Programs & Examples On #Fubumvc

FubuMVC is an open source Front Controller-style MVC framework designed primarily for Web applications built on ASP.NET.

Can Google Chrome open local links?

This question is dated, but I had the same problem just now, the solution I found was to map a virtual directory in IIS to the networked drive with the documents, so the url became a friendly "http://" address.

Setting virtual directories:

IIS:

http://www.iis.net/configreference/system.applicationhost/sites/site/application/virtualdirectory

Apache:

http://w3shaman.com/article/creating-virtual-directory-apache

Cheers!

how to convert a string to an array in php

$array = explode(' ', $string);

Explaining the 'find -mtime' command

To find all files modified in the last 24 hours use the one below. The -1 here means changed 1 day or less ago.

find . -mtime -1 -ls

How to check version of a CocoaPods framework

Podfile.lock file right under Podfile within your project.

The main thing is , Force it to open through your favourite TextEditor, like Sublime or TextEdit [Open With -> Select Sublime] as it doesn't give an option straight away to open.

How to list the contents of a package using YUM?

I don't think you can list the contents of a package using yum, but if you have the .rpm file on your local system (as will most likely be the case for all installed packages), you can use the rpm command to list the contents of that package like so:

rpm -qlp /path/to/fileToList.rpm

If you don't have the package file (.rpm), but you have the package installed, try this:

rpm -ql packageName

Javascript Equivalent to PHP Explode()

So I know that this post is pretty old, but I figured I may as well add a function that has helped me over the years. Why not just remake the explode function using split as mentioned above? Well here it is:

function explode(str,begin,end)
{
   t=str.split(begin);
   t=t[1].split(end);
   return t[0];
}

This function works well if you are trying to get the values between two values. For instance:

data='[value]insertdataherethatyouwanttoget[/value]';

If you were interested in getting the information from between the two [values] "tags", you could use the function like the following.

out=explode(data,'[value]','[/value]');
//Variable out would display the string: insertdataherethatyouwanttoget

But let's say you don't have those handy "tags" like the example above displayed. No matter.

out=explode(data,'insert','wanttoget');
//Now out would display the string: dataherethatyou

Wana see it in action? Click here.

SQL Update with row_number()

If table does not have relation, just copy all in new table with row number and remove old and rename new one with old one.

Select   RowNum = ROW_NUMBER() OVER(ORDER BY(SELECT NULL)) , * INTO cdm.dbo.SALES2018 from 
(
select * from SALE2018) as SalesSource

Converting a factor to numeric without losing information R (as.numeric() doesn't seem to work)

First, factor consists of indices and levels. This fact is very very important when you are struggling with factor.

For example,

> z <- factor(letters[c(3, 2, 3, 4)])

# human-friendly display, but internal structure is invisible
> z
[1] c b c d
Levels: b c d

# internal structure of factor
> unclass(z)
[1] 2 1 2 3
attr(,"levels")
[1] "b" "c" "d"

here, z has 4 elements.
The index is 2, 1, 2, 3 in that order.
The level is associated with each index: 1 -> b, 2 -> c, 3 -> d.

Then, as.numeric converts simply the index part of factor into numeric.
as.character handles the index and levels, and generates character vector expressed by its level.

?as.numeric says that Factors are handled by the default method.

How to get relative path from absolute path

If you know that toPath is contained by fromPath then you can keep it simple. I'll leave out the asserts for brevity.

public static string MakeRelativePath(string fromPath, string toPath)
{
    // use Path.GetFullPath to canonicalise the paths (deal with multiple directory seperators, etc)
    return Path.GetFullPath(toPath).Substring(Path.GetFullPath(fromPath).Length + 1);
}

RegEx: Grabbing values between quotation marks

MORE ANSWERS! Here is the solution i used

\"([^\"]*?icon[^\"]*?)\"

TLDR;
replace the word icon with what your looking for in said quotes and voila!


The way this works is it looks for the keyword and doesn't care what else in between the quotes. EG:
id="fb-icon"
id="icon-close"
id="large-icon-close"
the regex looks for a quote mark "
then it looks for any possible group of letters thats not "
until it finds icon
and any possible group of letters that is not "
it then looks for a closing "

mysqldump exports only one table

In case you encounter an error like this

mysqldump: 1044 Access denied when using LOCK TABLES

A quick workaround is to pass the –-single-transaction option to mysqldump.

So your command will be like this.

mysqldump --single-transaction -u user -p DBNAME > backup.sql

getting the screen density programmatically in android?

This should work.

DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);
int width = dm.widthPixels; //320
int height = dm.heightPixels; //480

creating an array of structs in c++

Try this:

Customer customerRecords[2] = {{25, "Bob Jones"},
                               {26, "Jim Smith"}};

How can I send JSON response in symfony2 controller

Symfony 2.1 has a JsonResponse class.

return new JsonResponse(array('name' => $name));

The passed in array will be JSON encoded the status code will default to 200 and the content type will be set to application/json.

There is also a handy setCallback function for JSONP.

How to find out when an Oracle table was updated the last time

Since you are on 10g, you could potentially use the ORA_ROWSCN pseudocolumn. That gives you an upper bound of the last SCN (system change number) that caused a change in the row. Since this is an increasing sequence, you could store off the maximum ORA_ROWSCN that you've seen and then look only for data with an SCN greater than that.

By default, ORA_ROWSCN is actually maintained at the block level, so a change to any row in a block will change the ORA_ROWSCN for all rows in the block. This is probably quite sufficient if the intention is to minimize the number of rows you process multiple times with no changes if we're talking about "normal" data access patterns. You can rebuild the table with ROWDEPENDENCIES which will cause the ORA_ROWSCN to be tracked at the row level, which gives you more granular information but requires a one-time effort to rebuild the table.

Another option would be to configure something like Change Data Capture (CDC) and to make your OCI application a subscriber to changes to the table, but that also requires a one-time effort to configure CDC.

How to generate a QR Code for an Android application?

zxing does not (only) provide a web API; really, that is Google providing the API, from source code that was later open-sourced in the project.

As Rob says here you can use the Java source code for the QR code encoder to create a raw barcode and then render it as a Bitmap.

I can offer an easier way still. You can call Barcode Scanner by Intent to encode a barcode. You need just a few lines of code, and two classes from the project, under android-integration. The main one is IntentIntegrator. Just call shareText().

Viewing local storage contents on IE

In IE11, you can see local storage in console on dev tools:

  1. Show dev tools (press F12)
  2. Click "Console" or press Ctrl+2
  3. Type localStorage and press Enter

Also, if you need to clear the localStorage, type localStorage.clear() on console.

How to convert a selection to lowercase or uppercase in Sublime Text

For Windows:

  • Ctrl+K,Ctrl+U for UPPERCASE.
  • Ctrl+K,Ctrl+L for lowercase.

Method 1 (Two keys pressed at a time)

  1. Press Ctrl and hold.
  2. Now press K, release K while holding Ctrl. (Do not release the Ctrl key)
  3. Immediately, press U (for uppercase) OR L (for lowercase) with Ctrl still being pressed, then release all pressed keys.

Method 2 (3 keys pressed at a time)

  1. Press Ctrl and hold.
  2. Now press K.
  3. Without releasing Ctrl and K, immediately press U (for uppercase) OR L (for lowercase) and release all pressed keys.

Please note: If you press and hold Ctrl+K for more than two seconds it will start deleting text so try to be quick with it.

I use the above shortcuts, and they work on my Windows system.

Recursively looping through an object to build a property list

UPDATE: JUST USE JSON.stringify to print objects on screen!

All you need is this line:

document.body.innerHTML = '<pre>' + JSON.stringify(ObjectWithSubObjects, null, "\t") + '</pre>';

This is my older version of printing objects recursively on screen:

 var previousStack = '';
    var output = '';
    function objToString(obj, stack) {
        for (var property in obj) {
            var tab = '&nbsp;&nbsp;&nbsp;&nbsp;';
            if (obj.hasOwnProperty(property)) {
                if (typeof obj[property] === 'object' && typeof stack === 'undefined') {
                    config = objToString(obj[property], property);
                } else {
                    if (typeof stack !== 'undefined' && stack !== null && stack === previousStack) {
                        output = output.substring(0, output.length - 1);  // remove last }
                        output += tab + '<span>' + property + ': ' + obj[property] + '</span><br />'; // insert property
                        output += '}';   // add last } again
                    } else {
                        if (typeof stack !== 'undefined') {
                            output += stack + ': {  <br />' + tab;
                        }
                        output += '<span>' + property + ': ' + obj[property] + '</span><br />';
                        if (typeof stack !== 'undefined') {
                            output += '}';
                        }
                    }
                    previousStack = stack;
                }
            }
        }
        return output;
    }

Usage:

document.body.innerHTML = objToString(ObjectWithSubObjects);

Example output:

cache: false
position: fixed
effect: { 
    fade: false
    fall: true
}

Obviously this can be improved by adding comma's when needed and quotes from string values. But this was good enough for my case.

How to Multi-thread an Operation Within a Loop in Python

You can split the processing into a specified number of threads using an approach like this:

import threading                                                                

def process(items, start, end):                                                 
    for item in items[start:end]:                                               
        try:                                                                    
            api.my_operation(item)                                              
        except Exception:                                                       
            print('error with item')                                            


def split_processing(items, num_splits=4):                                      
    split_size = len(items) // num_splits                                       
    threads = []                                                                
    for i in range(num_splits):                                                 
        # determine the indices of the list this thread will handle             
        start = i * split_size                                                  
        # special case on the last chunk to account for uneven splits           
        end = None if i+1 == num_splits else (i+1) * split_size                 
        # create the thread                                                     
        threads.append(                                                         
            threading.Thread(target=process, args=(items, start, end)))         
        threads[-1].start() # start the thread we just created                  

    # wait for all threads to finish                                            
    for t in threads:                                                           
        t.join()                                                                



split_processing(items)

Slide right to left Android Animations

<translate
    android:fromXDelta="100%p"
    android:toXDelta="0%p"
    android:duration="500" />

What is Mocking?

Mock is a method/object that simulates the behavior of a real method/object in controlled ways. Mock objects are used in unit testing.

Often a method under a test calls other external services or methods within it. These are called dependencies. Once mocked, the dependencies behave the way we defined them.

With the dependencies being controlled by mocks, we can easily test the behavior of the method that we coded. This is Unit testing.

What is the purpose of mock objects?

Mocks vs stubs

Unit tests vs Functional tests

How can I read the contents of an URL with Python?

None of these answers are very good for Python 3 (tested on latest version at the time of this post).

This is how you do it...

import urllib.request

try:
   with urllib.request.urlopen('http://www.python.org/') as f:
      print(f.read().decode('utf-8'))
except urllib.error.URLError as e:
   print(e.reason)

The above is for contents that return 'utf-8'. Remove .decode('utf-8') if you want python to "guess the appropriate encoding."

Documentation: https://docs.python.org/3/library/urllib.request.html#module-urllib.request

Pycharm/Python OpenCV and CV2 install error

Installing opencv is not that direct. You need to pre-install some packages first.

I would not recommend the unofficial package opencv-python. Does not work properly in macos and ubuntu (see this post). No idea about windows.

There are many webs explaining how to install opencv and all required packages. For example this one.

The problem of trying to install opencv several times is that you need to uninstall completely before attempting again, or you might end having many errors.

Error message 'Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.'

I got this problem when I installed a NuGet package on one of the projects and forgot to update the other project.

I solved this by just making both projects having the same reference assembly.

mongodb count num of distinct values per field/key

With MongoDb 3.4.4 and newer, you can leverage the use of $arrayToObject operator and a $replaceRoot pipeline to get the counts.

For example, suppose you have a collection of users with different roles and you would like to calculate the distinct counts of the roles. You would need to run the following aggregate pipeline:

db.users.aggregate([
    { "$group": {
        "_id": { "$toLower": "$role" },
        "count": { "$sum": 1 }
    } },
    { "$group": {
        "_id": null,
        "counts": {
            "$push": { "k": "$_id", "v": "$count" }
        }
    } },
    { "$replaceRoot": {
        "newRoot": { "$arrayToObject": "$counts" }
    } }    
])

Example Output

{
    "user" : 67,
    "superuser" : 5,
    "admin" : 4,
    "moderator" : 12
}

What is the correct way to restore a deleted file from SVN?

With Tortoise SVN:

If you haven't committed your changes yet, you can do a revert on the parent folder where you deleted the file or directory.

If you have already committed the deleted file, then you can use the repository browser, change to the revision where the file still existed and then use the command Copy to... from the context menu. Enter the path to your working copy as the target and the deleted file will be copied from the repository to your working copy.

How do I include a JavaScript script file in Angular and call a function from that script?

In order to include a global library, eg jquery.js file in the scripts array from angular-cli.json (angular.json when using angular 6+):

"scripts": [
  "../node_modules/jquery/dist/jquery.js"
]

After this, restart ng serve if it is already started.

Python | change text color in shell

curses will allow you to use colors properly for the type of terminal that is being used.

TypeScript enum to object array

I'm surprised in a TypeScript thread no one gave valid TypeScript function with typing supported. Here's variation of @user8363 solution:

const isStringNumber = (value: string) => isNaN(Number(value)) === false;

function enumToArray<T extends {}>(givenEnum: T) {
  return (Object.keys(givenEnum).filter(isStringNumber) as (keyof T)[]).map(
    (key) => givenEnum[key]
  );
}

How to pad a string to a fixed length with spaces in Python?

I know this is a bit of an old question, but I've ended up making my own little class for it.

Might be useful to someone so I'll stick it up. I used a class variable, which is inherently persistent, to ensure sufficient whitespace was added to clear any old lines. See below:

class consolePrinter():
'''
Class to write to the console

Objective is to make it easy to write to console, with user able to 
overwrite previous line (or not)
'''
# -------------------------------------------------------------------------    
#Class variables
stringLen = 0    
# -------------------------------------------------------------------------    
    
# -------------------------------------------------------------------------
def writeline(stringIn, overwriteFlag=False):
    import sys
    #Get length of stringIn and update stringLen if needed
    if len(stringIn) > consolePrinter.stringLen:
        consolePrinter.stringLen = len(stringIn)+1
    
    ctrlString = "{:<"+str(consolePrinter.stringLen)+"}"
    if overwriteFlag:
        sys.stdout.write("\r" + ctrlString.format(stringIn))
    else:
        sys.stdout.write("\n" + stringIn)
    sys.stdout.flush()
    
    return

Which then is called via:

consolePrinter.writeline("text here", True) 

If you want to overwrite the previous line, or

consolePrinter.writeline("text here",False)

if you don't.

Note, for it to work right, all messages pushed to the console would need to be through consolePrinter.writeline.

Vertical align middle with Bootstrap responsive grid

Add !important rule to display: table of your .v-center class.

.v-center {
    display:table !important;
    border:2px solid gray;
    height:300px;
}

Your display property is being overridden by bootstrap to display: block.

Example

Create HTML table using Javascript

The problem is that if you try to write a <table> or a <tr> or <td> tag using JS every time you insert a new tag the browser will try to close it as it will think that there is an error on the code.

Instead of writing your table line by line, concatenate your table into a variable and insert it once created:

<script language="javascript" type="text/javascript">
<!--

var myArray    = new Array();
    myArray[0] = 1;
    myArray[1] = 2.218;
    myArray[2] = 33;
    myArray[3] = 114.94;
    myArray[4] = 5;
    myArray[5] = 33;
    myArray[6] = 114.980;
    myArray[7] = 5;

    var myTable= "<table><tr><td style='width: 100px; color: red;'>Col Head 1</td>";
    myTable+= "<td style='width: 100px; color: red; text-align: right;'>Col Head 2</td>";
    myTable+="<td style='width: 100px; color: red; text-align: right;'>Col Head 3</td></tr>";

    myTable+="<tr><td style='width: 100px;                   '>---------------</td>";
    myTable+="<td     style='width: 100px; text-align: right;'>---------------</td>";
    myTable+="<td     style='width: 100px; text-align: right;'>---------------</td></tr>";

  for (var i=0; i<8; i++) {
    myTable+="<tr><td style='width: 100px;'>Number " + i + " is:</td>";
    myArray[i] = myArray[i].toFixed(3);
    myTable+="<td style='width: 100px; text-align: right;'>" + myArray[i] + "</td>";
    myTable+="<td style='width: 100px; text-align: right;'>" + myArray[i] + "</td></tr>";
  }  
   myTable+="</table>";

 document.write( myTable);

//-->
</script> 

If your code is in an external JS file, in HTML create an element with an ID where you want your table to appear:

<div id="tablePrint"> </div>

And in JS instead of document.write(myTable) use the following code:

document.getElementById('tablePrint').innerHTML = myTable;

How to apply a CSS filter to a background image

pen

Abolishing the need for an extra element, along with making the content fit within the document flow rather than being fixed/absolute like other solutions.

Achieved using

_x000D_
_x000D_
.content {
  /* this is needed or the background will be offset by a few pixels at the top */
  overflow: auto;
  position: relative;
}

.content::before {
  content: "";
  position: fixed;
  left: 0;
  right: 0;
  z-index: -1;

  display: block;
  background-image: url('https://i.imgur.com/lL6tQfy.png');
  background-size:cover;
  width: 100%;
  height: 100%;

  -webkit-filter: blur(5px);
  -moz-filter: blur(5px);
  -o-filter: blur(5px);
  -ms-filter: blur(5px);
  filter: blur(5px);
}
_x000D_
<div class="content">
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
</div>
_x000D_
_x000D_
_x000D_

EDIT If you are interested in removing the white borders at the edges, use a width and height of 110% and a left and top of -5%. This will enlarge your backgrounds a tad - but there should be no solid colour bleeding in from the edges. Thanks Chad Fawcett for the suggestion.

_x000D_
_x000D_
.content {
  /* this is needed or the background will be offset by a few pixels at the top */
  overflow: auto;
  position: relative;
}

.content::before {
  content: "";
  position: fixed;
  top: -5%;
  left: -5%;
  right: -5%;
  z-index: -1;

  display: block;
  background-image: url('https://i.imgur.com/lL6tQfy.png');
  background-size:cover;
  width: 110%;
  height: 110%;

  -webkit-filter: blur(5px);
  -moz-filter: blur(5px);
  -o-filter: blur(5px);
  -ms-filter: blur(5px);
  filter: blur(5px);
}
_x000D_
<div class="content">
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
</div>
_x000D_
_x000D_
_x000D_

AES Encrypt and Decrypt

I was using CommonCrypto to generate Hash through the code of MihaelIsaev/HMAC.swift from Easy to use Swift implementation of CommonCrypto HMAC. This implementation is without using Bridging-Header, with creation of Module file.

Now to use AESEncrypt and Decrypt, I directly added the functions inside "extension String {" in HAMC.swift.

func aesEncrypt(key:String, iv:String, options:Int = kCCOptionPKCS7Padding) -> String? {
    if let keyData = key.dataUsingEncoding(NSUTF8StringEncoding),
        data = self.dataUsingEncoding(NSUTF8StringEncoding),
        cryptData    = NSMutableData(length: Int((data.length)) + kCCBlockSizeAES128) {

            let keyLength              = size_t(kCCKeySizeAES128)
            let operation: CCOperation = UInt32(kCCEncrypt)
            let algoritm:  CCAlgorithm = UInt32(kCCAlgorithmAES128)
            let options:   CCOptions   = UInt32(options)

            var numBytesEncrypted :size_t = 0

            let cryptStatus = CCCrypt(operation,
                algoritm,
                options,
                keyData.bytes, keyLength,
                iv,
                data.bytes, data.length,
                cryptData.mutableBytes, cryptData.length,
                &numBytesEncrypted)

            if UInt32(cryptStatus) == UInt32(kCCSuccess) {
                cryptData.length = Int(numBytesEncrypted)
                let base64cryptString = cryptData.base64EncodedStringWithOptions(.Encoding64CharacterLineLength)
                return base64cryptString
            }
            else {
                return nil
            }
    }
    return nil
}

func aesDecrypt(key:String, iv:String, options:Int = kCCOptionPKCS7Padding) -> String? {
    if let keyData = key.dataUsingEncoding(NSUTF8StringEncoding),
        data = NSData(base64EncodedString: self, options: .IgnoreUnknownCharacters),
        cryptData    = NSMutableData(length: Int((data.length)) + kCCBlockSizeAES128) {

            let keyLength              = size_t(kCCKeySizeAES128)
            let operation: CCOperation = UInt32(kCCDecrypt)
            let algoritm:  CCAlgorithm = UInt32(kCCAlgorithmAES128)
            let options:   CCOptions   = UInt32(options)

            var numBytesEncrypted :size_t = 0

            let cryptStatus = CCCrypt(operation,
                algoritm,
                options,
                keyData.bytes, keyLength,
                iv,
                data.bytes, data.length,
                cryptData.mutableBytes, cryptData.length,
                &numBytesEncrypted)

            if UInt32(cryptStatus) == UInt32(kCCSuccess) {
                cryptData.length = Int(numBytesEncrypted)
                let unencryptedMessage = String(data: cryptData, encoding:NSUTF8StringEncoding)
                return unencryptedMessage
            }
            else {
                return nil
            }
    }
    return nil
}

The functions were taken from RNCryptor. It was an easy addition in the hashing functions and in one single file "HMAC.swift", without using Bridging-header. I hope this will be useful for developers in swift requiring Hashing and AES Encryption/Decryption.

Example of using the AESDecrypt as under.

 let iv = "AA-salt-BBCCDD--" // should be of 16 characters.
 //here we are convert nsdata to String
 let encryptedString = String(data: dataFromURL, encoding: NSUTF8StringEncoding)
 //now we are decrypting
 if let decryptedString = encryptedString?.aesDecrypt("12345678901234567890123456789012", iv: iv) // 32 char pass key
 {                    
      // Your decryptedString
 }

How to fetch data from local JSON file on react native?

Take a look at this Github issue:

https://github.com/facebook/react-native/issues/231

They are trying to require non-JSON files, in particular JSON. There is no method of doing this right now, so you either have to use AsyncStorage as @CocoOS mentioned, or you could write a small native module to do what you need to do.

Multiple -and -or in PowerShell Where-Object statement

By wrapping your comparisons in {} in your first example you are creating ScriptBlocks; so the PowerShell interpreter views it as Where-Object { <ScriptBlock> -and <ScriptBlock> }. Since the -and operator operates on boolean values, PowerShell casts the ScriptBlocks to boolean values. In PowerShell anything that is not empty, zero or null is true. The statement then looks like Where-Object { $true -and $true } which is always true.

Instead of using {}, use parentheses ().

Also you want to use -eq instead of -match since match uses regex and will be true if the pattern is found anywhere in the string (try: 'xlsx' -match 'xls').

Invoke-Command -computername SERVERNAME { 
    Get-ChildItem -path E:\dfsroots\datastore2\public | 
        Where-Object {($_.extension -eq ".xls" -or $_.extension -eq ".xlk") -and ($_.creationtime -ge "06/01/2014")}
}

A better option is to filter the extensions at the Get-ChildItem command.

Invoke-Command -computername SERVERNAME { 
    Get-ChildItem -path E:\dfsroots\datastore2\public\* -Include *.xls, *.xlk | 
        Where-Object {$_.creationtime -ge "06/01/2014"}
}

How to gracefully handle the SIGKILL signal in Java

There is one way to react to a kill -9: that is to have a separate process that monitors the process being killed and cleans up after it if necessary. This would probably involve IPC and would be quite a bit of work, and you can still override it by killing both processes at the same time. I assume it will not be worth the trouble in most cases.

Whoever kills a process with -9 should theoretically know what he/she is doing and that it may leave things in an inconsistent state.

How to convert DOS/Windows newline (CRLF) to Unix newline (LF) in a Bash script?

tr -d "\r" < file

take a look here for examples using sed:

# IN UNIX ENVIRONMENT: convert DOS newlines (CR/LF) to Unix format.
sed 's/.$//'               # assumes that all lines end with CR/LF
sed 's/^M$//'              # in bash/tcsh, press Ctrl-V then Ctrl-M
sed 's/\x0D$//'            # works on ssed, gsed 3.02.80 or higher

# IN UNIX ENVIRONMENT: convert Unix newlines (LF) to DOS format.
sed "s/$/`echo -e \\\r`/"            # command line under ksh
sed 's/$'"/`echo \\\r`/"             # command line under bash
sed "s/$/`echo \\\r`/"               # command line under zsh
sed 's/$/\r/'                        # gsed 3.02.80 or higher

Use sed -i for in-place conversion e.g. sed -i 's/..../' file.

'Connect-MsolService' is not recognized as the name of a cmdlet

All links to the Azure Active Directory Connection page now seem to be invalid.

I had an older version of Azure AD installed too, this is what worked for me. Install this.

Run these in an elevated PS session:

uninstall-module AzureAD  # this may or may not be needed
install-module AzureAD
install-module AzureADPreview
install-module MSOnline

I was then able to log in and run what I needed.

Twitter Bootstrap Tabs: Go to Specific Tab on Page Reload or Hyperlink

@flynfish + @Ztyx solution that I use for nested tabs:

    handleTabLinks();

    function handleTabLinks() {
        if(window.location.hash == '') {
            window.location.hash = window.location.hash + '#_';
        }
        var hash = window.location.hash.split('#')[1];
        var prefix = '_';
        var hpieces = hash.split('/');
        for (var i=0;i<hpieces.length;i++) {
            var domelid = hpieces[i].replace(prefix,'');
            var domitem = $('a[href=#' + domelid + '][data-toggle=tab]');
            if (domitem.length > 0) {
                domitem.tab('show');
            }
        }
        $('a[data-toggle=tab]').on('shown', function (e) {
            if ($(this).hasClass('nested')) {
                var nested = window.location.hash.split('/');
                window.location.hash = nested[0] + '/' + e.target.hash.split('#')[1];
            } else {
                window.location.hash = e.target.hash.replace('#', '#' + prefix);
            }
        });
    }

childrens should have class="nested"

html select option SELECTED

You're missing quotes for $_GET['sel'] - fixing this might help solving your issue sooner :)

When is it acceptable to call GC.Collect?

There are some situations where it is better safe than sorry.

Here is one situation.

It is possible to author an unmanaged DLL in C# using IL rewrites (because there are situations where this is necessary).

Now suppose, for example, the DLL creates an array of bytes at the class level - because many of the exported functions need access to such. What happens when the DLL is unloaded? Is the garbage collector automatically called at that point? I don't know, but being an unmanaged DLL it is entirely possible the GC isn't called. And it would be a big problem if it wasn't called. When the DLL is unloaded so too would be the garbage collector - so who is going to be responsible for collecting any possible garbage and how would they do it? Better to employ C#'s garbage collector. Have a cleanup function (available to the DLL client) where the class level variables are set to null and the garbage collector called.

Better safe than sorry.

Which characters are valid in CSS class names/selectors?

For those looking for a workaround, you can use an attribute selector, for instance, if your class begins with a number. Change:

.000000-8{background:url(../../images/common/000000-0.8.png);} /* DOESN'T WORK!! */

to this:

[class="000000-8"]{background:url(../../images/common/000000-0.8.png);} /* WORKS :) */

Also, if there are multiple classes, you will need to specify them in selector I think.

Sources:

  1. https://benfrain.com/when-and-where-you-can-use-numbers-in-id-and-class-names/
  2. Is there a workaround to make CSS classes with names that start with numbers valid?

How can I copy data from one column to another in the same table?

UPDATE table_name SET
    destination_column_name=orig_column_name
WHERE condition_if_necessary

Could not find the main class, program will exit

Ha, I found what the problem was. I made my program using jdk1.7, but I had jre6 installed. I went and upgraded to jre7, and now it works fine :)

The

java -jar jarname.jar

line was working in the command prompt because my java path was set to the jdk folder.

$rootScope.$broadcast vs. $scope.$emit

tl;dr (this tl;dr is from @sp00m's answer below)

$emit dispatches an event upwards ... $broadcast dispatches an event downwards

Detailed explanation

$rootScope.$emit only lets other $rootScope listeners catch it. This is good when you don't want every $scope to get it. Mostly a high level communication. Think of it as adults talking to each other in a room so the kids can't hear them.

$rootScope.$broadcast is a method that lets pretty much everything hear it. This would be the equivalent of parents yelling that dinner is ready so everyone in the house hears it.

$scope.$emit is when you want that $scope and all its parents and $rootScope to hear the event. This is a child whining to their parents at home (but not at a grocery store where other kids can hear).

$scope.$broadcast is for the $scope itself and its children. This is a child whispering to its stuffed animals so their parents can't hear.

How to update Ruby Version 2.0.0 to the latest version in Mac OSX Yosemite?

In case anyone gets the same error I did: “Requirements installation failed with status: 1.” here's what to do:

Install Homebrew (for some reason might not work automatically) with this command:

ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

Then proceed to install rvm again using

curl -sSL https://get.rvm.io | bash -s stable --ruby

Quit and reopen Terminal and then:

rvm install 2.2
rvm use 2.2 --default

Batch file to delete folders older than 10 days in Windows 7

Adapted from this answer to a very similar question:

FORFILES /S /D -10 /C "cmd /c IF @isdir == TRUE rd /S /Q @path"

You should run this command from within your d:\study folder. It will delete all subfolders which are older than 10 days.

The /S /Q after the rd makes it delete folders even if they are not empty, without prompting.

I suggest you put the above command into a .bat file, and save it as d:\study\cleanup.bat.

Differences between Microsoft .NET 4.0 full Framework and Client Profile

You should deploy "Client Profile" instead of "Full Framework" inside a corporation mostly in one case only: you want explicitly deny some .NET features are running on the client computers. The only real case is denying of ASP.NET on the client machines of the corporation, for example, because of security reasons or the existing corporate policy.

Saving of less than 8 MB on client computer can not be a serious reason of "Client Profile" deployment in a corporation. The risk of the necessity of the deployment of the "Full Framework" later in the corporation is higher than costs of 8 MB per client.

What resources are shared between threads?

Threads share the code and data segments and the heap, but they don't share the stack.

Cross compile Go on OSX?

With Go 1.5 they seem to have improved the cross compilation process, meaning it is built in now. No ./make.bash-ing or brew-ing required. The process is described here but for the TLDR-ers (like me) out there: you just set the GOOS and the GOARCH environment variables and run the go build.

For the even lazier copy-pasters (like me) out there, do something like this if you're on a *nix system:

env GOOS=linux GOARCH=arm go build -v github.com/path/to/your/app

You even learned the env trick, which let you set environment variables for that command only, completely free of charge.

Listing available com ports with Python

one line solution with pySerial package.

python -m serial.tools.list_ports

How can I get a character in a string by index?

string s = "hello";
char c = s[1];
// now c == 'e'

See also Substring, to return more than one character.

Rounding a double value to x number of decimal places in swift

I found this wondering if it is possible to correct a user's input. That is if they enter three decimals instead of two for a dollar amount. Say 1.111 instead of 1.11 can you fix it by rounding? The answer for many reasons is no! With money anything over i.e. 0.001 would eventually cause problems in a real checkbook.

Here is a function to check the users input for too many values after the period. But which will allow 1., 1.1 and 1.11.

It is assumed that the value has already been checked for successful conversion from a String to a Double.

//func need to be where transactionAmount.text is in scope

func checkDoublesForOnlyTwoDecimalsOrLess()->Bool{


    var theTransactionCharacterMinusThree: Character = "A"
    var theTransactionCharacterMinusTwo: Character = "A"
    var theTransactionCharacterMinusOne: Character = "A"

    var result = false

    var periodCharacter:Character = "."


    var myCopyString = transactionAmount.text!

    if myCopyString.containsString(".") {

         if( myCopyString.characters.count >= 3){
                        theTransactionCharacterMinusThree = myCopyString[myCopyString.endIndex.advancedBy(-3)]
         }

        if( myCopyString.characters.count >= 2){
            theTransactionCharacterMinusTwo = myCopyString[myCopyString.endIndex.advancedBy(-2)]
        }

        if( myCopyString.characters.count > 1){
            theTransactionCharacterMinusOne = myCopyString[myCopyString.endIndex.advancedBy(-1)]
        }


          if  theTransactionCharacterMinusThree  == periodCharacter {

                            result = true
          }


        if theTransactionCharacterMinusTwo == periodCharacter {

            result = true
        }



        if theTransactionCharacterMinusOne == periodCharacter {

            result = true
        }

    }else {

        //if there is no period and it is a valid double it is good          
        result = true

    }

    return result


}

Bootstrap navbar Active State not working

$(document).ready(function() {
            
   var url = window.location.href;
            
   $('a[href*="'+url+'"]').addClass("active");
            
});

How to close Browser Tab After Submitting a Form?

Remove onsubmit from the form tag. Change this:

<input type="submit" value="submit" />

To:

<input type="submit" value="submit" name='btnSub' />

And write this:

if(isset($_POST['btnSub']))
    echo "<script>window.close();</script>";

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

Another option is that you have a duplicate entry in INSTALLED_APPS. That threw this error for two different apps I tested. Apparently it's not something Django checks for, but then who's silly enough to put the same app in the list twice. Me, that's who.

Java HttpRequest JSON & Response Handling

The simplest way is using libraries like google-http-java-client but if you want parse the JSON response by yourself you can do that in a multiple ways, you can use org.json, json-simple, Gson, minimal-json, jackson-mapper-asl (from 1.x)... etc

A set of simple examples:

Using Gson:

import java.io.IOException;

import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.util.EntityUtils;

public class Gson {

    public static void main(String[] args) {
    }

    public HttpResponse http(String url, String body) {

        try (CloseableHttpClient httpClient = HttpClientBuilder.create().build()) {
            HttpPost request = new HttpPost(url);
            StringEntity params = new StringEntity(body);
            request.addHeader("content-type", "application/json");
            request.setEntity(params);
            HttpResponse result = httpClient.execute(request);
            String json = EntityUtils.toString(result.getEntity(), "UTF-8");

            com.google.gson.Gson gson = new com.google.gson.Gson();
            Response respuesta = gson.fromJson(json, Response.class);

            System.out.println(respuesta.getExample());
            System.out.println(respuesta.getFr());

        } catch (IOException ex) {
        }
        return null;
    }

    public class Response{

        private String example;
        private String fr;

        public String getExample() {
            return example;
        }
        public void setExample(String example) {
            this.example = example;
        }
        public String getFr() {
            return fr;
        }
        public void setFr(String fr) {
            this.fr = fr;
        }
    }
}

Using json-simple:

import java.io.IOException;

import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.util.EntityUtils;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;

public class JsonSimple {

    public static void main(String[] args) {

    }

    public HttpResponse http(String url, String body) {

        try (CloseableHttpClient httpClient = HttpClientBuilder.create().build()) {
            HttpPost request = new HttpPost(url);
            StringEntity params = new StringEntity(body);
            request.addHeader("content-type", "application/json");
            request.setEntity(params);
            HttpResponse result = httpClient.execute(request);

            String json = EntityUtils.toString(result.getEntity(), "UTF-8");
            try {
                JSONParser parser = new JSONParser();
                Object resultObject = parser.parse(json);

                if (resultObject instanceof JSONArray) {
                    JSONArray array=(JSONArray)resultObject;
                    for (Object object : array) {
                        JSONObject obj =(JSONObject)object;
                        System.out.println(obj.get("example"));
                        System.out.println(obj.get("fr"));
                    }

                }else if (resultObject instanceof JSONObject) {
                    JSONObject obj =(JSONObject)resultObject;
                    System.out.println(obj.get("example"));
                    System.out.println(obj.get("fr"));
                }

            } catch (Exception e) {
                // TODO: handle exception
            }

        } catch (IOException ex) {
        }
        return null;
    }
}

etc...

Set title background color

This thread will get you started with building your own title bar in a xml file and using it in your activities

Edit

Here is a brief summary of the content of the link above - This is just to set the color of the text and the background of the title bar - no resizing, no buttons, just the simpliest sample

res/layout/mytitle.xml - This is the view that will represent the title bar

<?xml version="1.0" encoding="utf-8"?>
<TextView
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:id="@+id/myTitle"
  android:text="This is my new title"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:textColor="@color/titletextcolor"
   />

res/values/themes.xml - We want to keep the default android theme and just need to change the background color of the title background. So we create a theme that inherits the default theme and set the background style to our own style.

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <style name="customTheme" parent="android:Theme"> 
        <item name="android:windowTitleBackgroundStyle">@style/WindowTitleBackground</item>   
    </style> 
</resources>

res/values/styles.xml - This is where we set the theme to use the color we want for the title background

<?xml version="1.0" encoding="utf-8"?>
<resources> 
   <style name="WindowTitleBackground">     
        <item name="android:background">@color/titlebackgroundcolor</item>                   
    </style>
</resources>

res/values/colors.xml - Set here the color you want

<?xml version="1.0" encoding="utf-8"?>
<resources>   
    <color name="titlebackgroundcolor">#3232CD</color>
    <color name="titletextcolor">#FFFF00</color>
</resources>

In the AndroidMANIFEST.xml, set the theme attribute either in the application (for the whole application) or in the activity (only this activity) tags

<activity android:name=".CustomTitleBar" android:theme="@style/customTheme" ...

From the Activity (called CustomTitleBar) :

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

        requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
        setContentView(R.layout.main);
        getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE, R.layout.mytitle);

}

Laravel: PDOException: could not find driver

For me, php.ini was OK, but I needed to restart php artisan serve.

select2 changing items dynamically

In my project I use following code:

$('#attribute').select2();
$('#attribute').bind('change', function(){
    var $options = $();
    for (var i in data) {
        $options = $options.add(
            $('<option>').attr('value', data[i].id).html(data[i].text)
        );
    }
    $('#value').html($options).trigger('change');
});

Try to comment out the select2 part. The rest of the code will still work.

Is there a keyboard shortcut (hotkey) to open Terminal in macOS?

iTerm2 - an alternative to Terminal - has an option to use configurable system-wide hotkey to show/hide (initially set to Alt+Space, disabled by default)

How do I make a fixed size formatted string in python?

Sure, use the .format method. E.g.,

print('{:10s} {:3d}  {:7.2f}'.format('xxx', 123, 98))
print('{:10s} {:3d}  {:7.2f}'.format('yyyy', 3, 1.0))
print('{:10s} {:3d}  {:7.2f}'.format('zz', 42, 123.34))

will print

xxx        123    98.00
yyyy         3     1.00
zz          42   123.34

You can adjust the field sizes as desired. Note that .format works independently of print to format a string. I just used print to display the strings. Brief explanation:

10s format a string with 10 spaces, left justified by default

3d format an integer reserving 3 spaces, right justified by default

7.2f format a float, reserving 7 spaces, 2 after the decimal point, right justfied by default.

There are many additional options to position/format strings (padding, left/right justify etc), String Formatting Operations will provide more information.

Update for f-string mode. E.g.,

text, number, other_number = 'xxx', 123, 98
print(f'{text:10} {number:3d}  {other_number:7.2f}')

For right alignment

print(f'{text:>10} {number:3d}  {other_number:7.2f}')

How do I find where JDK is installed on my windows machine?

On macOS, run:

cd /tmp && echo 'public class Main {public static void main(String[] args) {System.out.println(System.getProperty("java.home"));}}' > Main.java && javac Main.java && java Main

On my machine, this prints:

/Library/Java/JavaVirtualMachines/jdk-9.0.4.jdk/Contents/Home

Note that running which java does not show the JDK location, because the java command is instead part of JavaVM.framework, which wraps the real JDK:

$ which java
/usr/bin/java
/private/tmp
$ ls -l /usr/bin/java
lrwxr-xr-x  1 root  wheel  74 14 Nov 17:37 /usr/bin/java -> /System/Library/Frameworks/JavaVM.framework/Versions/Current/Commands/java

Check if table exists without using "select from"

You can query the INFORMATION_SCHEMA tables system view:

SELECT table_name
FROM information_schema.tables
WHERE table_schema = 'databasename'
AND table_name = 'testtable';

If no rows returned, then the table doesn't exist.

Save a file in json format using Notepad++

Just show file name extension from Windows Explorer, after applying the below steps, create a new file, and type your extension as .json

Open Folder Options by clicking the Start button Picture of the Start button, clicking Control Panel, clicking Appearance and Personalization, and then clicking Folder Options.

Click the View tab, and then, under Advanced settings, clear the Hide extensions for known file types check box, and then click OK

Reference

How to calculate time difference in java?

import java.text.SimpleDateFormat;
import java.util.Date;
public class Main {
public static void main(String[] args) throws Exception{
    String time1 = "12:00:00";
    String time2 = "12:01:00";
    SimpleDateFormat format = new SimpleDateFormat("HH:mm:ss");
    Date date1 = format.parse(time1);
    Date date2 = format.parse(time2);
    long difference = date2.getTime() - date1.getTime();
    System.out.println(difference/1000);
}}

throws exception handles parsing exceptions

Clearing the terminal screen?

It's not possible to clear the Serial Monitor window based on incoming serial data.

I can think of a couple of options, the simplest (and cheatiest) is to use println() with a fixed width string that you've generated that contains your sensor data.

The Arduino IDE's Serial Monitor's Autoscroll checkbox means if you persistently send the fixed width string (with 500ms delay perhaps) this will give the impression that it's updating once it gets to the bottom and starts scrolling. You could also shrink the height of the window to make it look like it only has one line.

To accomplish a fixed width string that's suitable for serial println() you'll need functions to convert your sensor values to strings, as well as pad/trim them to a persistent size. Then concatenate the values together (including separators if it makes the data easier to read)

An output of something similar to this is what i'm hinting at:

| 1.0 | 1.1 | 1.2 | 1.3 | 1.4 | 1.5 | 1.6 | 1.7 | 1.8 |

All things considered, this isn't a great solution but it would get you a result.

A far smarter idea is to build another program outside of Arduino and it's IDE that listens to the com port for sensor values sent from the Arduino. Your Arduino program will need to send a message your external program can unambiguously interpret, something like 1=0.5; where 1 = sensor ID and 0.5 = sensor value. The external program would then keep these values (1 for each sensor). The external program can then display this information in whatever way you'd like, a nice console output would be relatively easy to achieve :-)

C# has .NET's serialport class which is a pleasure to use. (most of the time!)

Python has a module called pyserial, which is also easy great.

Either language will give you much greater control over console output, should you choose to proceed this way.

How to regex in a MySQL query

I think you can use REGEXP instead of LIKE

SELECT trecord FROM `tbl` WHERE (trecord REGEXP '^ALA[0-9]')

How to test Spring Data repositories?

If you're using Spring Boot, you can simply use @SpringBootTest to load in your ApplicationContext (which is what your stacktrace is barking at you about). This allows you to autowire in your spring-data repositories. Be sure to add @RunWith(SpringRunner.class) so the spring-specific annotations are picked up:

@RunWith(SpringRunner.class)
@SpringBootTest
public class OrphanManagementTest {

  @Autowired
  private UserRepository userRepository;

  @Test
  public void saveTest() {
    User user = new User("Tom");
    userRepository.save(user);
    Assert.assertNotNull(userRepository.findOne("Tom"));
  }
}

You can read more about testing in spring boot in their docs.

Options for embedding Chromium instead of IE WebBrowser control with WPF/C#

You've already listed the most notable solutions for embedding Chromium (CEF, Chrome Frame, Awesomium). There aren't any more projects that matter.

There is still the Berkelium project (see Berkelium Sharp and Berkelium Managed), but it emebeds an old version of Chromium.

CEF is your best bet - it's fully open source and frequently updated. It's the only option that allows you to embed the latest version of Chromium. Now that Per Lundberg is actively working on porting CEF 3 to CefSharp, this is the best option for the future. There is also Xilium.CefGlue, but this one provides a low level API for CEF, it binds to the C API of CEF. CefSharp on the other hand binds to the C++ API of CEF.

Adobe is not the only major player using CEF, see other notable applications using CEF on the CEF wikipedia page.

Updating Chrome Frame is pointless since the project has been retired.

How do I check if the Java JDK is installed on Mac?

Below command worked out pretty good:

javac -version

I also manually verified by navigating to the Java Folder on my Mac

/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk

How to convert "0" and "1" to false and true

My solution (vb.net):

Private Function ConvertToBoolean(p1 As Object) As Boolean
    If p1 Is Nothing Then Return False
    If IsDBNull(p1) Then Return False
    If p1.ToString = "1" Then Return True
    If p1.ToString.ToLower = "true" Then Return True
    Return False
End Function

What are the best JVM settings for Eclipse?

Here's my own setting for my Eclipse running on i7 2630M 16GB RAM laptop, this setting has been using for a week, without a single crashing, and Eclipse 3.7 is running smoothly.

-startup
plugins/org.eclipse.equinox.launcher_1.2.0.v20110502.jar
--launcher.library
plugins/org.eclipse.equinox.launcher.win32.win32.x86_64_1.1.100.v20110502
-product
org.eclipse.epp.package.jee.product
--launcher.defaultAction
openFile
--launcher.XXMaxPermSize
256M
-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
256m
--launcher.defaultAction
openFile
-vmargs
-Dosgi.requiredJavaVersion=1.5
-Xms1024m
-Xmx4096m 
-XX:MaxPermSize=256m

Calculations: For Win 7 x64

  • Xms = Physical Memory / 16
  • Xmx = Physical Memory / 4
  • MaxPermSize = Same as default value, which is 256m

ORA-00918: column ambiguously defined in SELECT *

You can also see this error when selecting for a union where corresponding columns can be null.

select * from (select D.dept_no, D.nullable_comment
                  from dept D
       union
               select R.dept_no, NULL
                 from redundant_dept R
)

This apparently confuses the parser, a solution is to assign a column alias to the always null column.

select * from (select D.dept_no, D.comment
                  from dept D
       union
               select R.dept_no, NULL "nullable_comment"
                 from redundant_dept R
)

The alias does not have to be the same as the corresponding column, but the column heading in the result is driven by the first query from among the union members, so it's probably a good practice.

How to define a variable in a Dockerfile?

To my knowledge, only ENV allows that, as mentioned in "Environment replacement"

Environment variables (declared with the ENV statement) can also be used in certain instructions as variables to be interpreted by the Dockerfile.

They have to be environment variables in order to be redeclared in each new containers created for each line of the Dockerfile by docker build.

In other words, those variables aren't interpreted directly in a Dockerfile, but in a container created for a Dockerfile line, hence the use of environment variable.


This day, I use both ARG (docker 1.10+, and docker build --build-arg var=value) and ENV.
Using ARG alone means your variable is visible at build time, not at runtime.

My Dockerfile usually has:

ARG var
ENV var=${var}

In your case, ARG is enough: I use it typically for setting http_proxy variable, that docker build needs for accessing internet at build time.

How to search a specific value in all tables (PostgreSQL)?

And if someone think it could help. Here is @Daniel Vérité's function, with another param that accept names of columns that can be used in search. This way it decrease the time of processing. At least in my test it reduced a lot.

CREATE OR REPLACE FUNCTION search_columns(
    needle text,
    haystack_columns name[] default '{}',
    haystack_tables name[] default '{}',
    haystack_schema name[] default '{public}'
)
RETURNS table(schemaname text, tablename text, columnname text, rowctid text)
AS $$
begin
  FOR schemaname,tablename,columnname IN
      SELECT c.table_schema,c.table_name,c.column_name
      FROM information_schema.columns c
      JOIN information_schema.tables t ON
        (t.table_name=c.table_name AND t.table_schema=c.table_schema)
      WHERE (c.table_name=ANY(haystack_tables) OR haystack_tables='{}')
        AND c.table_schema=ANY(haystack_schema)
        AND (c.column_name=ANY(haystack_columns) OR haystack_columns='{}')
        AND t.table_type='BASE TABLE'
  LOOP
    EXECUTE format('SELECT ctid FROM %I.%I WHERE cast(%I as text)=%L',
       schemaname,
       tablename,
       columnname,
       needle
    ) INTO rowctid;
    IF rowctid is not null THEN
      RETURN NEXT;
    END IF;
 END LOOP;
END;
$$ language plpgsql;

Bellow is an example of usage of the search_function created above.

SELECT * FROM search_columns('86192700'
    , array(SELECT DISTINCT a.column_name::name FROM information_schema.columns AS a
            INNER JOIN information_schema.tables as b ON (b.table_catalog = a.table_catalog AND b.table_schema = a.table_schema AND b.table_name = a.table_name)
        WHERE 
            a.column_name iLIKE '%cep%' 
            AND b.table_type = 'BASE TABLE'
            AND b.table_schema = 'public'
    )

    , array(SELECT b.table_name::name FROM information_schema.columns AS a
            INNER JOIN information_schema.tables as b ON (b.table_catalog = a.table_catalog AND b.table_schema = a.table_schema AND b.table_name = a.table_name)
        WHERE 
            a.column_name iLIKE '%cep%' 
            AND b.table_type = 'BASE TABLE'
            AND b.table_schema = 'public')
);

cannot download, $GOPATH not set

I am using vim to edit my .bashrc file but you code use a gui editor such as gedit.

Steps:

Kindly subsitute /path/to/golang/projects below with your actual path location where you will store your golang projects.

Open .bashrc file in vim that is vim ~/.bashrc. Then add below lines at the end of the file.

# Setup Golang Development Environment ::
export GOROOT=/usr/local/go
export PATH=$PATH:$GOROOT/bin
 
# Third party go libraries will live under "~/golib" directory
export GOPATH="$HOME/golib"
export PATH="$PATH:$GOPATH/bin"
 
# Where your golang project code lives
export GOPATH=$GOPATH:/path/to/golang/projects

Save the file and type source ~/.bashrc to refresh your terminal session. Now try getting a package e.g. go get github.com/pilu/fresh and check your ~/golib/bin directory it should have fresh package in it.

Navigate to your /path/to/golang/projects and create three folders in there i.e. bin,src and pkg

Now place your project folder inside /path/to/golang/projects/src e.g. /path/to/golang/projects/src/myfancygolangprojectand you should be good to go. Put all your golang codebase in there mate.

How to create Windows EventLog source from command line?

If someone is interested, it is also possible to create an event source manually by adding some registry values.

Save the following lines as a .reg file, then import it to registry by double clicking it:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\eventlog\Application\YOUR_EVENT_SOURCE_NAME_GOES_HERE]
"EventMessageFile"="C:\\Windows\\Microsoft.NET\\Framework64\\v4.0.30319\\EventLogMessages.dll"
"TypesSupported"=dword:00000007

This creates an event source named YOUR_EVENT_SOURCE_NAME_GOES_HERE.

How to list only the file names that changed between two commits?

It seems that no one has mentioned the switch --stat:

$ git diff --stat HEAD~5 HEAD
 .../java/org/apache/calcite/rex/RexSimplify.java   | 50 +++++++++++++++++-----
 .../apache/calcite/sql/fun/SqlTrimFunction.java    |  2 +-
 .../apache/calcite/sql2rel/SqlToRelConverter.java  | 16 +++++++
 .../org/apache/calcite/util/SaffronProperties.java | 19 ++++----
 .../org/apache/calcite/test/RexProgramTest.java    | 24 +++++++++++
 .../apache/calcite/test/SqlToRelConverterTest.java |  8 ++++
 .../apache/calcite/test/SqlToRelConverterTest.xml  | 15 +++++++
 pom.xml                                            |  2 +-
 .../apache/calcite/adapter/spark/SparkRules.java   |  7 +--
 9 files changed, 117 insertions(+), 26 deletions(-)

There are also --numstat

$ git diff --numstat HEAD~5 HEAD
40      10      core/src/main/java/org/apache/calcite/rex/RexSimplify.java
1       1       core/src/main/java/org/apache/calcite/sql/fun/SqlTrimFunction.java
16      0       core/src/main/java/org/apache/calcite/sql2rel/SqlToRelConverter.java
8       11      core/src/main/java/org/apache/calcite/util/SaffronProperties.java
24      0       core/src/test/java/org/apache/calcite/test/RexProgramTest.java
8       0       core/src/test/java/org/apache/calcite/test/SqlToRelConverterTest.java
15      0       core/src/test/resources/org/apache/calcite/test/SqlToRelConverterTest.xml
1       1       pom.xml
4       3       spark/src/main/java/org/apache/calcite/adapter/spark/SparkRules.java

and --shortstat

$ git diff --shortstat HEAD~5 HEAD
9 files changed, 117 insertions(+), 26 deletions(-)

How to save to local storage using Flutter?

If you are in a situation where you wanna save a small value that you wanna refer later. then you should store your data as key-value data using shared_preferences

but if you want to store large data you should go with SQLITE

however you can always use firebase database which is available offline

Since we are talking about local storage you can always read and write files to the disk

Other solutions :

How to use if-else option in JSTL

you have to use this code:

with <%@ taglib prefix="c" uri="http://www.springframework.org/tags/form"%>

and

<c:select>
            <option value="RCV"
                ${records[0].getDirection() == 'RCV' ? 'selected="true"' : ''}>
                <spring:message code="dropdown.Incoming" text="dropdown.Incoming" />
            </option>
            <option value="SND"
                ${records[0].getDirection() == 'SND'? 'selected="true"' : ''}>
                <spring:message code="dropdown.Outgoing" text="dropdown.Outgoing" />
            </option>
        </c:select>

background:none vs background:transparent what is the difference?

There is no difference between them.

If you don't specify a value for any of the half-dozen properties that background is a shorthand for, then it is set to its default value. none and transparent are the defaults.

One explicitly sets the background-image to none and implicitly sets the background-color to transparent. The other is the other way around.

Where is the Microsoft.IdentityModel dll

In Windows 8.1 64bit, look under C:\Windows\ADFS

What languages are Windows, Mac OS X and Linux written in?

Windows c c++ 10% C# Perl Linux C MAC Obective c Android Java c++ Solaris c c++

I hope you get the answer.

Accessing all items in the JToken

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

Then you can call its something like this...

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

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

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

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

How do you list the primary key of a SQL Server table?

The system stored procedure sp_help will give you the information. Execute the following statement:

execute sp_help table_name

How can I get the value of a registry key from within a batch script?

This work for me with variable that contains spaces on Windows 7:

FOR /F "usebackq tokens=3*" %%A IN (`REG QUERY "HKEY_LOCAL_MACHINE\Software\SomeAPP" /v ValueName`) DO (
    set appdir=%%A %%B
    )
ECHO %appdir%

Variable A contains all data before first space, B - rest part of ValueName (including further spaces), so appdir = ValueName

How to directly move camera to current location in Google Maps Android API v2?

Just change moveCamera to animateCamera like below

Googlemap.animateCamera(CameraUpdateFactory.newLatLngZoom(locate, 16F))

Undefined reference to `sin`

I had the same problem, which went away after I listed my library last: gcc prog.c -lm

What does cmd /C mean?

The part you should be interested in is the /? part, which should solve most other questions you have with the tool.

Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

C:\>cmd /?
Starts a new instance of the Windows XP command interpreter

CMD [/A | /U] [/Q] [/D] [/E:ON | /E:OFF] [/F:ON | /F:OFF] [/V:ON | /V:OFF]
    [[/S] [/C | /K] string]

/C      Carries out the command specified by string and then terminates
/K      Carries out the command specified by string but remains
/S      Modifies the treatment of string after /C or /K (see below)
/Q      Turns echo off
/D      Disable execution of AutoRun commands from registry (see below)
/A      Causes the output of internal commands to a pipe or file to be ANSI
/U      Causes the output of internal commands to a pipe or file to be
        Unicode
/T:fg   Sets the foreground/background colors (see COLOR /? for more info)
/E:ON   Enable command extensions (see below)
/E:OFF  Disable command extensions (see below)
/F:ON   Enable file and directory name completion characters (see below)
/F:OFF  Disable file and directory name completion characters (see below)
/V:ON   Enable delayed environment variable expansion using ! as the
        delimiter. For example, /V:ON would allow !var! to expand the
        variable var at execution time.  The var syntax expands variables
        at input time, which is quite a different thing when inside of a FOR
        loop.
/V:OFF  Disable delayed environment expansion.

Markdown open a new window link

There is no such feature in markdown, however you can always use HTML inside markdown:

<a href="http://example.com/" target="_blank">example</a>

How to connect to LocalDb

To locate a DB from SQL Server management studio can be done through browse - in the connect to database screen

enter image description here

Also make sure a local database is installed during installation:

enter image description here

Submitting a form by pressing enter without a submit button

Try:

<input type="submit" style="position: absolute; left: -9999px"/>

That will push the button waaay to the left, out of the screen. The nice thing with this is, you'd get graceful degradation when CSS is disabled.

Update - Workaround for IE7

As suggested by Bryan Downing + with tabindex to prevent tab reach this button (by Ates Goral):

<input type="submit" 
       style="position: absolute; left: -9999px; width: 1px; height: 1px;"
       tabindex="-1" />

how to get javaScript event source element?

Your html should be like this:

<button onclick="doSomething" id="id_button">action</button>

And renaming your input-paramter to event like this

function doSomething(event){
    var source = event.target || event.srcElement;
    console.log(source);
}

would solve your problem.

As a side note, I'd suggest taking a look at jQuery and unobtrusive javascript

HTML5 required attribute seems not working

My answer is too late, but it can help others.

I had the same problem, even when I used a form tag.

I solved it by declaring Meta Charset in the header of the page:

_x000D_
_x000D_
<meta charset = "UTF-8" />
_x000D_
_x000D_
_x000D_

How do you pass view parameters when navigating from an action in JSF2?

You can do it using Primefaces like this :

<p:button 
      outcome="/page2.xhtml?faces-redirect=true&amp;id=#{myBean.id}">
</p:button>

Rails: How to list database tables/objects using the Rails console?

Its a start, it can list:

models = Dir.new("#{RAILS_ROOT}/app/models").entries

Looking some more...

phpMyAdmin - config.inc.php configuration?

Do Ctrl+alt+t and then:

  1. sudo chmod 777 /opt/lampp/phpmyadmin/config.inc.php

  2. open config.inc.php

  3. test

    1. change config to cookie
      $cfg['Servers'][$i]['auth_type'] = 'config';
    2. donot change this
      $cfg['Servers'][$i]['user'] = 'root';
    3. change '' to 'root'
      $cfg['Servers'][$i]['password'] = '';
  4. save config.inc.php

  5. sudo chmod 644 /opt/lampp/phpmyadmin/config.inc.php

  6. restart the xampp and check phpmyadmin

If it works i think i am glad to help you!!!

$(document).ready(function(){ Uncaught ReferenceError: $ is not defined

Remember that you must first load jquery script and then the script js

<script type="text/javascript" src="http://code.jquery.com/jquery-2.2.4.min.js"></script>
<script type="text/javascript" src="example.js"></script>

Html is read sequentially!

How to check if the string is empty?

When you are reading file by lines and want to determine, which line is empty, make sure you will use .strip(), because there is new line character in "empty" line:

lines = open("my_file.log", "r").readlines()

for line in lines:
    if not line.strip():
        continue

    # your code for non-empty lines

make: *** [ ] Error 1 error

I got the same thing. Running "make" and it fails with just this message.

% make
make: *** [all] Error 1

This was caused by a command in a rule terminates with non-zero exit status. E.g. imagine the following (stupid) Makefile:

all:
       @false
       echo "hello"

This would fail (without printing "hello") with the above message since false terminates with exit status 1.

In my case, I was trying to be clever and make a backup of a file before processing it (so that I could compare the newly generated file with my previous one). I did this by having a in my Make rule that looked like this:

@[ -e $@ ] && mv $@ [email protected]

...not realizing that if the target file does not exist, then the above construction will exit (without running the mv command) with exit status 1, and thus any subsequent commands in that rule failed to run. Rewriting my faulty line to:

@if [ -e $@ ]; then mv $@ [email protected]; fi

Solved my problem.

How to do URL decoding in Java?

public String decodeString(String URL)
    {

    String urlString="";
    try {
        urlString = URLDecoder.decode(URL,"UTF-8");
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block

        }

        return urlString;

    }

Pad with leading zeros

You can do this with a string datatype. Use the PadLeft method:

var myString = "1";
myString = myString.PadLeft(myString.Length + 5, '0');

000001

IIS Express Windows Authentication

Building upon the answer from booij boy, check if you checked the "windows authentication" feature in Control Panel -> Programs -> Turn windows features on or of -> Internet Information Services -> World Wide Web Services -> Security

Also, there seems to be a big difference when using firefox or internet explorer. After enabeling the "windows authentication" it works for me but only in IE.

How to programmatically round corners and set random background colors

Total programmatic approach to set rounded corners and add random background color to a View. I have not tested the code, but you get the idea.

 GradientDrawable shape =  new GradientDrawable();
 shape.setCornerRadius( 8 );

 // add some color
 // You can add your random color generator here
 // and set color
 if (i % 2 == 0) {
  shape.setColor(Color.RED);
 } else {
  shape.setColor(Color.BLUE);
 }

 // now find your view and add background to it
 View view = (LinearLayout) findViewById( R.id.my_view );
 view.setBackground(shape);

Here we are using gradient drawable so that we can make use of GradientDrawable#setCornerRadius because ShapeDrawable DOES NOT provide any such method.

Delayed rendering of React components

render the child components not at once but after some delay .

The question says delay render but if it is ok to render but hide...

You can render the components from a map straight away but use css animation to delay them being shown.

@keyframes Jumpin {
 0% { opacity: 0; }
 50% { opacity: 0; }
 100% { opacity: 1; }
}
// Sass loop code
@for $i from 2 through 10 {
 .div .div:nth-child(#{$i}) {
  animation: Jumpin #{$i * 0.35}s cubic-bezier(.9,.03,.69,.22);
 }
}

The child divs now follow each other with a slight delay.

Can I underline text in an Android layout?

try this code

in XML

<resource>
 <string name="my_text"><![CDATA[This is an <u>underline</u>]]></string> 
</resources> 

in Code

TextView textView = (TextView) view.findViewById(R.id.textview);
textView.setText(Html.fromHtml(getString(R.string.my_text)));

Good Luck!

Python Save to file

file = open('Failed.py', 'w')
file.write('whatever')
file.close()

Here is a more pythonic version, which automatically closes the file, even if there was an exception in the wrapped block:

with open('Failed.py', 'w') as file:
    file.write('whatever')

byte array to pdf

You shouldn't be using the BinaryFormatter for this - that's for serializing .Net types to a binary file so they can be read back again as .Net types.

If it's stored in the database, hopefully, as a varbinary - then all you need to do is get the byte array from that (that will depend on your data access technology - EF and Linq to Sql, for example, will create a mapping that makes it trivial to get a byte array) and then write it to the file as you do in your last line of code.

With any luck - I'm hoping that fileContent here is the byte array? In which case you can just do

System.IO.File.WriteAllBytes("hello.pdf", fileContent);

Free easy way to draw graphs and charts in C++?

Cern's ROOT produces some pretty nice stuff, I use it to display Neural Network data a lot.

sys.stdin.readline() reads without prompt, returning 'nothing in between'

Simon's answer and Volcano's together explain what you're doing wrong, and Simon explains how you can fix it by redesigning your interface.

But if you really need to read 1 character, and then later read 1 line, you can do that. It's not trivial, and it's different on Windows vs. everything else.

There are actually three cases: a Unix tty, a Windows DOS prompt, or a regular file (redirected file/pipe) on either platform. And you have to handle them differently.

First, to check if stdin is a tty (both Windows and Unix varieties), you just call sys.stdin.isatty(). That part is cross-platform.

For the non-tty case, it's easy. It may actually just work. If it doesn't, you can just read from the unbuffered object underneath sys.stdin. In Python 3, this just means sys.stdin.buffer.raw.read(1) and sys.stdin.buffer.raw.readline(). However, this will get you encoded bytes, rather than strings, so you will need to call .decode(sys.stdin.decoding) on the results; you can wrap that all up in a function.

For the tty case on Windows, however, input will still be line buffered even on the raw buffer. The only way around this is to use the Console I/O functions instead of normal file I/O. So, instead of stdin.read(1), you do msvcrt.getwch().

For the tty case on Unix, you have to set the terminal to raw mode instead of the usual line-discipline mode. Once you do that, you can use the same sys.stdin.buffer.read(1), etc., and it will just work. If you're willing to do that permanently (until the end of your script), it's easy, with the tty.setraw function. If you want to return to line-discipline mode later, you'll need to use the termios module. This looks scary, but if you just stash the results of termios.tcgetattr(sys.stdin.fileno()) before calling setraw, then do termios.tcsetattr(sys.stdin.fileno(), TCSAFLUSH, stash), you don't have to learn what all those fiddly bits mean.

On both platforms, mixing console I/O and raw terminal mode is painful. You definitely can't use the sys.stdin buffer if you've ever done any console/raw reading; you can only use sys.stdin.buffer.raw. You could always replace readline by reading character by character until you get a newline… but if the user tries to edit his entry by using backspace, arrows, emacs-style command keys, etc., you're going to get all those as raw keypresses, which you don't want to deal with.

How to execute only one test spec with angular-cli

Adding to this for people like me who were searching for a way to run a single spec in Angular and found this SO.

According to the latest Angular docs (v9.0.6 at time of writing), the ng test command has an --include option where you can specify a directory of *.spec.(ts|tsx) files or just a single .spec.(ts|tsx) file itself.

https://angular.io/cli/test

Get current domain

$_SERVER['HTTP_HOST'] 

//to get the domain

$protocol=strpos(strtolower($_SERVER['SERVER_PROTOCOL']),'https') === FALSE ? 'http' : 'https';
$domainLink=$protocol.'://'.$_SERVER['HTTP_HOST'];

//domain with protocol

$url=$protocol.'://'.$_SERVER['HTTP_HOST'].'?'.$_SERVER['QUERY_STRING'];

//protocol,domain,queryString total **As the $_SERVER['SERVER_NAME'] is not reliable for multi domain hosting!

Postgres integer arrays as parameters?

Full Coding Structure

postgresql function

CREATE OR REPLACE FUNCTION admin.usp_itemdisplayid_byitemhead_select(
    item_head_list int[])
    RETURNS TABLE(item_display_id integer) 
    LANGUAGE 'sql'

    COST 100
    VOLATILE 
    ROWS 1000
    
AS $BODY$ 
        SELECT vii.item_display_id from admin.view_item_information as vii
where vii.item_head_id = ANY(item_head_list);
    $BODY$;

Model

public class CampaignCreator
    {
        public int item_display_id { get; set; }
        public List<int> pitem_head_id { get; set; }
    }

.NET CORE function

DynamicParameters _parameter = new DynamicParameters();
                _parameter.Add("@item_head_list",obj.pitem_head_id);
                
                string sql = "select * from admin.usp_itemdisplayid_byitemhead_select(@item_head_list)";
                response.data = await _connection.QueryAsync<CampaignCreator>(sql, _parameter);

How to fix System.NullReferenceException: Object reference not set to an instance of an object

If the problem is 100% here

EffectSelectorForm effectSelectorForm = new EffectSelectorForm(Effects);

There's only one possible explanation: property/variable "Effects" is not initialized properly... Debug your code to see what you pass to your objects.

EDIT after several hours

There were some problems:

  • MEF attribute [Import] didn't work as expected, so we replaced it for the time being with a manually populated List<>. While the collection was null, it was causing exceptions later in the code, when the method tried to get the type of the selected item and there was none.

  • several event handlers weren't wired up to control events

Some problems are still present, but I believe OP's original problem has been fixed. Other problems are not related to this one.

Put text at bottom of div

Wrap the text in a span or similar and use the following CSS:

.your-div {
    position: relative;
}

.your-div span {
    position: absolute;
    bottom: 0;
    right: 0;
}

Illegal pattern character 'T' when parsing a date string to java.util.Date

There are two answers above up-to-now and they are both long (and tl;dr too short IMHO), so I write summary from my experience starting to use new java.time library (applicable as noted in other answers to Java version 8+). ISO 8601 sets standard way to write dates: YYYY-MM-DD so the format of date-time is only as below (could be 0, 3, 6 or 9 digits for milliseconds) and no formatting string necessary:

import java.time.Instant;
public static void main(String[] args) {
    String date="2010-10-02T12:23:23Z";
    try {
        Instant myDate = Instant.parse(date);
    } catch (ParseException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

I did not need it, but as getting year is in code from the question, then:
it is trickier, cannot be done from Instant directly, can be done via Calendar in way of questions Get integer value of the current year in Java and Converting java.time to Calendar but IMHO as format is fixed substring is more simple to use:

myDate.toString().substring(0,4);

LINQ with groupby and count

userInfos.GroupBy(userInfo => userInfo.metric)
        .OrderBy(group => group.Key)
        .Select(group => Tuple.Create(group.Key, group.Count()));

Insert multiple values using INSERT INTO (SQL Server 2005)

The syntax you are using is new to SQL Server 2008:

INSERT INTO [MyDB].[dbo].[MyTable]
       ([FieldID]
       ,[Description])
 VALUES
       (1000,N'test'),(1001,N'test2')

For SQL Server 2005, you will have to use multiple INSERT statements:

INSERT INTO [MyDB].[dbo].[MyTable]
       ([FieldID]
       ,[Description])
 VALUES
       (1000,N'test')

INSERT INTO [MyDB].[dbo].[MyTable]
       ([FieldID]
       ,[Description])
 VALUES
       (1001,N'test2')

One other option is to use UNION ALL:

INSERT INTO [MyDB].[dbo].[MyTable]
       ([FieldID]
       ,[Description])
SELECT 1000, N'test' UNION ALL
SELECT 1001, N'test2'

Error inflating class android.support.design.widget.NavigationView

One thing to double-check is that you have applied your theme correctly in your AndroidManifest.xml file. In my case, I had omitted the android:theme attribute. E.g:

<application ... android:theme="@style/Your.Theme.Here" ... >

Left/Right float button inside div

You can use justify-content: space-between in .test like so:

_x000D_
_x000D_
.test {_x000D_
  display: flex;_x000D_
  justify-content: space-between;_x000D_
  width: 20rem;_x000D_
  border: .1rem red solid;_x000D_
}
_x000D_
<div class="test">_x000D_
  <button>test</button>_x000D_
  <button>test</button>_x000D_
</div>
_x000D_
_x000D_
_x000D_


For those who want to use Bootstrap 4 can use justify-content-between:

_x000D_
_x000D_
div {_x000D_
  width: 20rem;_x000D_
  border: .1rem red solid;_x000D_
}
_x000D_
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css" rel="stylesheet" />_x000D_
<div class="d-flex justify-content-between">_x000D_
  <button>test</button>_x000D_
  <button>test</button>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to find the operating system version using JavaScript?

Hey for a quick solution you can consider the following library : UAPARSER - https://www.npmjs.com/package/ua-parser-js

example :

<script type="text/javascript" src="ua-parser.min.js"></script>
<script type="text/javascript">

var parser = new UAParser();
console.log(parser.getOS()) // will log  {name: "", version:""}

you can also install the library via npm, and import it like this:

import { UAParser } from 'ua-parser-js';
let parser = new UAParser();
parser.getOS();

the library is a JS based user agent string parser (window.navigator.userAgent is the user agent on browser) , so you can get with it other details aswell such as Browser,device,engines etc..and it can work with node js as well.

if you need typing for the library : https://www.npmjs.com/package/@types/ua-parser-js

CodeIgniter - How to return Json response from controller

For CodeIgniter 4, you can use the built-in API Response Trait

Here's sample code for reference:

<?php namespace App\Controllers;

use CodeIgniter\API\ResponseTrait;

class Home extends BaseController
{
    use ResponseTrait;

    public function index()
    {
        $data = [
            'data' => 'value1',
            'data2' => 'value2',
        ];

        return $this->respond($data);
    }
}

What's the difference between window.location= and window.location.replace()?

TLDR;

use location.href or better use window.location.href;

However if you read this you will gain undeniable proof.

The truth is it's fine to use but why do things that are questionable. You should take the higher road and just do it the way that it probably should be done.

location = "#/mypath/otherside"
var sections = location.split('/')

This code is perfectly correct syntax-wise, logic wise, type-wise you know the only thing wrong with it?

it has location instead of location.href

what about this

var mystring = location = "#/some/spa/route"

what is the value of mystring? does anyone really know without doing some test. No one knows what exactly will happen here. Hell I just wrote this and I don't even know what it does. location is an object but I am assigning a string will it pass the string or pass the location object. Lets say there is some answer to how this should be implemented. Can you guarantee all browsers will do the same thing?

This i can pretty much guess all browsers will handle the same.

var mystring = location.href = "#/some/spa/route"

What about if you place this into typescript will it break because the type compiler will say this is suppose to be an object?

This conversation is so much deeper than just the location object however. What this conversion is about what kind of programmer you want to be?

If you take this short-cut, yea it might be okay today, ye it might be okay tomorrow, hell it might be okay forever, but you sir are now a bad programmer. It won't be okay for you and it will fail you.

There will be more objects. There will be new syntax.

You might define a getter that takes only a string but returns an object and the worst part is you will think you are doing something correct, you might think you are brilliant for this clever method because people here have shamefully led you astray.

var Person.name = {first:"John":last:"Doe"}
console.log(Person.name) // "John Doe"

With getters and setters this code would actually work, but just because it can be done doesn't mean it's 'WISE' to do so.

Most people who are programming love to program and love to get better. Over the last few years I have gotten quite good and learn a lot. The most important thing I know now especially when you write Libraries is consistency and predictability.

Do the things that you can consistently do.

+"2" <-- this right here parses the string to a number. should you use it? or should you use parseInt("2")?

what about var num =+"2"?

From what you have learn, from the minds of stackoverflow i am not too hopefully.

If you start following these 2 words consistent and predictable. You will know the right answer to a ton of questions on stackoverflow.

Let me show you how this pays off. Normally I place ; on every line of javascript i write. I know it's more expressive. I know it's more clear. I have followed my rules. One day i decided not to. Why? Because so many people are telling me that it is not needed anymore and JavaScript can do without it. So what i decided to do this. Now because I have become sure of my self as a programmer (as you should enjoy the fruit of mastering a language) i wrote something very simple and i didn't check it. I erased one comma and I didn't think I needed to re-test for such a simple thing as removing one comma.

I wrote something similar to this in es6 and babel

var a = "hello world"
(async function(){
  //do work
})()

This code fail and took forever to figure out. For some reason what it saw was

var a = "hello world"(async function(){})()

hidden deep within the source code it was telling me "hello world" is not a function.

For more fun node doesn't show the source maps of transpiled code.

Wasted so much stupid time. I was presenting to someone as well about how ES6 is brilliant and then I had to start debugging and demonstrate how headache free and better ES6 is. Not convincing is it.

I hope this answered your question. This being an old question it's more for the future generation, people who are still learning.

Question when people say it doesn't matter either way works. Chances are a wiser more experienced person will tell you other wise.

what if someone overwrite the location object. They will do a shim for older browsers. It will get some new feature that needs to be shimmed and your 3 year old code will fail.

My last note to ponder upon.

Writing clean, clear purposeful code does something for your code that can't be answer with right or wrong. What it does is it make your code an enabler.

You can use more things plugins, Libraries with out fear of interruption between the codes.

for the record. use

window.location.href

What does ==$0 (double equals dollar zero) mean in Chrome Developer Tools?

$0 returns the most recently selected element or JavaScript object, $1 returns the second most recently selected one, and so on.

Refer : Command Line API Reference

How do I best silence a warning about unused variables?

First off the warning is generated by the variable definition in the source file not the header file. The header can stay pristine and should, since you might be using something like doxygen to generate the API-documentation.

I will assume that you have completely different implementation in source files. In these cases you can either comment out the offending parameter or just write the parameter.

Example:

func(int a, int b)
{
    b;
    foo(a);
}

This might seem cryptic, so defined a macro like UNUSED. The way MFC did it is:

#ifdef _DEBUG
#define UNUSED(x)
#else
#define UNUSED(x) x
#endif

Like this you see the warning still in debug builds, might be helpful.

use jQuery's find() on JSON object

Another option I wanted to mention, you could convert your data into XML and then use jQuery.find(":id='A'") the way you wanted.

There are jQuery plugins to that effect, like json2xml.

Probably not worth the conversion overhead, but that's a one time cost for static data, so it might be useful.

Media Player called in state 0, error (-38,0)

I am new in android programming and i had same error as this one. so i simply redefined the mp.createmediaPlayer = MediaPlayer.create(getApplicationContext(), Settings.System.DEFAULT_RINGTONE_URI). It may not the true way to do it but it worked fined for me:

try {
  mp = MediaPlayer.create(getApplicationContext(), Settings.System.DEFAULT_RINGTONE_URI);
} catch (Exception e) {
  e.printStackTrace();
}

mp.start();

Given an array of numbers, return array of products of all other numbers (no division)

To be complete here is the code in Scala:

val list1 = List(1, 2, 3, 4, 5)
for (elem <- list1) println(list1.filter(_ != elem) reduceLeft(_*_))

This will print out the following:

120
60
40
30
24

The program will filter out the current elem (_ != elem); and multiply the new list with reduceLeft method. I think this will be O(n) if you use scala view or Iterator for lazy eval.

What is the default scope of a method in Java?

The default scope is "default". It's weird--see these references for more info.

creating a random number using MYSQL

You could create a random number using FLOOR(RAND() * n) as randnum (n is an integer), however if you do not need the same random number to be repeated then you will have to somewhat store in a temp table. So you can check it against with where randnum not in (select * from temptable)...

How to add property to a class dynamically?

How to add property to a python class dynamically?

Say you have an object that you want to add a property to. Typically, I want to use properties when I need to begin managing access to an attribute in code that has downstream usage, so that I can maintain a consistent API. Now I will typically add them to the source code where the object is defined, but let's assume you don't have that access, or you need to truly dynamically choose your functions programmatically.

Create a class

Using an example based on the documentation for property, let's create a class of object with a "hidden" attribute and create an instance of it:

class C(object):
    '''basic class'''
    _x = None

o = C()

In Python, we expect there to be one obvious way of doing things. However, in this case, I'm going to show two ways: with decorator notation, and without. First, without decorator notation. This may be more useful for the dynamic assignment of getters, setters, or deleters.

Dynamic (a.k.a. Monkey Patching)

Let's create some for our class:

def getx(self):
    return self._x

def setx(self, value):
    self._x = value

def delx(self):
    del self._x

And now we assign these to the property. Note that we could choose our functions programmatically here, answering the dynamic question:

C.x = property(getx, setx, delx, "I'm the 'x' property.")

And usage:

>>> o.x = 'foo'
>>> o.x
'foo'
>>> del o.x
>>> print(o.x)
None
>>> help(C.x)
Help on property:

    I'm the 'x' property.

Decorators

We could do the same as we did above with decorator notation, but in this case, we must name the methods all the same name (and I'd recommend keeping it the same as the attribute), so programmatic assignment is not so trivial as it is using the above method:

@property
def x(self):
    '''I'm the 'x' property.'''
    return self._x

@x.setter
def x(self, value):
    self._x = value

@x.deleter
def x(self):
    del self._x

And assign the property object with its provisioned setters and deleters to the class:

C.x = x

And usage:

>>> help(C.x)
Help on property:

    I'm the 'x' property.

>>> o.x
>>> o.x = 'foo'
>>> o.x
'foo'
>>> del o.x
>>> print(o.x)
None

How to move a git repository into another directory and make that directory a git repository?

I am no expert, but I copy the .git folder to a new folder, then invoke: git reset --hard

Android: show soft keyboard automatically when focus is on an EditText

Why this answer - Because above solution will show your keyboard but it will not vanish if you click anywhere other that EditText. So you need to do something to make the keybaord disappear when EditText loses focus.

You can achieve this by doing the following steps:

  1. Make the parent view(content view of your activity) clickable and focusable by adding the following attributes

        android:clickable="true" 
        android:focusableInTouchMode="true" 
    
  2. Implement a hideKeyboard() method

        public void hideKeyboard(View view) {
            InputMethodManager inputMethodManager =(InputMethodManager)getSystemService(Activity.INPUT_METHOD_SERVICE);
            inputMethodManager.hideSoftInputFromWindow(view.getWindowToken(),InputMethodManager.HIDE_IMPLICIT_ONLY );
        }
    
  3. Lastly, set the onFocusChangeListener of your edittext.

        edittext.setOnFocusChangeListener(new View.OnFocusChangeListener() {
            @Override
            public void onFocusChange(View v, boolean hasFocus) {
                if (!hasFocus) {
                    hideKeyboard(v);
                }
            }
        });
    

.gitignore file for java eclipse project

put .gitignore in your main catalog

git status (you will see which files you can commit)
git add -A
git commit -m "message"
git push

How do you add Boost libraries in CMakeLists.txt?

Put this in your CMakeLists.txt file (change any options from OFF to ON if you want):

set(Boost_USE_STATIC_LIBS OFF) 
set(Boost_USE_MULTITHREADED ON)  
set(Boost_USE_STATIC_RUNTIME OFF) 
find_package(Boost 1.45.0 COMPONENTS *boost libraries here*) 

if(Boost_FOUND)
    include_directories(${Boost_INCLUDE_DIRS}) 
    add_executable(progname file1.cxx file2.cxx) 
    target_link_libraries(progname ${Boost_LIBRARIES})
endif()

Obviously you need to put the libraries you want where I put *boost libraries here*. For example, if you're using the filesystem and regex library you'd write:

find_package(Boost 1.45.0 COMPONENTS filesystem regex)

Allowed memory size of X bytes exhausted

This problem is happend because of php.ini defined limit was exided but have lot's of solution for this but simple one is to find your local servers folder and on that find the php folder and in that folder have php.ini file which have all declaration of these type setups. You just need to find one and change that value. But in this situation have one big problem once you change in your localhost file but what about server when you want to put your site on server it again produce same problem and you again follow the same for server. But you also know about .htaccess file this is one of the best and single place to do a lot's of things without changing core files. Like you change www routing, removing .php or other extentions from url or add one. Same like that you also difine default values of php.ini here like this - First you need to open the .htaccess file from your root directory or if you don't have this file so create one on root directory of your site and paste this code on it -

php_value upload_max_filesize 1000M
php_value post_max_size 99500M
php_value memory_limit 500M
php_value max_execution_time 300

after changes if you want to check the changes just run the php code

<?php phpinfo(); ?> 

it will show you the php cofigrations all details. So you find your changes.

Note: for defining unlimited just add -1 like php_value memory_limit -1 It's not good and most of the time slow down your server. But if you like to be limit less then this one option is also fit for you. If after refresh your page changes will not reflect you must restart your local server once for changes.

Good Luck. Hope it will help. Want to download the .htaccess file click this.

In excel how do I reference the current row but a specific column?

If you dont want to hard-code the cell addresses you can use the ROW() function.

eg: =AVERAGE(INDIRECT("A" & ROW()), INDIRECT("C" & ROW()))

Its probably not the best way to do it though! Using Auto-Fill and static columns like @JaiGovindani suggests would be much better.

"use database_name" command in PostgreSQL

Use this commad when first connect to psql

=# psql <databaseName> <usernamePostgresql>

Changes in import statement python3

Relative import happens whenever you are importing a package relative to the current script/package.

Consider the following tree for example:

mypkg
+-- base.py
+-- derived.py

Now, your derived.py requires something from base.py. In Python 2, you could do it like this (in derived.py):

from base import BaseThing

Python 3 no longer supports that since it's not explicit whether you want the 'relative' or 'absolute' base. In other words, if there was a Python package named base installed in the system, you'd get the wrong one.

Instead it requires you to use explicit imports which explicitly specify location of a module on a path-alike basis. Your derived.py would look like:

from .base import BaseThing

The leading . says 'import base from module directory'; in other words, .base maps to ./base.py.

Similarly, there is .. prefix which goes up the directory hierarchy like ../ (with ..mod mapping to ../mod.py), and then ... which goes two levels up (../../mod.py) and so on.

Please however note that the relative paths listed above were relative to directory where current module (derived.py) resides in, not the current working directory.


@BrenBarn has already explained the star import case. For completeness, I will have to say the same ;).

For example, you need to use a few math functions but you use them only in a single function. In Python 2 you were permitted to be semi-lazy:

def sin_degrees(x):
    from math import *
    return sin(degrees(x))

Note that it already triggers a warning in Python 2:

a.py:1: SyntaxWarning: import * only allowed at module level
  def sin_degrees(x):

In modern Python 2 code you should and in Python 3 you have to do either:

def sin_degrees(x):
    from math import sin, degrees
    return sin(degrees(x))

or:

from math import *

def sin_degrees(x):
    return sin(degrees(x))

How to minify php page html output?

This work for me.

function Minify_Html($Html)
{
   $Search = array(
    '/(\n|^)(\x20+|\t)/',
    '/(\n|^)\/\/(.*?)(\n|$)/',
    '/\n/',
    '/\<\!--.*?-->/',
    '/(\x20+|\t)/', # Delete multispace (Without \n)
    '/\>\s+\</', # strip whitespaces between tags
    '/(\"|\')\s+\>/', # strip whitespaces between quotation ("') and end tags
    '/=\s+(\"|\')/'); # strip whitespaces between = "'

   $Replace = array(
    "\n",
    "\n",
    " ",
    "",
    " ",
    "><",
    "$1>",
    "=$1");

$Html = preg_replace($Search,$Replace,$Html);
return $Html;
}

How to get current user who's accessing an ASP.NET application?

Using System.Web.HttpContext.Current.User.Identity.Name should work. Please check the IIS Site settings on the server that is hosting your site by doing the following:

  1. Go to IIS ? Sites ? Your Site ? Authentication

    IIS Settings

  2. Now check that Anonymous Access is Disabled & Windows Authentication is Enabled.

    Authentication

  3. Now System.Web.HttpContext.Current.User.Identity.Name should return something like this:

    domain\username

How to get all selected values from <select multiple=multiple>?

Unless a question asks for JQuery the question should be first answered in standard javascript as many people do not use JQuery in their sites.

From RobG How to get all selected values of a multiple select box using JavaScript?:

  function getSelectValues(select) {
  var result = [];
  var options = select && select.options;
  var opt;

  for (var i=0, iLen=options.length; i<iLen; i++) {
    opt = options[i];

    if (opt.selected) {
      result.push(opt.value || opt.text);
    }
  }
  return result;
}

How to get the ASCII value of a character

You are looking for:

ord()

WCF error: The caller was not authenticated by the service

If you use basicHttpBinding, configure the endpoint security to "None" and transport clientCredintialType to "None."

<bindings>
    <basicHttpBinding>
        <binding name="MyBasicHttpBinding">
            <security mode="None">
                <transport clientCredentialType="None" />
            </security>
        </binding>
    </basicHttpBinding>
</bindings>
<services>
    <service behaviorConfiguration="MyServiceBehavior" name="MyService">
        <endpoint 
            binding="basicHttpBinding" 
            bindingConfiguration="MyBasicHttpBinding"
            name="basicEndPoint"    
            contract="IMyService" 
        />
</service>

Also, make sure the directory Authentication Methods in IIS to Enable Anonymous access

How to get current SIM card number in Android?

Getting the Phone Number, IMEI, and SIM Card ID

TelephonyManager tm = (TelephonyManager) 
            getSystemService(Context.TELEPHONY_SERVICE);        

For SIM card, use the getSimSerialNumber()

    //---get the SIM card ID---
    String simID = tm.getSimSerialNumber();
    if (simID != null)
        Toast.makeText(this, "SIM card ID: " + simID, 
        Toast.LENGTH_LONG).show();

Phone number of your phone, use the getLine1Number() (some device's dont return the phone number)

    //---get the phone number---
    String telNumber = tm.getLine1Number();
    if (telNumber != null)        
        Toast.makeText(this, "Phone number: " + telNumber, 
        Toast.LENGTH_LONG).show();

IMEI number of the phone, use the getDeviceId()

    //---get the IMEI number---
    String IMEI = tm.getDeviceId();
    if (IMEI != null)        
        Toast.makeText(this, "IMEI number: " + IMEI, 
        Toast.LENGTH_LONG).show();

Permissions needed

<uses-permission android:name="android.permission.READ_PHONE_STATE"/>

ActiveMQ or RabbitMQ or ZeroMQ or

Edit: My initial answer had a strong focus on AMQP. I decided to rewrite it to offer a wider view on the topic.

These 3 messaging technologies have different approaches on building distributed systems :

RabbitMQ is one of the leading implementation of the AMQP protocol (along with Apache Qpid). Therefore, it implements a broker architecture, meaning that messages are queued on a central node before being sent to clients. This approach makes RabbitMQ very easy to use and deploy, because advanced scenarios like routing, load balancing or persistent message queuing are supported in just a few lines of code. However, it also makes it less scalable and “slower” because the central node adds latency and message envelopes are quite big.

ZeroMq is a very lightweight messaging system specially designed for high throughput/low latency scenarios like the one you can find in the financial world. Zmq supports many advanced messaging scenarios but contrary to RabbitMQ, you’ll have to implement most of them yourself by combining various pieces of the framework (e.g : sockets and devices). Zmq is very flexible but you’ll have to study the 80 pages or so of the guide (which I recommend reading for anybody writing distributed system, even if you don’t use Zmq) before being able to do anything more complicated than sending messages between 2 peers.

ActiveMQ is in the middle ground. Like Zmq, it can be deployed with both broker and P2P topologies. Like RabbitMQ, it’s easier to implement advanced scenarios but usually at the cost of raw performance. It’s the Swiss army knife of messaging :-).

Finally, all 3 products:

  • have client apis for the most common languages (C++, Java, .Net, Python, Php, Ruby, …)
  • have strong documentation
  • are actively supported

A better way to check if a path exists or not in PowerShell

If you just want an alternative to the cmdlet syntax, specifically for files, use the File.Exists() .NET method:

if(![System.IO.File]::Exists($path)){
    # file with path $path doesn't exist
}

If, on the other hand, you want a general purpose negated alias for Test-Path, here is how you should do it:

# Gather command meta data from the original Cmdlet (in this case, Test-Path)
$TestPathCmd = Get-Command Test-Path
$TestPathCmdMetaData = New-Object System.Management.Automation.CommandMetadata $TestPathCmd

# Use the static ProxyCommand.GetParamBlock method to copy 
# Test-Path's param block and CmdletBinding attribute
$Binding = [System.Management.Automation.ProxyCommand]::GetCmdletBindingAttribute($TestPathCmdMetaData)
$Params  = [System.Management.Automation.ProxyCommand]::GetParamBlock($TestPathCmdMetaData)

# Create wrapper for the command that proxies the parameters to Test-Path 
# using @PSBoundParameters, and negates any output with -not
$WrappedCommand = { 
    try { -not (Test-Path @PSBoundParameters) } catch { throw $_ }
}

# define your new function using the details above
$Function:notexists = '{0}param({1}) {2}' -f $Binding,$Params,$WrappedCommand

notexists will now behave exactly like Test-Path, but always return the opposite result:

PS C:\> Test-Path -Path "C:\Windows"
True
PS C:\> notexists -Path "C:\Windows"
False
PS C:\> notexists "C:\Windows" # positional parameter binding exactly like Test-Path
False

As you've already shown yourself, the opposite is quite easy, just alias exists to Test-Path:

PS C:\> New-Alias exists Test-Path
PS C:\> exists -Path "C:\Windows"
True

Concatenate columns in Apache Spark DataFrame

val newDf =
  df.withColumn(
    "NEW_COLUMN",
    concat(
      when(col("COL1").isNotNull, col("COL1")).otherwise(lit("null")),
      when(col("COL2").isNotNull, col("COL2")).otherwise(lit("null"))))

Note: For this code to work you need to put the parentheses "()" in the "isNotNull" function. -> The correct one is "isNotNull()".

val newDf =
  df.withColumn(
    "NEW_COLUMN",
    concat(
      when(col("COL1").isNotNull(), col("COL1")).otherwise(lit("null")),
      when(col("COL2").isNotNull(), col("COL2")).otherwise(lit("null"))))

Can't install APK from browser downloads

I had this problem. Couldn't install apk via the Downloads app. However opening the apk in a file manager app allowed me to install it fine. Using OI File Manager on stock Nexus 7 4.2.1

HTML colspan in CSS

There is no colspan in css as far as I know, but there will be column-span for multi column layout in the near future, but since it is only a draft in CSS3, you can check it in here. Anyway you can do a workaround using div and span with table-like display like this.

This would be the HTML:

<div class="table">
  <div class="row">
    <span class="cell red first"></span>
    <span class="cell blue fill"></span>
    <span class="cell green last"></span>
  </div>
</div>
<div class="table">
  <div class="row">
    <span class="cell black"></span>
  </div>
</div>

And this would be the css:

  /* this is to reproduce table-like structure
     for the sake of table-less layout. */
  .table { display:table; table-layout:fixed; width:100px; }
  .row { display:table-row; height:10px; }
  .cell { display:table-cell; }

  /* this is where the colspan tricks works. */
  span { width:100%; }

  /* below is for visual recognition test purposes only. */
  .red { background:red; }
  .blue { background:blue; }
  .green { background:green; }
  .black { background:black; }

  /* this is the benefit of using table display, it is able 
     to set the width of it's child object to fill the rest of 
     the parent width as in table */
  .first { width: 20px; }
  .last { width: 30px; }
  .fill { width: 100%; }

The only reason to use this trick is to gain the benefit of table-layout behaviour, I use it alot if only setting div and span width to certain percentage didn't fullfil our design requirement.

But if you don't need to benefit from the table-layout behaviour, then durilai's answer would suit you enough.

Use PHP to create, edit and delete crontab jobs?

Its simple You can you curl to do so, make sure curl installed on server :

for triggering every minute : * * * * * curl --request POST 'https://glassdoor.com/admin/sendBdayNotification'

        • *

    minute hour day month week

Let say you want to send this notification 2:15 PM everyday You may change POST/GET based on your API:

15 14 * * * curl --request POST 'url of ur API'

how to use json file in html code

<html>
<head>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js"> </script>

<script>

    $(function() {


   var people = [];

   $.getJSON('people.json', function(data) {
       $.each(data.person, function(i, f) {
          var tblRow = "<tr>" + "<td>" + f.firstName + "</td>" +
           "<td>" + f.lastName + "</td>" + "<td>" + f.job + "</td>" + "<td>" + f.roll + "</td>" + "</tr>"
           $(tblRow).appendTo("#userdata tbody");
     });

   });

});
</script>
</head>

<body>

<div class="wrapper">
<div class="profile">
   <table id= "userdata" border="2">
  <thead>
            <th>First Name</th>
            <th>Last Name</th>
            <th>Email Address</th>
            <th>City</th>
        </thead>
      <tbody>

       </tbody>
   </table>

</div>
</div>

</body>
</html>

My JSON file:

{
   "person": [
       {
           "firstName": "Clark",
           "lastName": "Kent",
           "job": "Reporter",
           "roll": 20
       },
       {
           "firstName": "Bruce",
           "lastName": "Wayne",
           "job": "Playboy",
           "roll": 30
       },
       {
           "firstName": "Peter",
           "lastName": "Parker",
           "job": "Photographer",
           "roll": 40
       }
   ]
}

I succeeded in integrating a JSON file to HTML table after working a day on it!!!

How to update-alternatives to Python 3 without breaking apt?

As I didn't want to break anything, I did this to be able to use newer versions of Python3 than Python v3.4 :

$ sudo update-alternatives --install /usr/local/bin/python3 python3 /usr/bin/python3.6 1
update-alternatives: using /usr/bin/python3.6 to provide /usr/local/bin/python3 (python3) in auto mode
$ sudo update-alternatives --install /usr/local/bin/python3 python3 /usr/bin/python3.7 2
update-alternatives: using /usr/bin/python3.7 to provide /usr/local/bin/python3 (python3) in auto mode
$ update-alternatives --list python3
/usr/bin/python3.6
/usr/bin/python3.7
$ sudo update-alternatives --config python3
There are 2 choices for the alternative python3 (providing /usr/local/bin/python3).

  Selection    Path                Priority   Status
------------------------------------------------------------
* 0            /usr/bin/python3.7   2         auto mode
  1            /usr/bin/python3.6   1         manual mode
  2            /usr/bin/python3.7   2         manual mode

Press enter to keep the current choice[*], or type selection number: 1
update-alternatives: using /usr/bin/python3.6 to provide /usr/local/bin/python3 (python3) in manual mode
$ ls -l /usr/local/bin/python3 /etc/alternatives/python3 
lrwxrwxrwx 1 root root 18 2019-05-03 02:59:03 /etc/alternatives/python3 -> /usr/bin/python3.6*
lrwxrwxrwx 1 root root 25 2019-05-03 02:58:53 /usr/local/bin/python3 -> /etc/alternatives/python3*

Running PHP script from the command line

UPDATE:

After misunderstanding, I finally got what you are trying to do. You should check your server configuration files; are you using apache2 or some other server software?

Look for lines that start with LoadModule php... There probably are configuration files/directories named mods or something like that, start from there.

You could also check output from php -r 'phpinfo();' | grep php and compare lines to phpinfo(); from web server.

To run php interactively:

(so you can paste/write code in the console)

php -a

To make it parse file and output to console:

php -f file.php

Parse file and output to another file:

php -f file.php > results.html

Do you need something else?

To run only small part, one line or like, you can use:

php -r '$x = "Hello World"; echo "$x\n";'

If you are running linux then do man php at console.

if you need/want to run php through fpm, use cli fcgi

SCRIPT_NAME="file.php" SCRIP_FILENAME="file.php" REQUEST_METHOD="GET" cgi-fcgi -bind -connect "/var/run/php-fpm/php-fpm.sock"

where /var/run/php-fpm/php-fpm.sock is your php-fpm socket file.

NULL value for int in Update statement

Assuming the column is set to support NULL as a value:

UPDATE YOUR_TABLE
   SET column = NULL

Be aware of the database NULL handling - by default in SQL Server, NULL is an INT. So if the column is a different data type you need to CAST/CONVERT NULL to the proper data type:

UPDATE YOUR_TABLE
   SET column = CAST(NULL AS DATETIME)

...assuming column is a DATETIME data type in the example above.

How to find out which processes are using swap space in Linux?

iotop is a very useful tool. It gives live stats of I/O and swap usage per process/thread. By default it shows per thread but you can do iotop -P to get per process info. This is not available by default. You may have to install via rpm/apt.

How do I write JSON data to a file?

All previous answers are correct here is a very simple example:

#! /usr/bin/env python
import json

def write_json():
    # create a dictionary  
    student_data = {"students":[]}
    #create a list
    data_holder = student_data["students"]
    # just a counter
    counter = 0
    #loop through if you have multiple items..         
    while counter < 3:
        data_holder.append({'id':counter})
        data_holder.append({'room':counter})
        counter += 1    
    #write the file        
    file_path='/tmp/student_data.json'
    with open(file_path, 'w') as outfile:
        print("writing file to: ",file_path)
        # HERE IS WHERE THE MAGIC HAPPENS 
        json.dump(student_data, outfile)
    outfile.close()     
    print("done")

write_json()

enter image description here

Laravel PHP Command Not Found

1) First, download the Laravel installer using Composer:

composer global require "laravel/installer"

2) Make sure to place the ~/.composer/vendor/bin directory in your PATH so the laravel executable can be located by your system.

  set PATH=%PATH%;%USERPROFILE%\AppData\Roaming\Composer\vendor\bin

  eg: “C:\Users\\AppData\Roaming\Composer\vendor\bin” 

3) Once installed, the simple laravel new command will create a fresh Laravel installation in the directory you specify.

eG:  laravel new blog

How do I sleep for a millisecond in Perl?

system "sleep 0.1";

does the trick.

Change the Right Margin of a View Programmatically?

EDIT: A more generic way of doing this that doesn't rely on the layout type (other than that it is a layout type which supports margins):

public static void setMargins (View v, int l, int t, int r, int b) {
    if (v.getLayoutParams() instanceof ViewGroup.MarginLayoutParams) {
        ViewGroup.MarginLayoutParams p = (ViewGroup.MarginLayoutParams) v.getLayoutParams();
        p.setMargins(l, t, r, b);
        v.requestLayout();
    }
}

You should check the docs for TextView. Basically, you'll want to get the TextView's LayoutParams object, and modify the margins, then set it back to the TextView. Assuming it's in a LinearLayout, try something like this:

TextView tv = (TextView)findViewById(R.id.my_text_view);
LinearLayout.LayoutParams params = (LinearLayout.LayoutParams)tv.getLayoutParams();
params.setMargins(0, 0, 10, 0); //substitute parameters for left, top, right, bottom
tv.setLayoutParams(params);

I can't test it right now, so my casting may be off by a bit, but the LayoutParams are what need to be modified to change the margin.

NOTE

Don't forget that if your TextView is inside, for example, a RelativeLayout, one should use RelativeLayout.LayoutParams instead of LinearLayout.LayoutParams

Data binding for TextBox

We can use following code

textBox1.DataBindings.Add("Text", model, "Name", false, DataSourceUpdateMode.OnPropertyChanged);

Where

  • "Text" – the property of textbox
  • model – the model object enter code here
  • "Name" – the value of model which to bind the textbox.

Center an element in Bootstrap 4 Navbar

I had a similar problem; the anchor text in my Bootstrap4 navbar wasn't centered. Simply added text-center in the anchor's class.

How to convert a ruby hash object to JSON?

require 'json/ext' # to use the C based extension instead of json/pure

puts {hash: 123}.to_json

Return HTML from ASP.NET Web API

Starting with AspNetCore 2.0, it's recommended to use ContentResult instead of the Produce attribute in this case. See: https://github.com/aspnet/Mvc/issues/6657#issuecomment-322586885

This doesn't rely on serialization nor on content negotiation.

[HttpGet]
public ContentResult Index() {
    return new ContentResult {
        ContentType = "text/html",
        StatusCode = (int)HttpStatusCode.OK,
        Content = "<html><body>Hello World</body></html>"
    };
}

Apache - MySQL Service detected with wrong path. / Ports already in use

Ok so i found out the problem :)

ctrl+alt+delete to start task manager, once you get to task manager go to services. find MySQL and right click on it. Then click stop process. That worked for me and i hope it works for you :D

md-table - How to update the column width

Right now, it has not been exposed at API level yet. However you can achieve it using something similar to this

<ng-container cdkColumnDef="userId" >
  <md-header-cell *cdkHeaderCellDef [ngClass]="'customWidthClass'"> ID </md-header-cell>
  <md-cell *cdkCellDef="let row" [ngClass]="'customWidthClass'"> {{row.id}} </md-cell>
</ng-container>

In css, you need to add this custom class -

.customWidthClass{
   flex: 0 0 75px;
}

Feel free to enter the logic to append class or custom width in here. It will apply custom width for the column.

Since md-table uses flex, we need to give fixed width in flex manner. This simply explains -

0 = don't grow (shorthand for flex-grow)

0 = don't shrink (shorthand for flex-shrink)

75px = start at 75px (shorthand for flex-basis)

Plunkr here - https://plnkr.co/edit/v7ww6DhJ6zCaPyQhPRE8?p=preview

Multiple values in single-value context

No, but that is a good thing since you should always handle your errors.

There are techniques that you can employ to defer error handling, see Errors are values by Rob Pike.

ew := &errWriter{w: fd}
ew.write(p0[a:b])
ew.write(p1[c:d])
ew.write(p2[e:f])
// and so on
if ew.err != nil {
    return ew.err
}

In this example from the blog post he illustrates how you could create an errWriter type that defers error handling till you are done calling write.

laravel collection to array

Try collect function in array like:

$comments_collection = collect($post->comments()->get()->toArray());

this methods can help you

toArray() with collect()

Checking if a key exists in a JavaScript object?

Checking for undefined-ness is not an accurate way of testing whether a key exists. What if the key exists but the value is actually undefined?

var obj = { key: undefined };
obj["key"] !== undefined // false, but the key exists!

You should instead use the in operator:

"key" in obj // true, regardless of the actual value

If you want to check if a key doesn't exist, remember to use parenthesis:

!("key" in obj) // true if "key" doesn't exist in object
!"key" in obj   // Do not do this! It is equivalent to "false in obj"

Or, if you want to particularly test for properties of the object instance (and not inherited properties), use hasOwnProperty:

obj.hasOwnProperty("key") // true

For performance comparison between the methods that are in, hasOwnProperty and key is undefined, see this benchmark

Inline instantiation of a constant List

You'll need to use a static readonly list instead. And if you want the list to be immutable then you might want to consider using ReadOnlyCollection<T> rather than List<T>.

private static readonly ReadOnlyCollection<string> _metrics =
    new ReadOnlyCollection<string>(new[]
        {
            SourceFile.LOC,
            SourceFile.MCCABE,
            SourceFile.NOM,
            SourceFile.NOA,
            SourceFile.FANOUT,
            SourceFile.FANIN,
            SourceFile.NOPAR,
            SourceFile.NDC,
            SourceFile.CALLS
        });

public static ReadOnlyCollection<string> Metrics
{
    get { return _metrics; }
}

Difference between VARCHAR2(10 CHAR) and NVARCHAR2(10)

The NVARCHAR2 datatype was introduced by Oracle for databases that want to use Unicode for some columns while keeping another character set for the rest of the database (which uses VARCHAR2). The NVARCHAR2 is a Unicode-only datatype.

One reason you may want to use NVARCHAR2 might be that your DB uses a non-Unicode character set and you still want to be able to store Unicode data for some columns without changing the primary character set. Another reason might be that you want to use two Unicode character set (AL32UTF8 for data that comes mostly from western Europe, AL16UTF16 for data that comes mostly from Asia for example) because different character sets won't store the same data equally efficiently.

Both columns in your example (Unicode VARCHAR2(10 CHAR) and NVARCHAR2(10)) would be able to store the same data, however the byte storage will be different. Some strings may be stored more efficiently in one or the other.

Note also that some features won't work with NVARCHAR2, see this SO question:

SVN 405 Method Not Allowed

I had a similar problem. I ended up nuking it from orbit, and lost my SVN history in the process. But at least I made that damn error go away.

This is probably a sub-optimal sequence of commands to execute, but it should fairly closely follow the sequence of commands that I actually did to get things to work:

cp -rp target ~/other/location/target-20111108
svn rm target --force
cp -rp ~/other/location/target-20111108 target-other-name
cd target-other-name
find . -name .svn -print | xargs rm -rf
cd ..
svn add target-other-name
svn ci -m "Re-re-re-re-re-re-re-re-re-re import target"
svn mv target-other-name target
svn ci -m "Re-re-re-re-re-re-re-re-re-re import target"

An unhandled exception of type 'System.TypeInitializationException' occurred in EntityFramework.dll

Check that right version is referenced in your project. E.g. the dll it is complaining about, could be from an older version and that's why there could be a version mismatch.

scroll up and down a div on button click using jquery

Just to add to other comments - it would be worth while to disable scrolling up whilst at the top of the page. If the user accidentally scrolls up whilst already at the top they would have to scroll down twice to start

if(scrolled != 0){
  $("#upClick").on("click" ,function(){
     scrolled=scrolled-300;
        $(".cover").animate({
          scrollTop:  scrolled
     });
  });
}

How to execute an .SQL script file using c#

This works for me:

public void updatedatabase()
{

    SqlConnection conn = new SqlConnection("Data Source=" + txtserver.Text.Trim() + ";Initial Catalog=" + txtdatabase.Text.Trim() + ";User ID=" + txtuserid.Text.Trim() + ";Password=" + txtpwd.Text.Trim() + "");
    try
    {

        conn.Open();

        string script = File.ReadAllText(Server.MapPath("~/Script/DatingDemo.sql"));

        // split script on GO command
        IEnumerable<string> commandStrings = Regex.Split(script, @"^\s*GO\s*$", RegexOptions.Multiline | RegexOptions.IgnoreCase);
        foreach (string commandString in commandStrings)
        {
            if (commandString.Trim() != "")
            {
                new SqlCommand(commandString, conn).ExecuteNonQuery();
            }
        }
        lblmsg.Text = "Database updated successfully.";

    }
    catch (SqlException er)
    {
        lblmsg.Text = er.Message;
        lblmsg.ForeColor = Color.Red;
    }
    finally
    {
        conn.Close();
    }
}

How to detect input type=file "change" for the same file?

If you don't want to use jQuery

<form enctype='multipart/form-data'>
    <input onchange="alert(this.value); return false;" type='file'>
    <br>
    <input type='submit' value='Upload'>
</form>

It works fine in Firefox, but for Chrome you need to add this.value=null; after alert.

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
            }

How can I make a time delay in Python?

Delays are done with the time library, specifically the time.sleep() function.

To just make it wait for a second:

from time import sleep
sleep(1)

This works because by doing:

from time import sleep

You extract the sleep function only from the time library, which means you can just call it with:

sleep(seconds)

Rather than having to type out

time.sleep()

Which is awkwardly long to type.

With this method, you wouldn't get access to the other features of the time library and you can't have a variable called sleep. But you could create a variable called time.

Doing from [library] import [function] (, [function2]) is great if you just want certain parts of a module.

You could equally do it as:

import time
time.sleep(1)

and you would have access to the other features of the time library like time.clock() as long as you type time.[function](), but you couldn't create the variable time because it would overwrite the import. A solution to this to do

import time as t

which would allow you to reference the time library as t, allowing you to do:

t.sleep()

This works on any library.

Should you use .htm or .html file extension? What is the difference, and which file is correct?

I guess it's a little too late now however the only time it does make a difference is when you set up HTML signatures on MS Outlook (even 2010). It's just not able to handle .html extensions, only .htm

Access Control Request Headers, is added to header in AJAX request with jQuery

Try to use the rack-cors gem. And add the header field in your Ajax call.

Word wrapping in phpstorm

WebStorm 10.0.4

For wrapping text/code line by deafault, but for all types of file: File -> Settings -> Editor -> General -> section "Soft Wraps" -> checkbox "Use soft wraps in editor"

(imho)

Tkinter understanding mainloop

while 1:
    root.update()

... is (very!) roughly similar to:

root.mainloop()

The difference is, mainloop is the correct way to code and the infinite loop is subtly incorrect. I suspect, though, that the vast majority of the time, either will work. It's just that mainloop is a much cleaner solution. After all, calling mainloop is essentially this under the covers:

while the_window_has_not_been_destroyed():
    wait_until_the_event_queue_is_not_empty()
    event = event_queue.pop()
    event.handle()

... which, as you can see, isn't much different than your own while loop. So, why create your own infinite loop when tkinter already has one you can use?

Put in the simplest terms possible: always call mainloop as the last logical line of code in your program. That's how Tkinter was designed to be used.

Can I get Unix's pthread.h to compile in Windows?

pthread.h isn't on Windows. But Windows has extensive threading functionality, beginning with CreateThread.

My advice is don't get caught looking at WinAPI through the lens of another system's API. These systems are different. It's like insisting on riding the Win32 bike with your comfortable Linux bike seat. Well, the seat might not fit right and in some cases it'll just fall off.

Threads pretty much work the same on different systems, you have ThreadPools and mutexes. Having worked with both pthreads and Windows threads, I can say the Windows threading offers quite a bit more functionality than pthread does.

Learning another API is pretty easy, just think in terms of the concepts (mutex, etc), then look up how to create one of those on MSDN.

Easy way to pull latest of all git submodules

Edit:

In the comments was pointed out (by philfreo ) that the latest version is required. If there is any nested submodules that need to be in their latest version :

git submodule foreach --recursive git pull

-----Outdated comment below-----

Isn't this the official way to do it ?

git submodule update --init

I use it every time. No problems so far.

Edit:

I just found that you can use:

git submodule foreach --recursive git submodule update --init 

Which will also recursively pull all of the submodules, i.e. dependancies.

What is the difference between BIT and TINYINT in MySQL?

A TINYINT is an 8-bit integer value, a BIT field can store between 1 bit, BIT(1), and 64 bits, BIT(64). For a boolean values, BIT(1) is pretty common.

Set initially selected item in Select list in Angular2

You can achieve the same using

<select [ngModel]="object">
  <option *ngFor="let object of objects;let i= index;" [value]="object.value" selected="i==0">{{object.name}}</option>
</select>

How do you convert a JavaScript date to UTC?

Convert to ISO without changing date/time

var now = new Date(); // Fri Feb 20 2015 19:29:31 GMT+0530 (India Standard Time) 
var isoDate = new Date(now.getTime() - now.getTimezoneOffset() * 60000).toISOString();
//OUTPUT : 2015-02-20T19:29:31.238Z

Convert to ISO with change in date/time(date/time will be changed)

isoDate = new Date(now).toISOString();
//OUTPUT : 2015-02-20T13:59:31.238Z 

Fiddle link

WCF, Service attribute value in the ServiceHost directive could not be found

You should configure your bin folder path to service local bin.

Syntax for a for loop in ruby

limit = array.length;
for counter in 0..limit
 --- make some actions ---
end

the other way to do that is the following

3.times do |n|
  puts n;
end

thats will print 0, 1, 2, so could be used like array iterator also

Think that variant better fit to the author's needs

Writing unit tests in Python: How do I start?

As others already replied, it's late to write unit tests, but not too late. The question is whether your code is testable or not. Indeed, it's not easy to put existing code under test, there is even a book about this: Working Effectively with Legacy Code (see key points or precursor PDF).

Now writing the unit tests or not is your call. You just need to be aware that it could be a tedious task. You might tackle this to learn unit-testing or consider writing acceptance (end-to-end) tests first, and start writing unit tests when you'll change the code or add new feature to the project.

TypeError: unhashable type: 'dict'

You're trying to use a dict as a key to another dict or in a set. That does not work because the keys have to be hashable. As a general rule, only immutable objects (strings, integers, floats, frozensets, tuples of immutables) are hashable (though exceptions are possible). So this does not work:

>>> dict_key = {"a": "b"}
>>> some_dict[dict_key] = True
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unhashable type: 'dict'

To use a dict as a key you need to turn it into something that may be hashed first. If the dict you wish to use as key consists of only immutable values, you can create a hashable representation of it like this:

>>> key = frozenset(dict_key.items())

Now you may use key as a key in a dict or set:

>>> some_dict[key] = True
>>> some_dict
{frozenset([('a', 'b')]): True}

Of course you need to repeat the exercise whenever you want to look up something using a dict:

>>> some_dict[dict_key]                     # Doesn't work
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unhashable type: 'dict'
>>> some_dict[frozenset(dict_key.items())]  # Works
True

If the dict you wish to use as key has values that are themselves dicts and/or lists, you need to recursively "freeze" the prospective key. Here's a starting point:

def freeze(d):
    if isinstance(d, dict):
        return frozenset((key, freeze(value)) for key, value in d.items())
    elif isinstance(d, list):
        return tuple(freeze(value) for value in d)
    return d

Expected response code 250 but got code "535", with message "535-5.7.8 Username and Password not accepted

I researched on the internet and some answers includes enabling the "access for lesser app" and "unlocking gmail captcha" which sadly didn't work for me until I found the 2-step verification.

What I did the following was:

  1. enable the 2-step verification to google HERE

  2. Create App Password to be use by your system HERE

  3. I selected Others (custom name) and clicked generate

  4. Went to my env file in laravel and edited this

    [email protected]

    MAIL_PASSWORD=thepasswordgenerated

  5. Restarted my apache server and boom! It works again.

This was my solution. I created this to atleast make other people not go wasting their time researching for a possible answer.

installation app blocked by play protect

There are three options to get rid of this warning:

  1. You need to disable Play Protect in Play Store -> Play Protect -> Settings Icon -> Scan Device for security threats
  2. Publish app at Google Play Store
  3. Submit an Appeal to the Play Protect.

How to request Google to re-crawl my website?

There are two options. The first (and better) one is using the Fetch as Google option in Webmaster Tools that Mike Flynn commented about. Here are detailed instructions:

  1. Go to: https://www.google.com/webmasters/tools/ and log in
  2. If you haven't already, add and verify the site with the "Add a Site" button
  3. Click on the site name for the one you want to manage
  4. Click Crawl -> Fetch as Google
  5. Optional: if you want to do a specific page only, type in the URL
  6. Click Fetch
  7. Click Submit to Index
  8. Select either "URL" or "URL and its direct links"
  9. Click OK and you're done.

With the option above, as long as every page can be reached from some link on the initial page or a page that it links to, Google should recrawl the whole thing. If you want to explicitly tell it a list of pages to crawl on the domain, you can follow the directions to submit a sitemap.

Your second (and generally slower) option is, as seanbreeden pointed out, submitting here: http://www.google.com/addurl/

Update 2019:

  1. Login to - Google Search Console
  2. Add a site and verify it with the available methods.
  3. After verification from the console, click on URL Inspection.
  4. In the Search bar on top, enter your website URL or custom URLs for inspection and enter.
  5. After Inspection, it'll show an option to Request Indexing
  6. Click on it and GoogleBot will add your website in a Queue for crawling.

What are these attributes: `aria-labelledby` and `aria-hidden`

ARIA does not change functionality, it only changes the presented roles/properties to screen reader users. WebAIM’s WAVE toolbar identifies ARIA roles on the page.

Recursive Lock (Mutex) vs Non-Recursive Lock (Mutex)

The difference between a recursive and non-recursive mutex has to do with ownership. In the case of a recursive mutex, the kernel has to keep track of the thread who actually obtained the mutex the first time around so that it can detect the difference between recursion vs. a different thread that should block instead. As another answer pointed out, there is a question of the additional overhead of this both in terms of memory to store this context and also the cycles required for maintaining it.

However, there are other considerations at play here too.

Because the recursive mutex has a sense of ownership, the thread that grabs the mutex must be the same thread that releases the mutex. In the case of non-recursive mutexes, there is no sense of ownership and any thread can usually release the mutex no matter which thread originally took the mutex. In many cases, this type of "mutex" is really more of a semaphore action, where you are not necessarily using the mutex as an exclusion device but use it as synchronization or signaling device between two or more threads.

Another property that comes with a sense of ownership in a mutex is the ability to support priority inheritance. Because the kernel can track the thread owning the mutex and also the identity of all the blocker(s), in a priority threaded system it becomes possible to escalate the priority of the thread that currently owns the mutex to the priority of the highest priority thread that is currently blocking on the mutex. This inheritance prevents the problem of priority inversion that can occur in such cases. (Note that not all systems support priority inheritance on such mutexes, but it is another feature that becomes possible via the notion of ownership).

If you refer to classic VxWorks RTOS kernel, they define three mechanisms:

  • mutex - supports recursion, and optionally priority inheritance. This mechanism is commonly used to protect critical sections of data in a coherent manner.
  • binary semaphore - no recursion, no inheritance, simple exclusion, taker and giver does not have to be same thread, broadcast release available. This mechanism can be used to protect critical sections, but is also particularly useful for coherent signalling or synchronization between threads.
  • counting semaphore - no recursion or inheritance, acts as a coherent resource counter from any desired initial count, threads only block where net count against the resource is zero.

Again, this varies somewhat by platform - especially what they call these things, but this should be representative of the concepts and various mechanisms at play.