Programs & Examples On #Ofx

Open Financial Exchange (OFX) is a unified specification for the electronic exchange of financial data between financial institutions, businesses and consumers via the Internet.

Customize Bootstrap checkboxes

You have to use Bootstrap version 4 with the custom-* classes to get this style:

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<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous">_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
_x000D_
<!-- example code of the bootstrap website -->_x000D_
<label class="custom-control custom-checkbox">_x000D_
  <input type="checkbox" class="custom-control-input">_x000D_
  <span class="custom-control-indicator"></span>_x000D_
  <span class="custom-control-description">Check this custom checkbox</span>_x000D_
</label>_x000D_
_x000D_
<!-- your code with the custom classes of version 4 -->_x000D_
<div class="checkbox">_x000D_
  <label class="custom-control custom-checkbox">_x000D_
    <input type="checkbox" [(ngModel)]="rememberMe" name="rememberme" class="custom-control-input">_x000D_
    <span class="custom-control-indicator"></span>_x000D_
    <span class="custom-control-description">Remember me</span>_x000D_
  </label>_x000D_
</div>
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Documentation: https://getbootstrap.com/docs/4.0/components/forms/#checkboxes-and-radios-1


Custom checkbox style on Bootstrap version 3?
Bootstrap version 3 doesn't have custom checkbox styles, but you can use your own. In this case: How to style a checkbox using CSS?

These custom styles are only available since version 4.

jQuery xml error ' No 'Access-Control-Allow-Origin' header is present on the requested resource.'

You won't be able to make an ajax call to http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml from a file deployed at http://run.jsbin.com due to the same-origin policy.


As the source (aka origin) page and the target URL are at different domains (run.jsbin.com and www.ecb.europa.eu), your code is actually attempting to make a Cross-domain (CORS) request, not an ordinary GET.

In a few words, the same-origin policy says that browsers should only allow ajax calls to services at the same domain of the HTML page.


Example:

A page at http://www.example.com/myPage.html can only directly request services that are at http://www.example.com, like http://www.example.com/api/myService. If the service is hosted at another domain (say http://www.ok.com/api/myService), the browser won't make the call directly (as you'd expect). Instead, it will try to make a CORS request.

To put it shortly, to perform a (CORS) request* across different domains, your browser:

  • Will include an Origin header in the original request (with the page's domain as value) and perform it as usual; and then
  • Only if the server response to that request contains the adequate headers (Access-Control-Allow-Origin is one of them) allowing the CORS request, the browse will complete the call (almost** exactly the way it would if the HTML page was at the same domain).
    • If the expected headers don't come, the browser simply gives up (like it did to you).


* The above depicts the steps in a simple request, such as a regular GET with no fancy headers. If the request is not simple (like a POST with application/json as content type), the browser will hold it a moment, and, before fulfilling it, will first send an OPTIONS request to the target URL. Like above, it only will continue if the response to this OPTIONS request contains the CORS headers. This OPTIONS call is known as preflight request.
** I'm saying almost because there are other differences between regular calls and CORS calls. An important one is that some headers, even if present in the response, will not be picked up by the browser if they aren't included in the Access-Control-Expose-Headers header.


How to fix it?

Was it just a typo? Sometimes the JavaScript code has just a typo in the target domain. Have you checked? If the page is at www.example.com it will only make regular calls to www.example.com! Other URLs, such as api.example.com or even example.com or www.example.com:8080 are considered different domains by the browser! Yes, if the port is different, then it is a different domain!

Add the headers. The simplest way to enable CORS is by adding the necessary headers (as Access-Control-Allow-Origin) to the server's responses. (Each server/language has a way to do that - check some solutions here.)

Last resort: If you don't have server-side access to the service, you can also mirror it (through tools such as reverse proxies), and include all the necessary headers there.

Shorter syntax for casting from a List<X> to a List<Y>?

dynamic data = List<x> val;  
List<y> val2 = ((IEnumerable)data).Cast<y>().ToList();

How to parse XML in Bash?

This is really just an explaination of Yuzem's answer, but I didn't feel like this much editing should be done to someone else, and comments don't allow formatting, so...

rdom () { local IFS=\> ; read -d \< E C ;}

Let's call that "read_dom" instead of "rdom", space it out a bit and use longer variables:

read_dom () {
    local IFS=\>
    read -d \< ENTITY CONTENT
}

Okay so it defines a function called read_dom. The first line makes IFS (the input field separator) local to this function and changes it to >. That means that when you read data instead of automatically being split on space, tab or newlines it gets split on '>'. The next line says to read input from stdin, and instead of stopping at a newline, stop when you see a '<' character (the -d for deliminator flag). What is read is then split using the IFS and assigned to the variable ENTITY and CONTENT. So take the following:

<tag>value</tag>

The first call to read_dom get an empty string (since the '<' is the first character). That gets split by IFS into just '', since there isn't a '>' character. Read then assigns an empty string to both variables. The second call gets the string 'tag>value'. That gets split then by the IFS into the two fields 'tag' and 'value'. Read then assigns the variables like: ENTITY=tag and CONTENT=value. The third call gets the string '/tag>'. That gets split by the IFS into the two fields '/tag' and ''. Read then assigns the variables like: ENTITY=/tag and CONTENT=. The fourth call will return a non-zero status because we've reached the end of file.

Now his while loop cleaned up a bit to match the above:

while read_dom; do
    if [[ $ENTITY = "title" ]]; then
        echo $CONTENT
        exit
    fi
done < xhtmlfile.xhtml > titleOfXHTMLPage.txt

The first line just says, "while the read_dom functionreturns a zero status, do the following." The second line checks if the entity we've just seen is "title". The next line echos the content of the tag. The four line exits. If it wasn't the title entity then the loop repeats on the sixth line. We redirect "xhtmlfile.xhtml" into standard input (for the read_dom function) and redirect standard output to "titleOfXHTMLPage.txt" (the echo from earlier in the loop).

Now given the following (similar to what you get from listing a bucket on S3) for input.xml:

<ListBucketResult xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
  <Name>sth-items</Name>
  <IsTruncated>false</IsTruncated>
  <Contents>
    <Key>[email protected]</Key>
    <LastModified>2011-07-25T22:23:04.000Z</LastModified>
    <ETag>&quot;0032a28286680abee71aed5d059c6a09&quot;</ETag>
    <Size>1785</Size>
    <StorageClass>STANDARD</StorageClass>
  </Contents>
</ListBucketResult>

and the following loop:

while read_dom; do
    echo "$ENTITY => $CONTENT"
done < input.xml

You should get:

 => 
ListBucketResult xmlns="http://s3.amazonaws.com/doc/2006-03-01/" => 
Name => sth-items
/Name => 
IsTruncated => false
/IsTruncated => 
Contents => 
Key => [email protected]
/Key => 
LastModified => 2011-07-25T22:23:04.000Z
/LastModified => 
ETag => &quot;0032a28286680abee71aed5d059c6a09&quot;
/ETag => 
Size => 1785
/Size => 
StorageClass => STANDARD
/StorageClass => 
/Contents => 

So if we wrote a while loop like Yuzem's:

while read_dom; do
    if [[ $ENTITY = "Key" ]] ; then
        echo $CONTENT
    fi
done < input.xml

We'd get a listing of all the files in the S3 bucket.

EDIT If for some reason local IFS=\> doesn't work for you and you set it globally, you should reset it at the end of the function like:

read_dom () {
    ORIGINAL_IFS=$IFS
    IFS=\>
    read -d \< ENTITY CONTENT
    IFS=$ORIGINAL_IFS
}

Otherwise, any line splitting you do later in the script will be messed up.

EDIT 2 To split out attribute name/value pairs you can augment the read_dom() like so:

read_dom () {
    local IFS=\>
    read -d \< ENTITY CONTENT
    local ret=$?
    TAG_NAME=${ENTITY%% *}
    ATTRIBUTES=${ENTITY#* }
    return $ret
}

Then write your function to parse and get the data you want like this:

parse_dom () {
    if [[ $TAG_NAME = "foo" ]] ; then
        eval local $ATTRIBUTES
        echo "foo size is: $size"
    elif [[ $TAG_NAME = "bar" ]] ; then
        eval local $ATTRIBUTES
        echo "bar type is: $type"
    fi
}

Then while you read_dom call parse_dom:

while read_dom; do
    parse_dom
done

Then given the following example markup:

<example>
  <bar size="bar_size" type="metal">bars content</bar>
  <foo size="1789" type="unknown">foos content</foo>
</example>

You should get this output:

$ cat example.xml | ./bash_xml.sh 
bar type is: metal
foo size is: 1789

EDIT 3 another user said they were having problems with it in FreeBSD and suggested saving the exit status from read and returning it at the end of read_dom like:

read_dom () {
    local IFS=\>
    read -d \< ENTITY CONTENT
    local RET=$?
    TAG_NAME=${ENTITY%% *}
    ATTRIBUTES=${ENTITY#* }
    return $RET
}

I don't see any reason why that shouldn't work

How to get current CPU and RAM usage in Python?

Only for Linux: One-liner for the RAM usage with only stdlib dependency:

import os
tot_m, used_m, free_m = map(int, os.popen('free -t -m').readlines()[-1].split()[1:])

edit: specified solution OS dependency

Is there an embeddable Webkit component for Windows / C# development?

There's a WebKit-Sharp component on Mono's GitHub Repository. I can't find any web-viewable documentation on it, and I'm not even sure if it's WinForms or GTK# (can't grab the source from here to check at the moment), but it's probably your best bet, either way.

How do I 'foreach' through a two-dimensional array?

string[][] languages = new string[2][];
            languages[0] = new string[2];
            languages[1] = new string[3];
// inserting data into double dimensional arrays.
            for (int i = 0; i < 2; i++)
            {
                languages[0][i] = "Jagged"+i.ToString();
            }
            for (int j = 0; j < 3; j++)
            {
                languages[1][j] = "Jag"+j.ToString();
            }

// doing foreach through 2 dimensional arrays.
foreach (string[] s in languages)
            {
                foreach (string a in s)
                {
                    Console.WriteLine(a);
                }
            }

Could not create work tree dir 'example.com'.: Permission denied

You should logged in not as "root" user.

Or assign permission to your "current_user" to do this by using following command

sudo chown -R username.www-data /var/www

sudo chmod -R +rwx /var/www

Correct way to write loops for promise.

Here's another method (ES6 w/std Promise). Uses lodash/underscore type exit criteria (return === false). Note that you could easily add an exitIf() method in options to run in doOne().

const whilePromise = (fnReturningPromise,options = {}) => { 
    // loop until fnReturningPromise() === false
    // options.delay - setTimeout ms (set to 0 for 1 tick to make non-blocking)
    return new Promise((resolve,reject) => {
        const doOne = () => {
            fnReturningPromise()
            .then((...args) => {
                if (args.length && args[0] === false) {
                    resolve(...args);
                } else {
                    iterate();
                }
            })
        };
        const iterate = () => {
            if (options.delay !== undefined) {
                setTimeout(doOne,options.delay);
            } else {
                doOne();
            }
        }
        Promise.resolve()
        .then(iterate)
        .catch(reject)
    })
};

Remove multiple objects with rm()

An other solution rm(list=ls(pattern="temp")), remove all objects matching the pattern.

Java Regex Replace with Capturing Group

Java 9 offers a Matcher.replaceAll() that accepts a replacement function:

resultString = regexMatcher.replaceAll(
        m -> String.valueOf(Integer.parseInt(m.group()) * 3));

position: fixed doesn't work on iPad and iPhone

The simple way to fix this problem just types transform property for your element. and it will be fixed. Happy Coding :-)

.classname{
  position: fixed;
  transform: translate3d(0,0,0);
}

Also you can try his way as well this is also work fine.

.classname{
      position: -webkit-sticky;
    }

How to copy selected files from Android with adb pull

As to the short script, the following runs on my Linux host

#!/bin/bash
HOST_DIR=<pull-to>
DEVICE_DIR=/sdcard/<pull-from>
EXTENSION="\.jpg"

while read MYFILE ; do
    adb pull "$DEVICE_DIR/$MYFILE" "$HOST_DIR/$MYFILE"
done < $(adb shell ls -1 "$DEVICE_DIR" | grep "$EXTENSION")

"ls minus one" lets "ls" show one file per line, and the quotation marks allow spaces in the filename.

How to set different colors in HTML in one statement?

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.rainbow {_x000D_
  background-image: -webkit-gradient( linear, left top, right top, color-stop(0, #f22), color-stop(0.15, #f2f), color-stop(0.3, #22f), color-stop(0.45, #2ff), color-stop(0.6, #2f2),color-stop(0.75, #2f2), color-stop(0.9, #ff2), color-stop(1, #f22) );_x000D_
  background-image: gradient( linear, left top, right top, color-stop(0, #f22), color-stop(0.15, #f2f), color-stop(0.3, #22f), color-stop(0.45, #2ff), color-stop(0.6, #2f2),color-stop(0.75, #2f2), color-stop(0.9, #ff2), color-stop(1, #f22) );_x000D_
  color:transparent;_x000D_
  -webkit-background-clip: text;_x000D_
  background-clip: text;_x000D_
}
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<h2><span class="rainbow">Rainbows are colorful and scalable and lovely</span></h2>
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How to get full REST request body using Jersey?

Since you're transferring data in xml, you could also (un)marshal directly from/to pojos.

There's an example (and more info) in the jersey user guide, which I copy here:

POJO with JAXB annotations:

@XmlRootElement
public class Planet {
    public int id;
    public String name;
    public double radius;
}

Resource:

@Path("planet")
public class Resource {

    @GET
    @Produces(MediaType.APPLICATION_XML)
    public Planet getPlanet() {
        Planet p = new Planet();
        p.id = 1;
        p.name = "Earth";
        p.radius = 1.0;

        return p;
    }

    @POST
    @Consumes(MediaType.APPLICATION_XML)
    public void setPlanet(Planet p) {
        System.out.println("setPlanet " + p.name);
    }

}      

The xml that gets produced/consumed:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<planet>
    <id>1</id>
    <name>Earth</name>
    <radius>1.0</radius>
</planet>

SQL Inner join more than two tables

A possible solution:

SELECT Company.Company_Id,Company.Company_Name,
    Invoice_Details.Invoice_No, Product_Details.Price
  FROM Company inner join Invoice_Details
    ON Company.Company_Id=Invoice_Details.Company_Id
 INNER JOIN Product_Details
        ON Invoice_Details.Invoice_No= Product_Details.Invoice_No
 WHERE Price='60000';

-- tets changes

How to select specific columns in laravel eloquent

You can use get() as well as all()

ModelName::where('a', 1)->get(['column1','column2']);

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

They are not doing the same job: $emit dispatches an event upwards through the scope hierarchy, while $broadcast dispatches an event downwards to all child scopes.

Check if table exists

You can use the available meta data:

  DatabaseMetaData meta = con.getMetaData();
  ResultSet res = meta.getTables(null, null, "My_Table_Name", 
     new String[] {"TABLE"});
  while (res.next()) {
     System.out.println(
        "   "+res.getString("TABLE_CAT") 
       + ", "+res.getString("TABLE_SCHEM")
       + ", "+res.getString("TABLE_NAME")
       + ", "+res.getString("TABLE_TYPE")
       + ", "+res.getString("REMARKS")); 
  }

See here for more details. Note also the caveats in the JavaDoc.

Getting a UnhandledPromiseRejectionWarning when testing using mocha/chai

I faced this issue:

(node:1131004) UnhandledPromiseRejectionWarning: Unhandled promise rejection (re jection id: 1): TypeError: res.json is not a function (node:1131004) DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.j s process with a non-zero exit code.

It was my mistake, I was replacing res object in then(function(res), so changed res to result and now it is working.

Wrong

module.exports.update = function(req, res){
        return Services.User.update(req.body)
                .then(function(res){//issue was here, res overwrite
                    return res.json(res);
                }, function(error){
                    return res.json({error:error.message});
                }).catch(function () {
                   console.log("Promise Rejected");
              });

Correction

module.exports.update = function(req, res){
        return Services.User.update(req.body)
                .then(function(result){//res replaced with result
                    return res.json(result);
                }, function(error){
                    return res.json({error:error.message});
                }).catch(function () {
                   console.log("Promise Rejected");
              });

Service code:

function update(data){
   var id = new require('mongodb').ObjectID(data._id);
        userData = {
                    name:data.name,
                    email:data.email,
                    phone: data.phone
                };
 return collection.findAndModify(
          {_id:id}, // query
          [['_id','asc']],  // sort order
          {$set: userData}, // replacement
          { "new": true }
          ).then(function(doc) {
                if(!doc)
                    throw new Error('Record not updated.');
                return doc.value;   
          });
    }

module.exports = {
        update:update
}

How to format a duration in java? (e.g format H:MM:SS)

In Scala, building up on YourBestBet's solution but simplified:

def prettyDuration(seconds: Long): List[String] = seconds match {
  case t if t < 60      => List(s"${t} seconds")
  case t if t < 3600    => s"${t / 60} minutes" :: prettyDuration(t % 60)
  case t if t < 3600*24 => s"${t / 3600} hours" :: prettyDuration(t % 3600)
  case t                => s"${t / (3600*24)} days" :: prettyDuration(t % (3600*24))
}

val dur = prettyDuration(12345).mkString(", ") // => 3 hours, 25 minutes, 45 seconds

Unable to read repository at http://download.eclipse.org/releases/indigo

I had the same problem. Try to deactivate your Firewall (I had avast!), which worked for me.

(Sorry for my English I'm French :D)

How to convert the background to transparent?

Paint.net is a free photo-editing tool that allows for transparent backgrounds. There is a simple example on YouTube http://www.youtube.com/watch?v=cdFpS-AvNCE. If you are still on Windows XP SP2 and that's an issue, I would first recommend doing the free service pack upgrade. But if that is not an option there are older versions of Paint.net that you could download and try.

Truncate (not round) decimal places in SQL Server

SELECT CAST(Value as Decimal(10,2)) FROM TABLE_NAME;

Would give you 2 values after the decimal point. (MS SQL SERVER)

How to actually search all files in Visual Studio

One can access the "Find in Files" window via the drop-down menu selection and search all files in the Entire Solution: Edit > Find and Replace > Find in Files

enter image description here

Other, alternative is to open the "Find in Files" window via the "Standard Toolbars" button as highlighted in the below screen-short:

enter image description here

Get only part of an Array in Java?

public static int[] range(int[] array, int start, int end){
        int returner[] = new int[end-start];
        for(int x = 0; x <= end-start-1; x++){
            returner[x] = array[x+start];
        }
        return returner;
    }

this is a way to do the same thing as Array.copyOfRange but without importing anything

How to execute python file in linux

1.save your file name as hey.py with the below given hello world script

#! /usr/bin/python
print('Hello, world!')

2.open the terminal in that directory

$ python hey.py

or if you are using python3 then

$ python3 hey.py

Adding one day to a date

Simplest solution:

$date = new DateTime('+1 day');
echo $date->format('Y-m-d H:i:s');

best practice to generate random token for forgot password

The earlier version of the accepted answer (md5(uniqid(mt_rand(), true))) is insecure and only offers about 2^60 possible outputs -- well within the range of a brute force search in about a week's time for a low-budget attacker:

Since a 56-bit DES key can be brute-forced in about 24 hours, and an average case would have about 59 bits of entropy, we can calculate 2^59 / 2^56 = about 8 days. Depending on how this token verification is implemented, it might be possible to practically leak timing information and infer the first N bytes of a valid reset token.

Since the question is about "best practices" and opens with...

I want to generate identifier for forgot password

...we can infer that this token has implicit security requirements. And when you add security requirements to a random number generator, the best practice is to always use a cryptographically secure pseudorandom number generator (abbreviated CSPRNG).


Using a CSPRNG

In PHP 7, you can use bin2hex(random_bytes($n)) (where $n is an integer larger than 15).

In PHP 5, you can use random_compat to expose the same API.

Alternatively, bin2hex(mcrypt_create_iv($n, MCRYPT_DEV_URANDOM)) if you have ext/mcrypt installed. Another good one-liner is bin2hex(openssl_random_pseudo_bytes($n)).

Separating the Lookup from the Validator

Pulling from my previous work on secure "remember me" cookies in PHP, the only effective way to mitigate the aforementioned timing leak (typically introduced by the database query) is to separate the lookup from the validation.

If your table looks like this (MySQL)...

CREATE TABLE account_recovery (
    id INTEGER(11) UNSIGNED NOT NULL AUTO_INCREMENT 
    userid INTEGER(11) UNSIGNED NOT NULL,
    token CHAR(64),
    expires DATETIME,
    PRIMARY KEY(id)
);

... you need to add one more column, selector, like so:

CREATE TABLE account_recovery (
    id INTEGER(11) UNSIGNED NOT NULL AUTO_INCREMENT 
    userid INTEGER(11) UNSIGNED NOT NULL,
    selector CHAR(16),
    token CHAR(64),
    expires DATETIME,
    PRIMARY KEY(id),
    KEY(selector)
);

Use a CSPRNG When a password reset token is issued, send both values to the user, store the selector and a SHA-256 hash of the random token in the database. Use the selector to grab the hash and User ID, calculate the SHA-256 hash of the token the user provides with the one stored in the database using hash_equals().

Example Code

Generating a reset token in PHP 7 (or 5.6 with random_compat) with PDO:

$selector = bin2hex(random_bytes(8));
$token = random_bytes(32);

$urlToEmail = 'http://example.com/reset.php?'.http_build_query([
    'selector' => $selector,
    'validator' => bin2hex($token)
]);

$expires = new DateTime('NOW');
$expires->add(new DateInterval('PT01H')); // 1 hour

$stmt = $pdo->prepare("INSERT INTO account_recovery (userid, selector, token, expires) VALUES (:userid, :selector, :token, :expires);");
$stmt->execute([
    'userid' => $userId, // define this elsewhere!
    'selector' => $selector,
    'token' => hash('sha256', $token),
    'expires' => $expires->format('Y-m-d\TH:i:s')
]);

Verifying the user-provided reset token:

$stmt = $pdo->prepare("SELECT * FROM account_recovery WHERE selector = ? AND expires >= NOW()");
$stmt->execute([$selector]);
$results = $stmt->fetchAll(PDO::FETCH_ASSOC);
if (!empty($results)) {
    $calc = hash('sha256', hex2bin($validator));
    if (hash_equals($calc, $results[0]['token'])) {
        // The reset token is valid. Authenticate the user.
    }
    // Remove the token from the DB regardless of success or failure.
}

These code snippets are not complete solutions (I eschewed the input validation and framework integrations), but they should serve as an example of what to do.

Reading JSON from a file?

The json.load() method (without "s" in "load") can read a file directly:

import json

with open('strings.json') as f:
    d = json.load(f)
    print(d)

You were using the json.loads() method, which is used for string arguments only.

Edit: The new message is a totally different problem. In that case, there is some invalid json in that file. For that, I would recommend running the file through a json validator.

There are also solutions for fixing json like for example How do I automatically fix an invalid JSON string?.

how do I insert a column at a specific column index in pandas?

df.insert(loc, column_name, value)

This will work if there is no other column with the same name. If a column, with your provided name already exists in the dataframe, it will raise a ValueError.

You can pass an optional parameter allow_duplicates with True value to create a new column with already existing column name.

Here is an example:



    >>> df = pd.DataFrame({'b': [1, 2], 'c': [3,4]})
    >>> df
       b  c
    0  1  3
    1  2  4
    >>> df.insert(0, 'a', -1)
    >>> df
       a  b  c
    0 -1  1  3
    1 -1  2  4
    >>> df.insert(0, 'a', -2)
    Traceback (most recent call last):
      File "", line 1, in 
      File "C:\Python39\lib\site-packages\pandas\core\frame.py", line 3760, in insert
        self._mgr.insert(loc, column, value, allow_duplicates=allow_duplicates)
      File "C:\Python39\lib\site-packages\pandas\core\internals\managers.py", line 1191, in insert
        raise ValueError(f"cannot insert {item}, already exists")
    ValueError: cannot insert a, already exists
    >>> df.insert(0, 'a', -2,  allow_duplicates = True)
    >>> df
       a  a  b  c
    0 -2 -1  1  3
    1 -2 -1  2  4

Round number to nearest integer

int(round(x))

Will round it and change it to integer

EDIT:

You are not assigning int(round(h)) to any variable. When you call int(round(h)), it returns the integer number but does nothing else; you have to change that line for:

h = int(round(h))

To assign the new value to h

EDIT 2:

As @plowman said in the comments, Python's round() doesn't work as one would normally expect, and that's because the way the number is stored as a variable is usually not the way you see it on screen. There are lots of answers that explain this behavior:

round() doesn't seem to be rounding properly

One way to avoid this problem is to use the Decimal as stated by this answer: https://stackoverflow.com/a/15398691/4345659

In order for this answer to work properly without using extra libraries it would be convenient to use a custom rounding function. After a lot of corrections, I came up with the following solution, that as far as I tested avoided all the storing issues. It is based on using the string representation, obtained with repr() (NOT str()!). It looks hacky but it was the only way I found to solve all the cases. It works with both Python2 and Python3.

def proper_round(num, dec=0):
    num = str(num)[:str(num).index('.')+dec+2]
    if num[-1]>='5':
        return float(num[:-2-(not dec)]+str(int(num[-2-(not dec)])+1))
    return float(num[:-1])

Tests:

>>> print(proper_round(1.0005,3))
1.001
>>> print(proper_round(2.0005,3))
2.001
>>> print(proper_round(3.0005,3))
3.001
>>> print(proper_round(4.0005,3))
4.001
>>> print(proper_round(5.0005,3))
5.001
>>> print(proper_round(1.005,2))
1.01
>>> print(proper_round(2.005,2))
2.01
>>> print(proper_round(3.005,2))
3.01
>>> print(proper_round(4.005,2))
4.01
>>> print(proper_round(5.005,2))
5.01
>>> print(proper_round(1.05,1))
1.1
>>> print(proper_round(2.05,1))
2.1
>>> print(proper_round(3.05,1))
3.1
>>> print(proper_round(4.05,1))
4.1
>>> print(proper_round(5.05,1))
5.1
>>> print(proper_round(1.5))
2.0
>>> print(proper_round(2.5))
3.0
>>> print(proper_round(3.5))
4.0
>>> print(proper_round(4.5))
5.0
>>> print(proper_round(5.5))
6.0
>>> 
>>> print(proper_round(1.000499999999,3))
1.0
>>> print(proper_round(2.000499999999,3))
2.0
>>> print(proper_round(3.000499999999,3))
3.0
>>> print(proper_round(4.000499999999,3))
4.0
>>> print(proper_round(5.000499999999,3))
5.0
>>> print(proper_round(1.00499999999,2))
1.0
>>> print(proper_round(2.00499999999,2))
2.0
>>> print(proper_round(3.00499999999,2))
3.0
>>> print(proper_round(4.00499999999,2))
4.0
>>> print(proper_round(5.00499999999,2))
5.0
>>> print(proper_round(1.0499999999,1))
1.0
>>> print(proper_round(2.0499999999,1))
2.0
>>> print(proper_round(3.0499999999,1))
3.0
>>> print(proper_round(4.0499999999,1))
4.0
>>> print(proper_round(5.0499999999,1))
5.0
>>> print(proper_round(1.499999999))
1.0
>>> print(proper_round(2.499999999))
2.0
>>> print(proper_round(3.499999999))
3.0
>>> print(proper_round(4.499999999))
4.0
>>> print(proper_round(5.499999999))
5.0

Finally, the corrected answer would be:

# Having proper_round defined as previously stated
h = int(proper_round(h))

EDIT 3:

Tests:

>>> proper_round(6.39764125, 2)
6.31 # should be 6.4
>>> proper_round(6.9764125, 1)
6.1  # should be 7

The gotcha here is that the dec-th decimal can be 9 and if the dec+1-th digit >=5 the 9 will become a 0 and a 1 should be carried to the dec-1-th digit.

If we take this into consideration, we get:

def proper_round(num, dec=0):
    num = str(num)[:str(num).index('.')+dec+2]
    if num[-1]>='5':
      a = num[:-2-(not dec)]       # integer part
      b = int(num[-2-(not dec)])+1 # decimal part
      return float(a)+b**(-dec+1) if a and b == 10 else float(a+str(b))
    return float(num[:-1])

In the situation described above b = 10 and the previous version would just concatenate a and b which would result in a concatenation of 10 where the trailing 0 would disappear. This version transforms b to the right decimal place based on dec, as a proper carry.

How to work with progress indicator in flutter?

I took the following approach, which uses a simple modal progress indicator widget that wraps whatever you want to make modal during an async call.

The example in the package also addresses how to handle form validation while making async calls to validate the form (see flutter/issues/9688 for details of this problem). For example, without leaving the form, this async form validation method can be used to validate a new user name against existing names in a database while signing up.

https://pub.dartlang.org/packages/modal_progress_hud

Here is the demo of the example provided with the package (with source code):

async form validation with modal progress indicator

Example could be adapted to other modal progress indicator behaviour (like different animations, additional text in modal, etc..).

iOS 7: UITableView shows under status bar

Please note: This worked for me for the following configuration:

  • No navigation bar at the top of the screen (table view meets status bar)
  • Table view is non-scrollable

If the above two requirements aren't met your milage may vary.

Original Post

I created my view programmatically and this ended up working for me:

- (void) viewDidLayoutSubviews {
    // only works for iOS 7+
    if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0) {
        CGRect viewBounds = self.view.bounds;
        CGFloat topBarOffset = self.topLayoutGuide.length;

        // snaps the view under the status bar (iOS 6 style)
        viewBounds.origin.y = topBarOffset * -1;

        // shrink the bounds of your view to compensate for the offset
        viewBounds.size.height = viewBounds.size.height + (topBarOffset * -1);
        self.view.bounds = viewBounds;
    }
}

Source (in topLayoutGuide section at bottom of pg.39).

Proper use cases for Android UserManager.isUserAGoat()?

It's not an inside joke

Apparently it's just an application checker for Goat Simulator - by Coffee Stain Studios

If you have Goat Simulator installed, you're a goat. If you don't have it installed, you're not a goat.

I imagine it was more of a personal experiment by one of the developers, most likely to find people with a common interest.

Calling a function of a module by using its name (a string)

For what it's worth, if you needed to pass the function (or class) name and app name as a string, then you could do this:

myFnName  = "MyFn"
myAppName = "MyApp"
app = sys.modules[myAppName]
fn  = getattr(app,myFnName)

Speed up rsync with Simultaneous/Concurrent File Transfers?

The shortest version I found is to use the --cat option of parallel like below. This version avoids using xargs, only relying on features of parallel:

cat files.txt | \
  parallel -n 500 --lb --pipe --cat rsync --files-from={} user@remote:/dir /dir -avPi

#### Arg explainer
# -n 500           :: split input into chunks of 500 entries
#
# --cat            :: create a tmp file referenced by {} containing the 500 
#                     entry content for each process
#
# user@remote:/dir :: the root relative to which entries in files.txt are considered
#
# /dir             :: local root relative to which files are copied

Sample content from files.txt:

/dir/file-1
/dir/subdir/file-2
....

Note that this doesn't use -j 50 for job count, that didn't work on my end here. Instead I've used -n 500 for record count per job, calculated as a reasonable number given the total number of records.

Equivalent of varchar(max) in MySQL?

The max length of a varchar is

65535

divided by the max byte length of a character in the character set the column is set to (e.g. utf8=3 bytes, ucs2=2, latin1=1).

minus 2 bytes to store the length

minus the length of all the other columns

minus 1 byte for every 8 columns that are nullable. If your column is null/not null this gets stored as one bit in a byte/bytes called the null mask, 1 bit per column that is nullable.

Spring Security with roles and permissions

After reading this post, from Baeldung. I found that the solution is pretty simple.

What I have done, is to add the role and permissions into the GrantedAuthority. I was able to access both methods hasRole() and hasAuthority().

JQuery datepicker not working

You did not include the datepicker library

so add

<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jqueryui/1.8.11/jquery-ui.min.js"></script>

to your <head> tag

live demo

How to inspect FormData?

You have to understand that FormData::entries() returns an instance of Iterator.

Take this example form:

<form name="test" id="form-id">
    <label for="name">Name</label>
    <input name="name" id="name" type="text">
    <label for="pass">Password</label>
    <input name="pass" id="pass" type="text">
</form>

and this JS-loop:

<script>
    var it = new FormData( document.getElementById('form-id') ).entries();
    var current = {};
    while ( ! current.done ) {
        current = it.next();
        console.info( current )
    }
</script>

Is it possible to create a 'link to a folder' in a SharePoint document library?

The simplest way is to use the following pattern:

http://[server]/[site]/[ListName]/[Folder]/[SubFolder]

To place a shortcut to a document library:

  1. Upload it as *.url file. However, by default, this file type is not allowed.
  2. Go to you Document Library settings > Advanced Settings > Allow management of content types. Add the "Link to document" content type to a document library and paste the link

How do I center this form in css?

I css I got no idea but I made that just by centering the form in html something like this:

in css:

form.principal {width:12em;}    
form.principal label { float:left; display:block; clear:both; padding:3px;}
form.principal input { float:left; width:8em;}
form.principal button{clear:both; width:130px; height:50px; margin-top:8px;}

then in html:

<center><form class="principal" method="POST">
<fieldset>
<p><label for="username">User</label><input id="username" type="text" name="username" />
<p><label for="password">Password</label><input id="password" type="password" name="password" /></p>
<button>Log in</button>
</fieldset>
</form></center>

This will center the form, and the content will be in the left of the centered form.

Converting JSON to XML in Java

If you want to replace any node value you can do like this

JSONObject json = new JSONObject(str);
String xml = XML.toString(json);
xml.replace("old value", "new value");

Is there a way to make Firefox ignore invalid ssl-certificates?

I ran into this issue when trying to get to one of my companies intranet sites. Here is the solution I used:

  1. enter about:config into the firefox address bar and agree to continue.
  2. search for the preference named security.ssl.enable_ocsp_stapling.
  3. double-click this item to change its value to false.

This will lower your security as you will be able to view sites with invalid certs. Firefox will still prompt you that the cert is invalid and you have the choice to proceed forward, so it was worth the risk for me.

How to grep a text file which contains some binary data?

Here's what I used in a system that didn't have "strings" command installed

cat yourfilename | tr -cd "[:print:]"

This prints the text and removes unprintable characters in one fell swoop, unlike "cat -v filename" which requires some postprocessing to remove unwanted stuff. Note that some of the binary data may be printable so you'll still get some gibberish between the good stuff. I think strings removes this gibberish too if you can use that.

View tabular file such as CSV from command line

My FOSS project CSVfix allows you to display CSV files in "ASCII art" table format.

How can I select rows with most recent timestamp for each key value?

I had mostly the same problem and ended up a a different solution that makes this type of problem trivial to query.

I have a table of sensor data (1 minute data from about 30 sensors)

SensorReadings->(timestamp,value,idSensor)

and I have a sensor table that has lots of mostly static stuff about the sensor but the relevant fields are these:

Sensors->(idSensor,Description,tvLastUpdate,tvLastValue,...)

The tvLastupdate and tvLastValue are set in a trigger on inserts to the SensorReadings table. I always have direct access to these values without needing to do any expensive queries. This does denormalize slightly. The query is trivial:

SELECT idSensor,Description,tvLastUpdate,tvLastValue 
FROM Sensors

I use this method for data that is queried often. In my case I have a sensor table, and a large event table, that have data coming in at the minute level AND dozens of machines are updating dashboards and graphs with that data. With my data scenario the trigger-and-cache method works well.

HTML5 iFrame Seamless Attribute

Updated: October 2016

The seamless attribute no longer exists. It was originally pitched to be included in the first HTML5 spec, but subsequently dropped. An unrelated attribute of the same name made a brief cameo in the HTML5.1 draft, but that too was ditched mid-2016:

So I think the gist of it all both from the implementor side and the web-dev side is that seamless as-specced doesn’t seem to be what anybody wanted to begin with. Or at least it’s more than anybody actually wanted. And anyway like @annevk says, it’s seems a lot of it’s since been “overcome by events” in light of Shadow DOM.

In other words: purge the seamless attribute from your memory, and pretend it never existed.

For posterity's sake, here's my original answer from five years ago:

Original answer: April 2011

The attribute is in draft mode at the moment. For that reason, none of the current browsers are supporting it yet (as the implementation is subject to change). In the meantime, it's best just to use CSS to strip the borders/scrollbars from the iframe:

iframe[seamless]{
    background-color: transparent;
    border: 0px none transparent;
    padding: 0px;
    overflow: hidden;
}

There's more to the seamless attribute than what can be added with CSS: part of the reasoning behind the attribute was to allow nested content to inherit the same styles applied to the iframe (acting as though the embedded document was one big nested inside the element, for example).

Lastly, versions of Internet Explorer (8 and earlier) require additional attributes in order to remove the borders, scrollbars and background colour:

<iframe frameborder="0" allowtransparency="true" scrolling="no" src="..."></iframe>

Naturally, this doesn't validate. So it's up to you how to handle it. My (picky) approach would be to sniff the agent string and add the attributes for IE versions earlier than 9.

Hope that helps. :)

What does it mean to "call" a function in Python?

When you "call" a function you are basically just telling the program to execute that function. So if you had a function that added two numbers such as:

def add(a,b):
    return a + b

you would call the function like this:

add(3,5)

which would return 8. You can put any two numbers in the parentheses in this case. You can also call a function like this:

answer = add(4,7)

Which would set the variable answer equal to 11 in this case.

Python and SQLite: insert into table

Not a direct answer, but here is a function to insert a row with column-value pairs into sqlite table:

def sqlite_insert(conn, table, row):
    cols = ', '.join('"{}"'.format(col) for col in row.keys())
    vals = ', '.join(':{}'.format(col) for col in row.keys())
    sql = 'INSERT INTO "{0}" ({1}) VALUES ({2})'.format(table, cols, vals)
    conn.cursor().execute(sql, row)
    conn.commit()

Example of use:

sqlite_insert(conn, 'stocks', {
        'created_at': '2016-04-17',
        'type': 'BUY',
        'amount': 500,
        'price': 45.00})

Note, that table name and column names should be validated beforehand.

How to retrieve a file from a server via SFTP?

Though answers above were very helpful, I've spent a day to make them work, facing various exceptions like "broken channel", "rsa key unknown" and "packet corrupt".

Below is a working reusable class for SFTP FILES UPLOAD/DOWNLOAD using JSch library.

Upload usage:

SFTPFileCopy upload = new SFTPFileCopy(true, /path/to/sourcefile.png", /path/to/destinationfile.png");

Download usage:

SFTPFileCopy download = new SFTPFileCopy(false, "/path/to/sourcefile.png", "/path/to/destinationfile.png");

The class code:

import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import com.jcraft.jsch.UIKeyboardInteractive;
import com.jcraft.jsch.UserInfo;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import javax.swing.JOptionPane;
import menue.Menue;

public class SFTPFileCopy1 {

    public SFTPFileCopy1(boolean upload, String sourcePath, String destPath) throws FileNotFoundException, IOException {
        Session session = null;
        Channel channel = null;
        ChannelSftp sftpChannel = null;
        try {
            JSch jsch = new JSch();
            //jsch.setKnownHosts("/home/user/.putty/sshhostkeys");
            session = jsch.getSession("login", "mysite.com", 22);
            session.setPassword("password");

            UserInfo ui = new MyUserInfo() {
                public void showMessage(String message) {

                    JOptionPane.showMessageDialog(null, message);

                }

                public boolean promptYesNo(String message) {

                    Object[] options = {"yes", "no"};

                    int foo = JOptionPane.showOptionDialog(null,
                            message,
                            "Warning",
                            JOptionPane.DEFAULT_OPTION,
                            JOptionPane.WARNING_MESSAGE,
                            null, options, options[0]);

                    return foo == 0;

                }
            };
            session.setUserInfo(ui);

            session.setConfig("StrictHostKeyChecking", "no");
            session.connect();
            channel = session.openChannel("sftp");
            channel.setInputStream(System.in);
            channel.setOutputStream(System.out);
            channel.connect();
            sftpChannel = (ChannelSftp) channel;

            if (upload) { // File upload.
                byte[] bufr = new byte[(int) new File(sourcePath).length()];
                FileInputStream fis = new FileInputStream(new File(sourcePath));
                fis.read(bufr);
                ByteArrayInputStream fileStream = new ByteArrayInputStream(bufr);
                sftpChannel.put(fileStream, destPath);
                fileStream.close();
            } else { // File download.
                byte[] buffer = new byte[1024];
                BufferedInputStream bis = new BufferedInputStream(sftpChannel.get(sourcePath));
                OutputStream os = new FileOutputStream(new File(destPath));
                BufferedOutputStream bos = new BufferedOutputStream(os);
                int readCount;
                while ((readCount = bis.read(buffer)) > 0) {
                    bos.write(buffer, 0, readCount);
                }
                bis.close();
                bos.close();
            }
        } catch (Exception e) {
            System.out.println(e);
        } finally {
            if (sftpChannel != null) {
                sftpChannel.exit();
            }
            if (channel != null) {
                channel.disconnect();
            }
            if (session != null) {
                session.disconnect();
            }
        }
    }

    public static abstract class MyUserInfo
            implements UserInfo, UIKeyboardInteractive {

        public String getPassword() {
            return null;
        }

        public boolean promptYesNo(String str) {
            return false;
        }

        public String getPassphrase() {
            return null;
        }

        public boolean promptPassphrase(String message) {
            return false;
        }

        public boolean promptPassword(String message) {
            return false;
        }

        public void showMessage(String message) {
        }

        public String[] promptKeyboardInteractive(String destination,
                String name,
                String instruction,
                String[] prompt,
                boolean[] echo) {

            return null;
        }
    }
}

How to use __doPostBack()

Like others have said, you need to provide the UniqueID of the control to the __doPostback() method.

__doPostBack('<%= btn.UniqueID %>', '');

On the server, the submitted form values are identified by the name attribute of the fields in the page.

The reason why UniqueID works is because UniqueID and name are in fact the same thing when the server control is rendered in HTML.

Here's an article that describes what is the UniqueID:

The UniqueID property is also used to provide value for the HTML "name" attribute of input fields (checkboxes, dropdown lists, and hidden fields). UniqueID also plays major role in postbacks. The UniqueID property of a server control, which supports postbacks, provides data for the __EVENTTARGET hidden field. The ASP.NET Runtime then uses the __EVENTTARGET field to find the control which triggered the postback and then calls its RaisePostBackEvent method.

src: https://www.telerik.com/blogs/the-difference-between-id-clientid-and-uniqueid

jQuery Datepicker close datepicker after selected date

actually you don't need to replace this all....

there are 2 ways to do this. One is to use autoclose property, the other (alternativ) way is to use the on change property thats fired by the input when selecting a Date.

HTML

<div class="container">
    <div class="hero-unit">
        <input type="text" placeholder="Sample 1: Click to show datepicker" id="example1">
    </div>
    <div class="hero-unit">
        <input type="text" placeholder="Sample 2: Click to show datepicker" id="example2">
    </div>
</div>

jQuery

$(document).ready(function () {
    $('#example1').datepicker({
        format: "dd/mm/yyyy",
        autoclose: true
    });

    //Alternativ way
    $('#example2').datepicker({
      format: "dd/mm/yyyy"
    }).on('change', function(){
        $('.datepicker').hide();
    });

});

this is all you have to do :)

HERE IS A FIDDLE to see whats happening.

Fiddleupdate on 13 of July 2016: CDN wasnt present anymore

According to your EDIT:

$('#example1').datepicker().on('changeDate', function (ev) {
    $('#example1').Close();
});

Here you take the Input (that has no Close-Function) and create a Datepicker-Element. If the element changes you want to close it but you still try to close the Input (That has no close-function).

Binding a mouseup event to the document state may not be the best idea because you will fire all containing scripts on each click!

Thats it :)

EDIT: August 2017 (Added a StackOverFlowFiddle aka Snippet. Same as in Top of Post)

_x000D_
_x000D_
$(document).ready(function () {_x000D_
    $('#example1').datepicker({_x000D_
        format: "dd/mm/yyyy",_x000D_
        autoclose: true_x000D_
    });_x000D_
_x000D_
    //Alternativ way_x000D_
    $('#example2').datepicker({_x000D_
      format: "dd/mm/yyyy"_x000D_
    }).on('change', function(){_x000D_
        $('.datepicker').hide();_x000D_
    });_x000D_
});
_x000D_
.hero-unit{_x000D_
  float: left;_x000D_
  width: 210px;_x000D_
  margin-right: 25px;_x000D_
}_x000D_
.hero-unit input{_x000D_
  width: 100%;_x000D_
}
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jqueryui/1.12.1/jquery-ui.min.js"></script>_x000D_
<div class="container">_x000D_
    <div class="hero-unit">_x000D_
        <input type="text" placeholder="Sample 1: Click to show datepicker" id="example1">_x000D_
    </div>_x000D_
    <div class="hero-unit">_x000D_
        <input type="text" placeholder="Sample 2: Click to show datepicker" id="example2">_x000D_
    </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

EDIT: December 2018 Obviously Bootstrap-Datepicker doesnt work with jQuery 3.x see this to fix

Filtering by Multiple Specific Model Properties in AngularJS (in OR relationship)

Pretty straight forward approach using filterBy in angularJs

For working plnkr follow this link

http://plnkr.co/edit/US6xE4h0gD5CEYV0aMDf?p=preview

This has specially used a single property to search against multiple column but not all.

<!DOCTYPE html>
<html ng-app="myApp">

  <head>
    <script data-require="[email protected]" data-semver="1.4.1" src="https://code.angularjs.org/1.4.1/angular.js"></script>
    <script data-require="[email protected]" data-semver="0.5.2" src="https://cdnjs.cloudflare.com/ajax/libs/angular-filter/0.5.2/angular-filter.js"></script>
    <link rel="stylesheet" href="style.css" />
    <script src="script.js"></script>
  </head>

  <body ng-controller="myCtrl as vm">
  <input type="text" placeholder="enter your search text" ng-model="vm.searchText" />
   <table>
     <tr ng-repeat="row in vm.tableData | filterBy: ['col1','col2']: vm.searchText">
       <td>{{row.col1}}</td>
       <td>{{row.col2}}</td>
       <td>{{row.col3}}</td>
     </tr>
   </table>
   <p>This will show filter from <b>two columns</b> only(col1 and col2) . Not from all. Whatever columns you add into filter array they
   will be searched. all columns will be used by default if you use <b>filter: vm.searchText</b></p>
  </body>
</html>

controller

// Code goes here
(function(){

  var myApp = angular.module('myApp',['angular.filter']);

  myApp.controller('myCtrl', function($scope){
    var vm= this;
    vm.x = 20;

    vm.tableData = [
      {
        col1: 'Ashok',
        col2: 'Tewatia',
        col3: '12'
      },{
        col1: 'Babita',
        col2: 'Malik',
        col3: '34'
      },{
        col1: 'Dinesh',
        col2: 'Tewatia',
        col3: '56'
      },{
        col1: 'Sabita',
        col2: 'Malik',
        col3: '78'
      }
      ];
  })

})();

How can I check if an element exists in the visible DOM?

All existing elements have parentElement set, except the HTML element!

function elExists (e) { 
    return (e.nodeName === 'HTML' || e.parentElement !== null);
};

Check if an HTML input element is empty or has no value entered by user

You want:

if (document.getElementById('customx').value === ""){
    //do something
}

The value property will give you a string value and you need to compare that against an empty string.

Python Pandas User Warning: Sorting because non-concatenation axis is not aligned

tl;dr:

concat and append currently sort the non-concatenation index (e.g. columns if you're adding rows) if the columns don't match. In pandas 0.23 this started generating a warning; pass the parameter sort=True to silence it. In the future the default will change to not sort, so it's best to specify either sort=True or False now, or better yet ensure that your non-concatenation indices match.


The warning is new in pandas 0.23.0:

In a future version of pandas pandas.concat() and DataFrame.append() will no longer sort the non-concatenation axis when it is not already aligned. The current behavior is the same as the previous (sorting), but now a warning is issued when sort is not specified and the non-concatenation axis is not aligned, link.

More information from linked very old github issue, comment by smcinerney :

When concat'ing DataFrames, the column names get alphanumerically sorted if there are any differences between them. If they're identical across DataFrames, they don't get sorted.

This sort is undocumented and unwanted. Certainly the default behavior should be no-sort.

After some time the parameter sort was implemented in pandas.concat and DataFrame.append:

sort : boolean, default None

Sort non-concatenation axis if it is not already aligned when join is 'outer'. The current default of sorting is deprecated and will change to not-sorting in a future version of pandas.

Explicitly pass sort=True to silence the warning and sort. Explicitly pass sort=False to silence the warning and not sort.

This has no effect when join='inner', which already preserves the order of the non-concatenation axis.

So if both DataFrames have the same columns in the same order, there is no warning and no sorting:

df1 = pd.DataFrame({"a": [1, 2], "b": [0, 8]}, columns=['a', 'b'])
df2 = pd.DataFrame({"a": [4, 5], "b": [7, 3]}, columns=['a', 'b'])

print (pd.concat([df1, df2]))
   a  b
0  1  0
1  2  8
0  4  7
1  5  3

df1 = pd.DataFrame({"a": [1, 2], "b": [0, 8]}, columns=['b', 'a'])
df2 = pd.DataFrame({"a": [4, 5], "b": [7, 3]}, columns=['b', 'a'])

print (pd.concat([df1, df2]))
   b  a
0  0  1
1  8  2
0  7  4
1  3  5

But if the DataFrames have different columns, or the same columns in a different order, pandas returns a warning if no parameter sort is explicitly set (sort=None is the default value):

df1 = pd.DataFrame({"a": [1, 2], "b": [0, 8]}, columns=['b', 'a'])
df2 = pd.DataFrame({"a": [4, 5], "b": [7, 3]}, columns=['a', 'b'])

print (pd.concat([df1, df2]))

FutureWarning: Sorting because non-concatenation axis is not aligned.

   a  b
0  1  0
1  2  8
0  4  7
1  5  3

print (pd.concat([df1, df2], sort=True))
   a  b
0  1  0
1  2  8
0  4  7
1  5  3

print (pd.concat([df1, df2], sort=False))
   b  a
0  0  1
1  8  2
0  7  4
1  3  5

If the DataFrames have different columns, but the first columns are aligned - they will be correctly assigned to each other (columns a and b from df1 with a and b from df2 in the example below) because they exist in both. For other columns that exist in one but not both DataFrames, missing values are created.

Lastly, if you pass sort=True, columns are sorted alphanumerically. If sort=False and the second DafaFrame has columns that are not in the first, they are appended to the end with no sorting:

df1 = pd.DataFrame({"a": [1, 2], "b": [0, 8], 'e':[5, 0]}, 
                    columns=['b', 'a','e'])
df2 = pd.DataFrame({"a": [4, 5], "b": [7, 3], 'c':[2, 8], 'd':[7, 0]}, 
                    columns=['c','b','a','d'])

print (pd.concat([df1, df2]))

FutureWarning: Sorting because non-concatenation axis is not aligned.

   a  b    c    d    e
0  1  0  NaN  NaN  5.0
1  2  8  NaN  NaN  0.0
0  4  7  2.0  7.0  NaN
1  5  3  8.0  0.0  NaN

print (pd.concat([df1, df2], sort=True))
   a  b    c    d    e
0  1  0  NaN  NaN  5.0
1  2  8  NaN  NaN  0.0
0  4  7  2.0  7.0  NaN
1  5  3  8.0  0.0  NaN

print (pd.concat([df1, df2], sort=False))

   b  a    e    c    d
0  0  1  5.0  NaN  NaN
1  8  2  0.0  NaN  NaN
0  7  4  NaN  2.0  7.0
1  3  5  NaN  8.0  0.0

In your code:

placement_by_video_summary = placement_by_video_summary.drop(placement_by_video_summary_new.index)
                                                       .append(placement_by_video_summary_new, sort=True)
                                                       .sort_index()

To get total number of columns in a table in sql

In my situation, I was comparing table schema column count for 2 identical tables in 2 databases; one is the main database and the other is the archival database. I did this (SQL 2012+):

DECLARE @colCount1 INT;
DECLARE @colCount2 INT;

SELECT @colCount1 = COUNT(COLUMN_NAME) FROM MainDB.INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'SomeTable';
SELECT @colCount2 = COUNT(COLUMN_NAME) FROM ArchiveDB.INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'SomeTable';

IF (@colCount1 != @colCount2) THROW 5000, 'Number of columns in both tables are not equal. The archive schema may need to be updated.', 16;

The important thing to notice here is qualifying the database name before INFORMATION_SCHEMA (which is a schema, like dbo). This will allow the code to break, in case columns were added to the main database and not to the archival database, in which if the procedure were allowed to run, data loss would almost certainly occur.

How to check the function's return value if true or false

Wrong syntax. You can't compare a Boolean to a string like "false" or "true". In your case, just test it's inverse:

if(!ValidateForm()) { ...

You could test against the constant false, but it's rather ugly and generally frowned upon:

if(ValidateForm() == false) { ...

Multi-Line Comments in Ruby?

=begin comment line 1 comment line 2 =end make sure =begin and =end is the first thing on that line (no spaces)

How to add new activity to existing project in Android Studio?

To add an Activity using Android Studio.

This step is same as adding Fragment, Service, Widget, and etc. Screenshot provided.

[UPDATE] Android Studio 3.5. Note that I have removed the steps for the older version. I assume almost all is using version 3.x.

enter image description here

  1. Right click either java package/java folder/module, I recommend to select a java package then right click it so that the destination of the Activity will be saved there
  2. Select/Click New
  3. Select Activity
  4. Choose an Activity that you want to create, probably the basic one.

To add a Service, or a BroadcastReceiver, just do the same step.

cannot open shared object file: No such file or directory

Copied from my answer here: https://stackoverflow.com/a/9368199/485088

Run ldconfig as root to update the cache - if that still doesn't help, you need to add the path to the file ld.so.conf (just type it in on its own line) or better yet, add the entry to a new file (easier to delete) in directory ld.so.conf.d.

How can I do a line break (line continuation) in Python?

Put a \ at the end of your line or enclose the statement in parens ( .. ). From IBM:

b = ((i1 < 20) and
     (i2 < 30) and
     (i3 < 40))

or

b = (i1 < 20) and \
    (i2 < 30) and \
    (i3 < 40)

Send SMTP email using System.Net.Mail via Exchange Online (Office 365)

In year of 2020, these code seems to return exception as

System.Net.Mail.SmtpStatusCode.MustIssueStartTlsFirst or The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.57 SMTP; Client was not authenticated to send anonymous mail during MAIL FROM

This code is working for me.

            using (SmtpClient client = new SmtpClient()
            {
                Host = "smtp.office365.com",
                Port = 587,
                UseDefaultCredentials = false, // This require to be before setting Credentials property
                DeliveryMethod = SmtpDeliveryMethod.Network,
                Credentials = new NetworkCredential("[email protected]", "password"), // you must give a full email address for authentication 
                TargetName = "STARTTLS/smtp.office365.com", // Set to avoid MustIssueStartTlsFirst exception
                EnableSsl = true // Set to avoid secure connection exception
            })
            {

                MailMessage message = new MailMessage()
                {
                    From = new MailAddress("[email protected]"), // sender must be a full email address
                    Subject = subject,
                    IsBodyHtml = true,
                    Body = "<h1>Hello World</h1>",
                    BodyEncoding = System.Text.Encoding.UTF8,
                    SubjectEncoding = System.Text.Encoding.UTF8,

                };
                var toAddresses = recipients.Split(',');
                foreach (var to in toAddresses)
                {
                    message.To.Add(to.Trim());
                }

                try
                {
                    client.Send(message);
                }
                catch (Exception ex)
                {
                    Debug.WriteLine(ex.Message);
                }
            }

Create comma separated strings C#?

Another approach is to use the CommaDelimitedStringCollection class from System.Configuration namespace/assembly. It behaves like a list plus it has an overriden ToString method that returns a comma-separated string.

Pros - More flexible than an array.

Cons - You can't pass a string containing a comma.

CommaDelimitedStringCollection list = new CommaDelimitedStringCollection();

list.AddRange(new string[] { "Huey", "Dewey" });
list.Add("Louie");
//list.Add(",");

string s = list.ToString(); //Huey,Dewey,Louie

How to check currently internet connection is available or not in android

Use Below Code:

private boolean isNetworkAvailable() {
  ConnectivityManager connectivityManager 
      = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
  NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
  return activeNetworkInfo != null && activeNetworkInfo.isConnected();
}

if isNetworkAvailable() returns true then internet connection available, otherwise internet connection not available

Here need to add below uses-permission in your application Manifest file

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

How can I get customer details from an order in WooCommerce?

I just dealt with this. Depending on what you really want, you can get the details from the order like this:

$field = get_post_meta($order->id, $field_name, true);

Where $field_name is '_billing_address_1' or '_shipping_address_1'or 'first_name'. You can google the other fields, but don't forget the "" at the beginning.

If you want to retrieve the customer for this order, and get its field directly, it works as in your solution, except you do not need to retrieve the full customer object:

$customer_id = (int)$order->user_id;

$field = get_user_meta($customer_id, $field_name, true);

Now in this case, the $field_name does not start with "_". For example: 'first_name' and 'billing_address_1'.

OnItemClickListener using ArrayAdapter for ListView

Use OnItemClickListener

   ListView lv = getListView();
   lv.setOnItemClickListener(new OnItemClickListener()
   {
      @Override
      public void onItemClick(AdapterView<?> adapter, View v, int position,
            long arg3) 
      {
            String value = (String)adapter.getItemAtPosition(position); 
            // assuming string and if you want to get the value on click of list item
            // do what you intend to do on click of listview row
      }
   });

When you click on a row a listener is fired. So you setOnClickListener on the listview and use the annonymous inner class OnItemClickListener.

You also override onItemClick. The first param is a adapter. Second param is the view. third param is the position ( index of listview items).

Using the position you get the item .

Edit : From your comments i assume you need to set the adapter o listview

So assuming your activity extends ListActivtiy

     setListAdapter(adapter); 

Or if your activity class extends Activity

     ListView lv = (ListView) findViewById(R.id.listview1);
     //initialize adapter 
     lv.setAdapter(adapter); 

Best way to concatenate List of String objects?

Using the Functional Java library, import these:

import static fj.pre.Monoid.stringMonoid;
import static fj.data.List.list;
import fj.data.List;

... then you can do this:

List<String> ss = list("foo", "bar", "baz");
String s = stringMonoid.join(ss, ", ");

Or, the generic way, if you don't have a list of Strings:

public static <A> String showList(List<A> l, Show<A> s) {
  return stringMonoid.join(l.map(s.showS_()), ", ");
}

Mysql error 1452 - Cannot add or update a child row: a foreign key constraint fails

Make sure the value is in the other table otherwise you will get this error, in the assigned corresponding column.

So if it is assigned column is assigned to a row id of another table , make sure there is a row that is in the table otherwise this error will appear.

Display calendar to pick a date in java

  1. Open your Java source code document and navigate to the JTable object you have created inside of your Swing class.

  2. Create a new TableModel object that holds a DatePickerTable. You must create the DatePickerTable with a range of date values in MMDDYYYY format. The first value is the begin date and the last is the end date. In code, this looks like:

    TableModel datePicker = new DatePickerTable("01011999","12302000");
    
  3. Set the display interval in the datePicker object. By default each day is displayed, but you may set a regular interval. To set a 15-day interval between date options, use this code:

    datePicker.interval = 15;
    
  4. Attach your table model into your JTable:

    JTable newtable = new JTable (datePicker);
    

    Your Java application now has a drop-down date selection dialog.

What is the proper way to comment functions in Python?

I would go a step further than just saying "use a docstring". Pick a documentation generation tool, such as pydoc or epydoc (I use epydoc in pyparsing), and use the markup syntax recognized by that tool. Run that tool often while you are doing your development, to identify holes in your documentation. In fact, you might even benefit from writing the docstrings for the members of a class before implementing the class.

How do I check that multiple keys are in a dict in a single pass?

>>> if 'foo' in foo and 'bar' in foo:
...     print 'yes'
... 
yes

Jason, () aren't necessary in Python.

Adding item to Dictionary within loop

# Let's add key:value to a dictionary, the functional way 
# Create your dictionary class 
class my_dictionary(dict): 
    # __init__ function 
    def __init__(self): 
        self = dict()   
    # Function to add key:value 
    def add(self, key, value): 
        self[key] = value 
# Main Function 
dict_obj = my_dictionary() 
limit = int(input("Enter the no of key value pair in a dictionary"))
c=0
while c < limit :   
    dict_obj.key = input("Enter the key: ") 
    dict_obj.value = input("Enter the value: ") 
    dict_obj.add(dict_obj.key, dict_obj.value) 
    c += 1
print(dict_obj) 

Android TextView padding between lines

you can look into android:lineSpacingExtra and apply it to your XML

Additional Info is on this page

or the related method public void setLineSpacing (float add, float mult)

Additional Info here

.htaccess 301 redirect of single page

You could also use a RewriteRule if you wanted the ability to template match and redirect urls.

Cannot implicitly convert type 'System.Linq.IQueryable' to 'System.Collections.Generic.IList'

You can replace IList<DzieckoAndOpiekun> resultV with var resultV.

What is :: (double colon) in Python when subscripting sequences?

TL;DR

This visual example will show you how to a neatly select elements in a NumPy Matrix (2 dimensional array) in a pretty entertaining way (I promise). Step 2 below illustrate the usage of that "double colons" :: in question.

(Caution: this is a NumPy array specific example with the aim of illustrating the a use case of "double colons" :: for jumping of elements in multiple axes. This example does not cover native Python data structures like List).

One concrete example to rule them all...

Say we have a NumPy matrix that looks like this:

In [1]: import numpy as np

In [2]: X = np.arange(100).reshape(10,10)

In [3]: X
Out[3]:
array([[ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9],
       [10, 11, 12, 13, 14, 15, 16, 17, 18, 19],
       [20, 21, 22, 23, 24, 25, 26, 27, 28, 29],
       [30, 31, 32, 33, 34, 35, 36, 37, 38, 39],
       [40, 41, 42, 43, 44, 45, 46, 47, 48, 49],
       [50, 51, 52, 53, 54, 55, 56, 57, 58, 59],
       [60, 61, 62, 63, 64, 65, 66, 67, 68, 69],
       [70, 71, 72, 73, 74, 75, 76, 77, 78, 79],
       [80, 81, 82, 83, 84, 85, 86, 87, 88, 89],
       [90, 91, 92, 93, 94, 95, 96, 97, 98, 99]])

Say for some reason, your boss wants you to select the following elements:

enter image description here

"But How???"... Read on! (We can do this in a 2-step approach)

Step 1 - Obtain subset

Specify the "start index" and "end index" in both row-wise and column-wise directions.

enter image description here

In code:

In [5]: X2 = X[2:9,3:8]

In [6]: X2
Out[6]:
array([[23, 24, 25, 26, 27],
       [33, 34, 35, 36, 37],
       [43, 44, 45, 46, 47],
       [53, 54, 55, 56, 57],
       [63, 64, 65, 66, 67],
       [73, 74, 75, 76, 77],
       [83, 84, 85, 86, 87]])

Notice now we've just obtained our subset, with the use of simple start and end indexing technique. Next up, how to do that "jumping"... (read on!)

Step 2 - Select elements (with the "jump step" argument)

We can now specify the "jump steps" in both row-wise and column-wise directions (to select elements in a "jumping" way) like this:

enter image description here

In code (note the double colons):

In [7]: X3 = X2[::3, ::2]

In [8]: X3
Out[8]:
array([[23, 25, 27],
       [53, 55, 57],
       [83, 85, 87]])

We have just selected all the elements as required! :)

 Consolidate Step 1 (start and end) and Step 2 ("jumping")

Now we know the concept, we can easily combine step 1 and step 2 into one consolidated step - for compactness:

In [9]: X4 = X[2:9,3:8][::3,::2]

    In [10]: X4
    Out[10]:
    array([[23, 25, 27],
           [53, 55, 57],
           [83, 85, 87]])

Done!

PyCharm import external library

Answer for PyCharm 2016.1 on OSX: (This is an update to the answer by @GeorgeWilliams993's answer above, but I don't have the rep yet to make comments.)

Go to Pycharm menu --> Preferences --> Project: (projectname) --> Project Interpreter

At the top is a popup for "Project Interpreter," and to the right of it is a button with ellipses (...) - click on this button for a different popup and choose "More" (or, as it turns out, click on the main popup and choose "Show All").

This shows a list of interpreters, with one selected. At the bottom of the screen are a set of tools... pick the rightmost one:

Show path for the selected interpreter button

Now you should see all the paths pycharm is searching to find imports, and you can use the "+" button at the bottom to add a new path.

I think the most significant difference from @GeorgeWilliams993's answer is that the gear button has been replaced by a set of ellipses. That threw me off.

Escaping ampersand in URL

You can use the % character to 'escape' characters that aren't allowed in URLs. See [RFC 1738].

A table of ASCII values on http://www.asciitable.com/.

You can see & is 26 in hexadecimal - so you need M%26M.

How to add line breaks to an HTML textarea?

I have a textarea with id is #infoartist follow:

<textarea id="infoartist" ng-show="dForm" style="width: 100%;" placeholder="Tell your contacts and collectors about yourself."></textarea>

In javascript code, i'll get value of textarea and replace escaping new line (\n\r) by <br /> tag, such as:

var text = document.getElementById("infoartist").value;
text = text.replace(/\r?\n/g, '<br />');

So if you are using jquery (like me):

var text = $("#infoartist").val();
text = text.replace(/\r?\n/g, '<br />');

Hope it helped you. :-)

Running script upon login mac

tl;dr: use OSX's native process launcher and manager, launchd.

To do so, make a launchctl daemon. You'll have full control over all aspects of the script. You can run once or keep alive as a daemon. In most cases, this is the way to go.

  1. Create a .plist file according to the instructions in the Apple Dev docs here or more detail below.
  2. Place in ~/Library/LaunchAgents
  3. Log in (or run manually via launchctl load [filename.plist])

For more on launchd, the wikipedia article is quite good and describes the system and its advantages over other older systems.


Here's the specific plist file to run a script at login.

Updated 2017/09/25 for OSX El Capitan and newer (credit to José Messias Jr):

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
   <key>Label</key>
   <string>com.user.loginscript</string>
   <key>ProgramArguments</key>
   <array><string>/path/to/executable/script.sh</string></array>
   <key>RunAtLoad</key>
   <true/>
</dict>
</plist>

Replace the <string> after the Program key with your desired command (note that any script referenced by that command must be executable: chmod a+x /path/to/executable/script.sh to ensure it is for all users).

Save as ~/Library/LaunchAgents/com.user.loginscript.plist

Run launchctl load ~/Library/LaunchAgents/com.user.loginscript.plist and log out/in to test (or to test directly, run launchctl start com.user.loginscript)

Tail /var/log/system.log for error messages.

The key is that this is a User-specific launchd entry, so it will be run on login for the given user. System-specific launch daemons (placed in /Library/LaunchDaemons) are run on boot.

If you want a script to run on login for all users, I believe LoginHook is your only option, and that's probably the reason it exists.

Getters \ setters for dummies

You'd use them for instance to implement computed properties.

For example:

function Circle(radius) {
    this.radius = radius;
}

Object.defineProperty(Circle.prototype, 'circumference', {
    get: function() { return 2*Math.PI*this.radius; }
});

Object.defineProperty(Circle.prototype, 'area', {
    get: function() { return Math.PI*this.radius*this.radius; }
});

c = new Circle(10);
console.log(c.area); // Should output 314.159
console.log(c.circumference); // Should output 62.832

(CodePen)

What are my options for storing data when using React Native? (iOS and Android)

Folks above hit the right notes for storage, though if you also need to consider any PII data that needs to be stored then you can also stash into the keychain using something like https://github.com/oblador/react-native-keychain since ASyncStorage is unencrypted. It can be applied as part of the persist configuration in something like redux-persist.

What is the correct way to read a serial port using .NET framework?

I used similar code to @MethodMan but I had to keep track of the data the serial port was sending and look for a terminating character to know when the serial port was done sending data.

private string buffer { get; set; }
private SerialPort _port { get; set; }

public Port() 
{
    _port = new SerialPort();
    _port.DataReceived += new SerialDataReceivedEventHandler(dataReceived);
    buffer = string.Empty;
}

private void dataReceived(object sender, SerialDataReceivedEventArgs e)
{    
    buffer += _port.ReadExisting();

    //test for termination character in buffer
    if (buffer.Contains("\r\n"))
    {
        //run code on data received from serial port
    }
}

How to pass integer from one Activity to another?

It's simple. On the sender side, use Intent.putExtra:

Intent myIntent = new Intent(A.this, B.class);
myIntent.putExtra("intVariableName", intValue);
startActivity(myIntent);

On the receiver side, use Intent.getIntExtra:

 Intent mIntent = getIntent();
 int intValue = mIntent.getIntExtra("intVariableName", 0);

How to include another XHTML in XHTML using JSF 2.0 Facelets?

Included page:

<!-- opening and closing tags of included page -->
<ui:composition ...>
</ui:composition>

Including page:

<!--the inclusion line in the including page with the content-->
<ui:include src="yourFile.xhtml"/>
  • You start your included xhtml file with ui:composition as shown above.
  • You include that file with ui:include in the including xhtml file as also shown above.

iTerm2 keyboard shortcut - split pane navigation

I was using Terminator before, so I found it convenient to re-map Alt + arrow-key to switch between the panes. This can be done in Preferences -> Keys -> Key Mappings - press the '+' button to add a mapping. Also, in my case such a mapping was already defined in Profiles, I simply removed it.

How to get current instance name from T-SQL

SELECT @@servername will give you data as server/instanceName

To get only the instanceName you should run select @@ServiceName query .

Need to list all triggers in SQL Server database with table name and table's schema

The just above code is incorrect as shown:

SELECT 
    sysobjects.name AS trigger_name 
    --,USER_NAME(sysobjects.uid) AS trigger_owner 
    --,s.name AS table_schema 
    --,OBJECT_NAME(parent_obj) AS table_name 
    --,OBJECTPROPERTY( id, 'ExecIsUpdateTrigger') AS isupdate 
    --,OBJECTPROPERTY( id, 'ExecIsDeleteTrigger') AS isdelete 
    --,OBJECTPROPERTY( id, 'ExecIsInsertTrigger') AS isinsert 
    --,OBJECTPROPERTY( id, 'ExecIsAfterTrigger') AS isafter 
    --,OBJECTPROPERTY( id, 'ExecIsInsteadOfTrigger') AS isinsteadof 
    --,OBJECTPROPERTY(id, 'ExecIsTriggerDisabled') AS [disabled] 
FROM sysobjects 
/*
INNER JOIN sysusers 
    ON sysobjects.uid = sysusers.uid 
*/  
INNER JOIN sys.tables t 
    ON sysobjects.parent_obj = t.object_id 

INNER JOIN sys.schemas s 
    ON t.schema_id = s.schema_id 
WHERE sysobjects.type = 'TR' 
EXCEPT
SELECT OBJECT_NAME(parent_id) as Table_Name FROM sys.triggers

jQuery iframe load() event?

Without code in iframe + animate:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.0/jquery.min.js"></script>
<script language="javascript" type="text/javascript">

function resizeIframe(obj) {

    jQuery(document).ready(function($) {

        $(obj).animate({height: obj.contentWindow.document.body.scrollHeight + 'px'}, 500)

    });

}    
</script>
<iframe width="100%" src="iframe.html" height="0" frameborder="0" scrolling="no" onload="resizeIframe(this)" >

Writing file to web server - ASP.NET

There are methods like WriteAllText in the File class for common operations on files.

Use the MapPath method to get the physical path for a file in your web application.

File.WriteAllText(Server.MapPath("~/data.txt"), TextBox1.Text);

Creating a Plot Window of a Particular Size

As the accepted solution of @Shane is not supported in RStudio (see here) as of now (Sep 2015), I would like to add an advice to @James Thompson answer regarding workflow:

If you use SumatraPDF as viewer you do not need to close the PDF file before making changes to it. Sumatra does not put a opened file in read-only and thus does not prevent it from being overwritten. Therefore, once you opened your PDF file with Sumatra, changes out of RStudio (or any other R IDE) are immediately displayed in Sumatra.

Error "initializer element is not constant" when trying to initialize variable with const

In C language, objects with static storage duration have to be initialized with constant expressions, or with aggregate initializers containing constant expressions.

A "large" object is never a constant expression in C, even if the object is declared as const.

Moreover, in C language, the term "constant" refers to literal constants (like 1, 'a', 0xFF and so on), enum members, and results of such operators as sizeof. Const-qualified objects (of any type) are not constants in C language terminology. They cannot be used in initializers of objects with static storage duration, regardless of their type.

For example, this is NOT a constant

const int N = 5; /* `N` is not a constant in C */

The above N would be a constant in C++, but it is not a constant in C. So, if you try doing

static int j = N; /* ERROR */

you will get the same error: an attempt to initialize a static object with a non-constant.

This is the reason why, in C language, we predominantly use #define to declare named constants, and also resort to #define to create named aggregate initializers.

Error :The remote server returned an error: (401) Unauthorized

The answers did help, but I think a full implementation of this will help a lot of people.

using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Text;

namespace Dom
{
    class Dom
    {
        public static string make_Sting_From_Dom(string reportname)
        {
            try
            {
                WebClient client = new WebClient();
                client.Credentials = CredentialCache.DefaultCredentials;
                // Retrieve resource as a stream               
                Stream data = client.OpenRead(new Uri(reportname.Trim()));
                // Retrieve the text
                StreamReader reader = new StreamReader(data);
                string htmlContent = reader.ReadToEnd();
                string mtch = "TILDE";
                bool b = htmlContent.Contains(mtch);

                if (b)
                {
                    int index = htmlContent.IndexOf(mtch);
                    if (index >= 0)
                        Console.WriteLine("'{0} begins at character position {1}",
                        mtch, index + 1);
                }
                // Cleanup
                data.Close();
                reader.Close();
                return htmlContent;
            }
            catch (Exception)
            {
                throw;
            }
        }

        static void Main(string[] args)
        {
            make_Sting_From_Dom("https://www.w3.org/TR/PNG/iso_8859-1.txt");
        }
    }
}

How to restrict UITextField to take only numbers in Swift?

Tested in swift 3.0

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool

{         
    let numberOnly = NSCharacterSet.init(charactersIn: "0123456789")
    let stringFromTextField = NSCharacterSet.init(charactersIn: string)
    let strValid = numberOnly.isSuperset(of: stringFromTextField as CharacterSet)

     return strValid
 }

The service cannot accept control messages at this time

I killed related w3wp.exe (on a friends' advise) at task manager and it worked.

Note: Use at your own risk. Be careful picking which one to kill.

Invoke a second script with arguments from a script

Here's an answer covering the more general question of calling another PS script from a PS script, as you may do if you were composing your scripts of many little, narrow-purpose scripts.

I found it was simply a case of using dot-sourcing. That is, you just do:

# This is Script-A.ps1

. ./Script-B.ps1 -SomeObject $variableFromScriptA -SomeOtherParam 1234;

I found all the Q/A very confusing and complicated and eventually landed upon the simple method above, which is really just like calling another script as if it was a function in the original script, which I seem to find more intuitive.

Dot-sourcing can "import" the other script in its entirety, using:

. ./Script-B.ps1

It's now as if the two files are merged.

Ultimately, what I was really missing is the notion that I should be building a module of reusable functions.

Counting words in string

One more way to count words in a string. This code counts words that contain only alphanumeric characters and "_", "’", "-", "'" chars.

function countWords(str) {
  var matches = str.match(/[\w\d\’\'-]+/gi);
  return matches ? matches.length : 0;
}

c# foreach (property in object)... Is there a simple way of doing this?

Give this a try:

foreach (PropertyInfo propertyInfo in obj.GetType().GetProperties())
{
   // do stuff here
}

Also please note that Type.GetProperties() has an overload which accepts a set of binding flags so you can filter out properties on a different criteria like accessibility level, see MSDN for more details: Type.GetProperties Method (BindingFlags) Last but not least don't forget to add the "system.Reflection" assembly reference.

For instance to resolve all public properties:

foreach (var propertyInfo in obj.GetType()
                                .GetProperties(
                                        BindingFlags.Public 
                                        | BindingFlags.Instance))
{
   // do stuff here
}

Please let me know whether this works as expected.

How many characters can you store with 1 byte?

2^8 = 256 Characters. A character in binary is a series of 8 ( 0 or 1).

   |----------------------------------------------------------|
   |                                                          |
   | Type    | Storage |  Minimum Value    | Maximum Value    |
   |         | (Bytes) | (Signed/Unsigned) | (Signed/Unsigned)|
   |         |         |                   |                  |
   |---------|---------|-------------------|------------------|
   |         |         |                   |                  |
   |         |         |                   |                  |
   | TINYINT |  1      |      -128 - 0     |  127 - 255       |
   |         |         |                   |                  |
   |----------------------------------------------------------|

How to align form at the center of the page in html/css

Wrap the <form> element inside a div container and apply css to the div instead which makes things easier.

_x000D_
_x000D_
#aDiv{width: 300px; height: 300px; margin: 0 auto;}
_x000D_
<html>_x000D_
_x000D_
<head></head>_x000D_
_x000D_
<body>_x000D_
  <div>_x000D_
    <form>_x000D_
      <div id="aDiv">_x000D_
        <table>_x000D_
          <tr>_x000D_
            <td>Name :</td>_x000D_
            <td>_x000D_
              <input type="text" name="name">_x000D_
            </td>_x000D_
            <br>_x000D_
          </tr>_x000D_
          <tr>_x000D_
            <td>Email :</td>_x000D_
            <td>_x000D_
              <input type="text" name="email">_x000D_
            </td>_x000D_
            <br>_x000D_
          </tr>_x000D_
          <tr>_x000D_
            <td>Password :</td>_x000D_
            <td>_x000D_
              <input type="password" name="pwd">_x000D_
            </td>_x000D_
            <br>_x000D_
          </tr>_x000D_
          <tr>_x000D_
            <td>Confirm Password :</td>_x000D_
            <td>_x000D_
              <input type="password" name="cpwd">_x000D_
              <br>_x000D_
          </tr>_x000D_
          <tr>_x000D_
            <td>_x000D_
              <input type="submit" value="Submit">_x000D_
            </td>_x000D_
          </tr>_x000D_
        </table>_x000D_
      </div>_x000D_
    </form>_x000D_
  </div>_x000D_
</body>_x000D_
_x000D_
</html>
_x000D_
_x000D_
_x000D_

Run a JAR file from the command line and specify classpath

You can do these in unix shell:

java -cp MyJar.jar:lib/* com.somepackage.subpackage.Main

You can do these in windows powershell:

java -cp "MyJar.jar;lib\*" com.somepackage.subpackage.Main

How to set the maximum memory usage for JVM?

The answer above is kind of correct, you can't gracefully control how much native memory a java process allocates. It depends on what your application is doing.

That said, depending on platform, you may be able to do use some mechanism, ulimit for example, to limit the size of a java or any other process.

Just don't expect it to fail gracefully if it hits that limit. Native memory allocation failures are much harder to handle than allocation failures on the java heap. There's a fairly good chance the application will crash but depending on how critical it is to the system to keep the process size down that might still suit you.

Check to see if cURL is installed locally?

Another way, say in CentOS, is:

$ yum list installed '*curl*'
Loaded plugins: aliases, changelog, fastestmirror, kabi, langpacks, priorities, tmprepo, verify,
              : versionlock
Loading support for Red Hat kernel ABI
Determining fastest mirrors
google-chrome                                                                                    3/3
152 packages excluded due to repository priority protections
Installed Packages
curl.x86_64                                        7.29.0-42.el7                                @base
libcurl.x86_64                                     7.29.0-42.el7                                @base
libcurl-devel.x86_64                               7.29.0-42.el7                                @base
python-pycurl.x86_64                               7.19.0-19.el7                                @base

system("pause"); - Why is it wrong?

As listed on the other answers, there are many reasons you can find to avoid this. It all boils down to one reason that makes the rest moot. The System() function is inherently insecure/untrusted, and should not be introduced into a program unless necessary.

For a student assignment, this condition was never met, and for this reason I would fail an assignment without even running the program if a call to this method was present. (This was made clear from the start.)

Python Pandas Replacing Header with Top Row

--another way to do this


df.columns = df.iloc[0]
df = df.reindex(df.index.drop(0)).reset_index(drop=True)
df.columns.name = None

    Sample Number  Group Number  Sample Name  Group Name
0             1.0           1.0          s_1         g_1
1             2.0           1.0          s_2         g_1
2             3.0           1.0          s_3         g_1
3             4.0           2.0          s_4         g_2

If you like it hit up arrow. Thanks

How to read and write excel file

For reading a xlsx file we can use Apache POI libs Try this:

public static void readXLSXFile() throws IOException
    {
        InputStream ExcelFileToRead = new FileInputStream("C:/Test.xlsx");
        XSSFWorkbook  wb = new XSSFWorkbook(ExcelFileToRead);

        XSSFWorkbook test = new XSSFWorkbook(); 

        XSSFSheet sheet = wb.getSheetAt(0);
        XSSFRow row; 
        XSSFCell cell;

        Iterator rows = sheet.rowIterator();

        while (rows.hasNext())
        {
            row=(XSSFRow) rows.next();
            Iterator cells = row.cellIterator();
            while (cells.hasNext())
            {
                cell=(XSSFCell) cells.next();

                if (cell.getCellType() == XSSFCell.CELL_TYPE_STRING)
                {
                    System.out.print(cell.getStringCellValue()+" ");
                }
                else if(cell.getCellType() == XSSFCell.CELL_TYPE_NUMERIC)
                {
                    System.out.print(cell.getNumericCellValue()+" ");
                }
                else
                {
                    //U Can Handel Boolean, Formula, Errors
                }
            }
            System.out.println();
        }

    }

How to make picturebox transparent?

Just use the Form Paint method and draw every Picturebox on it, it allows transparency :

    private void frmGame_Paint(object sender, PaintEventArgs e)
    {
        DoubleBuffered = true;
        for (int i = 0; i < Controls.Count; i++)
            if (Controls[i].GetType() == typeof(PictureBox))
            {
                var p = Controls[i] as PictureBox;
                p.Visible = false;
                e.Graphics.DrawImage(p.Image, p.Left, p.Top, p.Width, p.Height);
            }
    }

.rar, .zip files MIME Type

You should not trust $_FILES['upfile']['mime'], check MIME type by yourself. For that purpose, you may use fileinfo extension, enabled by default as of PHP 5.3.0.

  $fileInfo = new finfo(FILEINFO_MIME_TYPE);
  $fileMime = $fileInfo->file($_FILES['upfile']['tmp_name']);
  $validMimes = array( 
    'zip' => 'application/zip',
    'rar' => 'application/x-rar',
  );

  $fileExt = array_search($fileMime, $validMimes, true);
  if($fileExt != 'zip' && $fileExt != 'rar')
    throw new RuntimeException('Invalid file format.');

NOTE: Don't forget to enable the extension in your php.ini and restart your server:

extension=php_fileinfo.dll

Combating AngularJS executing controller twice

I just went through this, but the issue was different from the accepted answer. I'm really leaving this here for my future self, to include the steps I went through to fix it.

  1. Remove redundant controller declarations
  2. Check trailing slashes in routes
  3. Check for ng-ifs
  4. Check for any unnecessary wrapping ng-view calls (I accidentally had left in an ng-view that was wrapping my actual ng-view. This resulted in three calls to my controllers.)
  5. If you are on Rails, you should remove the turbolinks gem from your application.js file. I wasted a whole day to discover that. Found answer here.
  6. Initializing the app twice with ng-app and with bootstrap. Combating AngularJS executing controller twice
  7. When using $compile on whole element in 'link'-function of directive that also has its own controller defined and uses callbacks of this controller in template via ng-click etc. Found answer here.

How to generate the JPA entity Metamodel?

For eclipselink, only the following dependency is sufficient to generate metamodel. Nothing else is needed.

    <dependency>
        <groupId>org.eclipse.persistence</groupId>
        <artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId>
        <version>2.5.1</version>
        <scope>provided</scope>
    </dependency>

How to update the value stored in Dictionary in C#?

You can follow this approach:

void addOrUpdate(Dictionary<int, int> dic, int key, int newValue)
{
    int val;
    if (dic.TryGetValue(key, out val))
    {
        // yay, value exists!
        dic[key] = val + newValue;
    }
    else
    {
        // darn, lets add the value
        dic.Add(key, newValue);
    }
}

The edge you get here is that you check and get the value of corresponding key in just 1 access to the dictionary. If you use ContainsKey to check the existance and update the value using dic[key] = val + newValue; then you are accessing the dictionary twice.

How to check if a value is not null and not empty string in JS

_x000D_
_x000D_
function validateAttrs(arg1, arg2, arg3,arg4){
    var args = Object.values(arguments);
    return (args.filter(x=> x===null || !x)).length<=0
}
console.log(validateAttrs('1',2, 3, 4));
console.log(validateAttrs('1',2, 3, null));
console.log(validateAttrs('1',undefined, 3, 4));
console.log(validateAttrs('1',2, '', 4));
console.log(validateAttrs('1',2, 3, null));
_x000D_
_x000D_
_x000D_

Understanding colors on Android (six characters)

at new chrome version (maybe 67.0.3396.62) , CSS hex color can use this model display,

eg:

div{
  background-color:#FF00FFcc;
}

cc is opacity , but old chrome not support that mod

UITableView Cell selected Color?

In case of custom cell class. Just override:

- (void)setSelected:(BOOL)selected animated:(BOOL)animated {
    [super setSelected:selected animated:animated];

    // Configure the view for the selected state

    if (selected) {
        [self setBackgroundColor: CELL_SELECTED_BG_COLOR];
        [self.contentView setBackgroundColor: CELL_SELECTED_BG_COLOR];
    }else{
        [self setBackgroundColor: [UIColor clearColor]];
        [self.contentView setBackgroundColor: [UIColor clearColor]];
    }
}

Convert javascript object or array to json for ajax data

I'm not entirely sure but I think you are probably surprised at how arrays are serialized in JSON. Let's isolate the problem. Consider following code:

var display = Array();
display[0] = "none";
display[1] = "block";
display[2] = "none";

console.log( JSON.stringify(display) );

This will print:

["none","block","none"]

This is how JSON actually serializes array. However what you want to see is something like:

{"0":"none","1":"block","2":"none"}

To get this format you want to serialize object, not array. So let's rewrite above code like this:

var display2 = {};
display2["0"] = "none";
display2["1"] = "block";
display2["2"] = "none";

console.log( JSON.stringify(display2) );

This will print in the format you want.

You can play around with this here: http://jsbin.com/oDuhINAG/1/edit?js,console

How to fix "Headers already sent" error in PHP

Generally this error arise when we send header after echoing or printing. If this error arise on a specific page then make sure that page is not echoing anything before calling to start_session().

Example of Unpredictable Error:

 <?php //a white-space before <?php also send for output and arise error
session_start();
session_regenerate_id();

//your page content

One more example:

<?php
includes 'functions.php';
?> <!-- This new line will also arise error -->
<?php
session_start();
session_regenerate_id();

//your page content

Conclusion: Do not output any character before calling session_start() or header() functions not even a white-space or new-line

Why are Python's 'private' methods not actually private?

From http://www.faqs.org/docs/diveintopython/fileinfo_private.html

Strictly speaking, private methods are accessible outside their class, just not easily accessible. Nothing in Python is truly private; internally, the names of private methods and attributes are mangled and unmangled on the fly to make them seem inaccessible by their given names. You can access the __parse method of the MP3FileInfo class by the name _MP3FileInfo__parse. Acknowledge that this is interesting, then promise to never, ever do it in real code. Private methods are private for a reason, but like many other things in Python, their privateness is ultimately a matter of convention, not force.

How to solve WAMP and Skype conflict on Windows 7?

  1. open skype
  2. click tools and go to options
  3. click advanced option from left side
  4. click connection
  5. unchecked (Use port 80 and 443 as alternatives for incoming connection)

"OverflowError: Python int too large to convert to C long" on windows but not mac

Could anyone help explain why

In Python 2 a python "int" was equivalent to a C long. In Python 3 an "int" is an arbitrary precision type but numpy still uses "int" it to represent the C type "long" when creating arrays.

The size of a C long is platform dependent. On windows it is always 32-bit. On unix-like systems it is normally 32 bit on 32 bit systems and 64 bit on 64 bit systems.

or give a solution for the code on windows? Thanks so much!

Choose a data type whose size is not platform dependent. You can find the list at https://docs.scipy.org/doc/numpy/reference/arrays.scalars.html#arrays-scalars-built-in the most sensible choice would probably be np.int64

php - add + 7 days to date format mm dd, YYYY

$date = "Mar 03, 2011";
$date = strtotime($date);
$date = strtotime("+7 day", $date);
echo date('M d, Y', $date);

Is there a cross-browser onload event when clicking the back button?

jQuery's ready event was created for just this sort of issue. You may want to dig into the implementation to see what is going on under the covers.

Can I check if Bootstrap Modal Shown / Hidden?

All Bootstrap versions:

var isShown = $('.modal').hasClass('in') || $('.modal').hasClass('show')

To just close it independent of state and version:

$('.modal button.close').click()

more info

Bootstrap 3 and before

var isShown = $('.modal').hasClass('in')

Bootstrap 4

var isShown = $('.modal').hasClass('show')

.htaccess mod_rewrite - how to exclude directory from rewrite rule

add a condition to check for the admin directory, something like:

RewriteCond %{REQUEST_URI} !^/?(admin|user)/
RewriteRule ^([^/] )/([^/] )\.html$ index.php?lang=$1&mod=$2 [L]

RewriteCond %{REQUEST_URI} !^/?(admin|user)/
RewriteRule ^([^/] )/$ index.php?lang=$1&mod=home [L]

Error:Execution failed for task ':app:transformClassesWithDexForDebug' in android studio

This can be because of following reason:

  1. one of the jar files inside project was using an older version of google play services.

  2. use multiDexEnabled true in defaultconfig

  3. Be specific with classes you add in dependencies. like

    compile 'com.google.android.gms:play-services-maps:8.4.0'

Not like compile 'com.google.android.gms:play-services:+'

Pure css close button

Just a thought - if you're not targeting IE7, you could get away with any image being base64-encoded and embedded into css. I'm assuming your goal is to avoid an unnecessary http request rather than to actually make a css button as its own goal.

Insert current date in datetime format mySQL

$date = date('Y-m-d H:i:s'); with the type: 'datetime' worked very good for me as i wanted to print whole date and timestamp..

$date = date('Y-m-d H:i:s'); $stmtc->bindParam(2,$date);

How do I stop a web page from scrolling to the top when a link is clicked that triggers JavaScript?

Create a page which contains two links- one at the top and one at the bottom. On clicking the top link, the page has to scroll down to the bottom of the page where bottom link is present. On clicking the bottom link, the page has to scroll up to the top of the page.

Android ADB stop application command like "force-stop" for non rooted device

The first way
Needs root

Use kill:

adb shell ps => Will list all running processes on the device and their process ids
adb shell kill <PID> => Instead of <PID> use process id of your application

The second way
In Eclipse open DDMS perspective.
In Devices view you will find all running processes.
Choose the process and click on Stop.

enter image description here

The third way
It will kill only background process of an application.

adb shell am kill [options] <PACKAGE> => Kill all processes associated with (the app's package name). This command kills only processes that are safe to kill and that will not impact the user experience.
Options are:

--user | all | current: Specify user whose processes to kill; all users if not specified.

The fourth way
Needs root

adb shell pm disable <PACKAGE> => Disable the given package or component (written as "package/class").

The fifth way
Note that run-as is only supported for apps that are signed with debug keys.

run-as <package-name> kill <pid>

The sixth way
Introduced in Honeycomb

adb shell am force-stop <PACKAGE> => Force stop everything associated with (the app's package name).

P.S.: I know that the sixth method didn't work for you, but I think that it's important to add this method to the list, so everyone will know it.

How to script FTP upload and download?

Try manually:

$ ftp www.domainhere.com 
> useridhere
> passwordhere
> put test.txt
> bye
> pause

Prevent RequireJS from Caching Required Scripts

This is how I do it in Django / Flask (can be easily adapted to other languages / VCS systems):

In your config.py (I use this in python3, so you may need to tweak the encoding in python2)

import subprocess
GIT_HASH = subprocess.check_output(['git', 'rev-parse', 'HEAD']).strip().decode('utf-8')

Then in your template:

{% if config.DEBUG %}
     require.config({urlArgs: "bust=" + (new Date().getTime())});
{% else %}
    require.config({urlArgs: "bust=" + {{ config.GIT_HASH|tojson }}});
{% endif %}
  • Doesn't require manual build process
  • Only runs git rev-parse HEAD once when the app starts, and stores it in the config object

SHA512 vs. Blowfish and Bcrypt

It should suffice to say whether bcrypt or SHA-512 (in the context of an appropriate algorithm like PBKDF2) is good enough. And the answer is yes, either algorithm is secure enough that a breach will occur through an implementation flaw, not cryptanalysis.

If you insist on knowing which is "better", SHA-512 has had in-depth reviews by NIST and others. It's good, but flaws have been recognized that, while not exploitable now, have led to the the SHA-3 competition for new hash algorithms. Also, keep in mind that the study of hash algorithms is "newer" than that of ciphers, and cryptographers are still learning about them.

Even though bcrypt as a whole hasn't had as much scrutiny as Blowfish itself, I believe that being based on a cipher with a well-understood structure gives it some inherent security that hash-based authentication lacks. Also, it is easier to use common GPUs as a tool for attacking SHA-2–based hashes; because of its memory requirements, optimizing bcrypt requires more specialized hardware like FPGA with some on-board RAM.


Note: bcrypt is an algorithm that uses Blowfish internally. It is not an encryption algorithm itself. It is used to irreversibly obscure passwords, just as hash functions are used to do a "one-way hash".

Cryptographic hash algorithms are designed to be impossible to reverse. In other words, given only the output of a hash function, it should take "forever" to find a message that will produce the same hash output. In fact, it should be computationally infeasible to find any two messages that produce the same hash value. Unlike a cipher, hash functions aren't parameterized with a key; the same input will always produce the same output.

If someone provides a password that hashes to the value stored in the password table, they are authenticated. In particular, because of the irreversibility of the hash function, it's assumed that the user isn't an attacker that got hold of the hash and reversed it to find a working password.

Now consider bcrypt. It uses Blowfish to encrypt a magic string, using a key "derived" from the password. Later, when a user enters a password, the key is derived again, and if the ciphertext produced by encrypting with that key matches the stored ciphertext, the user is authenticated. The ciphertext is stored in the "password" table, but the derived key is never stored.

In order to break the cryptography here, an attacker would have to recover the key from the ciphertext. This is called a "known-plaintext" attack, since the attack knows the magic string that has been encrypted, but not the key used. Blowfish has been studied extensively, and no attacks are yet known that would allow an attacker to find the key with a single known plaintext.

So, just like irreversible algorithms based cryptographic digests, bcrypt produces an irreversible output, from a password, salt, and cost factor. Its strength lies in Blowfish's resistance to known plaintext attacks, which is analogous to a "first pre-image attack" on a digest algorithm. Since it can be used in place of a hash algorithm to protect passwords, bcrypt is confusingly referred to as a "hash" algorithm itself.

Assuming that rainbow tables have been thwarted by proper use of salt, any truly irreversible function reduces the attacker to trial-and-error. And the rate that the attacker can make trials is determined by the speed of that irreversible "hash" algorithm. If a single iteration of a hash function is used, an attacker can make millions of trials per second using equipment that costs on the order of $1000, testing all passwords up to 8 characters long in a few months.

If however, the digest output is "fed back" thousands of times, it will take hundreds of years to test the same set of passwords on that hardware. Bcrypt achieves the same "key strengthening" effect by iterating inside its key derivation routine, and a proper hash-based method like PBKDF2 does the same thing; in this respect, the two methods are similar.

So, my recommendation of bcrypt stems from the assumptions 1) that a Blowfish has had a similar level of scrutiny as the SHA-2 family of hash functions, and 2) that cryptanalytic methods for ciphers are better developed than those for hash functions.

How to send cookies in a post request with the Python Requests library?

Just to extend on the previous answer, if you are linking two requests together and want to send the cookies returned from the first one to the second one (for example, maintaining a session alive across requests) you can do:

import requests
r1 = requests.post('http://www.yourapp.com/login')
r2 = requests.post('http://www.yourapp.com/somepage',cookies=r1.cookies)

Efficiently updating database using SQLAlchemy ORM

session.query(Clients).filter(Clients.id == client_id_list).update({'status': status})
session.commit()

Try this =)

Check an integer value is Null in c#

There is already a correct answer from Adam, but you have another option to refactor your code:

if (Age.GetValueOrDefault() == 0)
{
    // it's null or 0
}

How to read data from java properties file using Spring Boot

We can read properties file in spring boot using 3 way

1. Read value from application.properties Using @Value

map key as

public class EmailService {

 @Value("${email.username}")
 private String username;

}

2. Read value from application.properties Using @ConfigurationProperties

In this we will map prefix of key using ConfigurationProperties and key name is same as field of class

  @Component
   @ConfigurationProperties("email")
    public class EmailConfig {

        private String   username;
    }

3. Read application.properties Using using Environment object

public class EmailController {

@Autowired
private Environment env;

@GetMapping("/sendmail")
public void sendMail(){     
    System.out.println("reading value from application properties file  using Environment ");
    System.out.println("username ="+ env.getProperty("email.username"));
    System.out.println("pwd ="+ env.getProperty("email.pwd"));
}

Reference : how to read value from application.properties in spring boot

How to convert string to Title Case in Python?

just use .title(), and it will convert first letter of every word in capital, rest in small:

>>> a='mohs shahid ss'
>>> a.title()
'Mohs Shahid Ss'
>>> a='TRUE'
>>> b=a.title()
>>> b
'True'
>>> eval(b)
True

JQuery post JSON object to a server

It is also possible to use FormData(). But you need to set contentType as false:

var data = new FormData();
data.append('name', 'Bob'); 

function sendData() {
    $.ajax({
        url: '/helloworld',
        type: 'POST',
        contentType: false,
        data: data,
        dataType: 'json'
    });
}

Block direct access to a file over http but allow php script access

How about custom module based .htaccess script (like its used in CodeIgniter)? I tried and it worked good in CodeIgniter apps. Any ideas to use it on other apps?

<IfModule authz_core_module>
    Require all denied
</IfModule>
<IfModule !authz_core_module>
    Deny from all
</IfModule>

Error Domain=NSURLErrorDomain Code=-1005 "The network connection was lost."

I faced the same issue while calling using my company's server from iOS 12 app with a physical device. The problem was that the server hard disk was full. Freeing space in the server solved the problem.

I found the same error in another situation I think due to a timeout not parametrizable through the standard Networking API provided by Apple (URLSession.timeoutIntervalForRequest and URLSession.timeoutIntervalForResource). Even there.. made server answer faster solved the problem

Fragment Inside Fragment

enter image description here

I needed some more context, so I made an example to show how this is done. The most helpful thing I read while preparing was this:

Activity

activity_main.xml

Add a FrameLayout to your activity to hold the parent fragment.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="match_parent">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Activity"/>

    <FrameLayout
        android:id="@+id/parent_fragment_container"
        android:layout_width="match_parent"
        android:layout_height="200dp"/>

 </LinearLayout>

MainActivity.java

Load the parent fragment and implement the fragment listeners. (See fragment communication.)

import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity implements ParentFragment.OnFragmentInteractionListener, ChildFragment.OnFragmentInteractionListener {

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

        // Begin the transaction
        FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
        ft.replace(R.id.parent_fragment_container, new ParentFragment());
        ft.commit();
    }

    @Override
    public void messageFromParentFragment(Uri uri) {
        Log.i("TAG", "received communication from parent fragment");
    }

    @Override
    public void messageFromChildFragment(Uri uri) {
        Log.i("TAG", "received communication from child fragment");
    }
}

Parent Fragment

fragment_parent.xml

Add another FrameLayout container for the child fragment.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:layout_margin="20dp"
              android:background="#91d0c2">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Parent fragment"/>

    <FrameLayout
        android:id="@+id/child_fragment_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

    </FrameLayout>

</LinearLayout>

ParentFragment.java

Use getChildFragmentManager in onViewCreated to set up the child fragment.

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentTransaction;    

public class ParentFragment extends Fragment {

    private OnFragmentInteractionListener mListener;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_parent, container, false);
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        Fragment childFragment = new ChildFragment();
        FragmentTransaction transaction = getChildFragmentManager().beginTransaction();
        transaction.replace(R.id.child_fragment_container, childFragment).commit();
    }


    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        if (context instanceof OnFragmentInteractionListener) {
            mListener = (OnFragmentInteractionListener) context;
        } else {
            throw new RuntimeException(context.toString()
                    + " must implement OnFragmentInteractionListener");
        }
    }

    @Override
    public void onDetach() {
        super.onDetach();
        mListener = null;
    }

    public interface OnFragmentInteractionListener {
        // TODO: Update argument type and name
        void messageFromParentFragment(Uri uri);
    }
}

Child Fragment

fragment_child.xml

There is nothing special here.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:layout_margin="20dp"
              android:background="#f1ff91">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Child fragment"/>
</LinearLayout>

ChildFragment.java

There is nothing too special here, either.

import android.support.v4.app.Fragment;

public class ChildFragment extends Fragment {

    private OnFragmentInteractionListener mListener;


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_child, container, false);
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        if (context instanceof OnFragmentInteractionListener) {
            mListener = (OnFragmentInteractionListener) context;
        } else {
            throw new RuntimeException(context.toString()
                    + " must implement OnFragmentInteractionListener");
        }
    }

    @Override
    public void onDetach() {
        super.onDetach();
        mListener = null;
    }


    public interface OnFragmentInteractionListener {
        // TODO: Update argument type and name
        void messageFromChildFragment(Uri uri);
    }
}

Notes

  • The support library is being used so that nested fragments can be used before Android 4.2.

Validate that a string is a positive integer

Just to build on VisioN's answer above, if you are using the jQuery validation plugin you could use this:

$(document).ready(function() {
    $.validator.addMethod('integer', function(value, element, param) {
        return (value >>> 0 === parseFloat(value) && value > 0);
    }, 'Please enter a non zero integer value!');
}

Then you could use in your normal rules set or add it dynamically this way:

$("#positiveIntegerField").rules("add", {required:true, integer:true});

Abstract variables in Java?

Change the code to:

public abstract class clsAbstractTable {
  protected String TAG;
  public abstract void init();
}

public class clsContactGroups extends clsAbstractTable {
  public String doSomething() {
    return TAG + "<something else>";
  }
}

That way, all of the classes who inherit this class will have this variable. You can do 200 subclasses and still each one of them will have this variable.

Side note: do not use CAPS as variable name; common wisdom is that all caps identifiers refer to constants, i.e. non-changeable pieces of data.

writing to existing workbook using xlwt

openpyxl

# -*- coding: utf-8 -*-
import openpyxl
file = 'sample.xlsx'
wb = openpyxl.load_workbook(filename=file)
# Seleciono la Hoja
ws = wb.get_sheet_by_name('Hoja1')
# Valores a Insertar
ws['A3'] = 42
ws['A4'] = 142
# Escribirmos en el Fichero
wb.save(file)

Bad operand type for unary +: 'str'

The code works for me. (after adding missing except clause / import statements)

Did you put \ in the original code?

urlToVisit = 'http://chartapi.finance.yahoo.com/instrument/1.0/' \
              + stock + '/chartdata;type=quote;range=5d/csv'

If you omit it, it could be a cause of the exception:

>>> stock = 'GOOG'
>>> urlToVisit = 'http://chartapi.finance.yahoo.com/instrument/1.0/'
>>> + stock + '/chartdata;type=quote;range=5d/csv'
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: bad operand type for unary +: 'str'

BTW, string(e) should be str(e).

How to scroll to the bottom of a RecyclerView? scrollToPosition doesn't work

Tried a method of @galex, it worked until refactoring. So I used an answer of @yanchenko and changed a bit. Probably this is because I called scrolling from onCreateView(), where a fragment view was built (and probably didn't have right size).

private fun scrollPhotosToEnd(view: View) {
    view.recycler_view.viewTreeObserver.addOnGlobalLayoutListener(object :
        ViewTreeObserver.OnGlobalLayoutListener {
        override fun onGlobalLayout() {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
                view.recycler_view.viewTreeObserver.removeOnGlobalLayoutListener(this)
            } else {
                @Suppress("DEPRECATION")
                view.recycler_view.viewTreeObserver.removeGlobalOnLayoutListener(this)
            }
            adapter?.itemCount?.takeIf { it > 0 }?.let {
                view.recycler_view.scrollToPosition(it - 1)
            }
        }
    })
}

You can also add a check of viewTreeObserver.isAlive like in https://stackoverflow.com/a/39001731/2914140.

Spring Maven clean error - The requested profile "pom.xml" could not be activated because it does not exist

I was getting this same warning everytime I was doing 'maven clean'. I found the solution :

Step - 1 Right click on your project in Eclipse

Step - 2 Click Properties

Step - 3 Select Maven in the left hand side list.

Step - 4 You will notice "pom.xml" in the Active Maven Profiles text box on the right hand side. Clear it and click Apply.

Below is the screen shot :

Properties dialog box

Hope this helps. :)

Is there a way to get a collection of all the Models in your Rails app?

Dir.foreach("#{Rails.root.to_s}/app/models") do |model_path|
  next unless model_path.match(/.rb$/)
  model_class = model_path.gsub(/.rb$/, '').classify.constantize
  puts model_class
end

This will give to you all the model classes you have on your project.

Html.RenderPartial() syntax with Razor

Html.RenderPartial() is a void method - you can check whether a method is a void method by placing your mouse over the call to RenderPartial in your code and you will see the text (extension) void HtmlHelper.RenderPartial...

Void methods require a semicolon at the end of the calling code.

In the Webforms view engine you would have encased your Html.RenderPartial() call within the bee stings <% %>

like so

<% Html.RenderPartial("Path/to/my/partial/view"); %>

when you are using the Razor view engine the equivalent is

@{Html.RenderPartial("Path/to/my/partial/view");}

How to serialize an object into a string

XStream provides a simple utility for serializing/deserializing to/from XML, and it's very quick. Storing XML CLOBs rather than binary BLOBS is going to be less fragile, not to mention more readable.

Converting Integers to Roman Numerals - Java

Despite the fact that a lot of solutions have been already proposed.

I guess that the following one will be short and clear:

public class IntegerToRoman {
    public static String intToRoman(int number) {
        String[] thousands = {"", "M", "MM", "MMM"};
        String[] hundreds = {"", "C", "CC", "CCC", "CD", "D", "DC", "DCC", "DCCC", "CM"};
        String[] tens = {"", "X", "XX", "XXX", "XL", "L", "LX", "LXX", "LXXX", "XC"};
        String[] units = {"", "I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX"};

        return thousands[number / 1000]
                + hundreds[(number % 1000) / 100]
                + tens[(number % 100) / 10]
                + units[number % 10];
    }

    public static void main(String[] args) {
        int[] numbers = {1, 2, 3, 5, 10, 14, 17, 20, 25, 38, 49, 63, 72, 81, 97, 98, 99, 100, 101, 248, 253, 799, 1325, 1900, 2000, 2456, 1715};

        final Instant startTimeIter = Instant.now();
        for (int number : numbers) {
            System.out.printf("%4d -> %8s\n", number, intToRoman(number));
        }
        final Instant endTimeIter = Instant.now();
        System.out.printf("Elapsed time: %d ms\n\n", Duration.between(startTimeIter, endTimeIter).toMillis());
    }
}

Output:

   1 ->        I
   2 ->       II
   3 ->      III
   ...
2456 ->  MMCDLVI
1715 ->   MDCCXV
Elapsed time: 66 ms

Logic is quite simple:

  • we just go through integer number from left to right
  • and taking for each number appropriate array value (thousands, hundrets...)
  • this method could convert till 3000 number

Get paragraph text inside an element

Add an Id property into the P tag with value like text or something:

function gettext() {
    var amount = document.getElementById('text').value;
}

Can the jQuery UI Datepicker be made to disable Saturdays and Sundays (and holidays)?

These answers were very helpful. Thank you.

My contribution below adds an array where multiple days can return false (we're closed every Tuesday, Wednesday and Thursday). And I bundled the specific dates plus years and the no-weekends functions.

If you want weekends off, add [Saturday], [Sunday] to the closedDays array.

$(document).ready(function(){

    $("#datepicker").datepicker({
        beforeShowDay: nonWorkingDates,
        numberOfMonths: 1,
        minDate: '05/01/09',
        maxDate: '+2M',
        firstDay: 1
    });

    function nonWorkingDates(date){
        var day = date.getDay(), Sunday = 0, Monday = 1, Tuesday = 2, Wednesday = 3, Thursday = 4, Friday = 5, Saturday = 6;
        var closedDates = [[7, 29, 2009], [8, 25, 2010]];
        var closedDays = [[Monday], [Tuesday]];
        for (var i = 0; i < closedDays.length; i++) {
            if (day == closedDays[i][0]) {
                return [false];
            }

        }

        for (i = 0; i < closedDates.length; i++) {
            if (date.getMonth() == closedDates[i][0] - 1 &&
            date.getDate() == closedDates[i][1] &&
            date.getFullYear() == closedDates[i][2]) {
                return [false];
            }
        }

        return [true];
    }




});

What is {this.props.children} and when you should use it?

I assume you're seeing this in a React component's render method, like this (edit: your edited question does indeed show that):

_x000D_
_x000D_
class Example extends React.Component {_x000D_
  render() {_x000D_
    return <div>_x000D_
      <div>Children ({this.props.children.length}):</div>_x000D_
      {this.props.children}_x000D_
    </div>;_x000D_
  }_x000D_
}_x000D_
_x000D_
class Widget extends React.Component {_x000D_
  render() {_x000D_
    return <div>_x000D_
      <div>First <code>Example</code>:</div>_x000D_
      <Example>_x000D_
        <div>1</div>_x000D_
        <div>2</div>_x000D_
        <div>3</div>_x000D_
      </Example>_x000D_
      <div>Second <code>Example</code> with different children:</div>_x000D_
      <Example>_x000D_
        <div>A</div>_x000D_
        <div>B</div>_x000D_
      </Example>_x000D_
    </div>;_x000D_
  }_x000D_
}_x000D_
_x000D_
ReactDOM.render(_x000D_
  <Widget/>,_x000D_
  document.getElementById("root")_x000D_
);
_x000D_
<div id="root"></div>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
_x000D_
_x000D_
_x000D_

children is a special property of React components which contains any child elements defined within the component, e.g. the divs inside Example above. {this.props.children} includes those children in the rendered result.

...what are the situations to use the same

You'd do it when you want to include the child elements in the rendered output directly, unchanged; and not if you didn't.

How is an HTTP POST request made in node.js?

Axios is a promise based HTTP client for the browser and Node.js. Axios makes it easy to send asynchronous HTTP requests to REST endpoints and perform CRUD operations. It can be used in plain JavaScript or with a library such as Vue or React.

const axios = require('axios');

        var dataToPost = {
          email: "your email",
          password: "your password"
        };

        let axiosConfiguration = {
          headers: {
              'Content-Type': 'application/json;charset=UTF-8',
              "Access-Control-Allow-Origin": "*",
          }
        };

        axios.post('endpoint or url', dataToPost, axiosConfiguration)
        .then((res) => {
          console.log("Response: ", res);
        })
        .catch((err) => {
          console.log("error: ", err);
        })

Getting NetworkCredential for current user (C#)

If the web service being invoked uses windows integrated security, creating a NetworkCredential from the current WindowsIdentity should be sufficient to allow the web service to use the current users windows login. However, if the web service uses a different security model, there isn't any way to extract a users password from the current identity ... that in and of itself would be insecure, allowing you, the developer, to steal your users passwords. You will likely need to provide some way for your user to provide their password, and keep it in some secure cache if you don't want them to have to repeatedly provide it.

Edit: To get the credentials for the current identity, use the following:

Uri uri = new Uri("http://tempuri.org/");
ICredentials credentials = CredentialCache.DefaultCredentials;
NetworkCredential credential = credentials.GetCredential(uri, "Basic");

What should I do when 'svn cleanup' fails?

When starting all over is not an option...

I deleted the log file in the .svn directory (I also deleted the offending file in .svn/props-base), did a cleanup, and resumed my update.

Running Python code in Vim

Just go to normal mode by pressing <esc> and type:

! clear; python %

enter image description here

Step by step explanation:

! allows you to run a terminal command

clear will empty your terminal screen

; ends the first command, allowing you to introduce a second command

python will use python to run your script (it could be replaced with ruby for example)

% concats the current filename, passing it as a parameter to the python command

Java NoSuchAlgorithmException - SunJSSE, sun.security.ssl.SSLContextImpl$DefaultSSLContext

I had the similar issue. The problem was in the passwords: the Keystore and private key used different passwords. (KeyStore explorer was used)

After creating Keystore with the same password as private key had the issue was resolved.

Convert list to dictionary using linq and not worrying about duplicates

This should work with lambda expression:

personList.Distinct().ToDictionary(i => i.FirstandLastName, i => i);

How to set up datasource with Spring for HikariCP?

I have recently migrated from C3P0 to HikariCP in a Spring and Hibernate based project and it was not as easy as I had imagined and here I am sharing my findings.

For Spring Boot see my answer here

I have the following setup

  • Spring 4.3.8+
  • Hiberante 4.3.8+
  • Gradle 2.x
  • PostgreSQL 9.5

Some of the below configs are similar to some of the answers above but, there are differences.

Gradle stuff

In order to pull in the right jars, I needed to pull in the following jars

//latest driver because *brettw* see https://github.com/pgjdbc/pgjdbc/pull/849
compile 'org.postgresql:postgresql:42.2.0'
compile('com.zaxxer:HikariCP:2.7.6') {
    //they are pulled in separately elsewhere
    exclude group: 'org.hibernate', module: 'hibernate-core'
}

// Recommended to use HikariCPConnectionProvider by Hibernate in 4.3.6+    
compile('org.hibernate:hibernate-hikaricp:4.3.8.Final') {
        //they are pulled in separately elsewhere, to avoid version conflicts
        exclude group: 'org.hibernate', module: 'hibernate-core'
        exclude group: 'com.zaxxer', module: 'HikariCP'
}

// Needed for HikariCP logging if you use log4j
compile('org.slf4j:slf4j-simple:1.7.25')  
compile('org.slf4j:slf4j-log4j12:1.7.25') {
    //log4j pulled in separately, exclude to avoid version conflict
    exclude group: 'log4j', module: 'log4j'
}

Spring/Hibernate based configs

In order to get Spring & Hibernate to make use of Hikari Connection pool, you need to define the HikariDataSource and feed it into sessionFactory bean as shown below.

<!-- HikariCP Database bean -->
<bean id="dataSource" class="com.zaxxer.hikari.HikariDataSource" destroy-method="close">
    <constructor-arg ref="hikariConfig" />
</bean>

<!-- HikariConfig config that is fed to above dataSource -->
<bean id="hikariConfig" class="com.zaxxer.hikari.HikariConfig">
        <property name="poolName" value="SpringHikariPool" />
        <property name="dataSourceClassName" value="org.postgresql.ds.PGSimpleDataSource" />
        <property name="maximumPoolSize" value="20" />
        <property name="idleTimeout" value="30000" />

        <property name="dataSourceProperties">
            <props>
                <prop key="serverName">localhost</prop>
                <prop key="portNumber">5432</prop>
                <prop key="databaseName">dbname</prop>
                <prop key="user">dbuser</prop>
                <prop key="password">dbpassword</prop>
            </props>
        </property>
</bean>

<bean class="org.springframework.orm.hibernate4.LocalSessionFactoryBean" id="sessionFactory">
        <!-- Your Hikari dataSource below -->
        <property name="dataSource" ref="dataSource"/>
        <!-- your other configs go here -->
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.connection.provider_class">org.hibernate.hikaricp.internal.HikariCPConnectionProvider</prop>
                <!-- Remaining props goes here -->
            </props>
        </property>
 </bean>

Once the above are setup then, you need to add an entry to your log4j or logback and set the level to DEBUG to see Hikari Connection Pool start up.

Log4j1.2

<!-- Keep additivity=false to avoid duplicate lines -->
<logger additivity="false" name="com.zaxxer.hikari">
    <level value="debug"/>
    <!-- Your appenders goes here -->
</logger>

Logback

Via application.properties in Spring Boot

debug=true
logging.level.com.zaxxer.hikari.HikariConfig=DEBUG 

Using logback.xml

<logger name="com.zaxxer.hikari" level="DEBUG" additivity="false">
    <appender-ref ref="STDOUT" />
</logger>

With the above you should be all good to go! Obviously you need to customize the HikariCP pool configs in order to get the performance that it promises.

What are the rules for JavaScript's automatic semicolon insertion (ASI)?

The most contextual description of JavaScript's Automatic Semicolon Insertion I have found comes from a book about Crafting Interpreters.

JavaScript’s “automatic semicolon insertion” rule is the odd one. Where other languages assume most newlines are meaningful and only a few should be ignored in multi-line statements, JS assumes the opposite. It treats all of your newlines as meaningless whitespace unless it encounters a parse error. If it does, it goes back and tries turning the previous newline into a semicolon to get something grammatically valid.

He goes on to describe it as you would code smell.

This design note would turn into a design diatribe if I went into complete detail about how that even works, much less all the various ways that that is a bad idea. It’s a mess. JavaScript is the only language I know where many style guides demand explicit semicolons after every statement even though the language theoretically lets you elide them.

IE and Edge fix for object-fit: cover;

There is no rule to achieve that using CSS only, besides the object-fit (that you are currently using), which has partial support in EDGE1 so if you want to use this in IE, you have to use a object-fit polyfill in case you want to use just the element img, otherwise you have to do some workarounds.

You can see the the object-fit support here

UPDATE(2019)

You can use a simple JS snippet to detect if the object-fit is supported and then replace the img for a svg

_x000D_
_x000D_
//ES6 version
if ('objectFit' in document.documentElement.style === false) {
    document.addEventListener('DOMContentLoaded', () => {
        document.querySelectorAll('img[data-object-fit]').forEach(image => {
            (image.runtimeStyle || image.style).background = `url("${image.src}") no-repeat 50%/${image.currentStyle ? image.currentStyle['object-fit'] : image.getAttribute('data-object-fit')}`
            image.src = `data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='${image.width}' height='${image.height}'%3E%3C/svg%3E`
        })
    })
}

//ES5 version transpiled from code above with BabelJS
if ('objectFit' in document.documentElement.style === false) {
    document.addEventListener('DOMContentLoaded', function() {
        document.querySelectorAll('img[data-object-fit]').forEach(function(image) {
            (image.runtimeStyle || image.style).background = "url(\"".concat(image.src, "\") no-repeat 50%/").concat(image.currentStyle ? image.currentStyle['object-fit'] : image.getAttribute('data-object-fit'));
            image.src = "data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='".concat(image.width, "' height='").concat(image.height, "'%3E%3C/svg%3E");
        });
    });
}
_x000D_
img {
  display: inline-flex;
  width: 175px;
  height: 175px;
  margin-right: 10px;
  border: 1px solid red
}

[data-object-fit='cover'] {
  object-fit: cover
}

[data-object-fit='contain'] {
  object-fit: contain
}
_x000D_
<img data-object-fit='cover' src='//picsum.photos/1200/600' />
<img data-object-fit='contain' src='//picsum.photos/1200/600' />
<img src='//picsum.photos/1200/600' />
_x000D_
_x000D_
_x000D_

UPDATE(2018)

1 - EDGE has now partial support for object-fit since version 16, and by partial, it means only works in img element (future version 18 still has only partial support)

SS

Linq : select value in a datatable column

Thanks for your answers. I didn't understand what type of object "MyTable" was (in your answers) and the following code gave me the error shown below.

DataTable dt = ds.Tables[0];
var name = from r in dt
           where r.ID == 0
           select r.Name;

Could not find an implementation of the query pattern for source type 'System.Data.DataTable'. 'Where' not found

So I continued my googling and found something that does work:

var rowColl = ds.Tables[0].AsEnumerable();
string name = (from r in rowColl
              where r.Field<int>("ID") == 0
              select r.Field<string>("NAME")).First<string>();

What do you think?

Django Admin - change header 'Django administration' text

The easiest way of doing it make sure you have

from django.contrib import admin

and then just add these at bottom of url.py of you main application

admin.site.site_title = "Your App Title"
admin.site.site_header = "Your App Admin" 

WCF Error "This could be due to the fact that the server certificate is not configured properly with HTTP.SYS in the HTTPS case"

If you are using transfer mode = streamed, try changing it to buffered.

If this is not the problem could you post your configuration.

Function to clear the console in R and RStudio

If you are using the default R console, the key combination Option + Command + L will clear the console.

How to push both key and value into an Array in Jquery

There are no keys in JavaScript arrays. Use objects for that purpose.

var obj = {};

$.getJSON("displayjson.php",function (data) {
    $.each(data.news, function (i, news) {
        obj[news.title] = news.link;
    });                      
});

// later:
$.each(obj, function (index, value) {
    alert( index + ' : ' + value );
});

In JavaScript, objects fulfill the role of associative arrays. Be aware that objects do not have a defined "sort order" when iterating them (see below).

However, In your case it is not really clear to me why you transfer data from the original object (data.news) at all. Why do you not simply pass a reference to that object around?


You can combine objects and arrays to achieve predictable iteration and key/value behavior:

var arr = [];

$.getJSON("displayjson.php",function (data) {
    $.each(data.news, function (i, news) {
        arr.push({
            title: news.title, 
            link:  news.link
        });
    });                      
});

// later:
$.each(arr, function (index, value) {
    alert( value.title + ' : ' + value.link );
});

How to get current local date and time in Kotlin

I use this to fetch data from API every 20 seconds

 private fun isFetchNeeded(savedAt: Long): Boolean {
        return savedAt + 20000 < System.currentTimeMillis()
    }

Check file extension in upload form in PHP

pathinfo is cool but your code can be improved:

$filename = $_FILES['video_file']['name'];
$ext = pathinfo($filename, PATHINFO_EXTENSION);
$allowed = array('jpg','png','gif');
if( ! in_array( $ext, $allowed ) ) {echo 'error';}

Of course simply checking the extension of the filename would not guarantee the file type as a valid image. You may consider using a function like getimagesize to validate uploaded image files.

UITextField text change event

We can easily configure that from Storyboard, CTRL drag the @IBAction and change event as following:

enter image description here

SQL, How to convert VARCHAR to bigint?

I think your code is right. If you run the following code it converts the string '60' which is treated as varchar and it returns integer 60, if there is integer containing string in second it works.

select CONVERT(bigint,'60') as seconds 

and it returns

60

C# listView, how do I add items to columns 2, 3 and 4 etc?

There are several ways to do it, but here is one solution (for 4 columns).

string[] row1 = { "s1", "s2", "s3" };
listView1.Items.Add("Column1Text").SubItems.AddRange(row1);

And a more verbose way is here:

ListViewItem item1 = new ListViewItem("Something");
item1.SubItems.Add("SubItem1a");
item1.SubItems.Add("SubItem1b");
item1.SubItems.Add("SubItem1c");

ListViewItem item2 = new ListViewItem("Something2");
item2.SubItems.Add("SubItem2a");
item2.SubItems.Add("SubItem2b");
item2.SubItems.Add("SubItem2c");

ListViewItem item3 = new ListViewItem("Something3");
item3.SubItems.Add("SubItem3a");
item3.SubItems.Add("SubItem3b");
item3.SubItems.Add("SubItem3c");

ListView1.Items.AddRange(new ListViewItem[] {item1,item2,item3});

org.glassfish.jersey.servlet.ServletContainer ClassNotFoundException

The problem:

java.lang.ClassNotFoundException: org.glassfish.jersey.servlet.ServletContainer

indicates that you try to use the Jersey 2.x servlet, but you are supplying the Jersey 1.x libs.

For Jersey 1.x you have to do it like this:

<servlet>
  <servlet-name>Jersey REST Service</servlet-name>
<servlet-class>
  com.sun.jersey.spi.container.servlet.ServletContainer
</servlet-class>
  <init-param>
    <param-name>com.sun.jersey.config.property.packages</param-name>
    <param-value>sample.hello.resources</param-value>
  </init-param>
  <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
  <servlet-name>Jersey REST Service</servlet-name>
  <url-pattern>/rest/*</url-pattern>
</servlet-mapping>

For more information check the Jersey 1.x documentation.

If you instead want to use Jersey 2.x then you'll have to supply the Jersey 2.x libs. In a maven based project you can use the following:

<dependency>
    <groupId>org.glassfish.jersey.containers</groupId>
    <artifactId>jersey-container-servlet</artifactId>
    <version>2.xx</version>
</dependency>
<!-- if you are using Jersey client specific features without the server side -->
<dependency>
    <groupId>org.glassfish.jersey.core</groupId>
    <artifactId>jersey-client</artifactId>
    <version>2.xx</version>
</dependency>

For Jersey 2.x you don't need to setup anything in your web.xml, it is sufficient to supply a class similar to this:

import javax.ws.rs.ApplicationPath;
import javax.ws.rs.core.Application;

@ApplicationPath("rest")
public class ApplicationConfig extends Application {

}

For more information, check the Jersey documentation.

See also:

How to get "their" changes in the middle of conflicting Git rebase?

You want to use:

git checkout --ours foo/bar.java
git add foo/bar.java

If you rebase a branch feature_x against main (i.e. running git rebase main while on branch feature_x), during rebasing ours refers to main and theirs to feature_x.

As pointed out in the git-rebase docs:

Note that a rebase merge works by replaying each commit from the working branch on top of the branch. Because of this, when a merge conflict happens, the side reported as ours is the so-far rebased series, starting with <upstream>, and theirs is the working branch. In other words, the sides are swapped.

For further details read this thread.

Command-line Git on Windows

In the latest version (v2.19 for Windows when I'm writing), if you choose the option "Use git in Windows command prompt" (or sth similar, please read the options carefully when you install git), you should be able to use git commands in windows command prompt or windows powershell without any additional setting. Just remember to restart the command line tool after you install git.

How to run a command in the background and get no output?

Sorry this is a bit late but found the ideal solution for somple commands where you don't want any standard or error output (credit where it's due: http://felixmilea.com/2014/12/running-bash-commands-background-properly/)

This redirects output to null and keeps screen clear:

command &>/dev/null &

RecyclerView: Inconsistency detected. Invalid item position

This error occur when the list in adapter clear when user scrolling which make position of item holder changing, lost ref between list and item on ui, error happen in next "notifyDataSetChanged" request.

Fix:

Review your update list method. If you do something like

mainList.clear();
...
mainList.add() or mainList.addAll()
...
notifyDataSetChanged();

===> Error occur

How to fix. Create new list object for buffer processing and assign again to main list after that

List res = new ArrayList();
…..
res.add();  //add item or modify list
….
mainList = res;
notifyDataSetChanged();

Thanks to Nhan Cao for this great help :)

Calculating text width

I modified Nico's code to work for my needs.

$.fn.textWidth = function(){
    var self = $(this),
        children = self.contents(),
        calculator = $('<span style="white-space:nowrap;" />'),
        width;

    children.wrap(calculator);
    width = children.parent().width(); // parent = the calculator wrapper
    children.unwrap();
    return width;
};

I'm using .contents() as .children() does not return text nodes which I needed. I also found that the returned width was impacted by the viewport width which was causing wrapping so I'm using white-space:nowrap; to get the correct width regardless of viewport width.

The type java.util.Map$Entry cannot be resolved. It is indirectly referenced from required .class files

I've seen occasional problems with Eclipse forgetting that built-in classes (including Object and String) exist. The way I've resolved them is to:

  • On the Project menu, turn off "Build Automatically"
  • Quit and restart Eclipse
  • On the Project menu, choose "Clean…" and clean all projects
  • Turn "Build Automatically" back on and let it rebuild everything.

This seems to make Eclipse forget whatever incorrect cached information it had about the available classes.

Extracting .jar file with command line

jar xf myFile.jar
change myFile to name of your file
this will save the contents in the current folder of .jar file
that should do :)

How do I download a package from apt-get without installing it?

There are a least these apt-get extension packages that can help:

apt-offline - offline apt package manager
apt-zip - Update a non-networked computer using apt and removable media

This is specifically for the case of wanting to download where you have network access but to install on another machine where you do not.

Otherwise, the --download-only option to apt-get is your friend:

 -d, --download-only
     Download only; package files are only retrieved, not unpacked or installed.
     Configuration Item: APT::Get::Download-Only.

Changing cursor to waiting in javascript/jquery

jQuery:
$("body").css("cursor", "progress");

back again
$("body").css("cursor", "default");

Pure:
document.body.style.cursor = 'progress';

back again
document.body.style.cursor = 'default';

Why does python use 'else' after for and while loops?

I think documentation has a great explanation of else, continue

[...] it is executed when the loop terminates through exhaustion of the list (with for) or when the condition becomes false (with while), but not when the loop is terminated by a break statement."

Source: Python 2 docs: Tutorial on control flow

Sending credentials with cross-domain posts?

In jQuery 3 and perhaps earlier versions, the following simpler config also works for individual requests:

$.ajax(
        'https://foo.bar.com,
        {
            dataType: 'json',
            xhrFields: {
                withCredentials: true
            },
            success: successFunc
        }
    );

The full error I was getting in Firefox Dev Tools -> Network tab (in the Security tab for an individual request) was:

An error occurred during a connection to foo.bar.com.SSL peer was unable to negotiate an acceptable set of security parameters.Error code: SSL_ERROR_HANDSHAKE_FAILURE_ALERT

internet explorer 10 - how to apply grayscale filter?

Use this jQuery plugin https://gianlucaguarini.github.io/jQuery.BlackAndWhite/

That seems to be the only one cross-browser solution. Plus it has a nice fade in and fade out effect.

$('.bwWrapper').BlackAndWhite({
    hoverEffect : true, // default true
    // set the path to BnWWorker.js for a superfast implementation
    webworkerPath : false,
    // to invert the hover effect
    invertHoverEffect: false,
    // this option works only on the modern browsers ( on IE lower than 9 it remains always 1)
    intensity:1,
    speed: { //this property could also be just speed: value for both fadeIn and fadeOut
        fadeIn: 200, // 200ms for fadeIn animations
        fadeOut: 800 // 800ms for fadeOut animations
    },
    onImageReady:function(img) {
        // this callback gets executed anytime an image is converted
    }
});

Normalize columns of pandas data frame

Based on this post: https://stats.stackexchange.com/questions/70801/how-to-normalize-data-to-0-1-range

You can do the following:

def normalize(df):
    result = df.copy()
    for feature_name in df.columns:
        max_value = df[feature_name].max()
        min_value = df[feature_name].min()
        result[feature_name] = (df[feature_name] - min_value) / (max_value - min_value)
    return result

You don't need to stay worrying about whether your values are negative or positive. And the values should be nicely spread out between 0 and 1.

How to create radio buttons and checkbox in swift (iOS)?

  1. Create 2 buttons one as "YES" and another as "NO".
  2. Create a BOOL property Ex: isNRICitizen = false
  3. Give same button connection to both the buttons and set a tag (Ex: Yes button - tag 10 and No button -tag 20)
@IBAction func btnAction(_ sender:UIButton) {

isNRICitizen = sender.tag == 10 ? true : false
isNRICitizen ? self.nriCitizenBtnYes.setImage(#imageLiteral(resourceName: "radioChecked"), for: .normal) : self.nriCitizenBtnYes.setImage(#imageLiteral(resourceName: "radioUnchecked"), for: .normal)
        isNRICitizen ? self.nriCitizenBtnNo.setImage(#imageLiteral(resourceName: "radioUnchecked"), for: .normal) : self.nriCitizenBtnNo.setImage(#imageLiteral(resourceName: "radioChecked"), for: .normal)
}

Get the index of a certain value in an array in PHP

The problem is that you don't have a numerical index on your array.
Using array_values() will create a zero indexed array that you can then search using array_search() bypassing the need to use a for loop.

$list = ['string1', 'string2', 'string3'];
$index = array_search('string2',array_values($list));

Replace text in HTML page with jQuery

Check out Padolsey's article on DOM find and replace, as well as the library to implement the described algorithm.

In this sample usage, I replace all text inside a <div id="content"> that looks like a US telephone number with a tel: scheme link:

findAndReplaceDOMText(document.getElementById('content'), {
    find:/\b(\d\d\d-\d\d\d-\d\d\d\d)\b/g,
    replace:function (portion) {
        var a = document.createElement('a');
        a.className = 'telephone';
        a.href = 'tel:' + portion.text.replace(/\D/g, '');
        a.textContent = portion.text;
        return a;
    }
});

How to style the option of an html "select" element?

You can use inline styles to add custome styling to <option> tags.

For eg : <option style="font-weight:bold;color:#09C;">Option 1</option> This will apply the styles to this particular <option> element only.

Then you can use a bit of javascript magic to apply the inline styles to all of the <option> elements within a <select> tag like so :

var select = $(document).getElementById('#select-element-id')

var option = select.children('#option-element-id')

option.css('font-weight', 'bold')

option.css('font-size', '24px')

You can also use <option value="" disabled> <br> </option> to add a line-break between the options.

Redirecting 404 error with .htaccess via 301 for SEO etc

I came up with the solution and posted it on my blog

http://web.archive.org/web/20130310123646/http://onlinemarketingexperts.com.au/2013/01/how-to-permanently-redirect-301-all-404-missing-pages-in-htaccess/

here is the htaccess code also

RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule . / [L,R=301]

but I posted other solutions on my blog too, it depends what you need really

'NoneType' object is not subscriptable?

list1 = ["name1", "info1", 10]
list2 = ["name2", "info2", 30]
list3 = ["name3", "info3", 50]

def printer(*lists):
    for _list in lists:
        for ele in _list:
            print(ele, end = ", ")
        print()

printer(list1, list2, list3)

Append Char To String in C?

C does not have strings per se -- what you have is a char pointer pointing to some read-only memory containing the characters "blablabla\0". In order to append a character there, you need a) writable memory and b) enough space for the string in its new form. The string literal "blablabla\0" has neither.

The solutions are:

1) Use malloc() et al. to dynamically allocate memory. (Don't forget to free() afterwards.)
2) Use a char array.

When working with strings, consider using strn* variants of the str* functions -- they will help you stay within memory bounds.

Sanitizing user input before adding it to the DOM in Javascript

You could use a simple regular expression to assert that the id only contains allowed characters, like so:

if(id.match(/^[0-9a-zA-Z]{1,16}$/)){
    //The id is fine
}
else{
    //The id is illegal
}

My example allows only alphanumerical characters, and strings of length 1 to 16, you should change it to match the type of ids that you use.

By the way, at line 6, the value property is missing a pair of quotes, an easy mistake to make when you quote on two levels.

I can't see your actual data flow, depending on context this check may not at all be needed, or it may not be enough. In order to make a proper security review we would need more information.

In general, about built in escape or sanitize functions, don't trust them blindly. You need to know exactly what they do, and you need to establish that that is actually what you need. If it is not what you need, the code your own, most of the time a simple whitelisting regex like the one I gave you works just fine.

Check if XML Element exists

//if the problem is "just" to verify that the element exist in the xml-file before you //extract the value you could do like this

XmlNodeList YOURTEMPVARIABLE = doc.GetElementsByTagName("YOUR_ELEMENTNAME");

        if (YOURTEMPVARIABLE.Count > 0 )
        {
            doctype = YOURTEMPVARIABLE[0].InnerXml;

        }
        else
        {
            doctype = "";
        }

How do I format {{$timestamp}} as MM/DD/YYYY in Postman?

My solution is similar to Payam's, except I am using

//older code
//postman.setGlobalVariable("currentDate", new Date().toLocaleDateString());
pm.globals.set("currentDate", new Date().toLocaleDateString());

If you hit the "3 dots" on the folder and click "Edit"

enter image description here

Then set Pre-Request Scripts for the all calls, so the global variable is always available.

enter image description here

Common elements in two lists

public static <T> List<T> getCommonElements(
            java.util.Collection<T> a,
            java.util.Collection<T> b
            ) {
        if(a==null && b==null) return new ArrayList<>();
        if(a!=null && a.size()==0) return new ArrayList<>(b);           
        if(b!=null && b.size()==0) return new ArrayList<>(a);
        
        Set<T> set= a instanceof HashSet?(HashSet<T>)a:new HashSet<>(a);
        return b.stream().filter(set::contains).collect(Collectors.toList());
    }

For better time performance, please use HashSet (O(1) look up) instead of List(O(n) look ups)

Time complexity- O(b) Space Complexity- O(a)

Get the Application Context In Fragment In Android?

You can get the context using getActivity().getApplicationContext();

Remove a JSON attribute

The selected answer would work for as long as you know the key itself that you want to delete but if it should be truly dynamic you would need to use the [] notation instead of the dot notation.

For example:

var keyToDelete = "key1";
var myObj = {"test": {"key1": "value", "key2": "value"}}

//that will not work.
delete myObj.test.keyToDelete 

instead you would need to use:

delete myObj.test[keyToDelete];

Substitute the dot notation with [] notation for those values that you want evaluated before being deleted.

Struct like objects in Java

It appears that many Java people are not familiar with the Sun Java Coding Guidelines which say it is quite appropriate to use public instance variable when the class is essentially a "Struct", if Java supported "struct" (when there is no behavior).

People tend to think getters and setters are the Java way, as if they are at the heart of Java. This is not so. If you follow the Sun Java Coding Guidelines, using public instance variables in appropriate situations, you are actually writing better code than cluttering it with needless getters and setters.

Java Code Conventions from 1999 and still unchanged.

10.1 Providing Access to Instance and Class Variables

Don't make any instance or class variable public without good reason. Often, instance variables don't need to be explicitly set or gotten-often that happens as a side effect of method calls.

One example of appropriate public instance variables is the case where the class is essentially a data structure, with no behavior. In other words, if you would have used a struct instead of a class (if Java supported struct), then it's appropriate to make the class's instance variables public.

http://www.oracle.com/technetwork/java/javase/documentation/codeconventions-137265.html#177

http://en.wikipedia.org/wiki/Plain_old_data_structure

http://docs.oracle.com/javase/1.3/docs/guide/collections/designfaq.html#28