across all processes, on 32-bit Windows, processes that create large amount of handles (like threads, semaphores, files, etc.) consume system space by kernel objects and can run out of memory even if you have lot of memory available in total. In contrast, on 64-bit Windows, the kernel space is 64-bit and is not limited by 4 GB. All system calls made by 32-bit applications are converted to native 64-bit calls in the user mode.

VB.NET - Click Submit Button on Webbrowser page

You could try giving an ID to the form, in order to get ahold of it, and then call form.submit() from a Javascript call.

std::cin input with spaces?

THE C WAY

You can use gets function found in cstdio(stdio.h in c):

#include<cstdio>
int main(){

char name[256];
gets(name); // for input
puts(name);// for printing 
}

THE C++ WAY

gets is removed in c++11.

[Recommended]:You can use getline(cin,name) which is in string.h or cin.getline(name,256) which is in iostream itself.

#include<iostream>
#include<string>
using namespace std;
int main(){

char name1[256];
string name2;
cin.getline(name1,256); // for input
getline(cin,name2); // for input
cout<<name1<<"\n"<<name2;// for printing
}

What's the difference between HEAD, working tree and index, in Git?

Working tree

Your working tree are the files that you are currently working on.

Git index

  • The git "index" is where you place files you want commit to the git repository.

  • The index is also known as cache, directory cache, current directory cache, staging area, staged files.

  • Before you "commit" (checkin) files to the git repository, you need to first place the files in the git "index".

  • The index is not the working directory: you can type a command such as git status, and git will tell you what files in your working directory have been added to the git index (for example, by using the git add filename command).

  • The index is not the git repository: files in the git index are files that git would commit to the git repository if you used the git commit command.

How to add a class to a given element?

To add, remove or check element classes in a simple way:

var uclass = {
    exists: function(elem,className){var p = new RegExp('(^| )'+className+'( |$)');return (elem.className && elem.className.match(p));},
    add: function(elem,className){if(uclass.exists(elem,className)){return true;}elem.className += ' '+className;},
    remove: function(elem,className){var c = elem.className;var p = new RegExp('(^| )'+className+'( |$)');c = c.replace(p,' ').replace(/  /g,' ');elem.className = c;}
};

var elem = document.getElementById('someElem');
//Add a class, only if not exists yet.
uclass.add(elem,'someClass');
//Remove class
uclass.remove(elem,'someClass');

Basic CSS - how to overlay a DIV with semi-transparent DIV on top

For a div-Element you could just set the opacity via a class to enable or disable the effect.

.mute-all {
   opacity: 0.4;
}

Index inside map() function

Array.prototype.map() index:

One can access the index Array.prototype.map() via the second argument of the callback function. Here is an example:

_x000D_
_x000D_
const array = [1, 2, 3, 4];_x000D_
_x000D_
_x000D_
const map = array.map((x, index) => {_x000D_
  console.log(index);_x000D_
  return x + index;_x000D_
});_x000D_
_x000D_
console.log(map);
_x000D_
_x000D_
_x000D_

Other arguments of Array.prototype.map():

  • The third argument of the callback function exposes the array on which map was called upon
  • The second argument of Array.map() is a object which will be the this value for the callback function. Keep in mind that you have to use the regular function keyword in order to declare the callback since an arrow function doesn't have its own binding to the this keyword.

For example:

_x000D_
_x000D_
const array = [1, 2, 3, 4];_x000D_
_x000D_
const thisObj = {prop1: 1}_x000D_
_x000D_
_x000D_
const map = array.map( function (x, index, array) {_x000D_
  console.log(array);_x000D_
  console.log(this)_x000D_
}, thisObj);
_x000D_
_x000D_
_x000D_

SQL RANK() over PARTITION on joined tables

As the rank doesn't depend at all from the contacts

RANKED_RSLTS

 QRY_ID  |  RES_ID  |  SCORE |  RANK
-------------------------------------
   A     |    1     |    15  |   3
   A     |    2     |    32  |   1
   A     |    3     |    29  |   2
   C     |    7     |    61  |   1
   C     |    9     |    30  |   2

Thus :

SELECT
    C.*
    ,R.SCORE
    ,MYRANK
FROM CONTACTS C LEFT JOIN
(SELECT  *,
 MYRANK = RANK() OVER (PARTITION BY QRY_ID ORDER BY SCORE DESC)
  FROM RSLTS)  R
ON C.RES_ID = R.RES_ID
AND C.QRY_ID = R.QRY_ID

How do you add an image?

The other option to try is a straightforward

<img width="100" height="100" src="/root/Image/image.jpeg" class="CalloutRightPhoto"/>

i.e. without {} but instead giving the direct image path

How to convert NSNumber to NSString

Try:

NSString *myString = [NSNumber stringValue];

How do I check/uncheck all checkboxes with a button using jQuery?

$(function () {
    $('input#check_all').change(function () {
        $("input[name='input_ids[]']").prop('checked', $(this).prop("checked"));
    });
});

How can I find out a file's MIME type (Content-Type)?

file --mime works, but not --mime-type. at least for my RHEL 5.

Jackson and generic type reference

This is a well-known problem with Java type erasure: T is just a type variable, and you must indicate actual class, usually as Class argument. Without such information, best that can be done is to use bounds; and plain T is roughly same as 'T extends Object'. And Jackson will then bind JSON Objects as Maps.

In this case, tester method needs to have access to Class, and you can construct

JavaType type = mapper.getTypeFactory().
  constructCollectionType(List.class, Foo.class)

and then

List<Foo> list = mapper.readValue(new File("input.json"), type);

Use ffmpeg to add text subtitles

I will provide a simple and general answer that works with any number of audios and srt subtitles and respects the metadata that may include the mkv container. So it will even add the images the matroska may include as attachments (though not another types AFAIK) and convert them to tracks; you will not be able to watch but they will be there (you can demux them). Ah, and if the mkv has chapters the mp4 too.

ffmpeg -i <mkv-input> -c copy -map 0 -c:s mov_text <mp4-output>

As you can see, it's all about the -map 0, that tells FFmpeg to add all the tracks, which includes metadata, chapters, attachments, etc. If there is an unrecognized "track" (mkv allows to attach any type of file), it will end with an error.

You can create a simple batch mkv2mp4.bat, if you usually do this, to create an mp4 with the same name as the mkv. It would be better with error control, a different output name, etc., but you get the point.

@ffmpeg -i %1 -c copy -map 0 -c:s mov_text "%~n1.mp4"

Now you can simply run

mkv2mp4 "Video with subtitles etc.mkv"

And it will create "Video with subtitles etc.mp4" with the maximum of information included.

How to get week number in Python?

Generally to get the current week number (starts from Sunday):

from datetime import *
today = datetime.today()
print today.strftime("%U")

Time complexity of nested for-loop

On the 1st iteration of the outer loop (i = 1), the inner loop will iterate 1 times On the 2nd iteration of the outer loop (i = 2), the inner loop will iterate 2 time On the 3rd iteration of the outer loop (i = 3), the inner loop will iterate 3 times
.
.
On the FINAL iteration of the outer loop (i = n), the inner loop will iterate n times

So, the total number of times the statements in the inner loop will be executed will be equal to the sum of the integers from 1 to n, which is:

((n)*n) / 2 = (n^2)/2 = O(n^2) times 

PUT vs. POST in REST

Here's a simple rule:

PUT to a URL should be used to update or create the resource that can be located at that URL.

POST to a URL should be used to update or create a resource which is located at some other ("subordinate") URL, or is not locatable via HTTP.

How to check if a string is numeric?

You can use Character.isDigit(char ch) method or you can also use regular expression.

Below is the snippet:

public class CheckDigit {

private static Scanner input;

public static void main(String[] args) {

    System.out.print("Enter a String:");
    input = new Scanner(System.in);
    String str = input.nextLine();

    if (CheckString(str)) {
        System.out.println(str + " is numeric");
    } else {
        System.out.println(str +" is not numeric");
    }
}

public static boolean CheckString(String str) {
    for (char c : str.toCharArray()) {
        if (!Character.isDigit(c))
            return false;
    }
    return true;
}

}

plotting different colors in matplotlib

Joe Kington's excellent answer is already 4 years old, Matplotlib has incrementally changed (in particular, the introduction of the cycler module) and the new major release, Matplotlib 2.0.x, has introduced stylistic differences that are important from the point of view of the colors used by default.

The color of individual lines

The color of individual lines (as well as the color of different plot elements, e.g., markers in scatter plots) is controlled by the color keyword argument,

plt.plot(x, y, color=my_color)

my_color is either

The color cycle

By default, different lines are plotted using different colors, that are defined by default and are used in a cyclic manner (hence the name color cycle).

The color cycle is a property of the axes object, and in older releases was simply a sequence of valid color names (by default a string of one character color names, "bgrcmyk") and you could set it as in

my_ax.set_color_cycle(['kbkykrkg'])

(as noted in a comment this API has been deprecated, more on this later).

In Matplotlib 2.0 the default color cycle is ["#1f77b4", "#ff7f0e", "#2ca02c", "#d62728", "#9467bd", "#8c564b", "#e377c2", "#7f7f7f", "#bcbd22", "#17becf"], the Vega category10 palette.

enter image description here

(the image is a screenshot from https://vega.github.io/vega/docs/schemes/)

The cycler module: composable cycles

The following code shows that the color cycle notion has been deprecated

In [1]: from matplotlib import rc_params

In [2]: rc_params()['axes.color_cycle']
/home/boffi/lib/miniconda3/lib/python3.6/site-packages/matplotlib/__init__.py:938: UserWarning: axes.color_cycle is deprecated and replaced with axes.prop_cycle; please use the latter.
  warnings.warn(self.msg_depr % (key, alt_key))
Out[2]: 
['#1f77b4', '#ff7f0e', '#2ca02c', '#d62728', '#9467bd',
 '#8c564b', '#e377c2', '#7f7f7f', '#bcbd22', '#17becf']

Now the relevant property is the 'axes.prop_cycle'

In [3]: rc_params()['axes.prop_cycle']
Out[3]: cycler('color', ['#1f77b4', '#ff7f0e', '#2ca02c', '#d62728', '#9467bd', '#8c564b', '#e377c2', '#7f7f7f', '#bcbd22', '#17becf'])

Previously, the color_cycle was a generic sequence of valid color denominations, now by default it is a cycler object containing a label ('color') and a sequence of valid color denominations. The step forward with respect to the previous interface is that it is possible to cycle not only on the color of lines but also on other line attributes, e.g.,

In [5]: from cycler import cycler

In [6]: new_prop_cycle = cycler('color', ['k', 'r']) * cycler('linewidth', [1., 1.5, 2.])

In [7]: for kwargs in new_prop_cycle: print(kwargs)
{'color': 'k', 'linewidth': 1.0}
{'color': 'k', 'linewidth': 1.5}
{'color': 'k', 'linewidth': 2.0}
{'color': 'r', 'linewidth': 1.0}
{'color': 'r', 'linewidth': 1.5}
{'color': 'r', 'linewidth': 2.0}

As you have seen, the cycler objects are composable and when you iterate on a composed cycler what you get, at each iteration, is a dictionary of keyword arguments for plt.plot.

You can use the new defaults on a per axes object ratio,

my_ax.set_prop_cycle(new_prop_cycle)

or you can install temporarily the new default

plt.rc('axes', prop_cycle=new_prop_cycle)

or change altogether the default editing your .matplotlibrc file.

Last possibility, use a context manager

with plt.rc_context({'axes.prop_cycle': new_prop_cycle}):
    ...

to have the new cycler used in a group of different plots, reverting to defaults at the end of the context.

The doc string of the cycler() function is useful, but the (not so much) gory details about the cycler module and the cycler() function, as well as examples, can be found in the fine docs.

Python: Passing variables between functions

This is what is actually happening:

global_list = []

def defineAList():
    local_list = ['1','2','3']
    print "For checking purposes: in defineAList, list is", local_list 
    return local_list 

def useTheList(passed_list):
    print "For checking purposes: in useTheList, list is", passed_list

def main():
    # returned list is ignored
    returned_list = defineAList()   

    # passed_list inside useTheList is set to global_list
    useTheList(global_list) 

main()

This is what you want:

def defineAList():
    local_list = ['1','2','3']
    print "For checking purposes: in defineAList, list is", local_list 
    return local_list 

def useTheList(passed_list):
    print "For checking purposes: in useTheList, list is", passed_list

def main():
    # returned list is ignored
    returned_list = defineAList()   

    # passed_list inside useTheList is set to what is returned from defineAList
    useTheList(returned_list) 

main()

You can even skip the temporary returned_list and pass the returned value directly to useTheList:

def main():
    # passed_list inside useTheList is set to what is returned from defineAList
    useTheList(defineAList()) 

Object array initialization without default constructor

You can always create an array of pointers , pointing to car objects and then create objects, in a for loop, as you want and save their address in the array , for example :

#include <iostream>
class Car
{
private:
  Car(){};
  int _no;
public:
  Car(int no)
  {
    _no=no;
  }
  void printNo()
  {
    std::cout<<_no<<std::endl;
  }
};
void printCarNumbers(Car *cars, int length)
{
    for(int i = 0; i<length;i++)
         std::cout<<cars[i].printNo();
}

int main()
{
  int userInput = 10;
  Car **mycars = new Car*[userInput];
  int i;
  for(i=0;i<userInput;i++)
      mycars[i] = new Car(i+1);

note new method !!!

  printCarNumbers_new(mycars,userInput);


  return 0;
}    

All you have to change in new method is handling cars as pointers than static objects in parameter and when calling method printNo() for example :

void printCarNumbers_new(Car **cars, int length)
{
    for(int i = 0; i<length;i++)
         std::cout<<cars[i]->printNo();
}

at the end of main is good to delete all dynamicly allocated memory like this

for(i=0;i<userInput;i++)
  delete mycars[i];      //deleting one obgject
delete[] mycars;         //deleting array of objects

Hope I helped, cheers!

Truncate/round whole number in JavaScript?

I'll add my solution here. We can use floor when values are above 0 and ceil when they are less than zero:

function truncateToInt(x)
{
    if(x > 0)
    {
         return Math.floor(x);
    }
    else
    {
         return Math.ceil(x);
    }
 }

Then:

y = truncateToInt(2.9999); // results in 2
y = truncateToInt(-3.118); //results in -3

Notice: This answer was written when Math.trunc(x) was fairly new and not supported by a lot of browsers. Today, modern browsers support Math.trunc(x).

How can I ssh directly to a particular directory?

I've created a tool to SSH and CD into a server consecutively – aptly named sshcd. For the example you've given, you'd simply use:

sshcd somehost:/some/directory/somewhere/named/Foo

Let me know if you have any questions or problems!

Recommended way to get hostname in Java

InetAddress.getLocalHost().getHostName() is the best way out of the two as this is the best abstraction at the developer level.

Query to convert from datetime to date mysql

Use the DATE function:

SELECT DATE(orders.date_purchased) AS date

How to tell 'PowerShell' Copy-Item to unconditionally copy files

From the documentation (help copy-item -full):

-force <SwitchParameter>
    Allows cmdlet to override restrictions such as renaming existing files as long as security is not compromised.

    Required?                    false
    Position?                    named
    Default value                False
    Accept pipeline input?       false
    Accept wildcard characters?  false

ScrollTo function in AngularJS

Another suggestion. One directive with selector.

HTML:

<button type="button" scroll-to="#catalogSection">Scroll To</button>

Angular:

app.directive('scrollTo', function () {
    return {
        restrict: 'A',
        link: function (scope, element, attrs) {
            element.on('click', function () {

                var target = $(attrs.scrollTo);
                if (target.length > 0) {
                    $('html, body').animate({
                        scrollTop: target.offset().top
                    });
                }
            });
        }
    }
});

Also notice $anchorScroll

Best way to parse command-line parameters?

How to parse parameters without an external dependency. Great question! You may be interested in picocli.

Picocli is specifically designed to solve the problem asked in the question: it is a command line parsing framework in a single file, so you can include it in source form. This lets users run picocli-based applications without requiring picocli as an external dependency.

It works by annotating fields so you write very little code. Quick summary:

  • Strongly typed everything - command line options as well as positional parameters
  • Support for POSIX clustered short options (so it handles <command> -xvfInputFile as well as <command> -x -v -f InputFile)
  • An arity model that allows a minimum, maximum and variable number of parameters, e.g, "1..*", "3..5"
  • Fluent and compact API to minimize boilerplate client code
  • Subcommands
  • Usage help with ANSI colors

The usage help message is easy to customize with annotations (without programming). For example:

Extended usage help message (source)

I couldn't resist adding one more screenshot to show what kind of usage help messages are possible. Usage help is the face of your application, so be creative and have fun!

picocli demo

Disclaimer: I created picocli. Feedback or questions very welcome. It is written in java, but let me know if there is any issue using it in scala and I'll try to address it.

Java 8 Distinct by property

Extending Stuart Marks's answer, this can be done in a shorter way and without a concurrent map (if you don't need parallel streams):

public static <T> Predicate<T> distinctByKey(Function<? super T, ?> keyExtractor) {
    final Set<Object> seen = new HashSet<>();
    return t -> seen.add(keyExtractor.apply(t));
}

Then call:

persons.stream().filter(distinctByKey(p -> p.getName());

How to import a new font into a project - Angular 5

You can try creating a css for your font with font-face (like explained here)

Step #1

Create a css file with font face and place it somewhere, like in assets/fonts

customfont.css

@font-face {
    font-family: YourFontFamily;
    src: url("/assets/font/yourFont.otf") format("truetype");
}

Step #2

Add the css to your .angular-cli.json in the styles config

"styles":[
 //...your other styles
 "assets/fonts/customFonts.css"
 ]

Do not forget to restart ng serve after doing this

Step #3

Use the font in your code

component.css

span {font-family: YourFontFamily; }

How can I add a .npmrc file?

This issue is because of you having some local or private packages. For accessing those packages you have to create .npmrc file for this issue. Just refer the following link for your solution. https://nodesource.com/blog/configuring-your-npmrc-for-an-optimal-node-js-environment

jQuery slide left and show

You can add new function to your jQuery library by adding these line on your own script file and you can easily use fadeSlideRight() and fadeSlideLeft().

Note: you can change width of animation as you like instance of 750px.

$.fn.fadeSlideRight = function(speed,fn) {
    return $(this).animate({
        'opacity' : 1,
        'width' : '750px'
    },speed || 400, function() {
        $.isFunction(fn) && fn.call(this);
    });
}

$.fn.fadeSlideLeft = function(speed,fn) {
    return $(this).animate({
        'opacity' : 0,
        'width' : '0px'
    },speed || 400,function() {
        $.isFunction(fn) && fn.call(this);
    });
}

How to check if MySQL returns null/empty?

select FOUND_ROWS();

will return no. of records selected by select query.

multiple where condition codeigniter

you can use both use array like :

$array = array('tlb_account.crid' =>$value , 'tlb_request.sign'=> 'FALSE' );

and direct assign like:

$this->db->where('tlb_account.crid' =>$value , 'tlb_request.sign'=> 'FALSE');

I wish help you.

jQuery - Click event on <tr> elements with in a table and getting <td> element values

<script>
jQuery(document).ready(function() {
    jQuery("tr").click(function(){
       alert("Click! "+ jQuery(this).find('td').html());
    });
});
</script>

Creating a list/array in excel using VBA to get a list of unique names in a column

You don't need arrays for this. Try something like:

ActiveSheet.Range("$A$1:$A$" & LastRow).RemoveDuplicates Columns:=1, Header:=xlYes

If there's no header, change accordingly.

EDIT: Here's the traditional method, which takes advantage of the fact that each item in a Collection must have a unique key:

Sub test()
Dim ws As Excel.Worksheet
Dim LastRow As Long
Dim coll As Collection
Dim cell As Excel.Range
Dim arr() As String
Dim i As Long

Set ws = ActiveSheet
With ws
    LastRow = .Range("C" & .Rows.Count).End(xlUp).Row
    Set coll = New Collection
    For Each cell In .Range("C4:C" & LastRow)
        On Error Resume Next
        coll.Add cell.Value, CStr(cell.Value)
        On Error GoTo 0
    Next cell
    ReDim arr(1 To coll.Count)
    For i = LBound(arr) To UBound(arr)
        arr(i) = coll(i)
        'to show in Immediate Window
        Debug.Print arr(i)
    Next i
End With
End Sub

Index was out of range. Must be non-negative and less than the size of the collection parameter name:index

what this means ? is there any problem in my code

It means that you are accessing a location or index which is not present in collection.

To find this, Make sure your Gridview has 5 columns as you are using it's 5th column by this line

dataGridView1.Columns[4].Name = "Amount";

Here is the image which shows the elements of an array. So if your gridview has less column then the (index + 1) by which you are accessing it, then this exception arises.

enter image description here

JavaScript listener, "keypress" doesn't detect backspace?

Try keydown instead of keypress.

The keyboard events occur in this order: keydown, keyup, keypress

The problem with backspace probably is, that the browser will navigate back on keyup and thus your page will not see the keypress event.

List all files in one directory PHP

Check this out : readdir()

This bit of code should list all entries in a certain directory:

if ($handle = opendir('.')) {

    while (false !== ($entry = readdir($handle))) {

        if ($entry != "." && $entry != "..") {

            echo "$entry\n";
        }
    }

    closedir($handle);
}

Edit: miah's solution is much more elegant than mine, you should use his solution instead.

Button Listener for button in fragment in android

Try this :

FragmentOne.java

import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;

public class FragmentOne extends Fragment{

    View rootView;        

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

        rootView = inflater.inflate(R.layout.fragment_one, container, false);


        Button button = (Button) rootView.findViewById(R.id.buttonSayHi);
        button.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View v)
            {
                onButtonClicked(v);
            }
        });
        return rootView;
    }

  public void onButtonClicked(View view)
  {
          //do your stuff here..           
    final FragmentTransaction ft = getFragmentManager().beginTransaction(); 
    ft.replace(R.id.frameLayoutFragmentContainer, new FragmentTwo(), "NewFragmentTag"); 
    ft.commit(); 

    ft.addToBackStack(null);    
  }
}

check this : click here

The backend version is not supported to design database diagrams or tables

You only get that message if you try to use Designer or diagrams. If you use t-SQL it works fine:

Select * 

into newdb.dbo.newtable
from olddb.dbo.yourtable

where olddb.dbo.yourtable has been created in 2008 exactly as you want the table to be in 2012

Detect when an image fails to load in Javascript

You could try the following code. I can't vouch for browser compatibility though, so you'll have to test that.

function testImage(URL) {
    var tester=new Image();
    tester.onload=imageFound;
    tester.onerror=imageNotFound;
    tester.src=URL;
}

function imageFound() {
    alert('That image is found and loaded');
}

function imageNotFound() {
    alert('That image was not found.');
}

testImage("http://foo.com/bar.jpg");

And my sympathies for the jQuery-resistant boss!

Convert Mongoose docs to json

I found out I made a mistake. There's no need to call toObject() or toJSON() at all. The __proto__ in the question came from jquery, not mongoose. Here's my test:

UserModel.find({}, function (err, users) {
    console.log(users.save);    // { [Function] numAsyncPres: 0 }
    var json = JSON.stringify(users);
    users = users.map(function (user) {
        return user.toObject();
    }
    console.log(user.save);    // undefined
    console.log(json == JSON.stringify(users));    // true
}

doc.toObject() removes doc.prototype from a doc. But it makes no difference in JSON.stringify(doc). And it's not needed in this case.

FormData.append("key", "value") is not working

New in Chrome 50+ and Firefox 39+ (resp. 44+):

  • formdata.entries() (combine with Array.from() for debugability)
  • formdata.get(key)
  • and more very useful methods

Original answer:

What I usually do to 'debug' a FormData object, is just send it (anywhere!) and check the browser logs (eg. Chrome devtools' Network tab).

You don't need a/the same Ajax framework. You don't need any details. Just send it:

var xhr = new XMLHttpRequest;
xhr.open('POST', '/', true);
xhr.send(data);

Easy.

How to create composite primary key in SQL Server 2008

I know I'm late to this party, but for an existing table, try:

ALTER table TABLE_NAME
ADD CONSTRAINT [name of your PK, e.g. PK_TableName] PRIMARY KEY CLUSTERED (column1, column2, etc.)

Why can't C# interfaces contain fields?

A lot has been said already, but to make it simple, here's my take. Interfaces are intended to have method contracts to be implemented by the consumers or classes and not to have fields to store values.

You may argue that then why properties are allowed? So the simple answer is - properties are internally defined as methods only.

Why am I getting an error "Object literal may only specify known properties"?

As of TypeScript 1.6, properties in object literals that do not have a corresponding property in the type they're being assigned to are flagged as errors.

Usually this error means you have a bug (typically a typo) in your code, or in the definition file. The right fix in this case would be to fix the typo. In the question, the property callbackOnLoactionHash is incorrect and should have been callbackOnLocationHash (note the mis-spelling of "Location").

This change also required some updates in definition files, so you should get the latest version of the .d.ts for any libraries you're using.

Example:

interface TextOptions {
    alignment?: string;
    color?: string;
    padding?: number;
}
function drawText(opts: TextOptions) { ... }
drawText({ align: 'center' }); // Error, no property 'align' in 'TextOptions'

But I meant to do that

There are a few cases where you may have intended to have extra properties in your object. Depending on what you're doing, there are several appropriate fixes

Type-checking only some properties

Sometimes you want to make sure a few things are present and of the correct type, but intend to have extra properties for whatever reason. Type assertions (<T>v or v as T) do not check for extra properties, so you can use them in place of a type annotation:

interface Options {
    x?: string;
    y?: number;
}

// Error, no property 'z' in 'Options'
let q1: Options = { x: 'foo', y: 32, z: 100 };
// OK
let q2 = { x: 'foo', y: 32, z: 100 } as Options;
// Still an error (good):
let q3 = { x: 100, y: 32, z: 100 } as Options;

These properties and maybe more

Some APIs take an object and dynamically iterate over its keys, but have 'special' keys that need to be of a certain type. Adding a string indexer to the type will disable extra property checking

Before

interface Model {
  name: string;
}
function createModel(x: Model) { ... }

// Error
createModel({name: 'hello', length: 100});

After

interface Model {
  name: string;
  [others: string]: any;
}
function createModel(x: Model) { ... }

// OK
createModel({name: 'hello', length: 100});

This is a dog or a cat or a horse, not sure yet

interface Animal { move; }
interface Dog extends Animal { woof; }
interface Cat extends Animal { meow; }
interface Horse extends Animal { neigh; }

let x: Animal;
if(...) {
  x = { move: 'doggy paddle', woof: 'bark' };
} else if(...) {
  x = { move: 'catwalk', meow: 'mrar' };
} else {
  x = { move: 'gallop', neigh: 'wilbur' };
}

Two good solutions come to mind here

Specify a closed set for x

// Removes all errors
let x: Dog|Cat|Horse;

or Type assert each thing

// For each initialization
  x = { move: 'doggy paddle', woof: 'bark' } as Dog;

This type is sometimes open and sometimes not

A clean solution to the "data model" problem using intersection types:

interface DataModelOptions {
  name?: string;
  id?: number;
}
interface UserProperties {
  [key: string]: any;
}
function createDataModel(model: DataModelOptions & UserProperties) {
 /* ... */
}
// findDataModel can only look up by name or id
function findDataModel(model: DataModelOptions) {
 /* ... */
}
// OK
createDataModel({name: 'my model', favoriteAnimal: 'cat' });
// Error, 'ID' is not correct (should be 'id')
findDataModel({ ID: 32 });

See also https://github.com/Microsoft/TypeScript/issues/3755

Find a value in an array of objects in Javascript

You can use query-objects from npm. You can search an array of objects using filters.

const queryable = require('query-objects');

const users = [
    {
      firstName: 'George',
      lastName: 'Eracleous',
      age: 28
    },
    {
      firstName: 'Erica',
      lastName: 'Archer',
      age: 50
    },
    {
      firstName: 'Leo',
      lastName: 'Andrews',
      age: 20
    }
];

const filters = [
    {
      field: 'age',
      value: 30,
      operator: 'lt'
    },
    {
      field: 'firstName',
      value: 'Erica',
      operator: 'equals'
    }
];

// Filter all users that are less than 30 years old AND their first name is Erica
const res = queryable(users).and(filters);

// Filter all users that are less than 30 years old OR their first name is Erica
const res = queryable(users).or(filters);

java create date object using a value string

try this, it worked for me.

 String inputString = "01-01-1900";
    Date inputDate= null;
    try {
        inputDate = new SimpleDateFormat("dd-MM-yyyy").parse(inputString);
    } catch (ParseException e) {
        e.printStackTrace();
    }

    dp.getDatePicker().setMinDate(inputDate.getTime());

Printing leading 0's in C

ZIP Code is a highly localised field, and many countries have characters in their postcodes, e.g., UK, Canada. Therefore, in this example, you should use a string / varchar field to store it if at any point you would be shipping or getting users, customers, clients, etc. from other countries.

However, in the general case, you should use the recommended answer (printf("%05d", number);).

getElementsByClassName not working

If you want to do it by ClassName you could do:

<script type="text/javascript">
function hideTd(className){
    var elements;

    if (document.getElementsByClassName)
    {
        elements = document.getElementsByClassName(className);
    }
    else
    {
        var elArray = [];
        var tmp = document.getElementsByTagName(elements);  
        var regex = new RegExp("(^|\\s)" + className+ "(\\s|$)");
        for ( var i = 0; i < tmp.length; i++ ) {

            if ( regex.test(tmp[i].className) ) {
                elArray.push(tmp[i]);
            }
        }

        elements = elArray;
    }

    for(var i = 0, i < elements.length; i++) {
       if( elements[i].textContent == ''){
          elements[i].style.display = 'none';
       } 
    }

  }
</script>

How to use a variable inside a regular expression?

You can use format keyword as well for this.Format method will replace {} placeholder to the variable which you passed to the format method as an argument.

if re.search(r"\b(?=\w)**{}**\b(?!\w)".**format(TEXTO)**, subject, re.IGNORECASE):
    # Successful match**strong text**
else:
    # Match attempt failed

Disable Input fields in reactive form

name: [{value: '', disabled: true}, Validators.required],
name: [{value: '', disabled: this.isDisabled}, Validators.required],

or

this.form.controls['name'].disable();

Pass in an enum as a method parameter

If you want to pass in the value to use, you have to use the enum type you declared and directly use the supplied value:

public string CreateFile(string id, string name, string description,
              /* --> */  SupportedPermissions supportedPermissions)
{
    file = new File
    {  
        Name = name,
        Id = id,
        Description = description,
        SupportedPermissions = supportedPermissions // <---
    };

    return file.Id;
}

If you instead want to use a fixed value, you don't need any parameter at all. Instead, directly use the enum value. The syntax is similar to a static member of a class:

public string CreateFile(string id, string name, string description) // <---
{
    file = new File
    {  
        Name = name,
        Id = id,
        Description = description,
        SupportedPermissions = SupportedPermissions.basic // <---
    };

    return file.Id;
}

What is PAGEIOLATCH_SH wait type in SQL Server?

From Microsoft documentation:

PAGEIOLATCH_SH

Occurs when a task is waiting on a latch for a buffer that is in an I/O request. The latch request is in Shared mode. Long waits may indicate problems with the disk subsystem.

In practice, this almost always happens due to large scans over big tables. It almost never happens in queries that use indexes efficiently.

If your query is like this:

Select * from <table> where <col1> = <value> order by <PrimaryKey>

, check that you have a composite index on (col1, col_primary_key).

If you don't have one, then you'll need either a full INDEX SCAN if the PRIMARY KEY is chosen, or a SORT if an index on col1 is chosen.

Both of them are very disk I/O consuming operations on large tables.

How do I display images from Google Drive on a website?

If you have some image files, just upload them to a public folder on your Google Drive, copy its folder ID from the address bar (e.g. 0B0Gi4v5omoZUVXhCT2kta1l0ZG8) and paste it into a form at GDrives, then choose your own alias (e.g. myimgs) and voila! You can access the images one by one using e.g. http://gdriv.es/myimgs/myimage.jpg.

If you want to embed a whole folder on your website (in a frame), you can use one of the following URLs, replacing [folderID] with your own ID:

If you prefer to get the file list in XML or JSON, you can use YQL.

Note: You can use Google+ Photos to host ans embed your images as well.

Display animated GIF in iOS

Another alternative is to use a UIWebView to display the animated GIF. If the GIF is going to be fetched from a server, then this takes care of the fetching. It also works with local GIFs.

How to filter a data frame

You are missing a comma in your statement.

Try this:

data[data[, "Var1"]>10, ]

Or:

data[data$Var1>10, ]

Or:

subset(data, Var1>10)

As an example, try it on the built-in dataset, mtcars

data(mtcars)

mtcars[mtcars[, "mpg"]>25, ]

                mpg cyl  disp  hp drat    wt  qsec vs am gear carb
Fiat 128       32.4   4  78.7  66 4.08 2.200 19.47  1  1    4    1
Honda Civic    30.4   4  75.7  52 4.93 1.615 18.52  1  1    4    2
Toyota Corolla 33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1
Fiat X1-9      27.3   4  79.0  66 4.08 1.935 18.90  1  1    4    1
Porsche 914-2  26.0   4 120.3  91 4.43 2.140 16.70  0  1    5    2
Lotus Europa   30.4   4  95.1 113 3.77 1.513 16.90  1  1    5    2


mtcars[mtcars$mpg>25, ]

                mpg cyl  disp  hp drat    wt  qsec vs am gear carb
Fiat 128       32.4   4  78.7  66 4.08 2.200 19.47  1  1    4    1
Honda Civic    30.4   4  75.7  52 4.93 1.615 18.52  1  1    4    2
Toyota Corolla 33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1
Fiat X1-9      27.3   4  79.0  66 4.08 1.935 18.90  1  1    4    1
Porsche 914-2  26.0   4 120.3  91 4.43 2.140 16.70  0  1    5    2
Lotus Europa   30.4   4  95.1 113 3.77 1.513 16.90  1  1    5    2

subset(mtcars, mpg>25)

                mpg cyl  disp  hp drat    wt  qsec vs am gear carb
Fiat 128       32.4   4  78.7  66 4.08 2.200 19.47  1  1    4    1
Honda Civic    30.4   4  75.7  52 4.93 1.615 18.52  1  1    4    2
Toyota Corolla 33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1
Fiat X1-9      27.3   4  79.0  66 4.08 1.935 18.90  1  1    4    1
Porsche 914-2  26.0   4 120.3  91 4.43 2.140 16.70  0  1    5    2
Lotus Europa   30.4   4  95.1 113 3.77 1.513 16.90  1  1    5    2

MySQL - How to select rows where value is in array?

If the array element is not integer you can use something like below :

$skus  = array('LDRES10','LDRES12','LDRES11');   //sample data

if(!empty($skus)){     
    $sql = "SELECT * FROM `products` WHERE `prodCode` IN ('" . implode("','", $skus) . "') "      
}

Async/Await Class Constructor

This can never work.

The async keyword allows await to be used in a function marked as async but it also converts that function into a promise generator. So a function marked with async will return a promise. A constructor on the other hand returns the object it is constructing. Thus we have a situation where you want to both return an object and a promise: an impossible situation.

You can only use async/await where you can use promises because they are essentially syntax sugar for promises. You can't use promises in a constructor because a constructor must return the object to be constructed, not a promise.

There are two design patterns to overcome this, both invented before promises were around.

  1. Use of an init() function. This works a bit like jQuery's .ready(). The object you create can only be used inside it's own init or ready function:

    Usage:

    var myObj = new myClass();
    myObj.init(function() {
        // inside here you can use myObj
    });
    

    Implementation:

    class myClass {
        constructor () {
    
        }
    
        init (callback) {
            // do something async and call the callback:
            callback.bind(this)();
        }
    }
    
  2. Use a builder. I've not seen this used much in javascript but this is one of the more common work-arounds in Java when an object needs to be constructed asynchronously. Of course, the builder pattern is used when constructing an object that requires a lot of complicated parameters. Which is exactly the use-case for asynchronous builders. The difference is that an async builder does not return an object but a promise of that object:

    Usage:

    myClass.build().then(function(myObj) {
        // myObj is returned by the promise, 
        // not by the constructor
        // or builder
    });
    
    // with async/await:
    
    async function foo () {
        var myObj = await myClass.build();
    }
    

    Implementation:

    class myClass {
        constructor (async_param) {
            if (typeof async_param === 'undefined') {
                throw new Error('Cannot be called directly');
            }
        }
    
        static build () {
            return doSomeAsyncStuff()
               .then(function(async_result){
                   return new myClass(async_result);
               });
        }
    }
    

    Implementation with async/await:

    class myClass {
        constructor (async_param) {
            if (typeof async_param === 'undefined') {
                throw new Error('Cannot be called directly');
            }
        }
    
        static async build () {
            var async_result = await doSomeAsyncStuff();
            return new myClass(async_result);
        }
    }
    

Note: although in the examples above we use promises for the async builder they are not strictly speaking necessary. You can just as easily write a builder that accept a callback.


Note on calling functions inside static functions.

This has nothing whatsoever to do with async constructors but with what the keyword this actually mean (which may be a bit surprising to people coming from languages that do auto-resolution of method names, that is, languages that don't need the this keyword).

The this keyword refers to the instantiated object. Not the class. Therefore you cannot normally use this inside static functions since the static function is not bound to any object but is bound directly to the class.

That is to say, in the following code:

class A {
    static foo () {}
}

You cannot do:

var a = new A();
a.foo() // NOPE!!

instead you need to call it as:

A.foo();

Therefore, the following code would result in an error:

class A {
    static foo () {
        this.bar(); // you are calling this as static
                    // so bar is undefinned
    }
    bar () {}
}

To fix it you can make bar either a regular function or a static method:

function bar1 () {}

class A {
    static foo () {
        bar1();   // this is OK
        A.bar2(); // this is OK
    }

    static bar2 () {}
}

Bash loop ping successful

Here's my one-liner solution:

screen -S internet-check -d -m -- bash -c 'while ! ping -c 1 google.com; do echo -; done; echo Google responding to ping | mail -s internet-back [email protected]'

This runs an infinite ping in a new screen session until there is a response, at which point it sends an e-mail to [email protected]. Useful in the age of e-mail sent to phones.

(You might want to check that mail is configured correctly by just running echo test | mail -s test [email protected] first. Of course you can do whatever you want from done; onwards, sound a bell, start a web browser, use your imagination.)

Using FileUtils in eclipse

<!-- https://mvnrepository.com/artifact/org.apache.directory.studio/org.apache.commons.io -->
<dependency>
    <groupId>org.apache.directory.studio</groupId>
    <artifactId>org.apache.commons.io</artifactId>
    <version>2.4</version>
</dependency>

Add above dependency in pom.xml file

How to add an extra source directory for maven to compile and include in the build jar?

You can use the Build Helper Plugin, e.g:

<project>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>build-helper-maven-plugin</artifactId>
        <version>3.2.0</version>
        <executions>
          <execution>
            <id>add-source</id>
            <phase>generate-sources</phase>
            <goals>
              <goal>add-source</goal>
            </goals>
            <configuration>
              <sources>
                <source>some directory</source>
                ...
              </sources>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
</project>

How to get the month name in C#?

Supposing your date is today. Hope this helps you.

DateTime dt = DateTime.Today;

string thisMonth= dt.ToString("MMMM");

Console.WriteLine(thisMonth);

HTTP Status 500 - Servlet.init() for servlet Dispatcher threw exception

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>teste4</groupId>
    <artifactId>teste4</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>

    <repositories>
        <repository>
            <id>prime-repo</id>
            <name>PrimeFaces Maven Repository</name>
            <url>http://repository.primefaces.org</url>
            <layout>default</layout>
        </repository>
    </repositories>



    <dependencies>
        <dependency>
            <groupId>com.sun.faces</groupId>
            <artifactId>jsf-impl</artifactId>
            <version>2.2.4</version>
        </dependency>


        <dependency>
            <groupId>com.sun.faces</groupId>
            <artifactId>jsf-api</artifactId>
            <version>2.2.4</version>
        </dependency>



        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>
        <dependency>
            <groupId>org.primefaces</groupId>
            <artifactId>primefaces</artifactId>
            <version>4.0</version>
        </dependency>
        <dependency>
            <groupId>org.primefaces.themes</groupId>
            <artifactId>bootstrap</artifactId>
            <version>1.0.9</version>
        </dependency>
        <dependency>
            <groupId>commons-fileupload</groupId>
            <artifactId>commons-fileupload</artifactId>
            <version>1.3</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.27</version>
        </dependency>

        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>4.2.7.Final</version>
        </dependency>

    </dependencies>


</project>

Jackson with JSON: Unrecognized field, not marked as ignorable

I fixed this problem by simply changing the signatures of my setter and getter methods of my POJO class. All I had to do was change the getObject method to match what the mapper was looking for. In my case I had a getImageUrl originally, but the JSON data had image_url which was throwing the mapper off. I changed both my setter and getters to getImage_url and setImage_url.

Hope this helps.

Obtain smallest value from array in Javascript?

_x000D_
_x000D_
function smallest(){_x000D_
  if(arguments[0] instanceof Array)_x000D_
    arguments = arguments[0];_x000D_
_x000D_
  return Math.min.apply( Math, arguments );_x000D_
}_x000D_
function largest(){_x000D_
  if(arguments[0] instanceof Array)_x000D_
    arguments = arguments[0];_x000D_
_x000D_
  return Math.max.apply( Math, arguments );_x000D_
}_x000D_
var min = smallest(10, 11, 12, 13);_x000D_
var max = largest([10, 11, 12, 13]);_x000D_
_x000D_
console.log("Smallest: "+ min +", Largest: "+ max);
_x000D_
_x000D_
_x000D_

How to change port number in vue-cli project

Best way is to update the serve script command in your package.json file. Just append --port 3000 like so:

"scripts": {
  "serve": "vue-cli-service serve --port 3000",
  "build": "vue-cli-service build",
  "inspect": "vue-cli-service inspect",
  "lint": "vue-cli-service lint"
},

How to download a file via FTP with Python ftplib

A = filename

ftp = ftplib.FTP("IP")
ftp.login("USR Name", "Pass")
ftp.cwd("/Dir")


try:
    ftp.retrbinary("RETR " + filename ,open(A, 'wb').write)
except:
    print "Error"

Removing elements from an array in C

Try this simple code:

#include <stdio.h>
#include <conio.h>
void main(void)
{ 
    clrscr();
    int a[4], i, b;
    printf("enter nos ");
    for (i = 1; i <= 5; i++) {
        scanf("%d", &a[i]);
    }
    for(i = 1; i <= 5; i++) {
        printf("\n%d", a[i]);
    }
    printf("\nenter element you want to delete ");
    scanf("%d", &b);
    for (i = 1; i <= 5; i++) {
        if(i == b) {
            a[i] = i++;
        }
        printf("\n%d", a[i]);
    }
    getch();
}

Get selected value of a dropdown's item using jQuery

I know this is old but I though I update this with an more up to date answer

$( document ).on( 'change', '#combo', function () {
var prepMin= $("#combo option:selected").val();
 alert(prepMin);
});

I hope this helps

Character reading from file in Python

Ref: http://docs.python.org/howto/unicode

Reading Unicode from a file is therefore simple:

import codecs
with codecs.open('unicode.rst', encoding='utf-8') as f:
    for line in f:
        print repr(line)

It's also possible to open files in update mode, allowing both reading and writing:

with codecs.open('test', encoding='utf-8', mode='w+') as f:
    f.write(u'\u4500 blah blah blah\n')
    f.seek(0)
    print repr(f.readline()[:1])

EDIT: I'm assuming that your intended goal is just to be able to read the file properly into a string in Python. If you're trying to convert to an ASCII string from Unicode, then there's really no direct way to do so, since the Unicode characters won't necessarily exist in ASCII.

If you're trying to convert to an ASCII string, try one of the following:

  1. Replace the specific unicode chars with ASCII equivalents, if you are only looking to handle a few special cases such as this particular example

  2. Use the unicodedata module's normalize() and the string.encode() method to convert as best you can to the next closest ASCII equivalent (Ref https://web.archive.org/web/20090228203858/http://techxplorer.com/2006/07/18/converting-unicode-to-ascii-using-python):

    >>> teststr
    u'I don\xe2\x80\x98t like this'
    >>> unicodedata.normalize('NFKD', teststr).encode('ascii', 'ignore')
    'I donat like this'
    

How do you make a div tag into a link

<div style="cursor:pointer" onclick="document.location='http://www.google.com'">Content Goes Here</div>

What is the difference between Step Into and Step Over in a debugger

step into will dig into method calls
step over will just execute the line and go to the next one

Is it possible to create a temporary table in a View and drop it after select?

You can achieve what you are trying to do, using a Stored Procedure which returns a query result. Views are not suitable / developed for operations like this one.

Good tutorial for using HTML5 History API (Pushstate?)

Here is a great screen-cast on the topic by Ryan Bates of railscasts. At the end he simply disables the ajax functionality if the history.pushState method is not available:

http://railscasts.com/episodes/246-ajax-history-state

Reading a UTF8 CSV file with Python

The link to the help page is the same for python 2.6 and as far as I know there was no change in the csv module since 2.5 (besides bug fixes). Here is the code that just works without any encoding/decoding (file da.csv contains the same data as the variable data). I assume that your file should be read correctly without any conversions.

test.py:

## -*- coding: utf-8 -*-
#
# NOTE: this first line is important for the version b) read from a string(unicode) variable
#

import csv

data = \
"""0665000FS10120684,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Bleu
0665000FS10120689,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Gris
0665000FS10120687,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Vert"""

# a) read from a file
print 'reading from a file:'
for (f1, f2, f3) in csv.reader(open('da.csv'), dialect=csv.excel):
    print (f1, f2, f3)

# b) read from a string(unicode) variable
print 'reading from a list of strings:'
reader = csv.reader(data.split('\n'), dialect=csv.excel)
for (f1, f2, f3) in reader:
    print (f1, f2, f3)

da.csv:

0665000FS10120684,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Bleu
0665000FS10120689,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Gris
0665000FS10120687,SD1200IS,Appareil photo numérique PowerShot de 10 Mpx de Canon avec trépied (SD1200IS) - Vert

gcc: undefined reference to

However, avpicture_get_size is defined.

No, as the header (<libavcodec/avcodec.h>) just declares it.

The definition is in the library itself.

So you might like to add the linker option to link libavcodec when invoking gcc:

-lavcodec

Please also note that libraries need to be specified on the command line after the files needing them:

gcc -I$HOME/ffmpeg/include program.c -lavcodec

Not like this:

gcc -lavcodec -I$HOME/ffmpeg/include program.c

Referring to Wyzard's comment, the complete command might look like this:

gcc -I$HOME/ffmpeg/include program.c -L$HOME/ffmpeg/lib -lavcodec

For libraries not stored in the linkers standard location the option -L specifies an additional search path to lookup libraries specified using the -l option, that is libavcodec.x.y.z in this case.


For a detailed reference on GCC's linker option, please read here.

Getting list of items inside div using Selenium Webdriver

alternatively, you can try writing a specific element:

    //label[1] is the first element.
    el =  await driver.findElement(By.xpath("//div[@class=\"facetContainerDiv\"]/div/label[1]/input")));
    await el.click();

More information can be found here: https://www.browserstack.com/guide/locators-in-selenium

How to return an array from a function?

how can i return a array in a c++ method and how must i declare it? int[] test(void); ??

This sounds like a simple question, but in C++ you have quite a few options. Firstly, you should prefer...

  • std::vector<>, which grows dynamically to however many elements you encounter at runtime, or

  • std::array<> (introduced with C++11), which always stores a number of elements specified at compile time,

...as they manage memory for you, ensuring correct behaviour and simplifying things considerably:

std::vector<int> fn()
{
    std::vector<int> x;
    x.push_back(10);
    return x;
}

std::array<int, 2> fn2()  // C++11
{
    return {3, 4};
}

void caller()
{
    std::vector<int> a = fn();
    const std::vector<int>& b = fn(); // extend lifetime but read-only
                                      // b valid until scope exit/return

    std::array<int, 2> c = fn2();
    const std::array<int, 2>& d = fn2();
}

The practice of creating a const reference to the returned data can sometimes avoid a copy, but normally you can just rely on Return Value Optimisation, or - for vector but not array - move semantics (introduced with C++11).

If you really want to use an inbuilt array (as distinct from the Standard library class called array mentioned above), one way is for the caller to reserve space and tell the function to use it:

void fn(int x[], int n)
{
    for (int i = 0; i < n; ++i)
        x[i] = n;
}

void caller()
{
    // local space on the stack - destroyed when caller() returns
    int x[10];
    fn(x, sizeof x / sizeof x[0]);

    // or, use the heap, lives until delete[](p) called...
    int* p = new int[10];
    fn(p, 10);
}

Another option is to wrap the array in a structure, which - unlike raw arrays - are legal to return by value from a function:

struct X
{
    int x[10];
};

X fn()
{
    X x;
    x.x[0] = 10;
    // ...
    return x;
}

void caller()
{
    X x = fn();
}

Starting with the above, if you're stuck using C++03 you might want to generalise it into something closer to the C++11 std::array:

template <typename T, size_t N>
struct array
{
    T& operator[](size_t n) { return x[n]; }
    const T& operator[](size_t n) const { return x[n]; }
    size_t size() const { return N; }
    // iterators, constructors etc....
  private:
    T x[N];
};

Another option is to have the called function allocate memory on the heap:

int* fn()
{
    int* p = new int[2];
    p[0] = 0;
    p[1] = 1;
    return p;
}

void caller()
{
    int* p = fn();
    // use p...
    delete[] p;
}

To help simplify the management of heap objects, many C++ programmers use "smart pointers" that ensure deletion when the pointer(s) to the object leave their scopes. With C++11:

std::shared_ptr<int> p(new int[2], [](int* p) { delete[] p; } );
std::unique_ptr<int[]> p(new int[3]);

If you're stuck on C++03, the best option is to see if the boost library is available on your machine: it provides boost::shared_array.

Yet another option is to have some static memory reserved by fn(), though this is NOT THREAD SAFE, and means each call to fn() overwrites the data seen by anyone keeping pointers from previous calls. That said, it can be convenient (and fast) for simple single-threaded code.

int* fn(int n)
{
    static int x[2];  // clobbered by each call to fn()
    x[0] = n;
    x[1] = n + 1;
    return x;  // every call to fn() returns a pointer to the same static x memory
}

void caller()
{
    int* p = fn(3);
    // use p, hoping no other thread calls fn() meanwhile and clobbers the values...
    // no clean up necessary...
}

What does "Table does not support optimize, doing recreate + analyze instead" mean?

The better option is create a new table copy the rows to the destination table, drop the actual table and rename the newly created table . This method is good for small tables,

How do I supply an initial value to a text field?

inside class,

  final usernameController = TextEditingController(text: 'bhanuka');

TextField,

   child: new TextField(
        controller: usernameController,
    ...
)

How can I "reset" an Arduino board?

For Arduino Yún users, try uploading via Ethernet/Wi-Fi (menu ToolsPort).

I had exactly the same problem, and I tried pretty much everything (apart from burning a new bootloader). I am surprised it worked, but I've uploaded an empty sketch without any problem.

Difference between const reference and normal parameter

With

 void DoWork(int n);

n is a copy of the value of the actual parameter, and it is legal to change the value of n within the function. With

void DoWork(const int &n);

n is a reference to the actual parameter, and it is not legal to change its value.

How to make g++ search for header files in a specific directory?

A/code.cpp

#include <B/file.hpp>

A/a/code2.cpp

#include <B/file.hpp>

Compile using:

g++ -I /your/source/root /your/source/root/A/code.cpp
g++ -I /your/source/root /your/source/root/A/a/code2.cpp

Edit:

You can use environment variables to change the path g++ looks for header files. From man page:

Some additional environments variables affect the behavior of the preprocessor.

   CPATH
   C_INCLUDE_PATH
   CPLUS_INCLUDE_PATH
   OBJC_INCLUDE_PATH

Each variable's value is a list of directories separated by a special character, much like PATH, in which to look for header files. The special character, "PATH_SEPARATOR", is target-dependent and determined at GCC build time. For Microsoft Windows-based targets it is a semicolon, and for almost all other targets it is a colon.

CPATH specifies a list of directories to be searched as if specified with -I, but after any paths given with -I options on the command line. This environment variable is used regardless of which language is being preprocessed.

The remaining environment variables apply only when preprocessing the particular language indicated. Each specifies a list of directories to be searched as if specified with -isystem, but after any paths given with -isystem options on the command line.

In all these variables, an empty element instructs the compiler to search its current working directory. Empty elements can appear at the beginning or end of a path. For instance, if the value of CPATH is ":/special/include", that has the same effect as -I. -I/special/include.

There are many ways you can change an environment variable. On bash prompt you can do this:

$ export CPATH=/your/source/root
$ g++ /your/source/root/A/code.cpp
$ g++ /your/source/root/A/a/code2.cpp

You can of course add this in your Makefile etc.

Working with select using AngularJS's ng-options

It can be useful. Bindings do not always work.

<select id="product" class="form-control" name="product" required
        ng-model="issue.productId"
        ng-change="getProductVersions()"
        ng-options="p.id as p.shortName for p in products"></select>

For example, you fill the options list source model from a REST service. A selected value was known before filling the list, and it was set. After executing the REST request with $http, the list option is done.

But the selected option is not set. For unknown reasons AngularJS in shadow $digest executing does not bind selected as it should be. I have got to use jQuery to set the selected. It`s important! AngularJS, in shadow, adds the prefix to the value of the attr "value" for generated by ng-repeat options. For int it is "number:".

$scope.issue.productId = productId;
function activate() {
    $http.get('/product/list')
       .then(function (response) {
           $scope.products = response.data;

           if (productId) {
               console.log("" + $("#product option").length);//for clarity
               $timeout(function () {
                   console.log("" + $("#product option").length);//for clarity
                   $('#product').val('number:'+productId);

               }, 200);
           }
       });
}

Error - SqlDateTime overflow. Must be between 1/1/1753 12:00:00 AM and 12/31/9999 11:59:59 PM

If you are using NHibernate, check that appropriate DateTime properties that are nullable are set to nullable in the mappings.

Run Executable from Powershell script with parameters

Here is an alternative method for doing multiple args. I use it when the arguments are too long for a one liner.

$app = 'C:\Program Files\MSBuild\test.exe'
$arg1 = '/genmsi'
$arg2 = '/f'
$arg3 = '$MySourceDirectory\src\Deployment\Installations.xml'

& $app $arg1 $arg2 $arg3

Which icon sizes should my Windows application's icon include?

In the case of Windows 10 this is not exactly accurate, in fact none of the answers on stackoverflow was, I found this out when I tried to use pixel art as an icon and it got rescaled when it was not supposed to(it was easy to see in this case cause of the interpolation and smoothing windows does) even thou I used the sizes from this post.

So I made an app and did the work on all DPI settings, see it here:
Windows 10 all icon resolutions on all DPI settings
You can also use my app to create icons, also with nearest neighbor interpolation with smoothing off, which is not done with any of the bad editors I have seen.

If you only want the resolutions:
16, 20, 24, 28, 30, 31, 32, 40, 42, 47, 48, 56, 60, 63, 84, 256
and you should use all PNG icons and anything you put in beside these it won't be displayed. See my post why.

Call JavaScript function from C#

You can call javascript functions from c# using Jering.Javascript.NodeJS, an open-source library by my organization:

string javascriptModule = @"
module.exports = (callback, x, y) => {  // Module must export a function that takes a callback as its first parameter
    var result = x + y; // Your javascript logic
    callback(null /* If an error occurred, provide an error object or message */, result); // Call the callback when you're done.
}";

// Invoke javascript
int result = await StaticNodeJSService.InvokeFromStringAsync<int>(javascriptModule, args: new object[] { 3, 5 });

// result == 8
Assert.Equal(8, result);

The library supports invoking directly from .js files as well. Say you have file C:/My/Directory/exampleModule.js containing:

module.exports = (callback, message) => callback(null, message);

You can invoke the exported function:

string result = await StaticNodeJSService.InvokeFromFileAsync<string>("C:/My/Directory/exampleModule.js", args: new[] { "test" });

// result == "test"
Assert.Equal("test", result);

phpmyadmin.pma_table_uiprefs doesn't exist

You just change following line in /etc/phpmyadmin/config.inc.php

$ Cfg ['Servers'] [$ i] ['table_uiprefs'] = ‘pma_table_uiprefs’;

to

$ cfg ['Servers'] [$ i] ['pma__table_uiprefs'] = ‘pma__table_uiprefs’;

And restart apache server with command,

sudo service apache2 restart

Make Bootstrap's Carousel both center AND responsive?

add this

.carousel .item img {
   left: -9999px;  /*important */
   right: -9999px;  /*important */
   margin: 0 auto;  /*important */
   max-width: none;  /*important */
   min-width: 100%;
   position: absolute;
}

And of course one of the parent divs needs to have a position:relative, but I believe it does by default.

See it here: http://paginacrestinului.ro/

Numpy ValueError: setting an array element with a sequence. This message may appear without the existing of a sequence?

You're getting the error message

ValueError: setting an array element with a sequence.

because you're trying to set an array element with a sequence. I'm not trying to be cute, there -- the error message is trying to tell you exactly what the problem is. Don't think of it as a cryptic error, it's simply a phrase. What line is giving the problem?

kOUT[i]=func(TempLake[i],Z)

This line tries to set the ith element of kOUT to whatever func(TempLAke[i], Z) returns. Looking at the i=0 case:

In [39]: kOUT[0]
Out[39]: 0.0

In [40]: func(TempLake[0], Z)
Out[40]: array([ 0.,  0.,  0.,  0.])

You're trying to load a 4-element array into kOUT[0] which only has a float. Hence, you're trying to set an array element (the left hand side, kOUT[i]) with a sequence (the right hand side, func(TempLake[i], Z)).

Probably func isn't doing what you want, but I'm not sure what you really wanted it to do (and don't forget you can usually use vectorized operations like A*B rather than looping in numpy.) That should explain the problem, anyway.

Upload file to SFTP using PowerShell

You didn't tell us what particular problem do you have with the WinSCP, so I can really only repeat what's in WinSCP documentation.

  • Download WinSCP .NET assembly.
    The latest package as of now is WinSCP-5.17.10-Automation.zip;

  • Extract the .zip archive along your script;

  • Use a code like this (based on the official PowerShell upload example):

      # Load WinSCP .NET assembly
      Add-Type -Path "WinSCPnet.dll"
    
      # Setup session options
      $sessionOptions = New-Object WinSCP.SessionOptions -Property @{
          Protocol = [WinSCP.Protocol]::Sftp
          HostName = "example.com"
          UserName = "user"
          Password = "mypassword"
          SshHostKeyFingerprint = "ssh-rsa 2048 xxxxxxxxxxx...="
      }
    
      $session = New-Object WinSCP.Session
    
      try
      {
          # Connect
          $session.Open($sessionOptions)
    
          # Upload
          $session.PutFiles("C:\FileDump\export.txt", "/Outbox/").Check()
      }
      finally
      {
          # Disconnect, clean up
          $session.Dispose()
      }
    

You can have WinSCP generate the PowerShell script for the upload for you:

  • Login to your server with WinSCP GUI;
  • Navigate to the target directory in the remote file panel;
  • Select the file for upload in the local file panel;
  • Invoke the Upload command;
  • On the Transfer options dialog, go to Transfer Settings > Generate Code;
  • On the Generate transfer code dialog, select the .NET assembly code tab;
  • Choose PowerShell language.

You will get a code like above with all session and transfer settings filled in.

Generate transfer code dialog

(I'm the author of WinSCP)

How to run mysql command on bash?

This one worked, double quotes when $user and $password are outside single quotes. Single quotes when inside a single quote statement.

mysql --user="$user" --password="$password" --database="$user" --execute='DROP DATABASE '$user'; CREATE DATABASE '$user';'

How to open local file on Jupyter?

To start Jupyter Notebook in Windows:

  • open a Windows cmd (win + R and return cmd)
  • change directory to the desired file path (cd file-path)
  • give command jupyter notebook

You can further navigate from the UI of Jupyter notebook after you launch it (if you are not directly launching the right file.)
OR you can directly drag and drop the file to the cmd, to open the file.

C:\Users\kushalatreya>jupyter notebook "C:\Users\kushalatreya\Downloads\Material\PythonCourseFolder\PythonCourse-DataTypes.ipynb"

How to implement a Keyword Search in MySQL?

Personally, I wouldn't use the LIKE string comparison on the ID field or any other numeric field. It doesn't make sense for a search for ID# "216" to return 16216, 21651, 3216087, 5321668..., and so on and so forth; likewise with salary.

Also, if you want to use prepared statements to prevent SQL injections, you would use a query string like:

SELECT * FROM job WHERE `position` LIKE CONCAT('%', ? ,'%') OR ...

Return Bit Value as 1/0 and NOT True/False in SQL Server

This can be changed to 0/1 through using CASE WHEN like this example:

SELECT 
 CASE WHEN SchemaName.TableName.BitFieldName = 'true' THEN 1 ELSE 0 END AS 'bit Value' 
 FROM SchemaName.TableName

How do I create a local database inside of Microsoft SQL Server 2014?

Warning! SQL Server 14 Express, SQL Server Management Studio, and SQL 2014 LocalDB are separate downloads, make sure you actually installed SQL Server and not just the Management Studio! SQL Server 14 express with LocalDB download link

Youtube video about entire process.
Writeup with pictures about installing SQL Server

How to select a local server:

When you are asked to connect to a 'database server' right when you open up SQL Server Management Studio do this:

1) Make sure you have Server Type: Database

2) Make sure you have Authentication: Windows Authentication (no username & password)

3) For the server name field look to the right and select the drop down arrow, click 'browse for more'

4) New window pops up 'Browse for Servers', make sure to pick 'Local Servers' tab and under 'Database Engine' you will have the local server you set up during installation of SQL Server 14

How do I create a local database inside of Microsoft SQL Server 2014?

1) After you have connected to a server, bring up the Object Explorer toolbar under 'View' (Should open by default)

2) Now simply right click on 'Databases' and then 'Create new Database' to be taken through the database creation tools!

Where is svcutil.exe in Windows 7?

With latest version of windows (e.g. Windows 10, other servers), type/search for "Developers Command prompt.." It will pop up the relevant command prompt for the Visual Studio version.

e.g. Developer Command Prompt for VS 2015

More here https://msdn.microsoft.com/en-us/library/ms229859(v=vs.110).aspx

Use string value from a cell to access worksheet of same name

You need INDIRECT function:

=INDIRECT("'"&A5&"'!G7")

Can you use Microsoft Entity Framework with Oracle?

In case you don't know it already, Oracle has released ODP.NET which supports Entity Framework. It doesn't support code first yet though.

http://www.oracle.com/technetwork/topics/dotnet/index-085163.html

Index Error: list index out of range (Python)

Generally it means that you are providing an index for which a list element does not exist.

E.g, if your list was [1, 3, 5, 7], and you asked for the element at index 10, you would be well out of bounds and receive an error, as only elements 0 through 3 exist.

Is there Selected Tab Changed Event in the standard WPF Tab Control

I tied this in the handler to make it work:

void TabControl_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    if (e.Source is TabControl)
    {
      //do work when tab is changed
    }
}

How to create the most compact mapping n ? isprime(n) up to a limit N?

You could try something like this.

def main():
    try:
        user_in = int(input("Enter a number to determine whether the number is prime or not: "))
    except ValueError:
        print()
        print("You must enter a number!")
        print()
        return
    list_range = list(range(2,user_in+1))
    divisor_list = []
    for number in list_range:
        if user_in%number==0:
            divisor_list.append(number)
    if len(divisor_list) < 2:
        print(user_in, "is a prime number!")
        return
    else:
        print(user_in, "is not a prime number!")
        return
main()

How to create a simple checkbox in iOS?

On iOS there is the switch UI component instead of a checkbox, look into the UISwitch class. The property on (boolean) can be used to determine the state of the slider and about the saving of its state: That depends on how you save your other stuff already, its just saving a boolean value.

Keep CMD open after BAT file executes

In Windows add '& Pause' to the end of your command in the file.

Django MEDIA_URL and MEDIA_ROOT

This if for Django 1.10:

 if settings.DEBUG:
    urlpatterns += staticfiles_urlpatterns()
    urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)

How can I invert color using CSS?

Here is a different approach using mix-blend-mode: difference, that will actually invert whatever the background is, not just a single colour:

_x000D_
_x000D_
div {_x000D_
  background-image: linear-gradient(to right, red, yellow, green, cyan, blue, violet);_x000D_
}_x000D_
p {_x000D_
  color: white;_x000D_
  mix-blend-mode: difference;_x000D_
}
_x000D_
<div>_x000D_
  <p>Lorem ipsum dolor sit amet, consectetur adipiscit elit, sed do</p>_x000D_
</div>
_x000D_
_x000D_
_x000D_

REACT - toggle class onclick

React has a concept of components state, so if you want to switch it, do a setState:

constructor(props) {
  super(props);

  this.addActiveClass= this.addActiveClass.bind(this);
  this.state = {
    isActive: false
  }
}

addActiveClass() {
  this.setState({
    isActive: true
  })
}

In your component use this.state.isActive to render what you need.

This gets more complicated when you want to set state in component#1 and use it in component#2. Just dig more into react unidirectional data flow and possibly redux that will help you handle it.

Constructor in an Interface?

A problem that you get when you allow constructors in interfaces comes from the possibility to implement several interfaces at the same time. When a class implements several interfaces that define different constructors, the class would have to implement several constructors, each one satisfying only one interface, but not the others. It will be impossible to construct an object that calls each of these constructors.

Or in code:

interface Named { Named(String name); }
interface HasList { HasList(List list); }

class A implements Named, HasList {

  /** implements Named constructor.
   * This constructor should not be used from outside, 
   * because List parameter is missing
   */
  public A(String name)  { 
    ...
  }

  /** implements HasList constructor.
   * This constructor should not be used from outside, 
   * because String parameter is missing
   */
  public A(List list) {
    ...
  }

  /** This is the constructor that we would actually 
   * need to satisfy both interfaces at the same time
   */ 
  public A(String name, List list) {
    this(name);
    // the next line is illegal; you can only call one other super constructor
    this(list); 
  }
}

How to putAll on Java hashMap contents of one to another, but not replace existing keys and values?

Using Guava's Maps class' utility methods to compute the difference of 2 maps you can do it in a single line, with a method signature which makes it more clear what you are trying to accomplish:

public static void main(final String[] args) {
    // Create some maps
    final Map<Integer, String> map1 = new HashMap<Integer, String>();
    map1.put(1, "Hello");
    map1.put(2, "There");
    final Map<Integer, String> map2 = new HashMap<Integer, String>();
    map2.put(2, "There");
    map2.put(3, "is");
    map2.put(4, "a");
    map2.put(5, "bird");

    // Add everything in map1 not in map2 to map2
    map2.putAll(Maps.difference(map1, map2).entriesOnlyOnLeft());
}

What is a file with extension .a?

.a files are static libraries typically generated by the archive tool. You usually include the header files associated with that static library and then link to the library when you are compiling.

Set Page Title using PHP

You need to set the value of $title before echoing it.

Also, you should really sanitize any data before using it in queries as this is a security risk

Whoops, looks like something went wrong. Laravel 5.0

in process of uploading env file to cpanel,

sometimes the dot is taken out and this may raised the error.

this solution worked for me.

go to your cpanel and rename env file to .env

find files by extension, *.html under a folder in nodejs

my two pence, using map in place of for-loop

var path = require('path'), fs = require('fs');

var findFiles = function(folder, pattern = /.*/, callback) {
  var flist = [];

  fs.readdirSync(folder).map(function(e){ 
    var fname = path.join(folder, e);
    var fstat = fs.lstatSync(fname);
    if (fstat.isDirectory()) {
      // don't want to produce a new array with concat
      Array.prototype.push.apply(flist, findFiles(fname, pattern, callback)); 
    } else {
      if (pattern.test(fname)) {
        flist.push(fname);
        if (callback) {
          callback(fname);
        }
      }
    }
  });
  return flist;
};

// HTML files   
var html_files = findFiles(myPath, /\.html$/, function(o) { console.log('look what we have found : ' + o} );

// All files
var all_files = findFiles(myPath);

Passing environment-dependent variables in webpack

Just another option, if you want to use only a cli interface, just use the define option of webpack. I add the following script in my package.json :

"build-production": "webpack -p --define process.env.NODE_ENV='\"production\"' --progress --colors"

So I just have to run npm run build-production.

How to implement class constants?

Constants can be declare outside of classes and use within your class. Otherwise the get property is a nice workaround

const MY_CONSTANT: string = "wazzup";

export class MyClass {

    public myFunction() {

        alert(MY_CONSTANT);
    }
}

Set line height in Html <p> to make the html looks like a office word when <p> has different font sizes

Actually, you can achieve this pretty easy. Simply specify the line height as a number:

<p style="line-height:1.5">
    <span style="font-size:12pt">The quick brown fox jumps over the lazy dog.</span><br />
    <span style="font-size:24pt">The quick brown fox jumps over the lazy dog.</span>
</p>

The difference between number and percentage in the context of the line-height CSS property is that the number value is inherited by the descendant elements, but the percentage value is first computed for the current element using its font size and then this computed value is inherited by the descendant elements.

For more information about the line-height property, which indeed is far more complex than it looks like at first glance, I recommend you take a look at this online presentation.

What are the advantages of NumPy over regular Python lists?

Alex mentioned memory efficiency, and Roberto mentions convenience, and these are both good points. For a few more ideas, I'll mention speed and functionality.

Functionality: You get a lot built in with NumPy, FFTs, convolutions, fast searching, basic statistics, linear algebra, histograms, etc. And really, who can live without FFTs?

Speed: Here's a test on doing a sum over a list and a NumPy array, showing that the sum on the NumPy array is 10x faster (in this test -- mileage may vary).

from numpy import arange
from timeit import Timer

Nelements = 10000
Ntimeits = 10000

x = arange(Nelements)
y = range(Nelements)

t_numpy = Timer("x.sum()", "from __main__ import x")
t_list = Timer("sum(y)", "from __main__ import y")
print("numpy: %.3e" % (t_numpy.timeit(Ntimeits)/Ntimeits,))
print("list:  %.3e" % (t_list.timeit(Ntimeits)/Ntimeits,))

which on my systems (while I'm running a backup) gives:

numpy: 3.004e-05
list:  5.363e-04

How do I set a fixed background image for a PHP file?

It's not a good coding to put PHP code into CSS

body
{
    background-image:url('bg.png');
}

that's it

"Cannot allocate an object of abstract type" error

You must have some virtual function declared in one of the parent classes and never implemented in any of the child classes. Make sure that all virtual functions are implemented somewhere in the inheritence chain. If a class's definition includes a pure virtual function that is never implemented, an instance of that class cannot ever be constructed.

Regular Expressions: Is there an AND operator?

Use a non-consuming regular expression.

The typical (i.e. Perl/Java) notation is:

(?=expr)

This means "match expr but after that continue matching at the original match-point."

You can do as many of these as you want, and this will be an "and." Example:

(?=match this expression)(?=match this too)(?=oh, and this)

You can even add capture groups inside the non-consuming expressions if you need to save some of the data therein.

How to find the Number of CPU Cores via .NET/C#?

Environment.ProcessorCount should give you the number of cores on the local machine.

Firebase FCM force onTokenRefresh() to be called

    [Service]
[IntentFilter(new[] { "com.google.firebase.INSTANCE_ID_EVENT" })]
class MyFirebaseIIDService: FirebaseInstanceIdService
{
    const string TAG = "MyFirebaseIIDService";
    NotificationHub hub;

    public override void OnTokenRefresh()
    {
        var refreshedToken = FirebaseInstanceId.Instance.Token;
        Log.Debug(TAG, "FCM token: " + refreshedToken);
        SendRegistrationToServer(refreshedToken);
    }

    void SendRegistrationToServer(string token)
    {
        // Register with Notification Hubs
        hub = new NotificationHub(Constants.NotificationHubName,
                                    Constants.ListenConnectionString, this);
        Employee employee = JsonConvert.DeserializeObject<Employee>(Settings.CurrentUser);
        //if user is not logged in 
        if (employee != null)
        {
            var tags = new List<string>() { employee.Email};
            var regID = hub.Register(token, tags.ToArray()).RegistrationId;

            Log.Debug(TAG, $"Successful registration of ID {regID}");
        }
        else
        {
            FirebaseInstanceId.GetInstance(Firebase.FirebaseApp.Instance).DeleteInstanceId();
            hub.Unregister();
        }
    }
}

Basic example of using .ajax() with JSONP?

JSONP is really a simply trick to overcome XMLHttpRequest same domain policy. (As you know one cannot send AJAX (XMLHttpRequest) request to a different domain.)

So - instead of using XMLHttpRequest we have to use script HTMLl tags, the ones you usually use to load JS files, in order for JS to get data from another domain. Sounds weird?

Thing is - turns out script tags can be used in a fashion similar to XMLHttpRequest! Check this out:

script = document.createElement("script");
script.type = "text/javascript";
script.src = "http://www.someWebApiServer.com/some-data";

You will end up with a script segment that looks like this after it loads the data:

<script>
{['some string 1', 'some data', 'whatever data']}
</script>

However this is a bit inconvenient, because we have to fetch this array from script tag. So JSONP creators decided that this will work better (and it is):

script = document.createElement("script");
script.type = "text/javascript";
script.src = "http://www.someWebApiServer.com/some-data?callback=my_callback";

Notice my_callback function over there? So - when JSONP server receives your request and finds callback parameter - instead of returning plain JS array it'll return this:

my_callback({['some string 1', 'some data', 'whatever data']});

See where the profit is: now we get automatic callback (my_callback) that'll be triggered once we get the data. That's all there is to know about JSONP: it's a callback and script tags.


NOTE:
These are simple examples of JSONP usage, these are not production ready scripts.

RAW JavaScript demonstration (simple Twitter feed using JSONP):

<html>
    <head>
    </head>
    <body>
        <div id = 'twitterFeed'></div>
        <script>
        function myCallback(dataWeGotViaJsonp){
            var text = '';
            var len = dataWeGotViaJsonp.length;
            for(var i=0;i<len;i++){
                twitterEntry = dataWeGotViaJsonp[i];
                text += '<p><img src = "' + twitterEntry.user.profile_image_url_https +'"/>' + twitterEntry['text'] + '</p>'
            }
            document.getElementById('twitterFeed').innerHTML = text;
        }
        </script>
        <script type="text/javascript" src="http://twitter.com/status/user_timeline/padraicb.json?count=10&callback=myCallback"></script>
    </body>
</html>


Basic jQuery example (simple Twitter feed using JSONP):

<html>
    <head>
        <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js"></script>
        <script>
            $(document).ready(function(){
                $.ajax({
                    url: 'http://twitter.com/status/user_timeline/padraicb.json?count=10',
                    dataType: 'jsonp',
                    success: function(dataWeGotViaJsonp){
                        var text = '';
                        var len = dataWeGotViaJsonp.length;
                        for(var i=0;i<len;i++){
                            twitterEntry = dataWeGotViaJsonp[i];
                            text += '<p><img src = "' + twitterEntry.user.profile_image_url_https +'"/>' + twitterEntry['text'] + '</p>'
                        }
                        $('#twitterFeed').html(text);
                    }
                });
            })
        </script>
    </head>
    <body>
        <div id = 'twitterFeed'></div>
    </body>
</html>


JSONP stands for JSON with Padding. (very poorly named technique as it really has nothing to do with what most people would think of as “padding”.)

BootStrap : Uncaught TypeError: $(...).datetimepicker is not a function

This is a bit late but I know it will help someone:

If you are using datetimepicker make sure you include the right CSS and JS files. datetimepicker uses(Take note of their names);

https://cdnjs.cloudflare.com/ajax/libs/bootstrap-datetimepicker/4.17.37/css/bootstrap-datetimepicker.css

and

https://cdnjs.cloudflare.com/ajax/libs/bootstrap-datetimepicker/4.17.37/js/bootstrap-datetimepicker.min.js

On the above question asked by @mindfreak,The main problem is due to the imported files.