Programs & Examples On #Live mesh

filter out multiple criteria using excel vba

Here an option using a list written on some range, populating an array that will be fiiltered. The information will be erased then the columns sorted.

Sub Filter_Out_Values()

'Automation to remove some codes from the list
Dim ws, ws1 As Worksheet
Dim myArray() As Variant
Dim x, lastrow As Long
Dim cell As Range

Set ws = Worksheets("List")
Set ws1 = Worksheets(8)
lastrow = ws.Cells(Application.Rows.Count, 1).End(xlUp).Row

'Go through the list of codes to exclude
For Each cell In ws.Range("A2:A" & lastrow)

    If cell.Offset(0, 2).Value = "X" Then 'If the Code is associated with "X"
        ReDim Preserve myArray(x) 'Initiate array
        myArray(x) = CStr(cell.Value) 'Populate the array with the code
        x = x + 1 'Increase array capacity
        ReDim Preserve myArray(x) 'Redim array
    End If

Next cell

lastrow = ws1.Cells(Application.Rows.Count, 1).End(xlUp).Row
ws1.Range("C2:C" & lastrow).AutoFilter field:=3, Criteria1:=myArray, Operator:=xlFilterValues
ws1.Range("A2:Z" & lastrow).SpecialCells(xlCellTypeVisible).ClearContents
ws1.Range("A2:Z" & lastrow).AutoFilter field:=3

'Sort columns
lastrow = ws1.Cells(Application.Rows.Count, 1).End(xlUp).Row
'Sort with 2 criteria
With ws1.Range("A1:Z" & lastrow)
    .Resize(lastrow).Sort _
    key1:=ws1.Columns("B"), order1:=xlAscending, DataOption1:=xlSortNormal, _
    key2:=ws1.Columns("D"), order1:=xlAscending, DataOption1:=xlSortNormal, _
    Header:=xlYes, MatchCase:=False, Orientation:=xlTopToBottom, SortMethod:=xlPinYin
End With

End Sub

PHP 5 disable strict standards error

In php.ini set :

error_reporting = E_ALL & ~E_NOTICE & ~E_STRICT

Cannot edit in read-only editor VS Code

  1. Go to File > Preference > Settings then
  2. type: run code and scroll down until you see code-runner: Run in terminal, There will be multiple options called "code-runner". In that you can find the option mentioned below.
  3. just check "Whether to run code in integrated terminal" and
  4. restart vscode.

For Mac users, it is Code > Preference > Settings.

Can I load a .NET assembly at runtime and instantiate a type knowing only the name?

Yes. I don't have any examples that I've done personally available right now. I'll post later when I find some. Basically you'll use reflection to load the assembly and then to pull whatever types you need for it.

In the meantime, this link should get you started:

Using reflection to load unreferenced assemblies at runtime

What does "O(1) access time" mean?

O(1) means Random Access. In any Random Access Memory, the time taken to access any element at any location is the same. Here time can be any integer, but the only thing to remember is time taken to retrieve the element at (n-1)th or nth location will be same(ie constant).

Whereas O(n) is dependent on the size of n.

How to stop an app on Heroku?

To add to the answers above: if you want to stop Dyno using admin panel, the current solution on free tier:

  1. Open App
  2. In Overview tab, in "Dyno formation" section click on "Configure Dynos"
  3. In the needed row of "Free Dynos" section, click on the pencil icon on the right
  4. Click on the blue on/off control, and then click on "Confirm"

Hope this helps.

Twitter Bootstrap Button Text Word Wrap

FWIW, in Boostrap 4.4, you can add .text-wrap style to things like buttons:

   <a href="#" class="btn btn-primary text-wrap">Lorem ipsum dolor sit amet, consectetur adipiscing elit.</a>

https://getbootstrap.com/docs/4.4/utilities/text/#text-wrapping-and-overflow

Get String in YYYYMMDD format from JS date object?

I usually use the code below when I need to do this.

var date = new Date($.now());
var dateString = (date.getFullYear() + '-'
    + ('0' + (date.getMonth() + 1)).slice(-2)
    + '-' + ('0' + (date.getDate())).slice(-2));
console.log(dateString); //Will print "2015-09-18" when this comment was written

To explain, .slice(-2) gives us the last two characters of the string.

So no matter what, we can add "0" to the day or month, and just ask for the last two since those are always the two we want.

So if the MyDate.getMonth() returns 9, it will be:

("0" + "9") // Giving us "09"

so adding .slice(-2) on that gives us the last two characters which is:

("0" + "9").slice(-2)

"09"

But if date.getMonth() returns 10, it will be:

("0" + "10") // Giving us "010"

so adding .slice(-2) gives us the last two characters, or:

("0" + "10").slice(-2)

"10"

What is MVC and what are the advantages of it?

![mvc architecture][1]

Model–view–controller (MVC) is a software architectural pattern for implementing user interfaces. It divides a given software application into three interconnected parts, so as to separate internal representations of information from the ways that information is presented to or accepted from the user.

How do I set the default value for an optional argument in Javascript?

ES6 Update - ES6 (ES2015 specification) allows for default parameters

The following will work just fine in an ES6 (ES015) environment...

function(nodeBox, str="hai")
{
  // ...
}

what does the __file__ variable mean/do?

When a module is loaded from a file in Python, __file__ is set to its path. You can then use that with other functions to find the directory that the file is located in.

Taking your examples one at a time:

A = os.path.join(os.path.dirname(__file__), '..')
# A is the parent directory of the directory where program resides.

B = os.path.dirname(os.path.realpath(__file__))
# B is the canonicalised (?) directory where the program resides.

C = os.path.abspath(os.path.dirname(__file__))
# C is the absolute path of the directory where the program resides.

You can see the various values returned from these here:

import os
print(__file__)
print(os.path.join(os.path.dirname(__file__), '..'))
print(os.path.dirname(os.path.realpath(__file__)))
print(os.path.abspath(os.path.dirname(__file__)))

and make sure you run it from different locations (such as ./text.py, ~/python/text.py and so forth) to see what difference that makes.


I just want to address some confusion first. __file__ is not a wildcard it is an attribute. Double underscore attributes and methods are considered to be "special" by convention and serve a special purpose.

http://docs.python.org/reference/datamodel.html shows many of the special methods and attributes, if not all of them.

In this case __file__ is an attribute of a module (a module object). In Python a .py file is a module. So import amodule will have an attribute of __file__ which means different things under difference circumstances.

Taken from the docs:

__file__ is the pathname of the file from which the module was loaded, if it was loaded from a file. The __file__ attribute is not present for C modules that are statically linked into the interpreter; for extension modules loaded dynamically from a shared library, it is the pathname of the shared library file.

In your case the module is accessing it's own __file__ attribute in the global namespace.

To see this in action try:

# file: test.py

print globals()
print __file__

And run:

python test.py

{'__builtins__': <module '__builtin__' (built-in)>, '__name__': '__main__', '__file__':
 'test_print__file__.py', '__doc__': None, '__package__': None}
test_print__file__.py

Docker: unable to prepare context: unable to evaluate symlinks in Dockerfile path: GetFileAttributesEx

I had originally created my Dockerfile in PowerShell and though I didn't see an extension on the file it showed as a PS File Type...once I created the file from Notepad++ being sure to select the "All types (.)" File Type with no extension on the File Name (Dockerfile). That allowed my image build command to complete successfully....Just make sure your Dockerfile has a Type of "File"...

How to fix 'android.os.NetworkOnMainThreadException'?

We can also use RxJava to move network operations to a background thread. And it's fairly simple as well.

webService.doSomething(someData)
          .subscribeOn(Schedulers.newThread())-- This for background thread
          .observeOn(AndroidSchedulers.mainThread()) -- for callback on UI              
          .subscribe(result -> resultText.setText("It worked!"),
              e -> handleError(e));

You can do a lot more stuff with RxJava.Here are some links for RxJava. Feel free to dig in.

RxJava Async task in Android

http://blog.stablekernel.com/replace-asynctask-asynctaskloader-rx-observable-rxjava-android-patterns/

How to convert SSH keypairs generated using PuTTYgen (Windows) into key-pairs used by ssh-agent and Keychain (Linux)

If all you have is a public key from a user in PuTTY-style format, you can convert it to standard openssh format like so:

ssh-keygen -i -f keyfile.pub > newkeyfile.pub

References

Copy of article

I keep forgetting this so I'm gonna write it here. Non-geeks, just keep walking.

The most common way to make a key on Windows is using Putty/Puttygen. Puttygen provides a neat utility to convert a linux private key to Putty format. However, what isn't addressed is that when you save the public key using puttygen it won't work on a linux server. Windows puts some data in different areas and adds line breaks.

The Solution: When you get to the public key screen in creating your key pair in puttygen, copy the public key and paste it into a text file with the extension .pub. You will save you sysadmin hours of frustration reading posts like this.

HOWEVER, sysadmins, you invariably get the wonky key file that throws no error message in the auth log except, no key found, trying password; even though everyone else's keys are working fine, and you've sent this key back to the user 15 times.

ssh-keygen -i -f keyfile.pub > newkeyfile.pub

Should convert an existing puttygen public key to OpenSSH format.

How to send a pdf file directly to the printer using JavaScript?

I think this Library of JavaScript might Help you:

It's called Print.js

First Include

<script src="print.js"></script>
<link rel="stylesheet" type="text/css" href="print.css">

It's basic usage is to call printJS() and just pass in a PDF document url: printJS('docs/PrintJS.pdf')

What I did was something like this, this will also show "Loading...." if PDF document is too large.

<button type="button" onclick="printJS({printable:'docs/xx_large_printjs.pdf', type:'pdf', showModal:true})">
    Print PDF with Message
</button>

However keep in mind that:

Firefox currently doesn't allow printing PDF documents using iframes. There is an open bug in Mozilla's website about this. When using Firefox, Print.js will open the PDF file into a new tab.

Excel - Shading entire row based on change of value

you could use this formular to do the job -> get the CellValue for the specific row by typing: = indirect("$A&Cell()) depending on which column you have to check, you have to change the $A

For Example -> You could use a customized VBA Function in the Background:

Public Function IstDatum(Zelle) As Boolean IstDatum = False If IsDate(Zelle) Then IstDatum = True End Function

I need it to check for a date-entry in column A:

=IstDatum(INDIREKT("$A"&ZEILE()))

have a look at the picture:

Search text in fields in every table of a MySQL database

If you are avoiding stored procedures like the plague, or are unable to do a mysql_dump due to permissions, or running into other various reasons.

I would suggest a three-step approach like this:

1) Where this query builds a bunch of queries as a result set.

# =================
# VAR/CHAR SEARCH
# =================
# BE ADVISED USE ANY OF THESE WITH CAUTION
# DON'T RUN ON YOUR PRODUCTION SERVER 
# ** USE AN ALTERNATE BACKUP **

SELECT 
    CONCAT('SELECT * FROM ', A.TABLE_SCHEMA, '.', A.TABLE_NAME, 
           ' WHERE ', A.COLUMN_NAME, ' LIKE \'%stuff%\';') 
FROM INFORMATION_SCHEMA.COLUMNS A
WHERE 
            A.TABLE_SCHEMA != 'mysql' 
AND     A.TABLE_SCHEMA != 'innodb' 
AND     A.TABLE_SCHEMA != 'performance_schema' 
AND     A.TABLE_SCHEMA != 'information_schema'
AND     
        (
            A.DATA_TYPE LIKE '%text%'
        OR  
            A.DATA_TYPE LIKE '%char%'
        )
;

.

# =================
# NUMBER SEARCH
# =================
# BE ADVISED USE WITH CAUTION

SELECT 
    CONCAT('SELECT * FROM ', A.TABLE_SCHEMA, '.', A.TABLE_NAME, 
           ' WHERE ', A.COLUMN_NAME, ' IN (\'%1234567890%\');') 
FROM INFORMATION_SCHEMA.COLUMNS A
WHERE 
            A.TABLE_SCHEMA != 'mysql' 
AND     A.TABLE_SCHEMA != 'innodb' 
AND     A.TABLE_SCHEMA != 'performance_schema' 
AND     A.TABLE_SCHEMA != 'information_schema'
AND     A.DATA_TYPE IN ('bigint','int','smallint','tinyint','decimal','double')
;

.

# =================
# BLOB SEARCH
# =================
# BE ADVISED THIS IS CAN END HORRIFICALLY IF YOU DONT KNOW WHAT YOU ARE DOING
# YOU SHOULD KNOW IF YOU HAVE FULL TEXT INDEX ON OR NOT
# MISUSE AND YOU COULD CRASH A LARGE SERVER
SELECT 
    CONCAT('SELECT CONVERT(',A.COLUMN_NAME, ' USING utf8) FROM ', A.TABLE_SCHEMA, '.', A.TABLE_NAME, 
           ' WHERE CONVERT(',A.COLUMN_NAME, ' USING utf8) IN (\'%someText%\');') 
FROM INFORMATION_SCHEMA.COLUMNS A
WHERE 
            A.TABLE_SCHEMA != 'mysql' 
AND     A.TABLE_SCHEMA != 'innodb' 
AND     A.TABLE_SCHEMA != 'performance_schema' 
AND     A.TABLE_SCHEMA != 'information_schema'
AND     A.DATA_TYPE LIKE '%blob%'
;

Results should look like this:

Copy these results into another query window

2) You can then just Right Click and use the Copy Row (tab-separated)

enter image description here

3) Paste results in a new query window and run to your heart's content.

Detail: I exclude system schema's that you may not usually see in your workbench unless you have the option Show Metadata and Internal Schemas checked.

I did this to provide a quick way to ANALYZE an entire HOST or DB if needed or to run OPTIMIZE statements to support performance improvements.

I'm sure there are different ways you may go about doing this but here’s what works for me:

-- ========================================== DYNAMICALLY FIND TABLES AND CREATE A LIST OF QUERIES IN THE RESULTS TO ANALYZE THEM
SELECT CONCAT('ANALYZE TABLE ', TABLE_SCHEMA, '.', TABLE_NAME, ';') FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'dbname';

-- ========================================== DYNAMICALLY FIND TABLES AND CREATE A LIST OF QUERIES IN THE RESULTS TO OPTIMIZE THEM
SELECT CONCAT('OPTIMIZE TABLE ', TABLE_SCHEMA, '.', TABLE_NAME, ';') FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'dbname';

Tested On MySQL Version: 5.6.23

WARNING: DO NOT RUN THIS IF:

  1. You are concerned with causing Table-locks (keep an eye on your client-connections)
  2. You are unsure about what you are doing.

  3. You are trying to anger you DBA. (you may have people at your desk with the quickness.)

Cheers, Jay ;-]

How do I detect if a user is already logged in Firebase?

use Firebase.getAuth(). It returns the current state of the Firebase client. Otherwise the return value is nullHere are the docs: https://www.firebase.com/docs/web/api/firebase/getauth.html

How to test an Oracle Stored Procedure with RefCursor return type?

Something like

create or replace procedure my_proc( p_rc OUT SYS_REFCURSOR )
as
begin
  open p_rc
   for select 1 col1
         from dual;
end;
/

variable rc refcursor;
exec my_proc( :rc );
print rc;

will work in SQL*Plus or SQL Developer. I don't have any experience with Embarcardero Rapid XE2 so I have no idea whether it supports SQL*Plus commands like this.

How to rotate x-axis tick labels in Pandas barplot

Pass param rot=0 to rotate the xticks:

import matplotlib
matplotlib.style.use('ggplot')
import matplotlib.pyplot as plt
import pandas as pd

df = pd.DataFrame({ 'celltype':["foo","bar","qux","woz"], 's1':[5,9,1,7], 's2':[12,90,13,87]})
df = df[["celltype","s1","s2"]]
df.set_index(["celltype"],inplace=True)
df.plot(kind='bar',alpha=0.75, rot=0)
plt.xlabel("")
plt.show()

yields plot:

enter image description here

What is the different between RESTful and RESTless

Here are summarized the key differences between RESTful and RESTless web services:

1. Protocol

  • RESTful services use REST architectural style,
  • RESTless services use SOAP protocol.

2. Business logic / Functionality

  • RESTful services use URL to expose business logic,
  • RESTless services use the service interface to expose business logic.

3. Security

  • RESTful inherits security from the underlying transport protocols,
  • RESTless defines its own security layer, thus it is considered as more secure.

4. Data format

  • RESTful supports various data formats such as HTML, JSON, text, etc,
  • RESTless supports XML format.

5. Flexibility

  • RESTful is easier and flexible,
  • RESTless is not as easy and flexible.

6. Bandwidth

  • RESTful services consume less bandwidth and resource,
  • RESTless services consume more bandwidth and resources.

How to get last N records with activerecord?

Updated Answer (2020)

You can get last N records simply by using last method:

Record.last(N)

Example:

User.last(5)

Returns 5 users in descending order by their id.

Deprecated (Old Answer)

An active record query like this I think would get you what you want ('Something' is the model name):

Something.find(:all, :order => "id desc", :limit => 5).reverse

edit: As noted in the comments, another way:

result = Something.find(:all, :order => "id desc", :limit => 5)

while !result.empty?
        puts result.pop
end

WPF Data Binding and Validation Rules Best Practices

Also check this article. Supposedly Microsoft released their Enterprise Library (v4.0) from their patterns and practices where they cover the validation subject but god knows why they didn't included validation for WPF, so the blog post I'm directing you to, explains what the author did to adapt it. Hope this helps!

Retrieve the position (X,Y) of an HTML element relative to the browser window

If you want it done only in javascript, here are some one liners using getBoundingClientRect()

window.scrollY + document.querySelector('#elementId').getBoundingClientRect().top // Y

window.scrollX + document.querySelector('#elementId').getBoundingClientRect().left // X

The first line will return offsetTop say Y relative to document. The second line will return offsetLeft say X relative to document.

getBoundingClientRect() is a javascript function that returns the position of the element relative to viewport of window.

size of uint8, uint16 and uint32?

uint8, uint16, uint32, and uint64 are probably Microsoft-specific types.

As of the 1999 standard, C supports standard typedefs with similar meanings, defined in <stdint.h>: uint8_t, uint16_t, uint32_t, and uint64_t. I'll assume that the Microsoft-specific types are defined similarly. Microsoft does support <stdint.h>, at least as of Visual Studio 2010, but older code may use uint8 et al.

The predefined types char, short, int et al have sizes that vary from one C implementation to another. The C standard has certain minimum requirements (char is at least 8 bits, short and int are at least 16, long is at least 32, and each type in that list is at least as wide as the previous type), but permits some flexibility. For example, I've seen systems where int is 16, 32, or 64 bits.

char is almost always exactly 8 bits, but it's permitted to be wider. And plain char may be either signed or unsigned.

uint8_t is required to be an unsigned integer type that's exactly 8 bits wide. It's likely to be a typedef for unsigned char, though it might be a typedef for plain char if plain char happens to be unsigned. If there is no predefined 8-bit unsigned type, then uint8_t will not be defined at all.

Similarly, each uintN_t type is an unsigned type that's exactly N bits wide.

In addition, <stdint.h> defines corresponding signed intN_t types, as well as int_fastN_t and int_leastN_t types that are at least the specified width.

The [u]intN_t types are guaranteed to have no padding bits, so the size of each is exactly N bits. The signed intN_t types are required to use a 2's-complement representation.

Although uint32_t might be the same as unsigned int, for example, you shouldn't assume that. Use unsigned int when you need an unsigned integer type that's at least 16 bits wide, and that's the "natural" size for the current system. Use uint32_t when you need an unsigned integer type that's exactly 32 bits wide.

(And no, uint64 or uint64_t is not the same as double; double is a floating-point type.)

Border in shape xml

We can add drawable .xml like below

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
       android:shape="rectangle">


    <stroke
        android:width="1dp"
        android:color="@color/color_C4CDD5"/>

    <corners android:radius="8dp"/>

    <solid
        android:color="@color/color_white"/>

</shape>

How to print the array?

If you want to print the array like you print a 2D list in Python:

#include <stdio.h>

int main()
{
  int i, j;
  int my_array[3][3] = {{10, 23, 42}, {1, 654, 0}, {40652, 22, 0}};
  for(i = 0; i < 3; i++)
  {
      if (i == 0) {
          printf("[");
      }
      printf("[");
      for(j = 0; j < 3; j++)
      {
         printf("%d", my_array[i][j]);
         if (j < 2) {
             printf(", ");
         }
      }
    printf("]");
    if (i == 2) {
        printf("]");
    }

    if (i < 2) {
        printf(", ");
    }
  }
  return 0;
}

Output will be:

[[10, 23, 42], [1, 654, 0], [40652, 22, 0]]

What is Type-safe?

Type-Safe is code that accesses only the memory locations it is authorized to access, and only in well-defined, allowable ways. Type-safe code cannot perform an operation on an object that is invalid for that object. The C# and VB.NET language compilers always produce type-safe code, which is verified to be type-safe during JIT compilation.

Get image dimensions

Using getimagesize function, we can also get these properties of that specific image-

<?php

list($width, $height, $type, $attr) = getimagesize("image_name.jpg");

echo "Width: " .$width. "<br />";
echo "Height: " .$height. "<br />";
echo "Type: " .$type. "<br />";
echo "Attribute: " .$attr. "<br />";

//Using array
$arr = array('h' => $height, 'w' => $width, 't' => $type, 'a' => $attr);
?>


Result like this -

Width: 200
Height: 100
Type: 2
Attribute: width='200' height='100'


Type of image consider like -

1 = GIF
2 = JPG
3 = PNG
4 = SWF
5 = PSD
6 = BMP
7 = TIFF(intel byte order)
8 = TIFF(motorola byte order)
9 = JPC
10 = JP2
11 = JPX
12 = JB2
13 = SWC
14 = IFF
15 = WBMP
16 = XBM

net::ERR_INSECURE_RESPONSE in Chrome

This happens when you update from Chrome 55 to Chrome 56 (56.0.2924.87).
This is an increase in security enforcement.
It doesn't go away by restarting the browser, and it's not a bug.

Mountain View says it's hoping you don't ever encounter the message, because Certificate Authorities are required to stop issuing SHA-1 certificates in 2016. Just in case, Google plans to continue issuing warnings until Chrome completely stops supporting SHA-1 on January 1st, 2017. When that day comes, a website that still uses the function will trigger a fatal network error. (Source: Engadget.com)

If this happens, the most-likely cause is that your (or the website's) SSL-certificate uses SHA1.
SHA1 is broken, and SSL certificates using SHA1 are not secure anymore (it's now been a long time that Chrome showed this to you - now it blocks NET::ERR_CERT_WEAK_SIGNATURE_ALGORITHM).

Another likely cause is that your SSL-certificate expired
Also, you should disable backwards-compatiblity with SSL2 & SSL3 (Poodle Attack).
You should only be using TLS (SSL 3.1+).

To test your domain's SSL-certificate, you can use SSL labs SSL test.

To find out what exactly the issue is: Open the chrome developer console (CTRL + SHIFT + J OR F12) And change to the security tab

Security

Console

Details

For more information:
https://support.google.com/chrome/answer/95617?visit_id=1-636221396724527190-3454695657&p=ui_security_indicator&rd=1

FYI:

SHA-1 has been growing weaker and more insecure everyday for a decade now, which is dangerous considering we tend to trust websites with "https://" in their URLs. Other browsers like Mozilla Firefox and Microsoft Edge also plan to stop supporting it in an effort to encourage website owners to switch to more secure SHA-2 certificates as soon as possible.

If you urgently need to get around it (you need to close all running instances of Chrome first - otherwise it won't work):

chrome --args --ignore-certificate-errors

Please note: don't go online-banking or gmail'ing with those command-line settings active in your Chrome instance.

JSON formatter in C#?

Just use JsonDocument and Utf8JsonWriter. No third-party library required. No target object for deserialization for jsonString required.

using System.IO;
using System.Text;
using System.Text.Json;

// other code ...

public string Prettify(string jsonString)
{
    using var stream = new MemoryStream();
    var document = JsonDocument.Parse(jsonString);
    var writer = new Utf8JsonWriter(stream, new JsonWriterOptions { Indented = true });
    document.WriteTo(writer);
    writer.Flush();
    return Encoding.UTF8.GetString(stream.ToArray());
}

Changing the child element's CSS when the parent is hovered

Not sure if there's terrible reasons to do this or not, but it seems to work with me on the latest version of Chrome/Firefox without any visible performance problems with quite a lot of elements on the page.

*:not(:hover)>.parent-hover-show{
    display:none;
}

But this way, all you need is to apply parent-hover-show to an element and the rest is taken care of, and you can keep whatever default display type you want without it always being "block" or making multiple classes for each type.

sort dict by value python

I also think it is important to note that Python dict object type is a hash table (more on this here), and thus is not capable of being sorted without converting its keys/values to lists. What this allows is dict item retrieval in constant time O(1), no matter the size/number of elements in a dictionary.

Having said that, once you sort its keys - sorted(data.keys()), or values - sorted(data.values()), you can then use that list to access keys/values in design patterns such as these:

for sortedKey in sorted(dictionary):
    print dictionary[sortedKeY] # gives the values sorted by key

for sortedValue in sorted(dictionary.values()):
    print sortedValue # gives the values sorted by value

Hope this helps.

How is malloc() implemented internally?

The sbrksystem call moves the "border" of the data segment. This means it moves a border of an area in which a program may read/write data (letting it grow or shrink, although AFAIK no malloc really gives memory segments back to the kernel with that method). Aside from that, there's also mmap which is used to map files into memory but is also used to allocate memory (if you need to allocate shared memory, mmap is how you do it).

So you have two methods of getting more memory from the kernel: sbrk and mmap. There are various strategies on how to organize the memory that you've got from the kernel.

One naive way is to partition it into zones, often called "buckets", which are dedicated to certain structure sizes. For example, a malloc implementation could create buckets for 16, 64, 256 and 1024 byte structures. If you ask malloc to give you memory of a given size it rounds that number up to the next bucket size and then gives you an element from that bucket. If you need a bigger area malloc could use mmap to allocate directly with the kernel. If the bucket of a certain size is empty malloc could use sbrk to get more space for a new bucket.

There are various malloc designs and there is propably no one true way of implementing malloc as you need to make a compromise between speed, overhead and avoiding fragmentation/space effectiveness. For example, if a bucket runs out of elements an implementation might get an element from a bigger bucket, split it up and add it to the bucket that ran out of elements. This would be quite space efficient but would not be possible with every design. If you just get another bucket via sbrk/mmap that might be faster and even easier, but not as space efficient. Also, the design must of course take into account that "free" needs to make space available to malloc again somehow. You don't just hand out memory without reusing it.

If you're interested, the OpenSER/Kamailio SIP proxy has two malloc implementations (they need their own because they make heavy use of shared memory and the system malloc doesn't support shared memory). See: https://github.com/OpenSIPS/opensips/tree/master/mem

Then you could also have a look at the GNU libc malloc implementation, but that one is very complicated, IIRC.

How to copy a string of std::string type in C++?

You shouldn't use strcpy() to copy a std::string, only use it for C-Style strings.

If you want to copy a to b then just use the = operator.

string a = "text";
string b = "image";
b = a;

Sorting options elements alphabetically using jQuery

Malakgeorge answer is nice an can be easily wrapped into a jQuery function:

$.fn.sortSelectByText = function(){
    this.each(function(){
        var selected = $(this).val(); 
        var opts_list = $(this).find('option');
        opts_list.sort(function(a, b) { return $(a).text() > $(b).text() ? 1 : -1; });
        $(this).html('').append(opts_list);
        $(this).val(selected); 
    })
    return this;        
}

Iframe positioning

Try adding the css style property

position:relative;

to the div tag , it works ,

How would you make a comma-separated string from a list of strings?

If you want to do the shortcut way :) :

','.join([str(word) for word in wordList])

But if you want to show off with logic :) :

wordList = ['USD', 'EUR', 'JPY', 'NZD', 'CHF', 'CAD']
stringText = ''

for word in wordList:
    stringText += word + ','

stringText = stringText[:-2]   # get rid of last comma
print(stringText)

Is there shorthand for returning a default value if None in Python?

You could use the or operator:

return x or "default"

Note that this also returns "default" if x is any falsy value, including an empty list, 0, empty string, or even datetime.time(0) (midnight).

How to reduce a huge excel file

I stumbled upon an interesting reason for a gigantic .xlsx file. Original workbook had 20 sheets or so, was 20 MB I made a new workbook with 1 of the sheets, so it would be more manageable: still 11.5 MB Imagine my surprise to find that the single sheet in the new workbook had 1,041,776 (count 'em!) blank rows. Now it's 13.5 KB

What is offsetHeight, clientHeight, scrollHeight?

My descriptions for the three:

  • offsetHeight: How much of the parent's "relative positioning" space is taken up by the element. (ie. it ignores the element's position: absolute descendents)
  • clientHeight: Same as offset-height, except it excludes the element's own border, margin, and the height of its horizontal scroll-bar (if it has one).
  • scrollHeight: How much space is needed to see all of the element's content/descendents (including position: absolute ones) without scrolling.

Then there is also:

Rotating a Vector in 3D Space

If you want to rotate a vector you should construct what is known as a rotation matrix.

Rotation in 2D

Say you want to rotate a vector or a point by ?, then trigonometry states that the new coordinates are

    x' = x cos ? - y sin ?
    y' = x sin ? + y cos ?

To demo this, let's take the cardinal axes X and Y; when we rotate the X-axis 90° counter-clockwise, we should end up with the X-axis transformed into Y-axis. Consider

    Unit vector along X axis = <1, 0>
    x' = 1 cos 90 - 0 sin 90 = 0
    y' = 1 sin 90 + 0 cos 90 = 1
    New coordinates of the vector, <x', y'> = <0, 1>  ?  Y-axis

When you understand this, creating a matrix to do this becomes simple. A matrix is just a mathematical tool to perform this in a comfortable, generalized manner so that various transformations like rotation, scale and translation (moving) can be combined and performed in a single step, using one common method. From linear algebra, to rotate a point or vector in 2D, the matrix to be built is

    |cos ?   -sin ?| |x| = |x cos ? - y sin ?| = |x'|
    |sin ?    cos ?| |y|   |x sin ? + y cos ?|   |y'|

Rotation in 3D

That works in 2D, while in 3D we need to take in to account the third axis. Rotating a vector around the origin (a point) in 2D simply means rotating it around the Z-axis (a line) in 3D; since we're rotating around Z-axis, its coordinate should be kept constant i.e. 0° (rotation happens on the XY plane in 3D). In 3D rotating around the Z-axis would be

    |cos ?   -sin ?   0| |x|   |x cos ? - y sin ?|   |x'|
    |sin ?    cos ?   0| |y| = |x sin ? + y cos ?| = |y'|
    |  0       0      1| |z|   |        z        |   |z'|

around the Y-axis would be

    | cos ?    0   sin ?| |x|   | x cos ? + z sin ?|   |x'|
    |   0      1       0| |y| = |         y        | = |y'|
    |-sin ?    0   cos ?| |z|   |-x sin ? + z cos ?|   |z'|

around the X-axis would be

    |1     0           0| |x|   |        x        |   |x'|
    |0   cos ?    -sin ?| |y| = |y cos ? - z sin ?| = |y'|
    |0   sin ?     cos ?| |z|   |y sin ? + z cos ?|   |z'|

Note 1: axis around which rotation is done has no sine or cosine elements in the matrix.

Note 2: This method of performing rotations follows the Euler angle rotation system, which is simple to teach and easy to grasp. This works perfectly fine for 2D and for simple 3D cases; but when rotation needs to be performed around all three axes at the same time then Euler angles may not be sufficient due to an inherent deficiency in this system which manifests itself as Gimbal lock. People resort to Quaternions in such situations, which is more advanced than this but doesn't suffer from Gimbal locks when used correctly.

I hope this clarifies basic rotation.

Rotation not Revolution

The aforementioned matrices rotate an object at a distance r = v(x² + y²) from the origin along a circle of radius r; lookup polar coordinates to know why. This rotation will be with respect to the world space origin a.k.a revolution. Usually we need to rotate an object around its own frame/pivot and not around the world's i.e. local origin. This can also be seen as a special case where r = 0. Since not all objects are at the world origin, simply rotating using these matrices will not give the desired result of rotating around the object's own frame. You'd first translate (move) the object to world origin (so that the object's origin would align with the world's, thereby making r = 0), perform the rotation with one (or more) of these matrices and then translate it back again to its previous location. The order in which the transforms are applied matters. Combining multiple transforms together is called concatenation or composition.

Composition

I urge you to read about linear and affine transformations and their composition to perform multiple transformations in one shot, before playing with transformations in code. Without understanding the basic maths behind it, debugging transformations would be a nightmare. I found this lecture video to be a very good resource. Another resource is this tutorial on transformations that aims to be intuitive and illustrates the ideas with animation (caveat: authored by me!).

Rotation around Arbitrary Vector

A product of the aforementioned matrices should be enough if you only need rotations around cardinal axes (X, Y or Z) like in the question posted. However, in many situations you might want to rotate around an arbitrary axis/vector. The Rodrigues' formula (a.k.a. axis-angle formula) is a commonly prescribed solution to this problem. However, resort to it only if you’re stuck with just vectors and matrices. If you're using Quaternions, just build a quaternion with the required vector and angle. Quaternions are a superior alternative for storing and manipulating 3D rotations; it's compact and fast e.g. concatenating two rotations in axis-angle representation is fairly expensive, moderate with matrices but cheap in quaternions. Usually all rotation manipulations are done with quaternions and as the last step converted to matrices when uploading to the rendering pipeline. See Understanding Quaternions for a decent primer on quaternions.

Permutation of array

Visual representation of the 3-item recursive solution: http://www.docdroid.net/ea0s/generatepermutations.pdf.html

Breakdown:

  1. For a two-item array, there are two permutations:
    • The original array, and
    • The two elements swapped
  2. For a three-item array, there are six permutations:
    • The permutations of the bottom two elements, then
    • Swap 1st and 2nd items, and the permutations of the bottom two element
    • Swap 1st and 3rd items, and the permutations of the bottom two elements.
    • Essentially, each of the items gets its chance at the first slot

How should the ViewModel close the form?

Here's what I initially did, which does work, however it seems rather long-winded and ugly (global static anything is never good)

1: App.xaml.cs

public partial class App : Application
{
    // create a new global custom WPF Command
    public static readonly RoutedUICommand LoggedIn = new RoutedUICommand();
}

2: LoginForm.xaml

// bind the global command to a local eventhandler
<CommandBinding Command="client:App.LoggedIn" Executed="OnLoggedIn" />

3: LoginForm.xaml.cs

// implement the local eventhandler in codebehind
private void OnLoggedIn( object sender, ExecutedRoutedEventArgs e )
{
    DialogResult = true;
    Close();
}

4: LoginFormViewModel.cs

// fire the global command from the viewmodel
private void OnRemoteServerReturnedSuccess()
{
    App.LoggedIn.Execute(this, null);
}

I later on then removed all this code, and just had the LoginFormViewModel call the Close method on it's view. It ended up being much nicer and easier to follow. IMHO the point of patterns is to give people an easier way to understand what your app is doing, and in this case, MVVM was making it far harder to understand than if I hadn't used it, and was now an anti-pattern.

Proper way to initialize C++ structs

You need to initialize whatever members you have in your struct, e.g.:

struct MyStruct {
  private:
    int someInt_;
    float someFloat_;

  public:
    MyStruct(): someInt_(0), someFloat_(1.0) {} // Initializer list will set appropriate values

};

Folder structure for a Node.js project

This is indirect answer, on the folder structure itself, very related.

A few years ago I had same question, took a folder structure but had to do a lot directory moving later on, because the folder was meant for a different purpose than that I have read on internet, that is, what a particular folder does has different meanings for different people on some folders.

Now, having done multiple projects, in addition to explanation in all other answers, on the folder structure itself, I would strongly suggest to follow the structure of Node.js itself, which can be seen at: https://github.com/nodejs/node. It has great detail on all, say linters and others, what file and folder structure they have and where. Some folders have a README that explains what is in that folder.

Starting in above structure is good because some day a new requirement comes in and but you will have a scope to improve as it is already followed by Node.js itself which is maintained over many years now.

Hope this helps.

Get operating system info

If you want very few info like a class in your html for common browsers for instance, you could use:

function get_browser()
{
    $browser = '';
    $ua = strtolower($_SERVER['HTTP_USER_AGENT']);
    if (preg_match('~(?:msie ?|trident.+?; ?rv: ?)(\d+)~', $ua, $matches)) $browser = 'ie ie'.$matches[1];
    elseif (preg_match('~(safari|chrome|firefox)~', $ua, $matches)) $browser = $matches[1];

    return $browser;
}

which will return 'safari' or 'firefox' or 'chrome', or 'ie ie8', 'ie ie9', 'ie ie10', 'ie ie11'.

Cast received object to a List<object> or IEnumerable<object>

Problem is, you're trying to upcast to a richer object. You simply need to add the items to a new list:

if (myObject is IEnumerable)
{
   List<object> list = new List<object>();
   var enumerator = ((IEnumerable) myObject).GetEnumerator();
   while (enumerator.MoveNext())
   {
      list.Add(enumerator.Current);
   }
}

Pass a simple string from controller to a view MVC3

Just define your action method like this

public string ThemePath()

and simply return the string itself.

What is JavaScript garbage collection?

Reference types do not store the object directly into the variable to which it is assigned, so the object variable in the example below, doesn’t actually contain the object instance. Instead, it holds a pointer (or reference) to the location in memory, where the object exists.

var object = new Object();

if you assign one reference typed variable to another, each variable gets a copy of the pointer, and both still reference to the same object in memory.

var object1 = new Object();
var object2 = object1;

Two variables pointing to one object

JavaScript is a garbage-collected language, so you don’t really need to worry about memory allocations when you use reference types. However, it’s best to dereference objects that you no longer need so that the garbage collector can free up that memory. The best way to do this is to set the object variable to null.

var object1 = new Object();
// do something
object1 = null; // dereference

Dereferencing objects is especially important in very large applications that use millions of objects.

from The Principles of Object-Oriented JavaScript - NICHOLAS C. ZAKAS

Converting byte array to string in javascript

String to byte array: "FooBar".split('').map(c => c.charCodeAt(0));

Byte array to string: [102, 111, 111, 98, 97, 114].map(c => String.fromCharCode(c)).join('');

allowing only alphabets in text box using java script

From kosare comments, i have create an demo http://jsbin.com/aTUMeMAV/2/

HTML

      <form name="f" onsubmit="return onlyAlphabets()">
         <input type="text" name="nm">
         <div id="notification"></div>
         <input type="submit">
      </form>

javascript

  function onlyAlphabets() {

  var regex = /^[a-zA-Z]*$/;
  if (regex.test(document.f.nm.value)) {

      //document.getElementById("notification").innerHTML = "Watching.. Everything is Alphabet now";
      return true;
  } else {
      document.getElementById("notification").innerHTML = "Alphabets Only";
      return false;
  }


}

SSIS Excel Import Forcing Incorrect Column Type

This worked for me. Select the problematic column in Excel - highlight the whole column. Change the format to "Text". Save the Excel file.

In your SSIS package, go to the Data Flow pane for your import. Double click the Excel Source node. It should warn you that the types have changed and ask you if you want to remap them. Click Yes. Executing should now work and bring in all values.

Note: I'm using Excel 2013 and Visual Studio 2015, but I assume these instructions would work for earlier versions too.

How to "perfectly" override a dict?

You can write an object that behaves like a dict quite easily with ABCs (Abstract Base Classes) from the collections.abc module. It even tells you if you missed a method, so below is the minimal version that shuts the ABC up.

from collections.abc import MutableMapping


class TransformedDict(MutableMapping):
    """A dictionary that applies an arbitrary key-altering
       function before accessing the keys"""

    def __init__(self, *args, **kwargs):
        self.store = dict()
        self.update(dict(*args, **kwargs))  # use the free update to set keys

    def __getitem__(self, key):
        return self.store[self._keytransform(key)]

    def __setitem__(self, key, value):
        self.store[self._keytransform(key)] = value

    def __delitem__(self, key):
        del self.store[self._keytransform(key)]

    def __iter__(self):
        return iter(self.store)
    
    def __len__(self):
        return len(self.store)

    def _keytransform(self, key):
        return key

You get a few free methods from the ABC:

class MyTransformedDict(TransformedDict):

    def _keytransform(self, key):
        return key.lower()


s = MyTransformedDict([('Test', 'test')])

assert s.get('TEST') is s['test']   # free get
assert 'TeSt' in s                  # free __contains__
                                    # free setdefault, __eq__, and so on

import pickle
# works too since we just use a normal dict
assert pickle.loads(pickle.dumps(s)) == s

I wouldn't subclass dict (or other builtins) directly. It often makes no sense, because what you actually want to do is implement the interface of a dict. And that is exactly what ABCs are for.

Is an empty href valid?

Whilst W3's validator may not complain about an empty href attribute, the current HTML5 Working Draft specifies:

The href attribute on a and area elements must have a value that is a valid URL potentially surrounded by spaces.

A valid URL is a URL which complies with the URL Standard. Now the URL Standard is a bit confusing to get your head around, however nowhere does it state that a URL can be an empty string.

...which means that an empty string is not a valid URL.

The HTML5 Working Draft goes on, however, to state:

Note: The href attribute on a and area elements is not required; when those elements do not have href attributes they do not create hyperlinks.

This means we can simply omit the href attribute altogether:

<a class="arrow"></a>

If your intention is that these href-less a elements should still require keyboard interraction, you'll have to go down the normal route of assigning a role and tabindex alongside your usual click/keydown handlers:

<a class="arrow" role="button" tab-index="0"></a>

Send private messages to friends

You cannot. Facebook API has read_mailbox but no write_mailbox extended permission. I'm guessing this is done to prevent spammy apps from flooding friend's inboxes.

wp_nav_menu change sub-menu class name?

There is no option for this, but you can extend the 'walker' object that WordPress uses to create the menu HTML. Only one method needs to be overridden:

class My_Walker_Nav_Menu extends Walker_Nav_Menu {
  function start_lvl(&$output, $depth) {
    $indent = str_repeat("\t", $depth);
    $output .= "\n$indent<ul class=\"my-sub-menu\">\n";
  }
}

Then you just pass an instance of your walker as an argument to wp_nav_menu like so:

'walker' => new My_Walker_Nav_Menu()

How to close a Java Swing application from the code

If I understand you correctly you want to close the application even if the user did not click on the close button. You will need to register WindowEvents maybe with addWindowListener() or enableEvents() whichever suits your needs better.

You can then invoke the event with a call to processWindowEvent(). Here is a sample code that will create a JFrame, wait 5 seconds and close the JFrame without user interaction.

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

public class ClosingFrame extends JFrame implements WindowListener{

public ClosingFrame(){
    super("A Frame");
    setSize(400, 400);
            //in case the user closes the window
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            setVisible(true);
            //enables Window Events on this Component
            this.addWindowListener(this);

            //start a timer
    Thread t = new Timer();
            t.start();
    }

public void windowOpened(WindowEvent e){}
public void windowClosing(WindowEvent e){}

    //the event that we are interested in
public void windowClosed(WindowEvent e){
    System.exit(0);
}

public void windowIconified(WindowEvent e){}
public void windowDeiconified(WindowEvent e){}
public void windowActivated(WindowEvent e){}
public void windowDeactivated(WindowEvent e){}

    //a simple timer 
    class Timer extends Thread{
           int time = 10;
           public void run(){
     while(time-- > 0){
       System.out.println("Still Waiting:" + time);
               try{
                 sleep(500);                     
               }catch(InterruptedException e){}
             }
             System.out.println("About to close");
    //close the frame
            ClosingFrame.this.processWindowEvent(
                 new WindowEvent(
                       ClosingFrame.this, WindowEvent.WINDOW_CLOSED));
           }
    }

    //instantiate the Frame
public static void main(String args[]){
          new ClosingFrame();
    }

}

As you can see, the processWindowEvent() method causes the WindowClosed event to be fired where you have an oportunity to do some clean up code if you require before closing the application.

IF a cell contains a string

=IFS(COUNTIF(A1,"*cats*"),"cats",COUNTIF(A1,"*22*"),"22",TRUE,"none")

java.math.BigInteger cannot be cast to java.lang.Long

Imagine d.getId is a Long, then wrap like this:

BigInteger l  = BigInteger.valueOf(d.getId());

Exit a while loop in VBS/VBA

I know this is old as dirt but it ranked pretty high in google.

The problem with the solution maddy implemented (in response to rahul) to maintain the use of a While...Wend loop has some drawbacks

In the example given

num = 0
While num < 10
  If status = "Fail" Then
    num = 10
  End If
  num = num + 1
Wend

After status = "Fail" num will actually equal 11. The loop didn't end on the fail condition, it ends on the next test. All of the code after the check still processed and your counter is not what you might have expected it to be.

Now depending on what you are all doing in your loop it may not matter, but then again if your code looked something more like:

num = 0
While num < 10
  If folder = "System32" Then
    num = 10
  End If
  RecursiveDeleteFunction folder
  num = num + 1
Wend

Using Do While or Do Until allows you to stop execution of the loop using Exit Do instead of using trickery with your loop condition to maintain the While ... Wend syntax. I would recommend using that instead.

How to copy folders to docker image from Dockerfile?

As mentioned in your ticket:

You have COPY files/* /test/ which expands to COPY files/dir files/file1 files/file2 files/file /test/.
If you split this up into individual COPY commands (e.g. COPY files/dir /test/) you'll see that (for better or worse) COPY will copy the contents of each arg dir into the destination directory. Not the arg dir itself, but the contents.

I'm not thrilled with that fact that COPY doesn't preserve the top-level dir but its been that way for a while now.

so in the name of preserving a backward compatibility, it is not possible to COPY/ADD a directory structure.

The only workaround would be a series of RUN mkdir -p /x/y/z to build the target directory structure, followed by a series of docker ADD (one for each folder to fill).
(ADD, not COPY, as per comments)

How to redirect page after click on Ok button on sweet alert?

To specify a callback function, you have to use an object as the first argument, and the callback function as the second argument.

echo '<script>
    setTimeout(function() {
        swal({
            title: "Wow!",
            text: "Message!",
            type: "success"
        }, function() {
            window.location = "redirectURL";
        });
    }, 1000);
</script>';

Understanding __get__ and __set__ and Python descriptors

The descriptor is how Python's property type is implemented. A descriptor simply implements __get__, __set__, etc. and is then added to another class in its definition (as you did above with the Temperature class). For example:

temp=Temperature()
temp.celsius #calls celsius.__get__

Accessing the property you assigned the descriptor to (celsius in the above example) calls the appropriate descriptor method.

instance in __get__ is the instance of the class (so above, __get__ would receive temp, while owner is the class with the descriptor (so it would be Temperature).

You need to use a descriptor class to encapsulate the logic that powers it. That way, if the descriptor is used to cache some expensive operation (for example), it could store the value on itself and not its class.

An article about descriptors can be found here.

EDIT: As jchl pointed out in the comments, if you simply try Temperature.celsius, instance will be None.

javascript pushing element at the beginning of an array

Use .unshift() to add to the beginning of an array.

TheArray.unshift(TheNewObject);

See MDN for doc on unshift() and here for doc on other array methods.

FYI, just like there's .push() and .pop() for the end of the array, there's .shift() and .unshift() for the beginning of the array.

How can I remove jenkins completely from linux

If your jenkins is running as service instead of process you should stop it first using

sudo service jenkins stop

After stopping it you can follow the normal flow of removing it using commands respective to your linux flavour

For centos it will be

sudo yum remove jenkins

For ubuntu it will

sudo apt-get remove --purge jenkins

I hope this will solve your issue.

how to parse xml to java object?

JAXB is an ideal solution. But you do not necessarily need xsd and xjc for that. More often than not you don't have an xsd but you know what your xml is. Simply analyze your xml, e.g.,

<customer id="100">
    <age>29</age>
    <name>mkyong</name>
</customer>

Create necessary model class(es):

@XmlRootElement
public class Customer {

    String name;
    int age;
    int id;

    public String getName() {
        return name;
    }

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

    public int getAge() {
        return age;
    }

    @XmlElement
    public void setAge(int age) {
        this.age = age;
    }

    public int getId() {
        return id;
    }

    @XmlAttribute
    public void setId(int id) {
        this.id = id;
    }

}

Try to unmarshal:

JAXBContext jaxbContext = JAXBContext.newInstance(Customer.class);
Unmarshaller jaxbUnmarshaller = jaxbContext.createUnmarshaller();
Customer customer = (Customer) jaxbUnmarshaller.unmarshal(new File("C:\\file.xml"));

Check results, fix bugs!

Plotting two variables as lines using ggplot2 on the same graph

The general approach is to convert the data to long format (using melt() from package reshape or reshape2) or gather()/pivot_longer() from the tidyr package:

library("reshape2")
library("ggplot2")

test_data_long <- melt(test_data, id="date")  # convert to long format

ggplot(data=test_data_long,
       aes(x=date, y=value, colour=variable)) +
       geom_line()

ggplot2 output

Also see this question on reshaping data from wide to long.

How to get an element's top position relative to the browser's viewport?

I am assuming an element having an id of btn1 exists in the web page, and also that jQuery is included. This has worked across all modern browsers of Chrome, FireFox, IE >=9 and Edge. jQuery is only being used to determine the position relative to document.

var screenRelativeTop =  $("#btn1").offset().top - (window.scrollY || 
                                            window.pageYOffset || document.body.scrollTop);

var screenRelativeLeft =  $("#btn1").offset().left - (window.scrollX ||
                                           window.pageXOffset || document.body.scrollLeft);

Convert string to date then format the date

Tested this code

java.text.DateFormat formatter = new java.text.SimpleDateFormat("MM-dd-yyyy");
java.util.Date newDate = new java.util.Date();
System.out.println(formatter.format(newDate ));

http://download.oracle.com/javase/1,5.0/docs/api/java/text/SimpleDateFormat.html

Switch statement fallthrough in C#?

You can 'goto case label' http://www.blackwasp.co.uk/CSharpGoto.aspx

The goto statement is a simple command that unconditionally transfers the control of the program to another statement. The command is often criticised with some developers advocating its removal from all high-level programming languages because it can lead to spaghetti code. This occurs when there are so many goto statements or similar jump statements that the code becomes difficult to read and maintain. However, there are programmers who point out that the goto statement, when used carefully, provides an elegant solution to some problems...

PHP: How to check if a date is today, yesterday or tomorrow

This worked for me, where I wanted to display keyword "today" or "yesterday" only if date was today and previous day otherwise display date in d-M-Y format

<?php
function findDayDiff($date){
   $param_date=date('d-m-Y',strtotime($date);
   $response  = $param_date;
   if($param_date==date('d-m-Y',strtotime("now"))){
       $response = 'Today';
   }else if($param_date==date('d-m-Y',strtotime("-1 days"))){
       $response = 'Yesterday'; 
   }
   return $response;
}
?>

How can I sort a List alphabetically?

Better late than never! Here is how we can do it(for learning purpose only)-

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

class SoftDrink {
    String name;
    String color;
    int volume; 

    SoftDrink (String name, String color, int volume) {
        this.name = name;
        this.color = color;
        this.volume = volume;
    }
}

public class ListItemComparision {
    public static void main (String...arg) {
        List<SoftDrink> softDrinkList = new ArrayList<SoftDrink>() ;
        softDrinkList .add(new SoftDrink("Faygo", "ColorOne", 4));
        softDrinkList .add(new SoftDrink("Fanta",  "ColorTwo", 3));
        softDrinkList .add(new SoftDrink("Frooti", "ColorThree", 2));       
        softDrinkList .add(new SoftDrink("Freshie", "ColorFour", 1));

        Collections.sort(softDrinkList, new Comparator() {
            @Override
            public int compare(Object softDrinkOne, Object softDrinkTwo) {
                //use instanceof to verify the references are indeed of the type in question
                return ((SoftDrink)softDrinkOne).name
                        .compareTo(((SoftDrink)softDrinkTwo).name);
            }
        }); 
        for (SoftDrink sd : softDrinkList) {
            System.out.println(sd.name + " - " + sd.color + " - " + sd.volume);
        }
        Collections.sort(softDrinkList, new Comparator() {
            @Override
            public int compare(Object softDrinkOne, Object softDrinkTwo) {
                //comparision for primitive int uses compareTo of the wrapper Integer
                return(new Integer(((SoftDrink)softDrinkOne).volume))
                        .compareTo(((SoftDrink)softDrinkTwo).volume);
            }
        });

        for (SoftDrink sd : softDrinkList) {
            System.out.println(sd.volume + " - " + sd.color + " - " + sd.name);
        }   
    }
}

Fork() function in C

System call fork() is used to create processes. It takes no arguments and returns a process ID. The purpose of fork() is to create a new process, which becomes the child process of the caller. After a new child process is created, both processes will execute the next instruction following the fork() system call. Therefore, we have to distinguish the parent from the child. This can be done by testing the returned value of fork()

Fork is a system call and you shouldnt think of it as a normal C function. When a fork() occurs you effectively create two new processes with their own address space.Variable that are initialized before the fork() call store the same values in both the address space. However values modified within the address space of either of the process remain unaffected in other process one of which is parent and the other is child. So if,

pid=fork();

If in the subsequent blocks of code you check the value of pid.Both processes run for the entire length of your code. So how do we distinguish them. Again Fork is a system call and here is difference.Inside the newly created child process pid will store 0 while in the parent process it would store a positive value.A negative value inside pid indicates a fork error.

When we test the value of pid to find whether it is equal to zero or greater than it we are effectively finding out whether we are in the child process or the parent process.

Read more about Fork

Skip first couple of lines while reading lines in Python file

Here are the timeit results for the top 2 answers. Note that "file.txt" is a text file containing 100,000+ lines of random string with a file size of 1MB+.

Using itertools:

import itertools
from timeit import timeit

timeit("""with open("file.txt", "r") as fo:
    for line in itertools.islice(fo, 90000, None):
        line.strip()""", number=100)

>>> 1.604976346003241

Using two for loops:

from timeit import timeit

timeit("""with open("file.txt", "r") as fo:
    for i in range(90000):
        next(fo)
    for j in fo:
        j.strip()""", number=100)

>>> 2.427317383000627

clearly the itertools method is more efficient when dealing with large files.

CronJob not running

It might also be a timezone problem.

Cron uses the local time.

Run the command timedatectl to see the machine time and make sure that your crontab is in this same timezone.

Converting NSString to NSDictionary / JSON

Use this code where str is your JSON string:

NSError *err = nil;
NSArray *arr = 
 [NSJSONSerialization JSONObjectWithData:[str dataUsingEncoding:NSUTF8StringEncoding] 
                                 options:NSJSONReadingMutableContainers 
                                   error:&err];
// access the dictionaries
NSMutableDictionary *dict = arr[0];
for (NSMutableDictionary *dictionary in arr) {
  // do something using dictionary
}

Eclipse error: "Editor does not contain a main type"

Did you import the packages for the file reading stuff.

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.InputStreamReader;

also here

cfiltering(numberOfUsers, numberOfMovies);

Are you trying to create an object or calling a method?

also another thing:

user_movie_matrix[userNo][movieNo]=rating;

you are assigning a value to a member of an instance as if it was a static variable also remove the Th in

private int user_movie_matrix[][];Th

Hope this helps.

Counting the Number of keywords in a dictionary in python

If the question is about counting the number of keywords then would recommend something like

def countoccurrences(store, value):
    try:
        store[value] = store[value] + 1
    except KeyError as e:
        store[value] = 1
    return

in the main function have something that loops through the data and pass the values to countoccurrences function

if __name__ == "__main__":
    store = {}
    list = ('a', 'a', 'b', 'c', 'c')
    for data in list:
        countoccurrences(store, data)
    for k, v in store.iteritems():
        print "Key " + k + " has occurred "  + str(v) + " times"

The code outputs

Key a has occurred 2 times
Key c has occurred 2 times
Key b has occurred 1 times

Safe Area of Xcode 9

Safe Area is a layout guide (Safe Area Layout Guide).
The layout guide representing the portion of your view that is unobscured by bars and other content. In iOS 11+, Apple is deprecating the top and bottom layout guides and replacing them with a single safe area layout guide.

When the view is visible onscreen, this guide reflects the portion of the view that is not covered by other content. The safe area of a view reflects the area covered by navigation bars, tab bars, toolbars, and other ancestors that obscure a view controller's view. (In tvOS, the safe area incorporates the screen's bezel, as defined by the overscanCompensationInsets property of UIScreen.) It also covers any additional space defined by the view controller's additionalSafeAreaInsets property. If the view is not currently installed in a view hierarchy, or is not yet visible onscreen, the layout guide always matches the edges of the view.

For the view controller's root view, the safe area in this property represents the entire portion of the view controller's content that is obscured, and any additional insets that you specified. For other views in the view hierarchy, the safe area reflects only the portion of that view that is obscured. For example, if a view is entirely within the safe area of its view controller's root view, the edge insets in this property are 0.

According to Apple, Xcode 9 - Release note
Interface Builder uses UIView.safeAreaLayoutGuide as a replacement for the deprecated Top and Bottom layout guides in UIViewController. To use the new safe area, select Safe Area Layout Guides in the File inspector for the view controller, and then add constraints between your content and the new safe area anchors. This prevents your content from being obscured by top and bottom bars, and by the overscan region on tvOS. Constraints to the safe area are converted to Top and Bottom when deploying to earlier versions of iOS.

enter image description here


Here is simple reference as a comparison (to make similar visual effect) between existing (Top & Bottom) Layout Guide and Safe Area Layout Guide.

Safe Area Layout: enter image description here

AutoLayout

enter image description here


How to work with Safe Area Layout?

Follow these steps to find solution:

  • Enable 'Safe Area Layout', if not enabled.
  • Remove 'all constraint' if they shows connection with with Super view and re-attach all with safe layout anchor. OR Double click on a constraint and edit connection from super view to SafeArea anchor

Here is sample snapshot, how to enable safe area layout and edit constraint.

enter image description here

Here is result of above changes

enter image description here


Layout Design with SafeArea
When designing for iPhone X, you must ensure that layouts fill the screen and aren't obscured by the device's rounded corners, sensor housing, or the indicator for accessing the Home screen.

enter image description here

Most apps that use standard, system-provided UI elements like navigation bars, tables, and collections automatically adapt to the device's new form factor. Background materials extend to the edges of the display and UI elements are appropriately inset and positioned.

enter image description here

For apps with custom layouts, supporting iPhone X should also be relatively easy, especially if your app uses Auto Layout and adheres to safe area and margin layout guides.

enter image description here


Here is sample code (Ref from: Safe Area Layout Guide):
If you create your constraints in code use the safeAreaLayoutGuide property of UIView to get the relevant layout anchors. Let’s recreate the above Interface Builder example in code to see how it looks:

Assuming we have the green view as a property in our view controller:

private let greenView = UIView()

We might have a function to set up the views and constraints called from viewDidLoad:

private func setupView() {
  greenView.translatesAutoresizingMaskIntoConstraints = false
  greenView.backgroundColor = .green
  view.addSubview(greenView)
}

Create the leading and trailing margin constraints as always using the layoutMarginsGuide of the root view:

 let margins = view.layoutMarginsGuide
    NSLayoutConstraint.activate([
      greenView.leadingAnchor.constraint(equalTo: margins.leadingAnchor),
      greenView.trailingAnchor.constraint(equalTo: margins.trailingAnchor)
 ])

Now unless you are targeting iOS 11 only you will need to wrap the safe area layout guide constraints with #available and fall back to top and bottom layout guides for earlier iOS versions:

if #available(iOS 11, *) {
  let guide = view.safeAreaLayoutGuide
  NSLayoutConstraint.activate([
   greenView.topAnchor.constraintEqualToSystemSpacingBelow(guide.topAnchor, multiplier: 1.0),
   guide.bottomAnchor.constraintEqualToSystemSpacingBelow(greenView.bottomAnchor, multiplier: 1.0)
   ])

} else {
   let standardSpacing: CGFloat = 8.0
   NSLayoutConstraint.activate([
   greenView.topAnchor.constraint(equalTo: topLayoutGuide.bottomAnchor, constant: standardSpacing),
   bottomLayoutGuide.topAnchor.constraint(equalTo: greenView.bottomAnchor, constant: standardSpacing)
   ])
}


Result:

enter image description here


Following UIView extension, make it easy for you to work with SafeAreaLayout programatically.

extension UIView {

  // Top Anchor
  var safeAreaTopAnchor: NSLayoutYAxisAnchor {
    if #available(iOS 11.0, *) {
      return self.safeAreaLayoutGuide.topAnchor
    } else {
      return self.topAnchor
    }
  }

  // Bottom Anchor
  var safeAreaBottomAnchor: NSLayoutYAxisAnchor {
    if #available(iOS 11.0, *) {
      return self.safeAreaLayoutGuide.bottomAnchor
    } else {
      return self.bottomAnchor
    }
  }

  // Left Anchor
  var safeAreaLeftAnchor: NSLayoutXAxisAnchor {
    if #available(iOS 11.0, *) {
      return self.safeAreaLayoutGuide.leftAnchor
    } else {
      return self.leftAnchor
    }
  }

  // Right Anchor
  var safeAreaRightAnchor: NSLayoutXAxisAnchor {
    if #available(iOS 11.0, *) {
      return self.safeAreaLayoutGuide.rightAnchor
    } else {
      return self.rightAnchor
    }
  }

}

Here is sample code in Objective-C:


Here is Apple Developer Official Documentation for Safe Area Layout Guide


Safe Area is required to handle user interface design for iPhone-X. Here is basic guideline for How to design user interface for iPhone-X using Safe Area Layout

Pandas: change data type of Series to String

Personally none of the above worked for me. What did:

new_str = [str(x) for x in old_obj][0]

Polynomial time and exponential time

Below are some common Big-O functions while analyzing algorithms.

  • O(1) - constant time
  • O(log(n)) - logarithmic time
  • O((log(n))c) - polylogarithmic time
  • O(n) - linear time
  • O(n2) - quadratic time
  • O(nc) - polynomial time
  • O(cn) - exponential time
  • O(n!) - factorial time

(n = size of input, c = some constant)

Here is the model graph representing Big-O complexity of some functions

graph model

cheers :-)

graph credits http://bigocheatsheet.com/

Missing `server' JVM (Java\jre7\bin\server\jvm.dll.)

To Fix The "Missing "server" JVM at C:\Program Files\Java\jre7\bin\server\jvm­­.dll, please install or use the JRE or JDK that contains these missing components.

Follow these steps:

Go to oracle.com and install Java JRE7 (Check if Java 6 is not installed already)

After that, go to C:/Program files/java/jre7/bin

Here, create an folder called Server

Now go into the C:/Program files/java/jre7/bin/client folder

Copy all the data in this folder into the new C:/Program files/java/jre7/bin/Server folder

How to display HTML in TextView?

Use below code to get the solution:

textView.setText(fromHtml("<Your Html Text>"))

Utitilty Method

public static Spanned fromHtml(String text)
{
    Spanned result;
    if (Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.N) {
        result = Html.fromHtml(text, Html.FROM_HTML_MODE_LEGACY);
    } else {
        result = Html.fromHtml(text);
    }
    return result;
}

LabelEncoder: TypeError: '>' not supported between instances of 'float' and 'str'

As string data types have variable length, it is by default stored as object type. I faced this problem after treating missing values too. Converting all those columns to type 'category' before label encoding worked in my case.

df[cat]=df[cat].astype('category')

And then check df.dtypes and perform label encoding.

How to make a background 20% transparent on Android

Use a color with an alpha value like #33------, and set it as background of your editText using the XML attribute android:background=" ".

  1. 0% (transparent) -> #00 in hex
  2. 20% -> #33
  3. 50% -> #80
  4. 75% -> #C0
  5. 100% (opaque) -> #FF

255 * 0.2 = 51 ? in hex 33

PHP date add 5 year to current date

Its very very easy with Carbon. $date = "2016-02-16"; // Or Your date $newDate = Carbon::createFromFormat('Y-m-d', $date)->addYear(1);

Get all mysql selected rows into an array

$name=array(); 
while($result=mysql_fetch_array($res)) {
    $name[]=array('Id'=>$result['id']); 
    // here you want to fetch all 
    // records from table like this. 
    // then you should get the array 
    // from all rows into one array 
}

Best way to check if column returns a null value (from database to .net application)

Just check for

if(table.rows[0][0] == null)
{
     //Whatever I want to do
}

or you could

if(t.Rows[0].IsNull(0))
{
     //Whatever I want to do
}

How to get the first 2 letters of a string in Python?

In general, you can the characters of a string from i until j with string[i:j]. string[:2] is shorthand for string[0:2]. This works for arrays as well.

Learn about python's slice notation at the official tutorial

jQuery: Scroll down page a set increment (in pixels) on click?

var y = $(window).scrollTop();  //your current y position on the page
$(window).scrollTop(y+150);

How do I compute the intersection point of two lines?

img And You can use this kode

class Nokta:
def __init__(self,x,y):
    self.x=x
    self.y=y             
class Dogru:
def __init__(self,a,b):
    self.a=a
    self.b=b        

def Kesisim(self,Dogru_b):
    x1= self.a.x
    x2=self.b.x
    x3=Dogru_b.a.x
    x4=Dogru_b.b.x
    y1= self.a.y
    y2=self.b.y
    y3=Dogru_b.a.y
    y4=Dogru_b.b.y                          
    #Notlardaki denklemleri kullandim
    pay1=((x4 - x3) * (y1 - y3) - (y4 - y3) * (x1 - x3))      
    pay2=((x2-x1) * (y1 - y3) - (y2 - y1) * (x1 - x3))
    payda=((y4 - y3) *(x2-x1)-(x4 - x3)*(y2 - y1))        

    if pay1==0 and pay2==0 and payda==0:
        print("DOGRULAR BIRBIRINE ÇAKISIKTIR")

    elif payda==0:               
        print("DOGRULAR BIRBIRNE PARALELDIR")        
    else:                               
        ua=pay1/payda if payda else 0                   
        ub=pay2/payda  if payda else 0  
        #x ve y buldum 
        x=x1+ua*(x2-x1) 
        y=y1+ua*(y2-y1)
        print("DOGRULAR {},{} NOKTASINDA KESISTI".format(x,y))

React Router v4 - How to get current route?

In the 5.1 release of react-router there is a hook called useLocation, which returns the current location object. This might useful any time you need to know the current URL.

import { useLocation } from 'react-router-dom'

function HeaderView() {
  const location = useLocation();
  console.log(location.pathname);
  return <span>Path : {location.pathname}</span>
}

how to make a html iframe 100% width and height?

Answering this just in case if someone else like me stumbles upon this post among many that advise use of JavaScripts for changing iframe height to 100%.

I strongly recommend that you see and try this option specified at How do you give iframe 100% height before resorting to a JavaScript based option. The referenced solution works perfectly for me in all of the testing I have done so far. Hope this helps someone.

How do I tell a Python script to use a particular version

While working with different versions of Python on Windows,

I am using this method to switch between versions.

I think it is better than messing with shebangs and virtualenvs

1) install python versions you desire

2) go to Environment Variables > PATH

(i assume that paths of python versions are already added to Env.Vars.>PATH)

3) suppress the paths of all python versions you dont want to use

(dont delete the paths, just add a suffix like "_sup")

4) call python from terminal

(so Windows will skip the wrong paths you changed, and will find the python.exe at the path you did not suppressed, and will use this version after on)

5) switch between versions by playing with suffixes

How to delete/truncate tables from Hadoop-Hive?

Use the following to delete all the tables in a linux environment.

hive -e 'show tables' | xargs -I '{}' hive -e 'drop table {}'

What's the difference between <b> and <strong>, <i> and <em>?

We use the <strong> tag for text which has high priority for SEO purposes like product name, company name etc, while <b> simple makes it bold.

Similarly, we use <em> for text which has high priority for SEO, while <i> to make the text simply italic.

jQuery Scroll to bottom of page/iframe

For example:

$('html, body').scrollTop($(document).height());

Set CSS property in Javascript?

It is important to understand that the code bellow does not change the stylesheet, but instead changes the DOM:

document.getElementById("p2").style.color = "blue";

The DOM stores a computed value of the stylesheet element properties, and when you dynamically change an elements style using Javascript you are changing the DOM. This is important to note, and understand because the way you write your code can affect your dynamics. If you try to obtain values that were not written directly into the element itself, like so...

let elem = document.getElementById('some-element');
let propertyValue = elem.style['some-property'];

...you will return an undefined value that will be stored in the code example's 'propertyValue' variable. If you are working with getting and setting properties that were written inside a CSS style-sheet and you want a SINGLE FUNCTION that gets, as well as sets style-property-values in this situation, which is a very common situation to be in, then you have got to use JQuery.

$(selector).css(property,value)

The only downside is you got to know JQuery, but this is honestly one of the very many good reasons that every Javascript Developer should learn JQuery. If you want to get a CSS property that was computed from a style-sheet in pure JavaScript then you need to use.

function getCssProp(){
  let ele = document.getElementById("test");
  let cssProp = window.getComputedStyle(ele,null).getPropertyValue("width");
}

The downside to this method is that the getComputedValue method only gets, it does not set. Mozilla's Take on Computed Values This link goes more into depth about what I have addressed here. Hope This Helps Someone!!!

How to free memory in Java?

*"I personally rely on nulling variables as a placeholder for future proper deletion. For example, I take the time to nullify all elements of an array before actually deleting (making null) the array itself."

This is unnecessary. The way the Java GC works is it finds objects that have no reference to them, so if I have an Object x with a reference (=variable) a that points to it, the GC won't delete it, because there is a reference to that object:

a -> x

If you null a than this happens:

a -> null
     x

So now x doesn't have a reference pointing to it and will be deleted. The same thing happens when you set a to reference to a different object than x.

So if you have an array arr that references to objects x, y and z and a variable a that references to the array it looks like that:

a -> arr -> x
         -> y
         -> z

If you null a than this happens:

a -> null
     arr -> x
         -> y
         -> z

So the GC finds arr as having no reference set to it and deletes it, which gives you this structure:

a -> null
     x
     y
     z

Now the GC finds x, y and z and deletes them aswell. Nulling each reference in the array won't make anything better, it will just use up CPU time and space in the code (that said, it won't hurt further than that. The GC will still be able to perform the way it should).

How do you use the Immediate Window in Visual Studio?

The Immediate window is used to debug and evaluate expressions, execute statements, print variable values, and so forth. It allows you to enter expressions to be evaluated or executed by the development language during debugging.

To display Immediate Window, choose Debug >Windows >Immediate or press Ctrl-Alt-I

enter image description here

Here is an example with Immediate Window:

int Sum(int x, int y) { return (x + y);}
void main(){
int a, b, c;
a = 5;
b = 7;
c = Sum(a, b);
char temp = getchar();}

add breakpoint

enter image description here

call commands

enter image description here

https://msdn.microsoft.com/en-us/library/f177hahy.aspx

INSERT VALUES WHERE NOT EXISTS

More of a comment link for suggested further reading...A really good blog article which benchmarks various ways of accomplishing this task can be found here.

They use a few techniques: "Insert Where Not Exists", "Merge" statement, "Insert Except", and your typical "left join" to see which way is the fastest to accomplish this task.

The example code used for each technique is as follows (straight copy/paste from their page) :

INSERT INTO #table1 (Id, guidd, TimeAdded, ExtraData)
SELECT Id, guidd, TimeAdded, ExtraData
FROM #table2
WHERE NOT EXISTS (Select Id, guidd From #table1 WHERE #table1.id = #table2.id)
-----------------------------------
MERGE #table1 as [Target]
USING  (select Id, guidd, TimeAdded, ExtraData from #table2) as [Source]
(id, guidd, TimeAdded, ExtraData)
    on [Target].id =[Source].id
WHEN NOT MATCHED THEN
    INSERT (id, guidd, TimeAdded, ExtraData)
    VALUES ([Source].id, [Source].guidd, [Source].TimeAdded, [Source].ExtraData);
------------------------------
INSERT INTO #table1 (id, guidd, TimeAdded, ExtraData)
SELECT id, guidd, TimeAdded, ExtraData from #table2
EXCEPT
SELECT id, guidd, TimeAdded, ExtraData from #table1
------------------------------
INSERT INTO #table1 (id, guidd, TimeAdded, ExtraData)
SELECT #table2.id, #table2.guidd, #table2.TimeAdded, #table2.ExtraData
FROM #table2
LEFT JOIN #table1 on #table1.id = #table2.id
WHERE #table1.id is null

It's a good read for those who are looking for speed! On SQL 2014, the Insert-Except method turned out to be the fastest for 50 million or more records.

How to search a string in multiple files and return the names of files in Powershell?

With PowerShell, go to the path where your files are and then type this command and replace ENTER THE STRING YOU SEARCH HERE (but keep the double quotes):

findstr /S /I /M /C:"ENTER THE STRING YOU SEARCH HERE" *.*

Have a nice day

The developers of this app have not set up this app properly for Facebook Login?

There are a bunch of possible things which could trigger this error:

In your case, you just need to add your facebook account into either tester, developer or admin of your facebook app as you want to use that account to test.

But if you see the error upon clicking connect to facebook(before you have chance to enter facebook credentials), then it means your current facebook account detected from cookie is not a valid tester/developer/admin account for your app. Your could either add your account in or just hit facebook.com and sign out(to remove the undesired cookie).

How to clear a textbox once a button is clicked in WPF?

For me texBoxName.Clear();is the best method because I have textboxs in binding and if I use other methods I do not have a good day

How to create directory automatically on SD card

Here is what works for me.

 uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" 

in your manifest and the code below

public static boolean createDirIfNotExists(String path) {
    boolean ret = true;

    File file = new File(Environment.getExternalStorageDirectory(), path);
    if (!file.exists()) {
        if (!file.mkdirs()) {
            Log.e("TravellerLog :: ", "Problem creating Image folder");
            ret = false;
        }
    }
    return ret;
}

How can I set size of a button?

Try with setPreferredSize instead of setSize.

UPDATE: GridLayout take up all space in its container, and BoxLayout seams to take up all the width in its container, so I added some glue-panels that are invisible and just take up space when the user stretches the window. I have just done this horizontally, and not vertically, but you could implement that in the same way if you want it.

Since GridLayout make all cells in the same size, it doesn't matter if they have a specified size. You have to specify a size for its container instead, as I have done.

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

public class PanelModel {
    public static void main(String[] args) {
        JFrame frame = new JFrame("Colored Trails");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JPanel mainPanel = new JPanel();
        mainPanel.setLayout(new BoxLayout(mainPanel, BoxLayout.Y_AXIS));

        JPanel firstPanel = new JPanel(new GridLayout(4, 4));
        firstPanel.setPreferredSize(new Dimension(4*100, 4*100));
        for (int i=1; i<=4; i++) {
            for (int j=1; j<=4; j++) {
                firstPanel.add(new JButton());
            }
        }

        JPanel firstGluePanel = new JPanel(new BorderLayout());
        firstGluePanel.add(firstPanel, BorderLayout.WEST);
        firstGluePanel.add(Box.createHorizontalGlue(), BorderLayout.CENTER);
        firstGluePanel.add(Box.createVerticalGlue(), BorderLayout.SOUTH);

        JPanel secondPanel = new JPanel(new GridLayout(13, 5));
        secondPanel.setPreferredSize(new Dimension(5*40, 13*40));
        for (int i=1; i<=5; i++) {
            for (int j=1; j<=13; j++) {
                secondPanel.add(new JButton());
            }
        }

        JPanel secondGluePanel = new JPanel(new BorderLayout());
        secondGluePanel.add(secondPanel, BorderLayout.WEST);
        secondGluePanel.add(Box.createHorizontalGlue(), BorderLayout.CENTER);
        secondGluePanel.add(Box.createVerticalGlue(), BorderLayout.SOUTH);

        mainPanel.add(firstGluePanel);
        mainPanel.add(secondGluePanel);
        frame.getContentPane().add(mainPanel);

        //frame.setSize(400,600);
        frame.pack();
        frame.setVisible(true);
    }
}

Getting only response header from HTTP POST using curl

The other answers require the response body to be downloaded. But there's a way to make a POST request that will only fetch the header:

curl -s -I -X POST http://www.google.com

An -I by itself performs a HEAD request which can be overridden by -X POST to perform a POST (or any other) request and still only get the header data.

Clicking submit button of an HTML form by a Javascript code

The usual way to submit a form in general is to call submit() on the form itself, as described in krtek's answer.

However, if you need to actually click a submit button for some reason (your code depends on the submit button's name/value being posted or something), you can click on the submit button itself like this:

document.getElementById('loginSubmit').click();

Best way to check for nullable bool in a condition expression (if ...)

If you're in a situation where you don't have control over whether part of the condition is checking a nullable value, you can always try the following:

if( someInt == 6 && someNullableBool == null ? false : (bool)someNullableBool){
    //perform your actions if true
}

I know it's not exactly a purist approach putting a ternary in an if statement but it does resolve the issue cleanly.

This is, of course, a manual way of saying GetValueOrDefault(false)

paint() and repaint() in Java

It's not necessary to call repaint unless you need to render something specific onto a component. "Something specific" meaning anything that isn't provided internally by the windowing toolkit you're using.

How to add empty spaces into MD markdown readme on GitHub?

Markdown really changes everything to html and html collapses spaces so you really can't do anything about it. You have to use the &nbsp; for it. A funny example here that I'm writing in markdown and I'll use couple of         here.

Above there are some &nbsp; without backticks

What is the intended use-case for git stash?

I will break answer on three paragraphs.

Part 1:

git stash (To save your un-committed changes in a "stash". Note: this removes changes from working tree!)

git checkout some_branch (change to intended branch -- in this case some_branch)

git stash list (list stashes)

You can see:
stash@{0}: WIP on {branch_name}: {SHA-1 of last commit} {last commit of you branch}
stash@{0}: WIP on master: 085b095c6 modification for test

git stash apply (to apply stash to working tree in current branch)

git stash apply stash@{12} (if you will have many stashes you can choose what stash will apply -- in this case we apply stash 12)

git stash drop stash@{0} (to remove from stash list -- in this case stash 0)

git stash pop stash@{1} (to apply selected stash and drop it from stash list)

Part 2:
You can hide your changes with this command but it is not necessary.
You can continue on the next day without stash.
This commands for hide your changes and work on different branches or for implementation some realisation of your code and save in stashes without branches and commitsor your custom case!
And later you can use some of stashes and check wich is better.

Part 3:
Stash command for local hide your changes.
If you want work remotely you must commit and push.

Update query PHP MySQL

you must write single quotes then double quotes then dot before name of field and after like that

mysql_query("UPDATE blogEntry SET content ='".$udcontent."', title = '".$udtitle."' WHERE id = '".$id."' ");

How do you subtract Dates in Java?

It's indeed one of the biggest epic failures in the standard Java API. Have a bit of patience, then you'll get your solution in flavor of the new Date and Time API specified by JSR 310 / ThreeTen which is (most likely) going to be included in the upcoming Java 8.

Until then, you can get away with JodaTime.

DateTime dt1 = new DateTime(2000, 1, 1, 0, 0, 0, 0);
DateTime dt2 = new DateTime(2010, 1, 1, 0, 0, 0, 0);
int days = Days.daysBetween(dt1, dt2).getDays();

Its creator, Stephen Colebourne, is by the way the guy behind JSR 310, so it'll look much similar.

How to change the font and font size of an HTML input tag?

<input type ="text" id="txtComputer">

css

input[type="text"]
{
    font-size:24px;
}

keytool error Keystore was tampered with, or password was incorrect

For me I solved it by changing passwords from Arabic letter to English letter, but first I went to the folder and deleted the generated key then it works.

long long int vs. long int vs. int64_t in C++

You don't need to go to 64-bit to see something like this. Consider int32_t on common 32-bit platforms. It might be typedef'ed as int or as a long, but obviously only one of the two at a time. int and long are of course distinct types.

It's not hard to see that there is no workaround which makes int == int32_t == long on 32-bit systems. For the same reason, there's no way to make long == int64_t == long long on 64-bit systems.

If you could, the possible consequences would be rather painful for code that overloaded foo(int), foo(long) and foo(long long) - suddenly they'd have two definitions for the same overload?!

The correct solution is that your template code usually should not be relying on a precise type, but on the properties of that type. The whole same_type logic could still be OK for specific cases:

long foo(long x);
std::tr1::disable_if(same_type(int64_t, long), int64_t)::type foo(int64_t);

I.e., the overload foo(int64_t) is not defined when it's exactly the same as foo(long).

[edit] With C++11, we now have a standard way to write this:

long foo(long x);
std::enable_if<!std::is_same<int64_t, long>::value, int64_t>::type foo(int64_t);

[edit] Or C++20

long foo(long x);
int64_t foo(int64_t) requires (!std::is_same_v<int64_t, long>);

How to start mongodb shell?

Try this:

mongod --fork --logpath /var/log/mongodb.log

You may need to create the db-folder:

mkdir -p /data/db

If you get any 'Permission denied'-error, I'ld recommend changing the permissions of the particular files instead of running mongod as root.

Convert a string to int using sql query

Also be aware that when converting from numeric string ie '56.72' to INT you may come up against a SQL error.

Conversion failed when converting the varchar value '56.72' to data type int.

To get around this just do two converts as follows:

STRING -> NUMERIC -> INT

or

SELECT CAST(CAST (MyVarcharCol AS NUMERIC(19,4)) AS INT)

When copying data from TableA to TableB, the conversion is implicit, so you dont need the second convert (if you are happy rounding down to nearest INT):

INSERT INTO TableB (MyIntCol)
SELECT CAST(MyVarcharCol AS NUMERIC(19,4)) as [MyIntCol]
FROM TableA

What is @ModelAttribute in Spring MVC?

For my style, I always use @ModelAttribute to catch object from spring form jsp. for example, I design form on jsp page, that form exist with commandName

<form:form commandName="Book" action="" methon="post">
      <form:input type="text" path="title"></form:input>
</form:form>

and I catch the object on controller with follow code

public String controllerPost(@ModelAttribute("Book") Book book)

and every field name of book must be match with path in sub-element of form

What are enums and why are they useful?

So far, I have never needed to use enums. I have been reading about them since they were introduced in 1.5 or version tiger as it was called back in the day. They never really solved a 'problem' for me. For those who use it (and I see a lot of them do), am sure it definitely serves some purpose. Just my 2 quid.

What is a regular expression for a MAC Address?

See this question also.

Regexes as follows:

^[0-9A-F]{2}:[0-9A-F]{2}:[0-9A-F]{2}:[0-9A-F]{2}:[0-9A-F]{2}:[0-9A-F]{2}$

^[0-9A-F]{2}-[0-9A-F]{2}-[0-9A-F]{2}-[0-9A-F]{2}-[0-9A-F]{2}-[0-9A-F]{2}$

How to invoke the super constructor in Python?

In line with the other answers, there are multiple ways to call super class methods (including the constructor), however in Python-3.x the process has been simplified:

Python-2.x

class A(object):
 def __init__(self):
   print "world"

class B(A):
 def __init__(self):
   print "hello"
   super(B, self).__init__()

Python-3.x

class A(object):
 def __init__(self):
   print("world")

class B(A):
 def __init__(self):
   print("hello")
   super().__init__()

super() is now equivalent to super(<containing classname>, self) as per the docs.

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

React Version

Make sure to have a header with 'content-type': 'multipart/form-data'

_handleSubmit(e) {
    e.preventDefault();
    const formData = new FormData();
          formData.append('file', this.state.file);
    const config = {
      headers: {
        'content-type': 'multipart/form-data'
      }
    }

     axios.post("/upload", formData, config)
         .then((resp) => {
             console.log(resp)
         }).catch((error) => {
    })
  }

  _handleImageChange(e) {
    e.preventDefault();
    let file = e.target.files[0];
    this.setState({
      file: file
    });
  }

View

  #html
 <input className="form-control"
    type="file" 
    onChange={(e)=>this._handleImageChange(e)} 
 />

How to make a machine trust a self-signed Java application

Just Go To *Startmenu >>Java >>Configure Java >> Security >> Edit site list >> copy and paste your Link with problem >> OK Problem fixed :)*

Trying to Validate URL Using JavaScript

In a similar situation I got away with this:

someUtils.validateURL = function(url) {
    var parser = document.createElement('a');
    try {
        parser.href = url;
        return !!parser.hostname;
    } catch (e) {
        return false;
    }
};

i.e. why invent the wheel if browsers can do it for you? But, of course, this will only work in the browser.

there are various parts of parsed URL exactly how browser would interpret it:

parser.protocol; // => "http:"
parser.hostname; // => "example.com"
parser.port;     // => "8080"
parser.pathname; // => "/path/"
parser.search;   // => "?search=test"
parser.hash;     // => "#hash"
parser.host;     // => "example.com:3000"

Using these you can improve your validating function depending on the requirements. The only drawback is that it will accept relative URLs and use current page server's host and port. But you can use it for your advantage, by re-assembling the URL from parts and always passing it in full to your AJAX service.

What validateURL won't accept is invalid URL, e.g. http:\:8883 will return false, but :1234 is valid and is interpreted as http://pagehost.example.com/:1234 i.e. as a relative path.

UPDATE

This approach is no longer working with Chrome and other WebKit browsers. Even when URL is invalid, hostname is filled with some value, e.g. taken from base. It still helps to parse parts of URL, but will not allow to validate one.

Possible better no-own-parser approach is to use var parsedURL = new URL(url) and catch exceptions. See e.g. URL API. Supported by all major browsers and NodeJS, although still marked experimental.

Get the first N elements of an array?

Use array_slice()

This is an example from the PHP manual: array_slice

$input = array("a", "b", "c", "d", "e");
$output = array_slice($input, 0, 3);   // returns "a", "b", and "c"

There is only a small issue

If the array indices are meaningful to you, remember that array_slice will reset and reorder the numeric array indices. You need the preserve_keys flag set to trueto avoid this. (4th parameter, available since 5.0.2).

Example:

$output = array_slice($input, 2, 3, true);

Output:

array([3]=>'c', [4]=>'d', [5]=>'e');

The declared package does not match the expected package ""

Make sure that Devices is defined as a source folder in the project properties.

How to catch segmentation fault in Linux?

Here's an example of how to do it in C.

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

void segfault_sigaction(int signal, siginfo_t *si, void *arg)
{
    printf("Caught segfault at address %p\n", si->si_addr);
    exit(0);
}

int main(void)
{
    int *foo = NULL;
    struct sigaction sa;

    memset(&sa, 0, sizeof(struct sigaction));
    sigemptyset(&sa.sa_mask);
    sa.sa_sigaction = segfault_sigaction;
    sa.sa_flags   = SA_SIGINFO;

    sigaction(SIGSEGV, &sa, NULL);

    /* Cause a seg fault */
    *foo = 1;

    return 0;
}

How to git reset --hard a subdirectory?

Try changing

git checkout -- a

to

git checkout -- `git ls-files -m -- a`

Since version 1.7.0, Git's ls-files honors the skip-worktree flag.

Running your test script (with some minor tweaks changing git commit... to git commit -q and git status to git status --short) outputs:

Initialized empty Git repository in /home/user/repo/.git/
After read-tree:
a/a/aa
a/b/ab
b/a/ba
After modifying:
b/a/ba
 D a/a/aa
 D a/b/ab
 M b/a/ba
After checkout:
 M b/a/ba
a/a/aa
a/c/ac
a/b/ab
b/a/ba

Running your test script with the proposed checkout change outputs:

Initialized empty Git repository in /home/user/repo/.git/
After read-tree:
a/a/aa
a/b/ab
b/a/ba
After modifying:
b/a/ba
 D a/a/aa
 D a/b/ab
 M b/a/ba
After checkout:
 M b/a/ba
a/a/aa
a/b/ab
b/a/ba

Calculating distance between two geographic locations

There is only one user Location, so you can iterate List of nearby places can call the distanceTo() function to get the distance, you can store in an array if you like.

From what I understand, distanceBetween() is for far away places, it's output is a WGS84 ellipsoid.

YouTube iframe API: how do I control an iframe player that's already in the HTML?

You can do this with far less code:

function callPlayer(func, args) {
    var i = 0,
        iframes = document.getElementsByTagName('iframe'),
        src = '';
    for (i = 0; i < iframes.length; i += 1) {
        src = iframes[i].getAttribute('src');
        if (src && src.indexOf('youtube.com/embed') !== -1) {
            iframes[i].contentWindow.postMessage(JSON.stringify({
                'event': 'command',
                'func': func,
                'args': args || []
            }), '*');
        }
    }
}

Working example: http://jsfiddle.net/kmturley/g6P5H/296/

HttpClient - A task was cancelled?

Promoting @JobaDiniz's comment to an answer:

Do not do the obvious thing and dispose the HttpClient instance, even though the code "looks right":

async Task<HttpResponseMessage> Method() {
  using (var client = new HttpClient())
    return client.GetAsync(request);
}

The same happens with C#'s new RIAA syntax; slightly less obvious:

async Task<HttpResponseMessage> Method() {
  using var client = new HttpClient();
  return client.GetAsync(request);
}

Instead, cache a static instance of HttpClient for your app or library, and reuse it:

static HttpClient client = new HttpClient();

async Task<HttpResponseMessage> Method() {
  return client.GetAsync(request);
}

(The Async() request methods are all thread safe.)

How to find the size of an int[]?

The "standard" C way to do this is

sizeof(list) / sizeof(list[0])

Confused about __str__ on list in Python

__str__ is only called when a string representation is required of an object.

For example str(uno), print "%s" % uno or print uno

However, there is another magic method called __repr__ this is the representation of an object. When you don't explicitly convert the object to a string, then the representation is used.

If you do this uno.neighbors.append([[str(due),4],[str(tri),5]]) it will do what you expect.

Cross browser method to fit a child div to its parent's width

The solution is to simply not declare width: 100%.

The default is width: auto, which for block-level elements (such as div), will take the "full space" available anyway (different to how width: 100% does it).

See: http://jsfiddle.net/U7PhY/2/

Just in case it's not already clear from my answer: just don't set a width on the child div.

You might instead be interested in box-sizing: border-box.

How to get the filename without the extension from a path in Python?

@IceAdor's refers to rsplit in a comment to @user2902201's solution. rsplit is the simplest solution that supports multiple periods.

Here it is spelt out:

file = 'my.report.txt'
print file.rsplit('.', 1)[0]

my.report

Multidimensional arrays in Swift

You are creating an array of three elements and assigning all three to the same thing, which is itself an array of three elements (three Doubles).

When you do the modifications you are modifying the floats in the internal array.

JQuery Event for user pressing enter in a textbox?

Here is a plugin for you: (Fiddle: http://jsfiddle.net/maniator/CjrJ7/)

$.fn.pressEnter = function(fn) {  

    return this.each(function() {  
        $(this).bind('enterPress', fn);
        $(this).keyup(function(e){
            if(e.keyCode == 13)
            {
              $(this).trigger("enterPress");
            }
        })
    });  
 }; 

//use it:
$('textarea').pressEnter(function(){alert('here')})

What does asterisk * mean in Python?

I find * useful when writing a function that takes another callback function as a parameter:

def some_function(parm1, parm2, callback, *callback_args):
    a = 1
    b = 2
    ...
    callback(a, b, *callback_args)
    ...

That way, callers can pass in arbitrary extra parameters that will be passed through to their callback function. The nice thing is that the callback function can use normal function parameters. That is, it doesn't need to use the * syntax at all. Here's an example:

def my_callback_function(a, b, x, y, z):
    ...

x = 5
y = 6
z = 7

some_function('parm1', 'parm2', my_callback_function, x, y, z)

Of course, closures provide another way of doing the same thing without requiring you to pass x, y, and z through some_function() and into my_callback_function().

How can I install a .ipa file to my iPhone simulator

First of all, IPAs usually only have ARM slices because the App Store does not currently accept Simulator slices in uploads.

Secondly, as of Xcode 8.3 you can drag & drop a .app bundle into the Simulator window and it will be installed. You can find the app in your build products directory ~/Library/Developer/Xcode/DerivedData/projectname-xyzzyabcdefg/Build/Products/Debug-iphonesimulator if you want to save it or distribute it to other people.

To install from the command line use xcrun simctl install <device> <path>.

device can be the device UUID, its name, or booted which means the currently booted device.

forward declaration of a struct in C?

Try this

#include <stdio.h>

struct context;

struct funcptrs{
  void (*func0)(struct context *ctx);
  void (*func1)(void);
};

struct context{
    struct funcptrs fps;
}; 

void func1 (void) { printf( "1\n" ); }
void func0 (struct context *ctx) { printf( "0\n" ); }

void getContext(struct context *con){
    con->fps.func0 = func0;  
    con->fps.func1 = func1;  
}

int main(int argc, char *argv[]){
 struct context c;
   c.fps.func0 = func0;
   c.fps.func1 = func1;
   getContext(&c);
   c.fps.func0(&c);
   getchar();
   return 0;
}

Bash script to cd to directory with spaces in pathname

A single backslash works for me:

ry4an@ry4an-mini:~$ mkdir "My Code"

ry4an@ry4an-mini:~$ vi todir.sh

ry4an@ry4an-mini:~$ . todir.sh 

ry4an@ry4an-mini:My Code$ cat ../todir.sh 
#!/bin/sh
cd ~/My\ Code

Are you sure the problem isn't that your shell script is changing directory in its subshell, but then you're back in the main shell (and original dir) when done? I avoided that by using . to run the script in the current shell, though most folks would just use an alias for this. The spaces could be a red herring.

Getting Keyboard Input

You can use Scanner class

To Read from Keyboard (Standard Input) You can use Scanner is a class in java.util package.

Scanner package used for obtaining the input of the primitive types like int, double etc. and strings. It is the easiest way to read input in a Java program, though not very efficient.

  1. To create an object of Scanner class, we usually pass the predefined object System.in, which represents the standard input stream (Keyboard).

For example, this code allows a user to read a number from System.in:

Scanner sc = new Scanner(System.in);
     int i = sc.nextInt();

Some Public methods in Scanner class.

  • hasNext() Returns true if this scanner has another token in its input.
  • nextInt() Scans the next token of the input as an int.
  • nextFloat() Scans the next token of the input as a float.
  • nextLine() Advances this scanner past the current line and returns the input that was skipped.
  • nextDouble() Scans the next token of the input as a double.
  • close() Closes this scanner.

For more details of Public methods in Scanner class.

Example:-

import java.util.Scanner;                      //importing class

class ScannerTest {
  public static void main(String args[]) {
    Scanner sc = new Scanner(System.in);       // Scanner object

    System.out.println("Enter your rollno");
    int rollno = sc.nextInt();
    System.out.println("Enter your name");
    String name = sc.next();
    System.out.println("Enter your fee");
    double fee = sc.nextDouble();
    System.out.println("Rollno:" + rollno + " name:" + name + " fee:" + fee);
    sc.close();                              // closing object
  }
}

Build a basic Python iterator

All answers on this page are really great for a complex object. But for those containing builtin iterable types as attributes, like str, list, set or dict, or any implementation of collections.Iterable, you can omit certain things in your class.

class Test(object):
    def __init__(self, string):
        self.string = string

    def __iter__(self):
        # since your string is already iterable
        return (ch for ch in self.string)
        # or simply
        return self.string.__iter__()
        # also
        return iter(self.string)

It can be used like:

for x in Test("abcde"):
    print(x)

# prints
# a
# b
# c
# d
# e

Git - How to fix "corrupted" interactive rebase?

I'm using git version 2.19.2.windows.1.

the only thing that worked for me was to remove the .git/rebase-apply/ directory and do a git reset --hard.

How to get current CPU and RAM usage in Python?

Taken feedback from first response and done small changes

            #!/usr/bin/env python
            #Execute commond on windows machine to install psutil>>>>python -m pip install psutil
            import psutil

            print ('                                                                   ')
            print ('----------------------CPU Information summary----------------------')
            print ('                                                                   ')

            # gives a single float value
            vcc=psutil.cpu_count()
            print ('Total number of CPUs :',vcc)

            vcpu=psutil.cpu_percent()
            print ('Total CPUs utilized percentage :',vcpu,'%')

            print ('                                                                   ')
            print ('----------------------RAM Information summary----------------------')
            print ('                                                                   ')
            # you can convert that object to a dictionary 
            #print(dict(psutil.virtual_memory()._asdict()))
            # gives an object with many fields
            vvm=psutil.virtual_memory()

            x=dict(psutil.virtual_memory()._asdict())

            def forloop():
                for i in x:
                    print (i,"--",x[i]/1024/1024/1024)#Output will be printed in GBs

            forloop()
            print ('                                                                   ')
            print ('----------------------RAM Utilization summary----------------------')
            print ('                                                                   ')
            # you can have the percentage of used RAM
            print('Percentage of used RAM :',psutil.virtual_memory().percent,'%')
            #79.2
            # you can calculate percentage of available memory
            print('Percentage of available RAM :',psutil.virtual_memory().available * 100 / psutil.virtual_memory().total,'%')
            #20.8

postgresql return 0 if returned value is null

(this answer was added to provide shorter and more generic examples to the question - without including all the case-specific details in the original question).


There are two distinct "problems" here, the first is if a table or subquery has no rows, the second is if there are NULL values in the query.

For all versions I've tested, postgres and mysql will ignore all NULL values when averaging, and it will return NULL if there is nothing to average over. This generally makes sense, as NULL is to be considered "unknown". If you want to override this you can use coalesce (as suggested by Luc M).

$ create table foo (bar int);
CREATE TABLE

$ select avg(bar) from foo;
 avg 
-----

(1 row)

$ select coalesce(avg(bar), 0) from foo;
 coalesce 
----------
        0
(1 row)

$ insert into foo values (3);
INSERT 0 1
$ insert into foo values (9);
INSERT 0 1
$ insert into foo values (NULL);
INSERT 0 1
$ select coalesce(avg(bar), 0) from foo;
      coalesce      
--------------------
 6.0000000000000000
(1 row)

of course, "from foo" can be replaced by "from (... any complicated logic here ...) as foo"

Now, should the NULL row in the table be counted as 0? Then coalesce has to be used inside the avg call.

$ select coalesce(avg(coalesce(bar, 0)), 0) from foo;
      coalesce      
--------------------
 4.0000000000000000
(1 row)

Colouring plot by factor in R

The command palette tells you the colours and their order when col = somefactor. It can also be used to set the colours as well.

palette()
[1] "black"   "red"     "green3"  "blue"    "cyan"    "magenta" "yellow"  "gray"   

In order to see that in your graph you could use a legend.

legend('topright', legend = levels(iris$Species), col = 1:3, cex = 0.8, pch = 1)

You'll notice that I only specified the new colours with 3 numbers. This will work like using a factor. I could have used the factor originally used to colour the points as well. This would make everything logically flow together... but I just wanted to show you can use a variety of things.

You could also be specific about the colours. Try ?rainbow for starters and go from there. You can specify your own or have R do it for you. As long as you use the same method for each you're OK.

cast or convert a float to nvarchar?

You can also do something:

SELECT CAST(CAST(34512367.392 AS decimal(30,9)) AS NVARCHAR(100))

Output: 34512367.392000000

Convert object to JSON in Android

Might be better choice:

@Override
public String toString() {
    return new GsonBuilder().create().toJson(this, Producto.class);
}

What is the best way to iterate over a dictionary?

I wrote an extension to loop over a dictionary.

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

Then you can call

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

String split on new line, tab and some number of spaces

Regex's aren't really the best tool for the job here. As others have said, using a combination of str.strip() and str.split() is the way to go. Here's a one liner to do it:

>>> data = '''\n\tName: John Smith
... \n\t  Home: Anytown USA
... \n\t    Phone: 555-555-555
... \n\t  Other Home: Somewhere Else
... \n\t Notes: Other data
... \n\tName: Jane Smith
... \n\t  Misc: Data with spaces'''
>>> {line.strip().split(': ')[0]:line.split(': ')[1] for line in data.splitlines() if line.strip() != ''}
{'Name': 'Jane Smith', 'Other Home': 'Somewhere Else', 'Notes': 'Other data', 'Misc': 'Data with spaces', 'Phone': '555-555-555', 'Home': 'Anytown USA'}

Check if DataRow exists by column name in c#?

if (drMyRow.Table.Columns["ColNameToCheck"] != null)
{
   doSomethingUseful;
{
else { return; }

Although the DataRow does not have a Columns property, it does have a Table that the column can be checked for.

Replace contents of factor column in R dataframe

I had the same problem. This worked better:

Identify which level you want to modify: levels(iris$Species)

    "setosa" "versicolor" "virginica" 

So, setosa is the first.

Then, write this:

     levels(iris$Species)[1] <-"new name"

WCF error - There was no endpoint listening at

I had the same issue. For me I noticed that the https is using another Certificate which was invalid in terms of expiration date. Not sure why it happened. I changed the Https port number and a new self signed cert. WCFtestClinet could connect to the server via HTTPS!

DBMS_OUTPUT.PUT_LINE not printing

For SQL Developer

You have to execute it manually

SET SERVEROUTPUT ON 

After that if you execute any procedure with DBMS_OUTPUT.PUT_LINE('info'); or directly .

This will print the line

And please don't try to add this

 SET SERVEROUTPUT ON

inside the definition of function and procedure, it will not compile and will not work.

ReactJS - Add custom event listener to component

If you need to handle DOM events not already provided by React you have to add DOM listeners after the component is mounted:

Update: Between React 13, 14, and 15 changes were made to the API that affect my answer. Below is the latest way using React 15 and ES7. See answer history for older versions.

class MovieItem extends React.Component {

  componentDidMount() {
    // When the component is mounted, add your DOM listener to the "nv" elem.
    // (The "nv" elem is assigned in the render function.)
    this.nv.addEventListener("nv-enter", this.handleNvEnter);
  }

  componentWillUnmount() {
    // Make sure to remove the DOM listener when the component is unmounted.
    this.nv.removeEventListener("nv-enter", this.handleNvEnter);
  }

  // Use a class arrow function (ES7) for the handler. In ES6 you could bind()
  // a handler in the constructor.
  handleNvEnter = (event) => {
    console.log("Nv Enter:", event);
  }

  render() {
    // Here we render a single <div> and toggle the "aria-nv-el-current" attribute
    // using the attribute spread operator. This way only a single <div>
    // is ever mounted and we don't have to worry about adding/removing
    // a DOM listener every time the current index changes. The attrs 
    // are "spread" onto the <div> in the render function: {...attrs}
    const attrs = this.props.index === 0 ? {"aria-nv-el-current": true} : {};

    // Finally, render the div using a "ref" callback which assigns the mounted 
    // elem to a class property "nv" used to add the DOM listener to.
    return (
      <div ref={elem => this.nv = elem} aria-nv-el {...attrs} className="menu_item nv-default">
        ...
      </div>
    );
  }

}

Example on Codepen.io

How to communicate between Docker containers via "hostname"

The new networking feature allows you to connect to containers by their name, so if you create a new network, any container connected to that network can reach other containers by their name. Example:

1) Create new network

$ docker network create <network-name>       

2) Connect containers to network

$ docker run --net=<network-name> ...

or

$ docker network connect <network-name> <container-name>

3) Ping container by name

docker exec -ti <container-name-A> ping <container-name-B> 

64 bytes from c1 (172.18.0.4): icmp_seq=1 ttl=64 time=0.137 ms
64 bytes from c1 (172.18.0.4): icmp_seq=2 ttl=64 time=0.073 ms
64 bytes from c1 (172.18.0.4): icmp_seq=3 ttl=64 time=0.074 ms
64 bytes from c1 (172.18.0.4): icmp_seq=4 ttl=64 time=0.074 ms

See this section of the documentation;

Note: Unlike legacy links the new networking will not create environment variables, nor share environment variables with other containers.

This feature currently doesn't support aliases

Unfinished Stubbing Detected in Mockito

org.mockito.exceptions.misusing.UnfinishedStubbingException: 
Unfinished stubbing detected here:
E.g. thenReturn() may be missing.

For mocking of void methods try out below:

//Kotlin Syntax

 Mockito.`when`(voidMethodCall())
           .then {
                Unit //Do Nothing
            }

SQL how to increase or decrease one for a int column in one command

If my understanding is correct, updates should be pretty simple. I would just do the following.

UPDATE TABLE SET QUANTITY = QUANTITY + 1 and
UPDATE TABLE SET QUANTITY = QUANTITY - 1 where QUANTITY > 0

You may need additional filters to just update a single row instead of all the rows.

For inserts, you can cache some unique id related to your record locally and check against this cache and decide whether to insert or not. The alternative approach is to always insert and check for PK violation error and ignore since this is a redundant insert.

Bulk Insert Correctly Quoted CSV File in SQL Server

I had the same problem, with data that only occasionally double-quotes some text. My solution is to let the BULK LOAD import the double-quotes, then run a REPLACE on the imported data.

For example:

bulk insert CodePoint_tbl from "F:\Data\Map\CodePointOpen\Data\CSV\ab.csv" with (FIRSTROW = 1, FIELDTERMINATOR = ',', ROWTERMINATOR='\n');

update CodePoint_tbl set Postcode = replace(Postcode,'"','') where charindex('"',Postcode) > 0

To make it less painful to write the REPLACE script, just copy and paste what you need from the results of something like this:

select C.ColID, C.[name] as Columnname into #Columns
from syscolumns C
join sysobjects T on C.id = T.id
where T.[name] = 'User_tbl'
order by 1;

declare @QUOTE char(1);
set @QUOTE = Char(39);
select 'Update User_tbl set '+ColumnName+'=replace('+ColumnName+','
 + @QUOTE + '"' + @QUOTE + ',' + @QUOTE + @QUOTE + ');
GO'
from #Columns
where ColID > 2
order by ColID;

Can I change the scroll speed using css or jQuery?

I just made a pure Javascript function based on that code. Javascript only version demo: http://jsbin.com/copidifiji

That is the independent code from jQuery

if (window.addEventListener) {window.addEventListener('DOMMouseScroll', wheel, false); 
window.onmousewheel = document.onmousewheel = wheel;}

function wheel(event) {
    var delta = 0;
    if (event.wheelDelta) delta = (event.wheelDelta)/120 ;
    else if (event.detail) delta = -(event.detail)/3;

    handle(delta);
    if (event.preventDefault) event.preventDefault();
    event.returnValue = false;
}

function handle(sentido) {
    var inicial = document.body.scrollTop;
    var time = 1000;
    var distance = 200;
  animate({
    delay: 0,
    duration: time,
    delta: function(p) {return p;},
    step: function(delta) {
window.scrollTo(0, inicial-distance*delta*sentido);   
    }});}

function animate(opts) {
  var start = new Date();
  var id = setInterval(function() {
    var timePassed = new Date() - start;
    var progress = (timePassed / opts.duration);
    if (progress > 1) {progress = 1;}
    var delta = opts.delta(progress);
    opts.step(delta);
    if (progress == 1) {clearInterval(id);}}, opts.delay || 10);
}

Where is svn.exe in my machine?

TortoiseSVN 1.7 has an option for installing the command line tools.

It isn't checked by default, but you can run the installer again and select it. It will also automatically update your PATH environment variable.

How to check whether a given string is valid JSON in Java

As you can see, there is a lot of solutions, they mainly parse the JSON to check it and at the end you will have to parse it to be sure.

But, depending on the context, you may improve the performances with a pre-check.

What I do when I call APIs, is just checking that the first character is '{' and the last is '}'. If it's not the case, I don't bother creating a parser.

jQuery - how can I find the element with a certain id?

As all html ids are unique in a valid html document why not search for the ID directly? If you're concerned if they type in an id that isn't a table then you can inspect the tag type that way?

Just an idea!

S

Best C++ IDE or Editor for Windows

There are the free "Express" versions of Visual Studio. Given that you like Visual Studio and that the "Express" editions are free, there is no reason to use any other editor.

How to indent/format a selection of code in Visual Studio Code with Ctrl + Shift + F

This should be able to set to whatever keybindings you want for indent/outdent here:

Menu FilePreferencesKeyboard Shortcuts

editor.action.indentLines

editor.action.outdentLines

How to fill Dataset with multiple tables?

If you are issuing a single command with several select statements, you might use NextResult method to move to next resultset within the datareader: http://msdn.microsoft.com/en-us/library/system.data.idatareader.nextresult.aspx

I show how it could look bellow:

public DataSet SelectOne(int id)
{
    DataSet result = new DataSet();
    using (DbCommand command = Connection.CreateCommand())
    {
        command.CommandText = @"
select * from table1
select * from table2
        ";

        var param = ParametersBuilder.CreateByKey(command, "ID", id, null);
        command.Parameters.Add(param);

        Connection.Open();
        using (DbDataReader reader = command.ExecuteReader())
        {
            result.MainTable.Load(reader);
            reader.NextResult();
            result.SecondTable.Load(reader);
            // ...
        }
        Connection.Close();
    }
    return result;
}

What are differences between AssemblyVersion, AssemblyFileVersion and AssemblyInformationalVersion?

AssemblyVersion pretty much stays internal to .NET, while AssemblyFileVersion is what Windows sees. If you go to the properties of an assembly sitting in a directory and switch to the version tab, the AssemblyFileVersion is what you'll see up top. If you sort files by version, this is what's used by Explorer.

The AssemblyInformationalVersion maps to the "Product Version" and is meant to be purely "human-used".

AssemblyVersion is certainly the most important, but I wouldn't skip AssemblyFileVersion, either. If you don't provide AssemblyInformationalVersion, the compiler adds it for you by stripping off the "revision" piece of your version number and leaving the major.minor.build.

Conversion from 12 hours time to 24 hours time in java

Assuming that you use SimpleDateFormat implicitly or explicitly, you need to use H instead of h in the format string.

E.g

HH:mm:ss

instead of

hh:mm:ss

Using Linq select list inside list

After my previous answer disaster, I'm going to try something else.

List<Model> usrList  = 
(list.Where(n => n.application == "applicationame").ToList());
usrList.ForEach(n => n.users.RemoveAll(n => n.surname != "surname"));

How to set up a cron job to run an executable every hour?

Since I could not run the C executable that way, I wrote a simple shell script that does the following

cd /..path_to_shell_script
./c_executable_name

In the cron jobs list, I call the shell script.

How to rename uploaded file before saving it into a directory?

You can simply change the name of the file by changing the name of the file in the second parameter of move_uploaded_file.

Instead of

move_uploaded_file($_FILES["file"]["tmp_name"], "../img/imageDirectory/" . $_FILES["file"]["name"]);

Use

$temp = explode(".", $_FILES["file"]["name"]);
$newfilename = round(microtime(true)) . '.' . end($temp);
move_uploaded_file($_FILES["file"]["tmp_name"], "../img/imageDirectory/" . $newfilename);

Changed to reflect your question, will product a random number based on the current time and append the extension from the originally uploaded file.

Where is the application.properties file in a Spring Boot project?

You will need to add the application.properties file in your classpath.

If you are using Maven or Gradle, you can just put the file under src/main/resources.
If you are not using Maven or any other build tools, put that under your src folder and you should be fine.

Then you can just add an entry server.port = xxxx in the properties file.

how to properly display an iFrame in mobile safari

The solution is to use Scrolling="no" on the iframe.

That's it.

Eclipse executable launcher error: Unable to locate companion shared library

I've just encountered the same issue. The problem for me was Windows 7 default unzipper program. It has a problem when it encounters files that have a deep file structure. I read about this issue some time ago but can't recall the article. Fix for me is to unzip the Eclipse download using WinZip (or some other tool which does'nt have this issue).

Targeting only Firefox with CSS

The only way to do this is via various CSS hacks, which will make your page much more likely to fail on the next browser updates. If anything, it will be LESS safe than using a js-browser sniffer.

How to set specific window (frame) size in java swing?

Most layout managers work best with a component's preferredSize, and most GUI's are best off allowing the components they contain to set their own preferredSizes based on their content or properties. To use these layout managers to their best advantage, do call pack() on your top level containers such as your JFrames before making them visible as this will tell these managers to do their actions -- to layout their components.

Often when I've needed to play a more direct role in setting the size of one of my components, I'll override getPreferredSize and have it return a Dimension that is larger than the super.preferredSize (or if not then it returns the super's value).

For example, here's a small drag-a-rectangle app that I created for another question on this site:

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

public class MoveRect extends JPanel {
   private static final int RECT_W = 90;
   private static final int RECT_H = 70;
   private static final int PREF_W = 600;
   private static final int PREF_H = 300;
   private static final Color DRAW_RECT_COLOR = Color.black;
   private static final Color DRAG_RECT_COLOR = new Color(180, 200, 255);
   private Rectangle rect = new Rectangle(25, 25, RECT_W, RECT_H);
   private boolean dragging = false;
   private int deltaX = 0;
   private int deltaY = 0;

   public MoveRect() {
      MyMouseAdapter myMouseAdapter = new MyMouseAdapter();
      addMouseListener(myMouseAdapter);
      addMouseMotionListener(myMouseAdapter);
   }

   @Override
   protected void paintComponent(Graphics g) {
      super.paintComponent(g);
      if (rect != null) {
         Color c = dragging ? DRAG_RECT_COLOR : DRAW_RECT_COLOR;
         g.setColor(c);
         Graphics2D g2 = (Graphics2D) g;
         g2.draw(rect);
      }
   }

   @Override
   public Dimension getPreferredSize() {
      return new Dimension(PREF_W, PREF_H);
   }

   private class MyMouseAdapter extends MouseAdapter {

      @Override
      public void mousePressed(MouseEvent e) {
         Point mousePoint = e.getPoint();
         if (rect.contains(mousePoint)) {
            dragging = true;
            deltaX = rect.x - mousePoint.x;
            deltaY = rect.y - mousePoint.y;
         }
      }

      @Override
      public void mouseReleased(MouseEvent e) {
         dragging = false;
         repaint();
      }

      @Override
      public void mouseDragged(MouseEvent e) {
         Point p2 = e.getPoint();
         if (dragging) {
            int x = p2.x + deltaX;
            int y = p2.y + deltaY;
            rect = new Rectangle(x, y, RECT_W, RECT_H);
            MoveRect.this.repaint();
         }
      }
   }

   private static void createAndShowGui() {
      MoveRect mainPanel = new MoveRect();

      JFrame frame = new JFrame("MoveRect");
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.getContentPane().add(mainPanel);
      frame.pack();
      frame.setLocationByPlatform(true);
      frame.setVisible(true);
   }

   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {
         public void run() {
            createAndShowGui();
         }
      });
   }
}

Note that my main class is a JPanel, and that I override JPanel's getPreferredSize:

public class MoveRect extends JPanel {
   //.... deleted constants

   private static final int PREF_W = 600;
   private static final int PREF_H = 300;

   //.... deleted fields and constants

   //... deleted methods and constructors

   @Override
   public Dimension getPreferredSize() {
      return new Dimension(PREF_W, PREF_H);
   }

Also note that when I display my GUI, I place it into a JFrame, call pack(); on the JFrame, set its position, and then call setVisible(true); on my JFrame:

   private static void createAndShowGui() {
      MoveRect mainPanel = new MoveRect();

      JFrame frame = new JFrame("MoveRect");
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.getContentPane().add(mainPanel);
      frame.pack();
      frame.setLocationByPlatform(true);
      frame.setVisible(true);
   }

   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {
         public void run() {
            createAndShowGui();
         }
      });
   }
}

How can I merge two commits into one if I already started rebase?

If your master branch git log looks something like following:

commit ac72a4308ba70cc42aace47509a5e
Author: <[email protected]>
Date:   Tue Jun 11 10:23:07 2013 +0500

    Added algorithms for Cosine-similarity

commit 77df2a40e53136c7a2d58fd847372
Author: <[email protected]>
Date:   Tue Jun 11 13:02:14 2013 -0700

    Set stage for similar objects

commit 249cf9392da197573a17c8426c282
Author: Ralph <[email protected]>
Date:   Thu Jun 13 16:44:12 2013 -0700

    Fixed a bug in space world automation

and you want to merge the top two commits just do following easy steps:

  1. First to be on safe side checkout the second last commit in a separate branch. You can name the branch anything. git checkout 77df2a40e53136c7a2d58fd847372 -b merged-commits
  2. Now, just cherry-pick your changes from the last commit into this new branch as: git cherry-pick -n -x ac72a4308ba70cc42aace47509a5e. (Resolve conflicts if arise any)
  3. So now, your changes in last commit are there in your second last commit. But you still have to commit, so first add the changes you just cherry-picked and then execute git commit --amend.

That's it. You may push this merged version in branch "merged-commits" if you like.

Also, you can discard the back-to-back two commits in your master branch now. Just update your master branch as:

git checkout master
git reset --hard origin/master (CAUTION: This command will remove any local changes to your master branch)
git pull

Graph implementation C++

There can be an even simpler representation assuming that one has to only test graph algorithms not use them(graph) else where. This can be as a map from vertices to their adjacency lists as shown below :-

#include<bits/stdc++.h>
using namespace std;

/* implement the graph as a map from the integer index as a key to the   adjacency list
 * of the graph implemented as a vector being the value of each individual key. The
 * program will be given a matrix of numbers, the first element of each row will
 * represent the head of the adjacency list and the rest of the elements will be the
 * list of that element in the graph.
*/

typedef map<int, vector<int> > graphType;

int main(){

graphType graph;
int vertices = 0;

cout << "Please enter the number of vertices in the graph :- " << endl;
cin >> vertices;
if(vertices <= 0){
    cout << "The number of vertices in the graph can't be less than or equal to 0." << endl;
    exit(0);
}

cout << "Please enter the elements of the graph, as an adjacency list, one row after another. " << endl;
for(int i = 0; i <= vertices; i++){

    vector<int> adjList;                    //the vector corresponding to the adjacency list of each vertex

    int key = -1, listValue = -1;
    string listString;
    getline(cin, listString);
    if(i != 0){
        istringstream iss(listString);
        iss >> key;
        iss >> listValue;
        if(listValue != -1){
            adjList.push_back(listValue);
            for(; iss >> listValue; ){
                adjList.push_back(listValue);
            }
            graph.insert(graphType::value_type(key, adjList));
        }
        else
            graph.insert(graphType::value_type(key, adjList));
    }
}

//print the elements of the graph
cout << "The graph that you entered :- " << endl;
for(graphType::const_iterator iterator = graph.begin(); iterator != graph.end(); ++iterator){
    cout << "Key : " << iterator->first << ", values : ";

    vector<int>::const_iterator vectBegIter = iterator->second.begin();
    vector<int>::const_iterator vectEndIter = iterator->second.end();
    for(; vectBegIter != vectEndIter; ++vectBegIter){
        cout << *(vectBegIter) << ", ";
    }
    cout << endl;
}
}

MySQL LEFT JOIN 3 tables

try this

    SELECT p.Name, p.SS, f.Fear 
    FROM Persons p 
    LEFT JOIN Person_Fear fp 
    ON p.PersonID = fp.PersonID
    LEFT JOIN Fear f
    ON f.FearID = fp.FearID

How can I send and receive WebSocket messages on the server side?

C++ Implementation (not by me) here. Note that when your bytes are over 65535, you need to shift with a long value as shown here.

Build the full path filename in Python

This works fine:

os.path.join(dir_name, base_filename + "." + filename_suffix)

Keep in mind that os.path.join() exists only because different operating systems use different path separator characters. It smooths over that difference so cross-platform code doesn't have to be cluttered with special cases for each OS. There is no need to do this for file name "extensions" (see footnote) because they are always connected to the rest of the name with a dot character, on every OS.

If using a function anyway makes you feel better (and you like needlessly complicating your code), you can do this:

os.path.join(dir_name, '.'.join((base_filename, filename_suffix)))

If you prefer to keep your code clean, simply include the dot in the suffix:

suffix = '.pdf'
os.path.join(dir_name, base_filename + suffix)

That approach also happens to be compatible with the suffix conventions in pathlib, which was introduced in python 3.4 after this question was asked. New code that doesn't require backward compatibility can do this:

suffix = '.pdf'
pathlib.PurePath(dir_name, base_filename + suffix)

You might prefer the shorter Path instead of PurePath if you're only handling paths for the local OS.

Warning: Do not use pathlib's with_suffix() for this purpose. That method will corrupt base_filename if it ever contains a dot.


Footnote: Outside of Micorsoft operating systems, there is no such thing as a file name "extension". Its presence on Windows comes from MS-DOS and FAT, which borrowed it from CP/M, which has been dead for decades. That dot-plus-three-letters that many of us are accustomed to seeing is just part of the file name on every other modern OS, where it has no built-in meaning.

How to properly set the 100% DIV height to match document/window height?

Use #element{ height:100vh}

This will set the height of the #element to 100% of viewport. Hope this helps.

Git and nasty "error: cannot lock existing info/refs fatal"

This sounds like a permissions issue - is it possible you had two windows open, executing with separate rights? Perhaps check ownership of the .git folder.

Perhaps check to see if there is an outstanding file lock open, maybe use lsof to check, or the equivalent for your OS.

Convert NVARCHAR to DATETIME in SQL Server 2008

DECLARE @chr nvarchar(50) = (SELECT CONVERT(nvarchar(50), GETDATE(), 103))

SELECT @chr chars, CONVERT(date, @chr, 103) date_again

Concatenate a vector of strings/character

Try using an empty collapse argument within the paste function:

paste(sdata, collapse = '')

Thanks to http://twitter.com/onelinetips/status/7491806343

How can I get the count of line in a file in an efficient way?

I found some solution for this, it might useful for you

Below is the code snippet for, count the no.of lines from the file.

  File file = new File("/mnt/sdcard/abc.txt");
  LineNumberReader lineNumberReader = new LineNumberReader(new FileReader(file));
  lineNumberReader.skip(Long.MAX_VALUE);
  int lines = lineNumberReader.getLineNumber();
  lineNumberReader.close();

What is aria-label and how should I use it?

It's an attribute designed to help assistive technology (e.g. screen readers) attach a label to an otherwise anonymous HTML element.

So there's the <label> element:

<label for="fmUserName">Your name</label>
<input id="fmUserName">

The <label> explicitly tells the user to type their name into the input box where id="fmUserName".

aria-label does much the same thing, but it's for those cases where it isn't practical or desirable to have a label on screen. Take the MDN example:

<button aria-label="Close" onclick="myDialog.close()">X</button>`

Most people would be able to infer visually that this button will close the dialog. A blind person using assistive technology might just hear "X" read aloud, which doesn't mean much without the visual clues. aria-label explicitly tells them what the button will do.

How do I capture the output into a variable from an external process in PowerShell?

I use the following:

Function GetProgramOutput([string]$exe, [string]$arguments)
{
    $process = New-Object -TypeName System.Diagnostics.Process
    $process.StartInfo.FileName = $exe
    $process.StartInfo.Arguments = $arguments
    
    $process.StartInfo.UseShellExecute = $false
    $process.StartInfo.RedirectStandardOutput = $true
    $process.StartInfo.RedirectStandardError = $true
    $process.Start()
    
    $output = $process.StandardOutput.ReadToEnd()   
    $err = $process.StandardError.ReadToEnd()
    
    $process.WaitForExit()
    
    $output
    $err
}
    
$exe = "C:\Program Files\7-Zip\7z.exe"
$arguments = "i"
    
$runResult = (GetProgramOutput $exe $arguments)
$stdout = $runResult[-2]
$stderr = $runResult[-1]
    
[System.Console]::WriteLine("Standard out: " + $stdout)
[System.Console]::WriteLine("Standard error: " + $stderr)

Why is division in Ruby returning an integer instead of decimal value?

Fixnum#to_r is not mentioned here, it was introduced since ruby 1.9. It converts Fixnum into rational form. Below are examples of its uses. This also can give exact division as long as all the numbers used are Fixnum.

 a = 1.to_r  #=> (1/1) 
 a = 10.to_r #=> (10/1) 
 a = a / 3   #=> (10/3) 
 a = a * 3   #=> (10/1) 
 a.to_f      #=> 10.0

Example where a float operated on a rational number coverts the result to float.

a = 5.to_r   #=> (5/1) 
a = a * 5.0  #=> 25.0 

Getting "method not valid without suitable object" error when trying to make a HTTP request in VBA?

For reading REST data, at least OData Consider Microsoft Power Query. You won't be able to write data. However, you can read data very well.

Wait for all promises to resolve

You can use "await" in an "async function".

app.controller('MainCtrl', async function($scope, $q, $timeout) {
  ...
  var all = await $q.all([one.promise, two.promise, three.promise]); 
  ...
}

NOTE: I'm not 100% sure you can call an async function from a non-async function and have the right results.

That said this wouldn't ever be used on a website. But for load-testing/integration test...maybe.

Example code:

_x000D_
_x000D_
async function waitForIt(printMe) {_x000D_
  console.log(printMe);_x000D_
  console.log("..."+await req());_x000D_
  console.log("Legendary!")_x000D_
}_x000D_
_x000D_
function req() {_x000D_
  _x000D_
  var promise = new Promise(resolve => {_x000D_
    setTimeout(() => {_x000D_
      resolve("DARY!");_x000D_
    }, 2000);_x000D_
    _x000D_
  });_x000D_
_x000D_
    return promise;_x000D_
}_x000D_
_x000D_
waitForIt("Legen-Wait For It");
_x000D_
_x000D_
_x000D_

Can you disable tabs in Bootstrap?

Most easy and clean solution to avoid this is adding onclick="return false;" to a tag.

<ul class="nav nav-tabs">
    <li class="active">
        <a href="#home" onclick="return false;">Home</a>
    </li>    
    <li>
        <a href="#ApprovalDetails" onclick="return false;">Approval Details</a>
    </li>
</ul>
  • Adding "cursor:no-drop;" just makes cursor look disabled, but is clickable, Url gets appending with href target for ex page.apsx#Home
  • No need of adding "disabled" class to <li> AND removing href

How to make rectangular image appear circular with CSS

<html>
    <head>
<script src="//code.jquery.com/jquery-1.11.0.min.js"></script>
    <style>
    .round_img {
    border-radius: 50%;
    max-width: 150px;
    border: 1px solid #ccc;
    }
    </style>
    <script>
    var cw = $('.round_img').width();
    $('.round_img').css({
    'height': cw + 'px'
    });
    </script>
    </head>
    <body>
    <img class="round_img" src="image.jpg" alt="" title="" />
    </body>
</html>

http://jsfiddle.net/suryakiran/1xqs4ztc/

Setting environment variables on OS X

For a single user modification, use ~/.profile of the ones you listed. The following link explains when the different files are read by Bash.

http://telin.ugent.be/~slippens/drupal/bashrc_and_others

If you want to set the environment variable for gui applications you need the ~/.MacOSX/environment.plist file