Programs & Examples On #Html.radiobuttonlist

How can I escape a single quote?

use javascript inbuild functions escape and unescape

for example

var escapedData = escape("hel'lo");   
output = "%27hel%27lo%27" which can be used in the attribute.

again to read the value from the attr

var unescapedData = unescape("%27hel%27lo%27")
output = "'hel'lo'"

This will be helpful if you have huge json stringify data to be used in the attribute

g++ undefined reference to typeinfo

The previous answers are correct, but this error can also be caused by attempting to use typeid on an object of a class that has no virtual functions. C++ RTTI requires a vtable, so classes that you wish to perform type identification on require at least one virtual function.

If you want type information to work on a class for which you don't really want any virtual functions, make the destructor virtual.

Get cart item name, quantity all details woocommerce

Try this :

<?php
    global $woocommerce;
    $items = $woocommerce->cart->get_cart();

        foreach($items as $item => $values) { 
            $_product =  wc_get_product( $values['data']->get_id()); 
            echo "<b>".$_product->get_title().'</b>  <br> Quantity: '.$values['quantity'].'<br>'; 
            $price = get_post_meta($values['product_id'] , '_price', true);
            echo "  Price: ".$price."<br>";
        } 
?>

To get Product Image and Regular & Sale Price:

<?php
    global $woocommerce;
    $items = $woocommerce->cart->get_cart();

        foreach($items as $item => $values) { 
            $_product =  wc_get_product( $values['data']->get_id() );
            //product image
            $getProductDetail = wc_get_product( $values['product_id'] );
            echo $getProductDetail->get_image(); // accepts 2 arguments ( size, attr )

            echo "<b>".$_product->get_title() .'</b>  <br> Quantity: '.$values['quantity'].'<br>'; 
            $price = get_post_meta($values['product_id'] , '_price', true);
            echo "  Price: ".$price."<br>";
            /*Regular Price and Sale Price*/
            echo "Regular Price: ".get_post_meta($values['product_id'] , '_regular_price', true)."<br>";
            echo "Sale Price: ".get_post_meta($values['product_id'] , '_sale_price', true)."<br>";
        }
?>

Does java have a int.tryparse that doesn't throw an exception for bad data?

No. You have to make your own like this:

boolean tryParseInt(String value) {  
     try {  
         Integer.parseInt(value);  
         return true;  
      } catch (NumberFormatException e) {  
         return false;  
      }  
}

...and you can use it like this:

if (tryParseInt(input)) {  
   Integer.parseInt(input);  // We now know that it's safe to parse
}

EDIT (Based on the comment by @Erk)

Something like follows should be better

public int tryParse(String value, int defaultVal) {
    try {
        return Integer.parseInt(value);
    } catch (NumberFormatException e) {
        return defaultVal;
    }
}

When you overload this with a single string parameter method, it would be even better, which will enable using with the default value being optional.

public int tryParse(String value) {
    return tryParse(value, 0)
}

Make Error 127 when running trying to compile code

Error 127 means one of two things:

  1. file not found: the path you're using is incorrect. double check that the program is actually in your $PATH, or in this case, the relative path is correct -- remember that the current working directory for a random terminal might not be the same for the IDE you're using. it might be better to just use an absolute path instead.
  2. ldso is not found: you're using a pre-compiled binary and it wants an interpreter that isn't on your system. maybe you're using an x86_64 (64-bit) distro, but the prebuilt is for x86 (32-bit). you can determine whether this is the answer by opening a terminal and attempting to execute it directly. or by running file -L on /bin/sh (to get your default/native format) and on the compiler itself (to see what format it is).

if the problem is (2), then you can solve it in a few diff ways:

  1. get a better binary. talk to the vendor that gave you the toolchain and ask them for one that doesn't suck.
  2. see if your distro can install the multilib set of files. most x86_64 64-bit distros allow you to install x86 32-bit libraries in parallel.
  3. build your own cross-compiler using something like crosstool-ng.
  4. you could switch between an x86_64 & x86 install, but that seems a bit drastic ;).

Parsing JSON object in PHP using json_decode

If you use the following instead:

$json = file_get_contents($url);
$data = json_decode($json, TRUE);

The TRUE returns an array instead of an object.

How to find the size of a table in SQL?

And in PostgreSQL:

SELECT pg_size_pretty(pg_relation_size('tablename'));

Check if an element is present in an array

ECMAScript 2016 incorporates an includes() method for arrays that specifically solves the problem, and so is now the preferred method.

[1, 2, 3].includes(2);     // true
[1, 2, 3].includes(4);     // false
[1, 2, 3].includes(1, 2);  // false (second parameter is the index position in this array at which to begin searching)

As of JULY 2018, this has been implemented in almost all major browsers, if you need to support an older browser a polyfill is available.

Edit: Note that this returns false if the item in the array is an object. This is because similar objects are two different objects in JavaScript.

How to execute powershell commands from a batch file?

This is what the code would look like in a batch file(tested, works):

powershell -Command "& {set-location 'HKCU:\Software\Microsoft\Windows\CurrentVersion\Internet Settings'; set-location ZoneMap\Domains; new-item SERVERNAME; set-location SERVERNAME; new-itemproperty . -Name http -Value 2 -Type DWORD;}"

Based on the information from:

http://dmitrysotnikov.wordpress.com/2008/06/27/powershell-script-in-a-bat-file/

How to sort an ArrayList in Java

Use a Comparator like this:

List<Fruit> fruits= new ArrayList<Fruit>();

Fruit fruit;
for(int i = 0; i < 100; i++)
{
  fruit = new Fruit();
  fruit.setname(...);
  fruits.add(fruit);
}

// Sorting
Collections.sort(fruits, new Comparator<Fruit>() {
        @Override
        public int compare(Fruit fruit2, Fruit fruit1)
        {

            return  fruit1.fruitName.compareTo(fruit2.fruitName);
        }
    });

Now your fruits list is sorted based on fruitName.

Maven project.build.directory

Aside from @Verhás István answer (which I like), I was expecting a one-liner for the question:

${project.reporting.outputDirectory} resolves to target/site in your project.

Intellij reformat on file save

I wound up rebinding the Reformat code... action to Ctrl-S, replacing the default binding for Save All.

It may sound crazy at first, but IntelliJ seems to save on virtually every action: running tests, building the project, even when closing an editor tab. I have a habit of hitting Ctrl-S pretty often, so this actually works quite well for me. It's certainly easier to type than the default bind for reformatting.

relative path to CSS file

You have to move the css folder into your web folder. It seems that your web folder on the hard drive equals the /ServletApp folder as seen from the www. Other content than inside your web folder cannot be accessed from the browsers.

The url of the CSS link is then

 <link rel="stylesheet" type="text/css" href="/ServletApp/css/styles.css"/>

Handling the TAB character in Java

You can also use the tab character '\t' to represent a tab, instead of "\t".

char c ='t';
char c =(char)9;

Git Pull vs Git Rebase

git pull and git rebase are not interchangeable, but they are closely connected.

git pull fetches the latest changes of the current branch from a remote and applies those changes to your local copy of the branch. Generally this is done by merging, i.e. the local changes are merged into the remote changes. So git pull is similar to git fetch & git merge.

Rebasing is an alternative to merging. Instead of creating a new commit that combines the two branches, it moves the commits of one of the branches on top of the other.

You can pull using rebase instead of merge (git pull --rebase). The local changes you made will be rebased on top of the remote changes, instead of being merged with the remote changes.

Atlassian has some excellent documentation on merging vs. rebasing.

Join a list of items with different types as string in Python

How come no-one seems to like repr?
python 3.7.2:

>>> int_list = [1, 2, 3, 4, 5]
>>> print(repr(int_list))
[1, 2, 3, 4, 5]
>>> 

Take care though, it's an explicit representation. An example shows:

#Print repr(object) backwards
>>> print(repr(int_list)[::-1])
]5 ,4 ,3 ,2 ,1[
>>> 

more info at pydocs-repr

Makefile - missing separator

You need to precede the lines starting with gcc and rm with a hard tab. Commands in make rules are required to start with a tab (unless they follow a semicolon on the same line). The result should look like this:

PROG = semsearch
all: $(PROG)
%: %.c
        gcc -o $@ $< -lpthread

clean:
        rm $(PROG)

Note that some editors may be configured to insert a sequence of spaces instead of a hard tab. If there are spaces at the start of these lines you'll also see the "missing separator" error. If you do have problems inserting hard tabs, use the semicolon way:

PROG = semsearch
all: $(PROG)
%: %.c ; gcc -o $@ $< -lpthread

clean: ; rm $(PROG)

How to disable gradle 'offline mode' in android studio?

Offline mode could be set in Android Studio and in your project. To verify that gradle won't build your project in offline mode:

  1. Disable gradle offline mode in Android Studio gradle settings.
  2. Verify that your project's gradle.settings won't contain: startParameter.offline=true

How to give a pandas/matplotlib bar graph custom colors

For a more detailed answer on creating your own colormaps, I highly suggest visiting this page

If that answer is too much work, you can quickly make your own list of colors and pass them to the color parameter. All the colormaps are in the cm matplotlib module. Let's get a list of 30 RGB (plus alpha) color values from the reversed inferno colormap. To do so, first get the colormap and then pass it a sequence of values between 0 and 1. Here, we use np.linspace to create 30 equally-spaced values between .4 and .8 that represent that portion of the colormap.

from matplotlib import cm
color = cm.inferno_r(np.linspace(.4, .8, 30))
color

array([[ 0.865006,  0.316822,  0.226055,  1.      ],
       [ 0.851384,  0.30226 ,  0.239636,  1.      ],
       [ 0.832299,  0.283913,  0.257383,  1.      ],
       [ 0.817341,  0.270954,  0.27039 ,  1.      ],
       [ 0.796607,  0.254728,  0.287264,  1.      ],
       [ 0.775059,  0.239667,  0.303526,  1.      ],
       [ 0.758422,  0.229097,  0.315266,  1.      ],
       [ 0.735683,  0.215906,  0.330245,  1.      ],
       .....

Then we can use this to plot, using the data from the original post:

import random
x = [{i: random.randint(1, 5)} for i in range(30)]
df = pd.DataFrame(x)
df.plot(kind='bar', stacked=True, color=color, legend=False, figsize=(12, 4))

enter image description here

groovy.lang.MissingPropertyException: No such property: jenkins for class: groovy.lang.Binding

As pointed out by @Jayan in another post, the solution was to do the following

import jenkins.model.*
jenkins = Jenkins.instance

Then I was able to do the rest of my scripting the way it was.

Difference between h:button and h:commandButton

This is taken from the book - The Complete Reference by Ed Burns & Chris Schalk

h:commandButton vs h:button

What’s the difference between h:commandButton|h:commandLink and h:button|h:link ?

The latter two components were introduced in 2.0 to enable bookmarkable JSF pages, when used in concert with the View Parameters feature.

There are 3 main differences between h:button|h:link and h:commandButton|h:commandLink.

First, h:button|h:link causes the browser to issue an HTTP GET request, while h:commandButton|h:commandLink does a form POST. This means that any components in the page that have values entered by the user, such as text fields, checkboxes, etc., will not automatically be submitted to the server when using h:button|h:link. To cause values to be submitted with h:button|h:link, extra action has to be taken, using the “View Parameters” feature.

The second main difference between the two kinds of components is that h:button|h:link has an outcome attribute to describe where to go next while h:commandButton|h:commandLink uses an action attribute for this purpose. This is because the former does not result in an ActionEvent in the event system, while the latter does.

Finally, and most important to the complete understanding of this feature, the h:button|h:link components cause the navigation system to be asked to derive the outcome during the rendering of the page, and the answer to this question is encoded in the markup of the page. In contrast, the h:commandButton|h:commandLink components cause the navigation system to be asked to derive the outcome on the POSTBACK from the page. This is a difference in timing. Rendering always happens before POSTBACK.

How to transform currentTimeMillis to a readable date format?

It will work.

long yourmilliseconds = System.currentTimeMillis();
SimpleDateFormat sdf = new SimpleDateFormat("MMM dd,yyyy HH:mm");    
Date resultdate = new Date(yourmilliseconds);
System.out.println(sdf.format(resultdate));

Get the Query Executed in Laravel 3/4

Here is a quick Javascript snippet you can throw onto your master page template. As long as it's included, all queries will be output to your browser's Javascript Console. It prints them in an easily readable list, making it simple to browse around your site and see what queries are executing on each page.

When you're done debugging, just remove it from your template.

<script type="text/javascript">
    var queries = {{ json_encode(DB::getQueryLog()) }};
    console.log('/****************************** Database Queries ******************************/');
    console.log(' ');
    queries.forEach(function(query) {
        console.log('   ' + query.time + ' | ' + query.query + ' | ' + query.bindings[0]);
    });
    console.log(' ');
    console.log('/****************************** End Queries ***********************************/');
</script>

How do you create nested dict in Python?

UPDATE: For an arbitrary length of a nested dictionary, go to this answer.

Use the defaultdict function from the collections.

High performance: "if key not in dict" is very expensive when the data set is large.

Low maintenance: make the code more readable and can be easily extended.

from collections import defaultdict

target_dict = defaultdict(dict)
target_dict[key1][key2] = val

Crystal Reports for VS2012 - VS2013 - VS2015 - VS2017 - VS2019

There is also someone who managed to modify CR for VS.NET 2010 to install on 2012, using MS ORCA in this thread: http://scn.sap.com/thread/3235515 . I couldn't get it to work myself, though.

Check if string contains \n Java

For portability, you really should do something like this:

public static final String NEW_LINE = System.getProperty("line.separator")
.
.
.
word.contains(NEW_LINE);

unless you're absolutely certain that "\n" is what you want.

Sort ArrayList of custom Objects by property

Well if you using Java 8 or older version Here is the Best solution.

Collections.sort(studentList, Comparator.comparing(Student::getCgpa).reversed().thenComparing(Student:: getFname).thenComparing(Student::getId));

In this case, it will first sort with 'getCgpa' first and for the second part it will sort with getFname and getId. Which is field into the pojo class.

How to select an item from a dropdown list using Selenium WebDriver with java?

Tagname you should mentioned like that "option", if text with space we can use this method it should work.

WebElement select = driver.findElement(By.id("gender"));
List<WebElement> options = select.findElements(By.tagName("option"));

for (WebElement option : options) {

if("Germany".equals(option.getText().trim()))

 option.click();   
}

What is the result of % in Python?

In most languages % is used for modulus. Python is no exception.

Set up a scheduled job?

Simple way is to write a custom shell command see Django Documentation and execute it using a cronjob on linux. However i would highly recommend using a message broker like RabbitMQ coupled with celery. Maybe you can have a look at this Tutorial

Remove all special characters from a string in R?

Instead of using regex to remove those "crazy" characters, just convert them to ASCII, which will remove accents, but will keep the letters.

astr <- "Ábcdêãçoàúü"
iconv(astr, from = 'UTF-8', to = 'ASCII//TRANSLIT')

which results in

[1] "Abcdeacoauu"

How do I start a process from C#?

Just as Matt says, use Process.Start.

You can pass a URL, or a document. They will be started by the registered application.

Example:

Process.Start("Test.Txt");

This will start Notepad.exe with Text.Txt loaded.

How to set a variable inside a loop for /F

Simple example of batch code using %var%, !var!, and %%.

In this example code, focus here is that we want to capture a start time using the built in variable TIME (using time because it always changes automatically):

Code:

@echo off
setlocal enabledelayedexpansion
SET "SERVICES_LIST=MMS ARSM MMS2"
SET START=%TIME%
SET "LAST_SERVICE="

for %%A in (%SERVICES_LIST%) do (
    SET START=!TIME!
    CALL :SOME_FUNCTION %%A
    SET "LAST_SERVICE=%%A"
    ping -n 5 127.0.0.1 > NUL
    SET OTHER=!START!
    if !OTHER! EQU !START! (
    echo !OTHER! is equal to !START! as expected
    ) ELSE (
    echo NOTHING
    )
)
ECHO Last service run was %LAST_SERVICE%

:: Function declared like this
:SOME_FUNCTION
echo Running: %1
EXIT /B 0

Comments on code:

  • Use enabledelayedexpansion
  • The first three SET lines are typical uses of the SET command, use this most of the time.
  • The next line is a for loop, must use %%A for iteration, then %%B if a loop inside it etc.. You can not use long variable names.
  • To access a changed variable such as the time variable, you must use !! or set with !! (have enableddelayexpansion enabled).
  • When looping in for loop each iteration is accessed as the %%A variable.
  • The code in the for loop is point out the various ways to set a variable. Looking at 'SET OTHER=!START!', if you were to change to SET OTHER=%START% you will see why !! is needed. (hint: you will see NOTHING) output.
  • In short !! is more likely needed inside of loops, %var% in general, %% always a for loop.

Further reading

Use the following links to determine why in more detail:

Find and replace with a newline in Visual Studio Code

In version 1.1.1:

  • Ctrl+H
  • Check the regular exp icon .*
  • Search: ><
  • Replace: >\n<

What’s the best way to get an HTTP response code from a URL?

The urllib2.HTTPError exception does not contain a getcode() method. Use the code attribute instead.

Toggle visibility property of div

It's better if you check visibility like this: if($('#video-over').is(':visible'))

How to find the php.ini file used by the command line?

Run php --ini in your terminal, you'll get all details about ini files

[root@tamilan src]# php --ini
Configuration File (php.ini) Path: /etc
Loaded Configuration File:         /etc/php.ini
Scan for additional .ini files in: /etc/php.d
Additional .ini files parsed:      /etc/php.d/apc.ini,
/etc/php.d/bcmath.ini,
/etc/php.d/curl.ini,
/etc/php.d/dba.ini,
/etc/php.d/dom.ini,
/etc/php.d/fileinfo.ini,
/etc/php.d/gd.ini,
/etc/php.d/imap.ini,
/etc/php.d/json.ini,
/etc/php.d/mbstring.ini,
/etc/php.d/memcache.ini,
/etc/php.d/mysql.ini,
/etc/php.d/mysqli.ini,
/etc/php.d/pdo.ini,
/etc/php.d/pdo_mysql.ini,
/etc/php.d/pdo_sqlite.ini,
/etc/php.d/phar.ini,
/etc/php.d/posix.ini,
/etc/php.d/sqlite3.ini,
/etc/php.d/ssh2.ini,
/etc/php.d/sysvmsg.ini,
/etc/php.d/sysvsem.ini,
/etc/php.d/sysvshm.ini,
/etc/php.d/wddx.ini,
/etc/php.d/xmlreader.ini,
/etc/php.d/xmlwriter.ini,
/etc/php.d/xsl.ini,
/etc/php.d/zip.ini

For more, use helping command php --help It'll display all the possible options.

Python find elements in one list that are not in the other

If you want a one-liner solution (ignoring imports) that only requires O(max(n, m)) work for inputs of length n and m, not O(n * m) work, you can do so with the itertools module:

from itertools import filterfalse

main_list = list(filterfalse(set(list_1).__contains__, list_2))

This takes advantage of the functional functions taking a callback function on construction, allowing it to create the callback once and reuse it for every element without needing to store it somewhere (because filterfalse stores it internally); list comprehensions and generator expressions can do this, but it's ugly.†

That gets the same results in a single line as:

main_list = [x for x in list_2 if x not in list_1]

with the speed of:

set_1 = set(list_1)
main_list = [x for x in list_2 if x not in set_1]

Of course, if the comparisons are intended to be positional, so:

list_1 = [1, 2, 3]
list_2 = [2, 3, 4]

should produce:

main_list = [2, 3, 4]

(because no value in list_2 has a match at the same index in list_1), you should definitely go with Patrick's answer, which involves no temporary lists or sets (even with sets being roughly O(1), they have a higher "constant" factor per check than simple equality checks) and involves O(min(n, m)) work, less than any other answer, and if your problem is position sensitive, is the only correct solution when matching elements appear at mismatched offsets.

†: The way to do the same thing with a list comprehension as a one-liner would be to abuse nested looping to create and cache value(s) in the "outermost" loop, e.g.:

main_list = [x for set_1 in (set(list_1),) for x in list_2 if x not in set_1]

which also gives a minor performance benefit on Python 3 (because now set_1 is locally scoped in the comprehension code, rather than looked up from nested scope for each check; on Python 2 that doesn't matter, because Python 2 doesn't use closures for list comprehensions; they operate in the same scope they're used in).

How to set up a PostgreSQL database in Django

Please note that installation of psycopg2 via pip or setup.py requires to have Visual Studio 2008 (more precisely executable file vcvarsall.bat). If you don't have admin rights to install it or set the appropriate PATH variable on Windows, you can download already compiled library from here.

System.Data.SqlClient.SqlException: Invalid object name 'dbo.Projects'

I had the same error. The cause was that I had created a table with wrong schema(it ought to be [dbo]). I did the following steps:

  1. I dropped all tables which does not have a prefix "dbo."

  2. I created and run this query:

CREATE TABLE dbo.Cars(IDCar int PRIMARY KEY NOT NULL,Name varchar(25) NOT NULL,    
CarDescription text NULL)
GO

Confirmation before closing of tab/browser

I read comments on answer set as Okay. Most of the user are asking that the button and some links click should be allowed. Here one more line is added to the existing code that will work.

<script type="text/javascript">
  var hook = true;
  window.onbeforeunload = function() {
    if (hook) {

      return "Did you save your stuff?"
    }
  }
  function unhook() {
    hook=false;
  }

Call unhook() onClick for button and links which you want to allow. E.g.

<a href="#" onClick="unhook()">This link will allow navigation</a>

'cannot open git-upload-pack' error in Eclipse when cloning or pushing git repository

One cause of this is having Fiddler2 configured to decrypt HTTPS traffic. Close Fiddler2 and it should work fine.

How to align an image dead center with bootstrap

You could change the CSS of the previous solution as below:

.container, .row { text-align: center; }

This should center all the elements in the parent div as well.

How to watch for array changes?

From reading all the answers here, I have assembled a simplified solution that does not require any external libraries.

It also illustrates much better the general idea for the approach:

function processQ() {
   // ... this will be called on each .push
}

var myEventsQ = [];
myEventsQ.push = function() { Array.prototype.push.apply(this, arguments);  processQ();};

Check whether values in one data frame column exist in a second data frame

Use %in% as follows

A$C %in% B$C

Which will tell you which values of column C of A are in B.

What is returned is a logical vector. In the specific case of your example, you get:

A$C %in% B$C
# [1]  TRUE FALSE  TRUE  TRUE

Which you can use as an index to the rows of A or as an index to A$C to get the actual values:

# as a row index
A[A$C %in% B$C,  ]  # note the comma to indicate we are indexing rows

# as an index to A$C
A$C[A$C %in% B$C]
[1] 1 3 4  # returns all values of A$C that are in B$C

We can negate it too:

A$C[!A$C %in% B$C]
[1] 2   # returns all values of A$C that are NOT in B$C



If you want to know if a specific value is in B$C, use the same function:

  2 %in% B$C   # "is the value 2 in B$C ?"  
  # FALSE

  A$C[2] %in% B$C  # "is the 2nd element of A$C in B$C ?"  
  # FALSE

Convert an enum to List<string>

Use Enum's static method, GetNames. It returns a string[], like so:

Enum.GetNames(typeof(DataSourceTypes))

If you want to create a method that does only this for only one type of enum, and also converts that array to a List, you can write something like this:

public List<string> GetDataSourceTypes()
{
    return Enum.GetNames(typeof(DataSourceTypes)).ToList();
}

You will need Using System.Linq; at the top of your class to use .ToList()

Java Regex Capturing Groups

Your understanding is correct. However, if we walk through:

  • (.*) will swallow the whole string;
  • it will need to give back characters so that (\\d+) is satistifed (which is why 0 is captured, and not 3000);
  • the last (.*) will then capture the rest.

I am not sure what the original intent of the author was, however.

Why won't eclipse switch the compiler to Java 8?

I had the same problem even though I had:

  • a freshly downloaded JDK 1.8.0

  • JAVA_HOME is set

  • java -version on command line reports 1.8

  • Java in control panel is set to 1.8

  • downloaded Eclipse Mars

Eclipse only let me choose a compiler compliance level op to 1.7 in the compiler preferences, even though my installed JRE is 1.8.0. I also couldn't see a 1.8 in the Execution Environments underneath Installed JREs, only a JavaSE-1.7 (which I haven't even got installed!). When I clicked on that, it shows "jdk1.8.0" as a compatible JRE, so I selected that, but still no change.

Then I unzipped Eclipse Mars into a brand new directory, created a new project, and now I can select 1.8, hurrah! That greatly reduced the "Duplicate methods named spliterator..." errors I was getting when compiling my code under Java 1.8, however, there is still one left:

Duplicate default methods named spliterator with the parameters () and () are inherited from the types List and Set.

However, that's likely because I'm extending AbstractList and implementing Set, so I've fixed that for now by removing the implements Set because it doesn't really add anything in my case (other than signifying that my collection has only unique elements)

Ant build failed: "Target "build..xml" does not exist"

since your ant file's name is build.xml, you should just type ant without ant build.xml. that is: > ant [enter]

Copying files into the application folder at compile time

You could do this with a post build event. Set the files to no action on compile, then in the macro copy the files to the directory you want.

Here's a post build Macro that I think will work by copying all files in a directory called Configuration to the root build folder:

copy $(ProjectDir)Configuration\* $(ProjectDir)$(OutDir)

Clear and reset form input fields

Using event.target.reset() only works for uncontrolled components, which is not recommended. For controlled components you would do something like this:

import React, { Component } from 'react'

class MyForm extends Component {
  initialState = { name: '' }

  state = this.initialState

  handleFormReset = () => {
    this.setState(() => this.initialState)
  }

  render() {

    return (
      <form onReset={this.handleFormReset}>
        <div>
          <label htmlFor="name">Name</label>
          <input
            type="text"
            placeholder="Enter name"
            name="name"
            value={name}
            onChange={this.handleInputOnChange}
          />
        </div>
        <div>
          <input
            type="submit"
            value="Submit"
          />
          <input
            type="reset"
            value="Reset"
          />
        </div>
      </form>
    )
  }
}

ContactAdd.propTypes = {}

export default MyForm

Get first 100 characters from string, respecting full words

The problem with accepted answer is that result string goes over the the limit, i.e. it can exceed 100 chars since strpos will look after the offset and so your length will always be a over your limit. If the last word is long, like squirreled then the length of your result will be 111 (to give you an idea).

A better solution is to use wordwrap function:

function truncate($str, $length = 125, $append = '...') {
    if (strlen($str) > $length) {
        $delim = "~\n~";
        $str = substr($str, 0, strpos(wordwrap($str, $length, $delim), $delim)) . $append;
    } 

    return $str;
}


echo truncate("The quick brown fox jumped over the lazy dog.", 5);

This way you can be sure the string is truncated under your limit (and never goes over)

P.S. This is particularly useful if you plan to store the truncated string in your database with a fixed-with column like VARCHAR(50), etc.

P.P.S. Note the special delimiter in wordwrap. This is to make sure that your string is truncated correctly even when it contains newlines (otherwise it will truncate at first newline which you don't want).

Get client IP address via third party web service

    $.ajax({
        url: '//freegeoip.net/json/',
        type: 'POST',
        dataType: 'jsonp',
        success: function(location) {
            alert(location.ip);
        }
    });

This will work https too

How to split large text file in windows?

Of course there is! Win CMD can do a lot more than just split text files :)

Split a text file into separate files of 'max' lines each:

Split text file (max lines each):
: Initialize
set input=file.txt
set max=10000

set /a line=1 >nul
set /a file=1 >nul
set out=!file!_%input%
set /a max+=1 >nul

echo Number of lines in %input%:
find /c /v "" < %input%

: Split file
for /f "tokens=* delims=[" %i in ('type "%input%" ^| find /v /n ""') do (

if !line!==%max% (
set /a line=1 >nul
set /a file+=1 >nul
set out=!file!_%input%
echo Writing file: !out!
)

REM Write next file
set a=%i
set a=!a:*]=]!
echo:!a:~1!>>out!
set /a line+=1 >nul
)

If above code hangs or crashes, this example code splits files faster (by writing data to intermediate files instead of keeping everything in memory):

eg. To split a file with 7,600 lines into smaller files of maximum 3000 lines.

  1. Generate regexp string/pattern files with set command to be fed to /g flag of findstr

list1.txt

\[[0-9]\]
\[[0-9][0-9]\]
\[[0-9][0-9][0-9]\]
\[[0-2][0-9][0-9][0-9]\]

list2.txt

\[[3-5][0-9][0-9][0-9]\]

list3.txt

\[[6-9][0-9][0-9][0-9]\]

  1. Split the file into smaller files:
type "%input%" | find /v /n "" | findstr /b /r /g:list1.txt > file1.txt
type "%input%" | find /v /n "" | findstr /b /r /g:list2.txt > file2.txt
type "%input%" | find /v /n "" | findstr /b /r /g:list3.txt > file3.txt
  1. remove prefixed line numbers for each file split:
    eg. for the 1st file:
for /f "tokens=* delims=[" %i in ('type "%cd%\file1.txt"') do (
set a=%i
set a=!a:*]=]!
echo:!a:~1!>>file_1.txt)

Notes:
Works with leading whitespace, blank lines & whitespace lines.

Tested on Win 10 x64 CMD, on 4.4GB text file, 5651982 lines.

Getting first value from map in C++

A map will not keep insertion order. Use *(myMap.begin()) to get the value of the first pair (the one with the smallest key when ordered).

You could also do myMap.begin()->first to get the key and myMap.begin()->second to get the value.

What are callee and caller saved registers?

Caller-saved registers (AKA volatile registers, or call-clobbered) are used to hold temporary quantities that need not be preserved across calls.

For that reason, it is the caller's responsibility to push these registers onto the stack or copy them somewhere else if it wants to restore this value after a procedure call.

It's normal to let a call destroy temporary values in these registers, though.

Callee-saved registers (AKA non-volatile registers, or call-preserved) are used to hold long-lived values that should be preserved across calls.

When the caller makes a procedure call, it can expect that those registers will hold the same value after the callee returns, making it the responsibility of the callee to save them and restore them before returning to the caller. Or to not touch them.

How to Run Terminal as Administrator on Mac Pro

To switch to root so that all subsequent commands are executed with high privileges instead of using sudo before each command use following command and then provide the password when prompted.

sudo -i

User will change and remain root until you close the terminal. Execute exit commmand which will change the user back to original user without closing terminal.

How can I reconcile detached HEAD with master/origin?

Get your detached commit onto its own branch

Simply run git checkout -b mynewbranch.

Then run git log, and you'll see that commit is now HEAD on this new branch.

How to convert an ArrayList containing Integers to primitive int array?

If you're using Eclipse Collections, you can use the collectInt() method to switch from an object container to a primitive int container.

List<Integer> integers = new ArrayList<>(Arrays.asList(1, 2, 3, 4, 5));
MutableIntList intList =
  ListAdapter.adapt(integers).collectInt(i -> i);
Assert.assertArrayEquals(new int[]{1, 2, 3, 4, 5}, intList.toArray());

If you can convert your ArrayList to a FastList, you can get rid of the adapter.

Assert.assertArrayEquals(
  new int[]{1, 2, 3, 4, 5},
  Lists.mutable.with(1, 2, 3, 4, 5)
    .collectInt(i -> i).toArray());

Note: I am a committer for Eclipse collections.

How to compile without warnings being treated as errors?

Sure, find where -Werror is set and remove that flag. Then warnings will be only warnings.

java.lang.ClassNotFoundException: org.apache.xmlbeans.XmlObject Error

I was working with talend V7.3.1 and I had poi version "4.1.0" and including xml-beans from the list of dependencies didnt fix my problem (i.e: 2.3.0 and 2.6.0).

It was fixed by downloading the jar "xmlbeans-3.0.1.jar" and adding it to the project

enter image description here

How to update (append to) an href in jquery?

$("a.directions-link").attr("href", $("a.directions-link").attr("href")+"...your additions...");

Catch multiple exceptions in one line (except block)

How do I catch multiple exceptions in one line (except block)

Do this:

try:
    may_raise_specific_errors():
except (SpecificErrorOne, SpecificErrorTwo) as error:
    handle(error) # might log or have some other default behavior...

The parentheses are required due to older syntax that used the commas to assign the error object to a name. The as keyword is used for the assignment. You can use any name for the error object, I prefer error personally.

Best Practice

To do this in a manner currently and forward compatible with Python, you need to separate the Exceptions with commas and wrap them with parentheses to differentiate from earlier syntax that assigned the exception instance to a variable name by following the Exception type to be caught with a comma.

Here's an example of simple usage:

import sys

try:
    mainstuff()
except (KeyboardInterrupt, EOFError): # the parens are necessary
    sys.exit(0)

I'm specifying only these exceptions to avoid hiding bugs, which if I encounter I expect the full stack trace from.

This is documented here: https://docs.python.org/tutorial/errors.html

You can assign the exception to a variable, (e is common, but you might prefer a more verbose variable if you have long exception handling or your IDE only highlights selections larger than that, as mine does.) The instance has an args attribute. Here is an example:

import sys

try:
    mainstuff()
except (KeyboardInterrupt, EOFError) as err: 
    print(err)
    print(err.args)
    sys.exit(0)

Note that in Python 3, the err object falls out of scope when the except block is concluded.

Deprecated

You may see code that assigns the error with a comma. This usage, the only form available in Python 2.5 and earlier, is deprecated, and if you wish your code to be forward compatible in Python 3, you should update the syntax to use the new form:

import sys

try:
    mainstuff()
except (KeyboardInterrupt, EOFError), err: # don't do this in Python 2.6+
    print err
    print err.args
    sys.exit(0)

If you see the comma name assignment in your codebase, and you're using Python 2.5 or higher, switch to the new way of doing it so your code remains compatible when you upgrade.

The suppress context manager

The accepted answer is really 4 lines of code, minimum:

try:
    do_something()
except (IDontLikeYouException, YouAreBeingMeanException) as e:
    pass

The try, except, pass lines can be handled in a single line with the suppress context manager, available in Python 3.4:

from contextlib import suppress

with suppress(IDontLikeYouException, YouAreBeingMeanException):
     do_something()

So when you want to pass on certain exceptions, use suppress.

ng-model for `<input type="file"/>` (with directive DEMO)

This is a slightly modified version that lets you specify the name of the attribute in the scope, just as you would do with ng-model, usage:

    <myUpload key="file"></myUpload>

Directive:

.directive('myUpload', function() {
    return {
        link: function postLink(scope, element, attrs) {
            element.find("input").bind("change", function(changeEvent) {                        
                var reader = new FileReader();
                reader.onload = function(loadEvent) {
                    scope.$apply(function() {
                        scope[attrs.key] = loadEvent.target.result;                                
                    });
                }
                if (typeof(changeEvent.target.files[0]) === 'object') {
                    reader.readAsDataURL(changeEvent.target.files[0]);
                };
            });

        },
        controller: 'FileUploadCtrl',
        template:
                '<span class="btn btn-success fileinput-button">' +
                '<i class="glyphicon glyphicon-plus"></i>' +
                '<span>Replace Image</span>' +
                '<input type="file" accept="image/*" name="files[]" multiple="">' +
                '</span>',
        restrict: 'E'

    };
});

What datatype to use when storing latitude and longitude data in SQL databases?

I think it depends on the operations you'll be needing to do most frequently.

If you need the full value as a decimal number, then use decimal with appropriate precision and scale. Float is way beyond your needs, I believe.

If you'll be converting to/from degºmin'sec"fraction notation often, I'd consider storing each value as an integer type (smallint, tinyint, tinyint, smallint?).

get one item from an array of name,value JSON

Arrays are normally accessed via numeric indexes, so in your example arr[0] == {name:"k1", value:"abc"}. If you know that the name property of each object will be unique you can store them in an object instead of an array, as follows:

var obj = {};
obj["k1"] = "abc";
obj["k2"] = "hi";
obj["k3"] = "oa";

alert(obj["k2"]); // displays "hi"

If you actually want an array of objects like in your post you can loop through the array and return when you find an element with an object having the property you want:

function findElement(arr, propName, propValue) {
  for (var i=0; i < arr.length; i++)
    if (arr[i][propName] == propValue)
      return arr[i];

  // will return undefined if not found; you could return a default instead
}

// Using the array from the question
var x = findElement(arr, "name", "k2"); // x is {"name":"k2", "value":"hi"}
alert(x["value"]); // displays "hi"

var y = findElement(arr, "name", "k9"); // y is undefined
alert(y["value"]); // error because y is undefined

alert(findElement(arr, "name", "k2")["value"]); // displays "hi";

alert(findElement(arr, "name", "zzz")["value"]); // gives an error because the function returned undefined which won't have a "value" property

What is a callback function?

Callback Function A function which passed to another function as an argument.

function test_function(){       
 alert("Hello world");  
} 

setTimeout(test_function, 2000);

Note: In above example test_function used as an argument for setTimeout function.

How to count no of lines in text file and store the value into a variable using batch script?

There is a much simpler way than all of these other methods.

find /v /c "" filename.ext

Holdover from the legacy MS-DOS days, apparently. More info here: https://devblogs.microsoft.com/oldnewthing/20110825-00/?p=9803

Example use:

adb shell pm list packages | find /v /c ""

If your android device is connected to your PC and you have the android SDK on your path, this prints out the number of apps installed on your device.

MySQL ERROR 1045 (28000): Access denied for user 'bill'@'localhost' (using password: YES)

OS: windows

My error message is:

MySQL ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)

My reason is that I didn't open cmd with administrator permissions.

So my solution was to open cmd as administrator, then it worked.

MySQL - Get row number on select

Take a look at this.

Change your query to:

SET @rank=0;
SELECT @rank:=@rank+1 AS rank, itemID, COUNT(*) as ordercount
  FROM orders
  GROUP BY itemID
  ORDER BY ordercount DESC;
SELECT @rank;

The last select is your count.

Get a json via Http Request in NodeJS

Just setting json option to true, the body will contain the parsed json:

request({
  url: 'http://...',
  json: true
}, function(error, response, body) {
  console.log(body);
});

How to plot a function curve in R

Here is a lattice version:

library(lattice)
eq<-function(x) {x*x}
X<-1:1000
xyplot(eq(X)~X,type="l")

Lattice output

How can I see an the output of my C programs using Dev-C++?

; It works...

#include <iostream>
using namespace std;
int main ()
{
   int x,y; // (Or whatever variable you want you can)

your required process syntax type here then;

   cout << result 

(or your required output result statement); use without space in getchar and other syntax.

   getchar();
}

Now you can save your file with .cpp extension and use ctrl + f 9 to compile and then use ctrl + f 10 to execute the program. It will show you the output window and it will not vanish with a second Until you click enter to close the output window.

How to move/rename a file using an Ansible task on a remote system

- name: Move the src file to dest
  command: mv /path/to/src /path/to/dest
  args:
    removes: /path/to/src
    creates: /path/to/dest

This runs the mv command only when /path/to/src exists and /path/to/dest does not, so it runs once per host, moves the file, then doesn't run again.

I use this method when I need to move a file or directory on several hundred hosts, many of which may be powered off at any given time. It's idempotent and safe to leave in a playbook.

Why do I need to explicitly push a new branch?

You don't, see below

I find this 'feature' rather annoying since I'm not trying to launch rockets to the moon, just push my damn branch. You probably do too or else you wouldn't be here!

Here is the fix: if you want it to implicitly push for the current branch regardless of if that branch exists on origin just issue this command once and you will never have to again anywhere:

git config --global push.default current

So if you make branches like this:

git checkout -b my-new-branch

and then make some commits and then do a

git push -u

to get them out to origin (being on that branch) and it will create said branch for you if it doesn't exist.

Note the -u bit makes sure they are linked if you were to pull later on from said branch. If you have no plans to pull the branch later (or are okay with another one liner if you do) -u is not necessary.

Server did not recognize the value of HTTP Header SOAPAction

We had renamed some of our webservice project namespaces and forgot to update the website httphandlers config section with the namespace of the renamed projects.

set environment variable in python script

You can add elements to your environment by using

os.environ['LD_LIBRARY_PATH'] = 'my_path'

and run subprocesses in a shell (that uses your os.environ) by using

subprocess.call('sqsub -np ' + var1 + '/homedir/anotherdir/executable', shell=True)

How to detect if a browser is Chrome using jQuery?

var is_chrome = /chrome/.test( navigator.userAgent.toLowerCase() );

How do I validate a date string format in python?

>>> import datetime
>>> def validate(date_text):
    try:
        datetime.datetime.strptime(date_text, '%Y-%m-%d')
    except ValueError:
        raise ValueError("Incorrect data format, should be YYYY-MM-DD")


>>> validate('2003-12-23')
>>> validate('2003-12-32')

Traceback (most recent call last):
  File "<pyshell#20>", line 1, in <module>
    validate('2003-12-32')
  File "<pyshell#18>", line 5, in validate
    raise ValueError("Incorrect data format, should be YYYY-MM-DD")
ValueError: Incorrect data format, should be YYYY-MM-DD

Python 2: AttributeError: 'list' object has no attribute 'strip'

You can first concatenate the strings in the list with the separator ';' using the function join and then use the split function in order create the list:

l = ['Facebook;Google+;MySpace', 'Apple;Android']

l1 = ";".join(l)).split(";")  

print l1

outputs

['Facebook', 'Google+', 'MySpace', 'Apple', 'Android']

'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?

The short-circuiting boolean operators (and, or) can't be overriden because there is no satisfying way to do this without introducing new language features or sacrificing short circuiting. As you may or may not know, they evaluate the first operand for its truth value, and depending on that value, either evaluate and return the second argument, or don't evaluate the second argument and return the first:

something_true and x -> x
something_false and x -> something_false
something_true or x -> something_true
something_false or x -> x

Note that the (result of evaluating the) actual operand is returned, not truth value thereof.

The only way to customize their behavior is to override __nonzero__ (renamed to __bool__ in Python 3), so you can affect which operand gets returned, but not return something different. Lists (and other collections) are defined to be "truthy" when they contain anything at all, and "falsey" when they are empty.

NumPy arrays reject that notion: For the use cases they aim at, two different notions of truth are common: (1) Whether any element is true, and (2) whether all elements are true. Since these two are completely (and silently) incompatible, and neither is clearly more correct or more common, NumPy refuses to guess and requires you to explicitly use .any() or .all().

& and | (and not, by the way) can be fully overriden, as they don't short circuit. They can return anything at all when overriden, and NumPy makes good use of that to do element-wise operations, as they do with practically any other scalar operation. Lists, on the other hand, don't broadcast operations across their elements. Just as mylist1 - mylist2 doesn't mean anything and mylist1 + mylist2 means something completely different, there is no & operator for lists.

How to print React component on click of a button?

There is kind of two solutions on the client. One is with frames like you posted. You can use an iframe though:

var content = document.getElementById("divcontents");
var pri = document.getElementById("ifmcontentstoprint").contentWindow;
pri.document.open();
pri.document.write(content.innerHTML);
pri.document.close();
pri.focus();
pri.print();

This expects this html to exist

<iframe id="ifmcontentstoprint" style="height: 0px; width: 0px; position: absolute"></iframe>

The other solution is to use the media selector and on the media="print" styles hide everything you don't want to print.

<style type="text/css" media="print">
   .no-print { display: none; }
</style>

Last way requires some work on the server. You can send all the HTML+CSS to the server and use one of many components to generate a printable document like PDF. I've tried setups doing this with PhantomJs.

File is universal (three slices), but it does not contain a(n) ARMv7-s slice error for static libraries on iOS, anyway to bypass?

use menu Project -> Build Settings ->

then remove armv7s from the"valid architectures". If standard has been chosen then delete that and then add armv7.

How to print number with commas as thousands separators?

Italy:

>>> import locale
>>> locale.setlocale(locale.LC_ALL,"")
'Italian_Italy.1252'
>>> f"{1000:n}"
'1.000'

How to select all checkboxes with jQuery?

Simple and clean:

_x000D_
_x000D_
$('#select_all').click(function() {_x000D_
  var c = this.checked;_x000D_
  $(':checkbox').prop('checked', c);_x000D_
});
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
<form>_x000D_
  <table>_x000D_
    <tr>_x000D_
      <td><input type="checkbox" id="select_all" /></td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <td><input type="checkbox" name="select[]" /></td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <td><input type="checkbox" name="select[]" /></td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <td><input type="checkbox" name="select[]" /></td>_x000D_
    </tr>_x000D_
  </table>_x000D_
</form>
_x000D_
_x000D_
_x000D_

JavaScript displaying a float to 2 decimal places

number.parseFloat(2) works but it returns a string.

If you'd like to preserve it as a number type you can use:

Math.round(number * 100) / 100

How do you set the EditText keyboard to only consist of numbers on Android?

In xml edittext:

android:id="@+id/text"

In program:

EditText text=(EditText) findViewById(R.id.text);
text.setRawInputType(Configuration.KEYBOARDHIDDEN_YES);

How can I access my localhost from my Android device?

use connectify and xampp or equivalent, and type ip address on mobile URL bar to access

Running shell command and capturing the output

eg, execute('ls -ahl') differentiated three/four possible returns and OS platforms:

  1. no output, but run successfully
  2. output empty line, run successfully
  3. run failed
  4. output something, run successfully

function below

def execute(cmd, output=True, DEBUG_MODE=False):
"""Executes a bash command.
(cmd, output=True)
output: whether print shell output to screen, only affects screen display, does not affect returned values
return: ...regardless of output=True/False...
        returns shell output as a list with each elment is a line of string (whitespace stripped both sides) from output
        could be 
        [], ie, len()=0 --> no output;    
        [''] --> output empty line;     
        None --> error occured, see below

        if error ocurs, returns None (ie, is None), print out the error message to screen
"""
if not DEBUG_MODE:
    print "Command: " + cmd

    # https://stackoverflow.com/a/40139101/2292993
    def _execute_cmd(cmd):
        if os.name == 'nt' or platform.system() == 'Windows':
            # set stdin, out, err all to PIPE to get results (other than None) after run the Popen() instance
            p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True)
        else:
            # Use bash; the default is sh
            p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True, executable="/bin/bash")

        # the Popen() instance starts running once instantiated (??)
        # additionally, communicate(), or poll() and wait process to terminate
        # communicate() accepts optional input as stdin to the pipe (requires setting stdin=subprocess.PIPE above), return out, err as tuple
        # if communicate(), the results are buffered in memory

        # Read stdout from subprocess until the buffer is empty !
        # if error occurs, the stdout is '', which means the below loop is essentially skipped
        # A prefix of 'b' or 'B' is ignored in Python 2; 
        # it indicates that the literal should become a bytes literal in Python 3 
        # (e.g. when code is automatically converted with 2to3).
        # return iter(p.stdout.readline, b'')
        for line in iter(p.stdout.readline, b''):
            # # Windows has \r\n, Unix has \n, Old mac has \r
            # if line not in ['','\n','\r','\r\n']: # Don't print blank lines
                yield line
        while p.poll() is None:                                                                                                                                        
            sleep(.1) #Don't waste CPU-cycles
        # Empty STDERR buffer
        err = p.stderr.read()
        if p.returncode != 0:
            # responsible for logging STDERR 
            print("Error: " + str(err))
            yield None

    out = []
    for line in _execute_cmd(cmd):
        # error did not occur earlier
        if line is not None:
            # trailing comma to avoid a newline (by print itself) being printed
            if output: print line,
            out.append(line.strip())
        else:
            # error occured earlier
            out = None
    return out
else:
    print "Simulation! The command is " + cmd
    print ""

What is the difference between fastcgi and fpm?

Running PHP as a CGI means that you basically tell your web server the location of the PHP executable file, and the server runs that executable

whereas

PHP FastCGI Process Manager (PHP-FPM) is an alternative FastCGI daemon for PHP that allows a website to handle strenuous loads. PHP-FPM maintains pools (workers that can respond to PHP requests) to accomplish this. PHP-FPM is faster than traditional CGI-based methods, such as SUPHP, for multi-user PHP environments

However, there are pros and cons to both and one should choose as per their specific use case.

I found info on this link for fastcgi vs fpm quite helpful in choosing which handler to use in my scenario.

How to count down in for loop?

In python, when you have an iterable, usually you iterate without an index:

letters = 'abcdef' # or a list, tupple or other iterable
for l in letters:
    print(l)

If you need to traverse the iterable in reverse order, you would do:

for l in letters[::-1]:
    print(l)

When for any reason you need the index, you can use enumerate:

for i, l in enumerate(letters, start=1): #start is 0 by default
    print(i,l)

You can enumerate in reverse order too...

for i, l in enumerate(letters[::-1])
    print(i,l)

ON ANOTHER NOTE...

Usually when we traverse an iterable we do it to apply the same procedure or function to each element. In these cases, it is better to use map:

If we need to capitilize each letter:

map(str.upper, letters)

Or get the Unicode code of each letter:

map(ord, letters)

CSS/Javascript to force html table row on a single line

Try:

td, th {
  white-space: nowrap;
  overflow: hidden;
}

Differences between MySQL and SQL Server

Lots of comments here sound more like religious arguments than real life statements. I've worked for years with both MySQL and MSSQL and both are good products. I would choose MySQL mainly based on the environment that you are working on. Most open source projects use MySQL, so if you go into that direction MySQL is your choice. If you develop something with .Net I would choose MSSQL, not because it's much better, but just cause that is what most people use. I'm actually currently on a Project that uses ASP.NET with MySQL and C#. It works perfectly fine.

Copy multiple files from one directory to another from Linux shell

Use wildcards:

cp /home/ankur/folder/* /home/ankur/dest

If you don't want to copy all the files, you can use braces to select files:

cp /home/ankur/folder/{file{1,2},xyz,abc} /home/ankur/dest

This will copy file1, file2, xyz, and abc.

You should read the sections of the bash man page on Brace Expansion and Pathname Expansion for all the ways you can simplify this.

Another thing you can do is cd /home/ankur/folder. Then you can type just the filenames rather than the full pathnames, and you can use filename completion by typing Tab.

Use 'import module' or 'from module import'?

I was answering a similar question post but the poster deleted it before i could post. Here is one example to illustrate the differences.

Python libraries may have one or more files (modules). For exmaples,

package1
  |-- __init__.py

or

package2
  |-- __init__.py
  |-- module1.py
  |-- module2.py

We can define python functions or classes inside any of the files based design requirements.

Let's define

  1. func1() in __init__.py under mylibrary1, and
  2. foo() in module2.py under mylibrary2.

We can access func1() using one of these methods

import package1

package1.func1()

or

import package1 as my

my.func1()

or

from package1 import func1

func1()

or

from package1 import *

func1()

We can use one of these methods to access foo():

import package2.module2

package2.module2.foo()

or

import package2.module2 as mod2

mod2.foo()

or

from package2 import module2

module2.foo()

or

from package2 import module2 as mod2

mod2.foo()

or

from package2.module2 import *

foo()

Generics in C#, using type of a variable as parameter

You can't use it in the way you describe. The point about generic types, is that although you may not know them at "coding time", the compiler needs to be able to resolve them at compile time. Why? Because under the hood, the compiler will go away and create a new type (sometimes called a closed generic type) for each different usage of the "open" generic type.

In other words, after compilation,

DoesEntityExist<int>

is a different type to

DoesEntityExist<string>

This is how the compiler is able to enfore compile-time type safety.

For the scenario you describe, you should pass the type as an argument that can be examined at run time.

The other option, as mentioned in other answers, is that of using reflection to create the closed type from the open type, although this is probably recommended in anything other than extreme niche scenarios I'd say.

Windows 7 environment variable not working in path

Things like having %PATH% or spaces between items in your path will break it. Be warned.

Yes, windows paths that include spaces will cause errors. For example an application added this to the front of the system %PATH% variable definition:

C:\Program Files (x86)\WebEx\Productivity Tools;C:\Sybase\IQ-16_0\Bin64;

which caused all of the paths in %PATH% to not be set in the cmd window.

My solution is to demarcate the extended path variable in double quotes where needed:

"C:\Program Files (x86)\WebEx\Productivity Tools";C:\Sybase\IQ-16_0\Bin64;

The spaces are therefore ignored and the full path variable is parsed properly.

How to get URL parameters with Javascript?

function getURLParameter(name) {
  return decodeURIComponent((new RegExp('[?|&]' + name + '=' + '([^&;]+?)(&|#|;|$)').exec(location.search) || [null, ''])[1].replace(/\+/g, '%20')) || null;
}

So you can use:

myvar = getURLParameter('myvar');

HTTP Ajax Request via HTTPS Page

Still, this can be done with the following steps:

  1. send an https ajax request to your web-site (the same domain)

    jQuery.ajax({
        'url'      : '//same_domain.com/ajax_receiver.php',
        'type'     : 'get',
        'data'     : {'foo' : 'bar'},
        'success'  : function(response) {
            console.log('Successful request');
        }
    }).fail(function(xhr, err) {
        console.error('Request error');
    });
    
  2. get ajax request, for example, by php, and make a CURL get request to any desired website via http.

    use linslin\yii2\curl;
    $curl = new curl\Curl();
    $curl->get('http://example.com');
    

How to fix "no valid 'aps-environment' entitlement string found for application" in Xcode 4.3?

Ok, I faced the problem before. Since push notification requires serverside implementation, for me recreating profile was not an option. So I found this solution WITHOUT creating new provisioning profile.

Xcode is not properly selecting the correct provisioning profile although we are selecting it correctly.

First go to organizer. On the Devices tab, Provisioning profile from Library list, select the intended profile we are trying to use. Right click on it and then "Reveal Profile in Finder".

enter image description here

The correct profile will be selected in the opened Finder window. Note the name.

enter image description here

Now go to Xcode > Log Navigator. Select filter for "All" and "All Messages". Now in the last phase(Build Target) look for the step called "ProcessProductPackaging" expand it. Note the provisioning profile name. They should NOT match if you are having the error. enter image description here

Now in the Opened Finder window delete the rogue provisioning profile which Xcode is using. Now build again. The error should be resolved. If not repeat the process to find another rogue profile to remove it.

Hope this helps.

Increasing Google Chrome's max-connections-per-server limit to more than 6

I don't know that you can do it in Chrome outside of Windows -- some Googling shows that Chrome (and therefore possibly Chromium) might respond well to a certain registry hack.

However, if you're just looking for a simple solution without modifying your code base, have you considered Firefox? In the about:config you can search for "network.http.max" and there are a few values in there that are definitely worth looking at.

Also, for a device that will not be moving (i.e. it is mounted in a fixed location) you should consider not using Wi-Fi (even a Home-Plug would be a step up as far as latency / stability / dropped connections go).

How to horizontally center an element

Instead of multiple wrappers and/or auto margins, this simple solution works for me:

<div style="top: 50%; left: 50%;
    height: 100px; width: 100px;
    margin-top: -50px; margin-left: -50px;
    background: url('lib/loading.gif') no-repeat center #fff;
    text-align: center;
    position: fixed; z-index: 9002;">Loading...</div>

It puts the div at the center of the view (vertical and horizontal), sizes and adjusts for size, centers background image (vertical and horizontal), centers text (horizontal), and keeps div in the view and on top of the content. Simply place in the HTML body and enjoy.

how to delete all commit history in github?

Deleting the .git folder may cause problems in your git repository. If you want to delete all your commit history but keep the code in its current state, it is very safe to do it as in the following:

  1. Checkout

    git checkout --orphan latest_branch

  2. Add all the files

    git add -A

  3. Commit the changes

    git commit -am "commit message"

  4. Delete the branch

    git branch -D main

  5. Rename the current branch to main

    git branch -m main

  6. Finally, force update your repository

    git push -f origin main

PS: this will not keep your old commit history around

Concatenation of strings in Lua

Strings can be joined together using the concatenation operator ".."

this is the same for variables I think

How can I find the method that called the current method?

We can also use lambda's in order to find the caller.

Suppose you have a method defined by you:

public void MethodA()
    {
        /*
         * Method code here
         */
    }

and you want to find it's caller.

1. Change the method signature so we have a parameter of type Action (Func will also work):

public void MethodA(Action helperAction)
        {
            /*
             * Method code here
             */
        }

2. Lambda names are not generated randomly. The rule seems to be: > <CallerMethodName>__X where CallerMethodName is replaced by the previous function and X is an index.

private MethodInfo GetCallingMethodInfo(string funcName)
    {
        return GetType().GetMethod(
              funcName.Substring(1,
                                funcName.IndexOf("&gt;", 1, StringComparison.Ordinal) - 1)
              );
    }

3. When we call MethodA the Action/Func parameter has to be generated by the caller method. Example:

MethodA(() => {});

4. Inside MethodA we can now call the helper function defined above and find the MethodInfo of the caller method.

Example:

MethodInfo callingMethodInfo = GetCallingMethodInfo(serverCall.Method.Name);

How to connect to local instance of SQL Server 2008 Express

Start your Local SQL Server Service

  • Start SQL Config Manager: Click Start -> Microsoft SQL Server 2008 R2 -> SQL Server Configuration Manager
  • Start SQL Services: Set the SQL Server (SQLEXPRESS) and SQL Server Browser services to automatic start mode. Right-click each service -> Properties -> Go into the Service Tab

This will ensure they start up again if you restart your computer. Please check to ensure the state is "Running" for both services.

Starting up your Local SQL Server 2008 Service

Login and authenticate with your Local SQL Server

  • Now open up SQL Server Management Studio and click "Connect to Object Explorer" and select Server Name:

[Your PC name]\SQLEXPRESS

Example: 8540P-KL\SQLEXPRESS or (localhost)\SQLEXPRESS

  • To find your PC name: Right click My Computer -> Properties -> Computer Name tab

  • Alternative: Login using windows authentication: Using the user name [Your Domain]/[Your User Name]

SQL Server 2008 User Account Settings

Setup User Account

  • Create a new Login acct: In SQL Mgmt Studio -> Expand your local Server -> Security -> Right click on Logins -> New Login

  • Set Password settings on New User Account: Uncheck Enforce password policy, password expiration and user must change pw(Since this is local) Default database -> Your Database

  • Grant roles to New User Account: User Mapping Page -> Map to your db and grant db_owner role Status Page -> Grant Permission to connect and Enable Login

SQL Server 2008 User Settings Local DB

Setup Access Permissions/Settings for User

  • Enable all auth modes: Right click your Local Server -> Properties -> Security Tab -> Enable SQL Server and Windows Authentication Mode
  • Enable TCP/IP: Open SQL Server Configuration Manager -> SQL Server Network Configuration -> Protocols for SQLEXPRESS -> Enable TCP/IP
  • Restart SQL Server Service: You will have to restart the SQL Server(SQLEXPRESS) after enabling TCP/IP

SQL Server 2008 Server Permissions

Database Properties File for Spring Project

  • database.url=jdbc:jtds:sqlserver://[local PC Computer
    name];instance=SQLEXPRESS;DatabaseName=[db name];

  • database.username=[Your user name] database.password=[Your password]

  • database.driverClassName=net.sourceforge.jtds.jdbc.Driver

If you want to view larger screen shots and better formatting of the answer with more details please view the blog article below: Setting up a Local Instance of SQL Server 2008 Blog Post:

Alert handling in Selenium WebDriver (selenium 2) with Java

Write the following method:

public boolean isAlertPresent() {
    try {
        driver.switchTo().alert();
        return true;
    } // try
    catch (Exception e) {
        return false;
    } // catch
}

Now, you can check whether alert is present or not by using the method written above as below:

if (isAlertPresent()) {
    driver.switchTo().alert();
    driver.switchTo().alert().accept();
    driver.switchTo().defaultContent();
}

Determine if JavaScript value is an "integer"?

Try this:

if(Math.floor(id) == id && $.isNumeric(id)) 
  alert('yes its an int!');

$.isNumeric(id) checks whether it's numeric or not
Math.floor(id) == id will then determine if it's really in integer value and not a float. If it's a float parsing it to int will give a different result than the original value. If it's int both will be the same.

Multiple Indexes vs Multi-Column Indexes

I agree with Cade Roux.

This article should get you on the right track:

One thing to note, clustered indexes should have a unique key (an identity column I would recommend) as the first column. Basically it helps your data insert at the end of the index and not cause lots of disk IO and Page splits.

Secondly, if you are creating other indexes on your data and they are constructed cleverly they will be reused.

e.g. imagine you search a table on three columns

state, county, zip.

  • you sometimes search by state only.
  • you sometimes search by state and county.
  • you frequently search by state, county, zip.

Then an index with state, county, zip. will be used in all three of these searches.

If you search by zip alone quite a lot then the above index will not be used (by SQL Server anyway) as zip is the third part of that index and the query optimiser will not see that index as helpful.

You could then create an index on Zip alone that would be used in this instance.

By the way We can take advantage of the fact that with Multi-Column indexing the first index column is always usable for searching and when you search only by 'state' it is efficient but yet not as efficient as Single-Column index on 'state'

I guess the answer you are looking for is that it depends on your where clauses of your frequently used queries and also your group by's.

The article will help a lot. :-)

make iframe height dynamic based on content inside- JQUERY/Javascript

you could also add a repeating requestAnimationFrame to your resizeIframe (e.g. from @BlueFish's answer) which would always be called before the browser paints the layout and you could update the height of the iframe when its content have changed their heights. e.g. input forms, lazy loaded content etc.

<script type="text/javascript">
  function resizeIframe(iframe) {
    iframe.height = iframe.contentWindow.document.body.scrollHeight + "px";
    window.requestAnimationFrame(() => resizeIframe(iframe));
  }
</script>  

<iframe onload="resizeIframe(this)" ...

your callback should be fast enough to have no big impact on your overall performance

How can I draw vertical text with CSS cross-browser?

My solution that would work on Chrome, Firefox, IE9, IE10 (Change the degrees as per your requirement):

.rotate-text {
  -webkit-transform: rotate(270deg);
  -moz-transform: rotate(270deg);
  -ms-transform: rotate(270deg);
  -o-transform: rotate(270deg);
  transform: rotate(270deg);
  filter: none; /*Mandatory for IE9 to show the vertical text correctly*/      
}

Get Last Part of URL PHP

If you are looking for a robust version that can deal with any form of URLs, this should do nicely:

<?php

$url = "http://foobar.com/foo/bar/1?baz=qux#fragment/foo";
$lastSegment = basename(parse_url($url, PHP_URL_PATH));

3-dimensional array in numpy

No need to go in such deep technicalities, and get yourself blasted. Let me explain it in the most easiest way. We all have studied "Sets" during our school-age in Mathematics. Just consider 3D numpy array as the formation of "sets".

x = np.zeros((2,3,4)) 

Simply Means:

2 Sets, 3 Rows per Set, 4 Columns

Example:

Input

x = np.zeros((2,3,4))

Output

Set # 1 ---- [[[ 0.,  0.,  0.,  0.],  ---- Row 1
               [ 0.,  0.,  0.,  0.],  ---- Row 2
               [ 0.,  0.,  0.,  0.]], ---- Row 3 
    
Set # 2 ----  [[ 0.,  0.,  0.,  0.],  ---- Row 1
               [ 0.,  0.,  0.,  0.],  ---- Row 2
               [ 0.,  0.,  0.,  0.]]] ---- Row 3

Explanation: See? we have 2 Sets, 3 Rows per Set, and 4 Columns.

Note: Whenever you see a "Set of numbers" closed in double brackets from both ends. Consider it as a "set". And 3D and 3D+ arrays are always built on these "sets".

Failed to Connect to MySQL at localhost:3306 with user root

Steps:

1 - Right click on your task bar -->Start Task Manager

2 - Click on Services button (at bottom).

3 - Search for MYSQL57

4 - Right Click on MYSQL57 --> Start

Now again start your mysql-cmd-prompt or MYSQL WorkBench

How to display scroll bar onto a html table

Worth noting, that depending on your purpose (mine was the autofill results of a searchbar) you may want the height to be changeable, and for the scrollbar to only exist if the height exceeds that.

If you want that, replace height: x; with max-height: x;, and overflow:scroll with overflow:auto.

Additionally, you can use overflow-x and overflow-y if you want, and obviously the same thing works horizontally with width : x;

how to compare two elements in jquery

Random AirCoded example of testing "set equality" in jQuery:

$.fn.isEqual = function($otherSet) {
  if (this === $otherSet) return true;
  if (this.length != $otherSet.length) return false;
  var ret = true;
  this.each(function(idx) { 
    if (this !== $otherSet[idx]) {
       ret = false; return false;
    }
  });
  return ret;
};

var a=$('#start > div:last-child');
var b=$('#start > div.live')[0];

console.log($(b).isEqual(a));

How to output loop.counter in python jinja template?

if you are using django use forloop.counter instead of loop.counter

<ul>
{% for user in userlist %}
  <li>
      {{ user }} {{forloop.counter}}
  </li>
      {% if forloop.counter == 1 %}
          This is the First user
      {% endif %}
{% endfor %}
</ul>

Push item to associative array in PHP

Just change few snippet(use array_merge function):-

  $options['inputs']=array_merge($options['inputs'], $new_input);

How to call jQuery function onclick?

try this ..

HTML

<input type="submit" value="submit" name="submit" id="submit">

jQuery

$(document).ready(function () {
    $('#submit').click(function () {
        var url = $(location).attr('href');
        $('#spn_url').html('<strong>' + url + '</strong>');
    });
});

How to invoke function from external .c file in C?

There are many great contributions here, but let me add mine non the less.

First thing i noticed is, you did not make any promises in the main file that you were going to create a function known as add(). This count have been done like this in the main file:

    int add(int a, int b); 

before your main function, that way your main function would recognize the add function and try to look for its executable code. So essentially your files should be

Main.c

    int add(int a, int b);

    int main(void) {
        int result = add(5,6);
        printf("%d\n", result);
    }  

and // add.c

    int add(int a, int b) {
        return a + b;
    }

How to format a number as percentage in R?

Base R

I much prefer to use sprintf which is available in base R.

sprintf("%0.1f%%", .7293827 * 100)
[1] "72.9%"

I especially like sprintf because you can also insert strings.

sprintf("People who prefer %s over %s: %0.4f%%", 
        "Coke Classic", 
        "New Coke",
        .999999 * 100)
[1] "People who prefer Coke Classic over New Coke: 99.9999%"

It's especially useful to use sprintf with things like database configurations; you just read in a yaml file, then use sprintf to populate a template without a bunch of nasty paste0's.

Longer motivating example

This pattern is especially useful for rmarkdown reports, when you have a lot of text and a lot of values to aggregate.

Setup / aggregation:

library(data.table) ## for aggregate

approval <- data.table(year = trunc(time(presidents)), 
                       pct = as.numeric(presidents) / 100,
                       president = c(rep("Truman", 32),
                                     rep("Eisenhower", 32),
                                     rep("Kennedy", 12),
                                     rep("Johnson", 20),
                                     rep("Nixon", 24)))
approval_agg <- approval[i = TRUE,
                         j = .(ave_approval = mean(pct, na.rm=T)), 
                         by = president]
approval_agg
#     president ave_approval
# 1:     Truman    0.4700000
# 2: Eisenhower    0.6484375
# 3:    Kennedy    0.7075000
# 4:    Johnson    0.5550000
# 5:      Nixon    0.4859091

Using sprintf with vectors of text and numbers, outputting to cat just for newlines.

approval_agg[, sprintf("%s approval rating: %0.1f%%",
                       president,
                       ave_approval * 100)] %>% 
  cat(., sep = "\n")
# 
# Truman approval rating: 47.0%
# Eisenhower approval rating: 64.8%
# Kennedy approval rating: 70.8%
# Johnson approval rating: 55.5%
# Nixon approval rating: 48.6%

Finally, for my own selfish reference, since we're talking about formatting, this is how I do commas with base R:

30298.78 %>% round %>% prettyNum(big.mark = ",")
[1] "30,299"

jQuery: how to change title of document during .ready()?

If you have got a serverside script get_title.php that echoes the current title session this works fine in jQuery:

$.get('get_title.php',function(*respons*){
    title=*respons* + 'whatever you want'   
    $(document).attr('title',title)
})

C++ Dynamic Shared Library on Linux

On top of previous answers, I'd like to raise awareness about the fact that you should use the RAII (Resource Acquisition Is Initialisation) idiom to be safe about handler destruction.

Here is a complete working example:

Interface declaration: Interface.hpp:

class Base {
public:
    virtual ~Base() {}
    virtual void foo() const = 0;
};

using Base_creator_t = Base *(*)();

Shared library content:

#include "Interface.hpp"

class Derived: public Base {
public:
    void foo() const override {}
};

extern "C" {
Base * create() {
    return new Derived;
}
}

Dynamic shared library handler: Derived_factory.hpp:

#include "Interface.hpp"
#include <dlfcn.h>

class Derived_factory {
public:
    Derived_factory() {
        handler = dlopen("libderived.so", RTLD_NOW);
        if (! handler) {
            throw std::runtime_error(dlerror());
        }
        Reset_dlerror();
        creator = reinterpret_cast<Base_creator_t>(dlsym(handler, "create"));
        Check_dlerror();
    }

    std::unique_ptr<Base> create() const {
        return std::unique_ptr<Base>(creator());
    }

    ~Derived_factory() {
        if (handler) {
            dlclose(handler);
        }
    }

private:
    void * handler = nullptr;
    Base_creator_t creator = nullptr;

    static void Reset_dlerror() {
        dlerror();
    }

    static void Check_dlerror() {
        const char * dlsym_error = dlerror();
        if (dlsym_error) {
            throw std::runtime_error(dlsym_error);
        }
    }
};

Client code:

#include "Derived_factory.hpp"

{
    Derived_factory factory;
    std::unique_ptr<Base> base = factory.create();
    base->foo();
}

Note:

  • I put everything in header files for conciseness. In real life you should of course split your code between .hpp and .cpp files.
  • To simplify, I ignored the case where you want to handle a new/delete overload.

Two clear articles to get more details:

Java unsupported major minor version 52.0

Your code was compiled with Java Version 1.8 while it is being executed with Java Version 1.7 or below.

In your case it seems that two different Java installations are used, the newer to compile and the older to execute your code.

Try recompiling your code with Java 1.7 or upgrade your Java Plugin.

CSV new-line character seen in unquoted field error

This worked for me on OSX.

# allow variable to opened as files
from io import StringIO

# library to map other strange (accented) characters back into UTF-8
from unidecode import unidecode

# cleanse input file with Windows formating to plain UTF-8 string
with open(filename, 'rb') as fID:
    uncleansedBytes = fID.read()
    # decode the file using the correct encoding scheme
    # (probably this old windows one) 
    uncleansedText = uncleansedBytes.decode('Windows-1252')

    # replace carriage-returns with new-lines
    cleansedText = uncleansedText.replace('\r', '\n')

    # map any other non UTF-8 characters into UTF-8
    asciiText = unidecode(cleansedText)

# read each line of the csv file and store as an array of dicts, 
# use first line as field names for each dict. 
reader = csv.DictReader(StringIO(cleansedText))
for line_entry in reader:
    # do something with your read data 

How do I create an empty array/matrix in NumPy?

Depending on what you are using this for, you may need to specify the data type (see 'dtype').

For example, to create a 2D array of 8-bit values (suitable for use as a monochrome image):

myarray = numpy.empty(shape=(H,W),dtype='u1')

For an RGB image, include the number of color channels in the shape: shape=(H,W,3)

You may also want to consider zero-initializing with numpy.zeros instead of using numpy.empty. See the note here.

Excel VBA Code: Compile Error in x64 Version ('PtrSafe' attribute required)

I think all you need to do for your function is just add PtrSafe: i.e. the first line of your first function should look like this:

Private Declare PtrSafe Function swe_azalt Lib "swedll32.dll" ......

How do I show multiple recaptchas on a single page?

This answer is an extension to @raphadko's answer.

If you need to extract manually the captcha code (like in ajax requests) you have to call:

grecaptcha.getResponse(widget_id)

But how can you retrieve the widget id parameter?

I use this definition of CaptchaCallback to store the widget id of each g-recaptcha box (as an HTML data attribute):

var CaptchaCallback = function() {
    jQuery('.g-recaptcha').each(function(index, el) {
        var widgetId = grecaptcha.render(el, {'sitekey' : 'your code'});
        jQuery(this).attr('data-widget-id', widgetId);
    });
};

Then I can call:

grecaptcha.getResponse(jQuery('#your_recaptcha_box_id').attr('data-widget-id'));

to extract the code.

Why I cannot cout a string?

Use c_str() to convert the std::string to const char *.

cout << "String is  : " << text.c_str() << endl ;

CSS3 Fade Effect

The scrolling effect is cause by specifying the generic 'background' property in your css instead of the more specific background-image. By setting the background property, the animation will transition between all properties.. Background-Color, Background-Image, Background-Position.. Etc Thus causing the scrolling effect..

E.g.

a {
-webkit-transition-property: background-image 300ms ease-in 200ms;
-moz-transition-property: background-image 300ms ease-in 200ms;
-o-transition-property: background-image 300ms ease-in 200ms;
transition: background-image 300ms ease-in 200ms;
}

Change the Blank Cells to "NA"

As of (dplyr 1.0.0) we can use across()

For all columns:

dat <- dat %>%
   mutate(across(everything(), ~ifelse(.=="", NA, as.character(.))))

For individual columns:

dat <- dat %>%
   mutate(across(c("Age","Gender"), ~ifelse(.=="", NA, as.character(.))))

As of (dplyr 0.8.0 above) the way this should be written has changed. Before it was, funs() in .funs (funs(name = f(.)). Instead of funs, now we use list (list(name = ~f(.)))

Note that there is also a much simpler way to list the column names ! (both the name of the column and column index work)

dat <- dat %>%
mutate_at(.vars = c("Age","Gender"),
    .funs = list(~ifelse(.=="", NA, as.character(.))))

Original Answer:

You can also use mutate_at in dplyr

dat <- dat %>%
mutate_at(vars(colnames(.)),
        .funs = funs(ifelse(.=="", NA, as.character(.))))

Select individual columns to change:

dat <- dat %>%
mutate_at(vars(colnames(.)[names(.) %in% c("Age","Gender")]),
        .funs = funs(ifelse(.=="", NA, as.character(.))))

Labeling file upload button

much easier use it

<input type="button" id="loadFileXml" value="Custom Button Name"onclick="document.getElementById('file').click();" />
<input type="file" style="display:none;" id="file" name="file"/>

How to merge two arrays in JavaScript and de-duplicate items

_x000D_
_x000D_
var array1 = ["one","two"];_x000D_
var array2 = ["two", "three"];_x000D_
var collectionOfTwoArrays = [...array1, ...array2];    _x000D_
var uniqueList = array => [...new Set(array)];_x000D_
console.log('Collection :');_x000D_
console.log(collectionOfTwoArrays);    _x000D_
console.log('Collection without duplicates :');_x000D_
console.log(uniqueList(collectionOfTwoArrays));
_x000D_
_x000D_
_x000D_

How to set null to a GUID property

extrac Guid values from database functions:

    #region GUID

    public static Guid GGuid(SqlDataReader reader, string field)
    {
        try
        {
            return reader[field] == DBNull.Value ? Guid.Empty : (Guid)reader[field];
        }
        catch { return Guid.Empty; }
    }

    public static Guid GGuid(SqlDataReader reader, int ordinal = 0)
    {
        try
        {
            return reader[ordinal] == DBNull.Value ? Guid.Empty : (Guid)reader[ordinal];
        }
        catch { return Guid.Empty; }
    }

    public static Guid? NGuid(SqlDataReader reader, string field)
    {
        try
        {
            if (reader[field] == DBNull.Value) return (Guid?)null; else return (Guid)reader[field];
        }
        catch { return (Guid?)null; }
    }

    public static Guid? NGuid(SqlDataReader reader, int ordinal = 0)
    {
        try
        {
            if (reader[ordinal] == DBNull.Value) return (Guid?)null; else return (Guid)reader[ordinal];
        }
        catch { return (Guid?)null; }
    }

    #endregion

How to get datetime in JavaScript?

try this:

_x000D_
_x000D_
var today = new Date();
var date = today.getFullYear()+'-'+(today.getMonth()+1)+'-'+today.getDate();
var time = today.getHours()+':'+today.getMinutes()+':'+today.getSeconds();
console.log(date + ' '+ time);
_x000D_
_x000D_
_x000D_

Create Django model or update if exists

Django has support for this, check get_or_create

person, created = Person.objects.get_or_create(name='abc')
if created:
    # A new person object created
else:
    # person object already exists

How to convert integer timestamp to Python datetime

datetime.datetime.fromtimestamp() is correct, except you are probably having timestamp in miliseconds (like in JavaScript), but fromtimestamp() expects Unix timestamp, in seconds.

Do it like that:

>>> import datetime
>>> your_timestamp = 1331856000000
>>> date = datetime.datetime.fromtimestamp(your_timestamp / 1e3)

and the result is:

>>> date
datetime.datetime(2012, 3, 16, 1, 0)

Does it answer your question?

EDIT: J.F. Sebastian correctly suggested to use true division by 1e3 (float 1000). The difference is significant, if you would like to get precise results, thus I changed my answer. The difference results from the default behaviour of Python 2.x, which always returns int when dividing (using / operator) int by int (this is called floor division). By replacing the divisor 1000 (being an int) with the 1e3 divisor (being representation of 1000 as float) or with float(1000) (or 1000. etc.), the division becomes true division. Python 2.x returns float when dividing int by float, float by int, float by float etc. And when there is some fractional part in the timestamp passed to fromtimestamp() method, this method's result also contains information about that fractional part (as the number of microseconds).

Javascript callback when IFRAME is finished loading?

I think the load event is right. What is not right is the way you use to retreive the content from iframe content dom.

What you need is the html of the page loaded in the iframe not the html of the iframe object.

What you have to do is to access the content document with iFrameObj.contentDocument. This returns the dom of the page loaded inside the iframe, if it is on the same domain of the current page.

I would retreive the content before removing the iframe.

I've tested in firefox and opera.

Then i think you can retreive your data with $(childDom).html() or $(childDom).find('some selector') ...

how to mysqldump remote db from local machine

One can invoke mysqldump locally against a remote server.

Example that worked for me:

mysqldump -h hostname-of-the-server -u mysql_user -p database_name > file.sql

I followed the mysqldump documentation on connection options.

How to create an array for JSON using PHP?

also for array you can use short annotattion:

$arr = [
    [
        "region" => "valore",
        "price" => "valore2"
    ],
    [
        "region" => "valore",
        "price" => "valore2"
    ],
    [
        "region" => "valore",
        "price" => "valore2"
    ]
];

echo json_encode($arr);

SELECT query with CASE condition and SUM()

Select SUM(CASE When CPayment='Cash' Then CAmount Else 0 End ) as CashPaymentAmount,
       SUM(CASE When CPayment='Check' Then CAmount Else 0 End ) as CheckPaymentAmount
from TableOrderPayment
Where ( CPayment='Cash' Or CPayment='Check' ) AND CDate<=SYSDATETIME() and CStatus='Active';

Adding a newline character within a cell (CSV)

I have the same issue, when I try to export the content of email to csv and still keep it break line when importing to excel.

I export the conent as this: ="Line 1"&CHAR(10)&"Line 2"

When I import it to excel(google), excel understand it as string. It still not break new line.

We need to trigger excel to treat it as formula by: Format -> Number | Scientific.

This is not the good way but it resolve my issue.

Twitter - share button, but with image

I used this code to solve this problem.

<a href="https://twitter.com/intent/tweet?url=myUrl&text=myTitle" target="_blank"><img src="path_to_my_image"/></a>

You can check the tweet-button documentation here tweet-button

SSLHandshakeException: No subject alternative names present

Unlike some browsers, Java follows the HTTPS specification strictly when it comes to the server identity verification (RFC 2818, Section 3.1) and IP addresses.

When using a host name, it's possible to fall back to the Common Name in the Subject DN of the server certificate, instead of using the Subject Alternative Name.

When using an IP address, there must be a Subject Alternative Name entry (of type IP address, not DNS name) in the certificate.

You'll find more details about the specification and how to generate such a certificate in this answer.

HTML Tags in Javascript Alert() method

alert() doesn't support HTML, but you have some alternatives to format your message.

You can use Unicode characters as others stated, or you can make use of the ES6 Template literals. For example:

...
.catch(function (error) {
  const alertMessage = `Error retrieving resource. Please make sure:
    • the resource server is accessible
    • you're logged in

    Error: ${error}`;
  window.alert(alertMessage);
}

Output: enter image description here

As you can see, it maintains the line breaks and spaces that we included in the variable, with no extra characters.

What's the difference between Unicode and UTF-8?

UTF-16 and UTF-8 are both encodings of Unicode. They are both Unicode; one is not more Unicode than the other.

Don't let an unfortunate historical artifact from Microsoft confuse you.

Indexing vectors and arrays with +:

Description and examples can be found in IEEE Std 1800-2017 § 11.5.1 "Vector bit-select and part-select addressing". First IEEE appearance is IEEE 1364-2001 (Verilog) § 4.2.1 "Vector bit-select and part-select addressing". Here is an direct example from the LRM:

logic [31: 0] a_vect;
logic [0 :31] b_vect;
logic [63: 0] dword;
integer sel;
a_vect[ 0 +: 8] // == a_vect[ 7 : 0]
a_vect[15 -: 8] // == a_vect[15 : 8]
b_vect[ 0 +: 8] // == b_vect[0 : 7]
b_vect[15 -: 8] // == b_vect[8 :15]
dword[8*sel +: 8] // variable part-select with fixed width

If sel is 0 then dword[8*(0) +: 8] == dword[7:0]
If sel is 7 then dword[8*(7) +: 8] == dword[63:56]

The value to the left always the starting index. The number to the right is the width and must be a positive constant. the + and - indicates to select the bits of a higher or lower index value then the starting index.

Assuming address is in little endian ([msb:lsb]) format, then if(address[2*pointer+:2]) is the equivalent of if({address[2*pointer+1],address[2*pointer]})

How to change the session timeout in PHP?

You can override values in php.ini from your PHP code using ini_set().

Unix ls command: show full path when using options

What about this trick...

ls -lrt -d -1 $PWD/{*,.*}

OR

ls -lrt -d -1 $PWD/*

I think this has problems with empty directories but if another poster has a tweak I'll update my answer. Also, you may already know this but this is probably be a good candidate for an alias given it's lengthiness.

[update] added some tweaks based on comments, thanks guys.

[update] as pointed out by the comments you may need to tweek the matcher expressions depending on the shell (bash vs zsh). I've re-added my older command for reference.

What does auto do in margin:0 auto?

From the CSS specification on Calculating widths and margins for Block-level, non-replaced elements in normal flow:

If both 'margin-left' and 'margin-right' are 'auto', their used values are equal. This horizontally centers the element with respect to the edges of the containing block.

C#: List All Classes in Assembly

I'd just like to add to Jon's example. To get a reference to your own assembly, you can use:

Assembly myAssembly = Assembly.GetExecutingAssembly();

System.Reflection namespace.

If you want to examine an assembly that you have no reference to, you can use either of these:

Assembly assembly = Assembly.ReflectionOnlyLoad(fullAssemblyName);
Assembly assembly = Assembly.ReflectionOnlyLoadFrom(fileName);

If you intend to instantiate your type once you've found it:

Assembly assembly = Assembly.Load(fullAssemblyName);
Assembly assembly = Assembly.LoadFrom(fileName);

See the Assembly class documentation for more information.

Once you have the reference to the Assembly object, you can use assembly.GetTypes() like Jon already demonstrated.

Scaling a System.Drawing.Bitmap to a given size while maintaining aspect ratio

The bitmap constructor has resizing built in.

Bitmap original = (Bitmap)Image.FromFile("DSC_0002.jpg");
Bitmap resized = new Bitmap(original,new Size(original.Width/4,original.Height/4));
resized.Save("DSC_0002_thumb.jpg");

http://msdn.microsoft.com/en-us/library/0wh0045z.aspx

If you want control over interpolation modes see this post.

Is it possible to declare two variables of different types in a for loop?

C++17: Yes! You should use a structured binding declaration. The syntax has been supported in gcc and clang since gcc-7 and clang-4.0 (clang live example). This allows us to unpack a tuple like so:

for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
    // ...
}

The above will give you:

  • int i set to 1
  • double f set to 1.0
  • std::string s set to "ab"

Make sure to #include <tuple> for this kind of declaration.

You can specify the exact types inside the tuple by typing them all out as I have with the std::string, if you want to name a type. For example:

auto [vec, i32] = std::tuple{std::vector<int>{3, 4, 5}, std::int32_t{12}}

A specific application of this is iterating over a map, getting the key and value,

std::unordered_map<K, V> m = { /*...*/ };
for (auto& [key, value] : m) {
   // ...
}

See a live example here


C++14: You can do the same as C++11 (below) with the addition of type-based std::get. So instead of std::get<0>(t) in the below example, you can have std::get<int>(t).


C++11: std::make_pair allows you to do this, as well as std::make_tuple for more than two objects.

for (auto p = std::make_pair(5, std::string("Hello World")); p.first < 10; ++p.first) {
    std::cout << p.second << std::endl;
}

std::make_pair will return the two arguments in a std::pair. The elements can be accessed with .first and .second.

For more than two objects, you'll need to use a std::tuple

for (auto t = std::make_tuple(0, std::string("Hello world"), std::vector<int>{});
        std::get<0>(t) < 10;
        ++std::get<0>(t)) {
    std::cout << std::get<1>(t) << std::endl; // cout Hello world
    std::get<2>(t).push_back(std::get<0>(t)); // add counter value to the vector
}

std::make_tuple is a variadic template that will construct a tuple of any number of arguments (with some technical limitations of course). The elements can be accessed by index with std::get<INDEX>(tuple_object)

Within the for loop bodies you can easily alias the objects, though you still need to use .first or std::get for the for loop condition and update expression

for (auto t = std::make_tuple(0, std::string("Hello world"), std::vector<int>{});
        std::get<0>(t) < 10;
        ++std::get<0>(t)) {
    auto& i = std::get<0>(t);
    auto& s = std::get<1>(t);
    auto& v = std::get<2>(t);
    std::cout << s << std::endl; // cout Hello world
    v.push_back(i); // add counter value to the vector
}

C++98 and C++03 You can explicitly name the types of a std::pair. There is no standard way to generalize this to more than two types though:

for (std::pair<int, std::string> p(5, "Hello World"); p.first < 10; ++p.first) {
    std::cout << p.second << std::endl;
}

The simplest way to comma-delimit a list?

StringBuffer sb = new StringBuffer();

for (int i = 0; i < myList.size(); i++)
{ 
    if (i > 0) 
    {
        sb.append(", ");
    }

    sb.append(myList.get(i)); 
}

Understanding unique keys for array children in React.js

Just add the unique key to the your Components

data.map((marker)=>{
    return(
        <YourComponents 
            key={data.id}     // <----- unique key
        />
    );
})

Applying styles to tables with Twitter Bootstrap

Just another good looking table. I added "table-hover" class because it gives a nice hovering effect.

   <h3>NATO Phonetic Alphabet</h3>    
   <table class="table table-striped table-bordered table-condensed table-hover">
   <thead>
    <tr> 
        <th>Letter</th>
        <th>Phonetic Letter</th>

    </tr>
    </thead>
  <tr>
    <th>A</th>
    <th>Alpha</th>

  </tr>
  <tr>
    <td>B</td>
    <td>Bravo</td>

  </tr>
  <tr>
    <td>C</td>
    <td>Charlie</td>

  </tr>

</table>

How to pass parameter to a promise function

Another way(Must Try):

_x000D_
_x000D_
var promise1 = new Promise(function(resolve, reject) {_x000D_
  resolve('Success!');_x000D_
});_x000D_
var extraData = 'ImExtraData';_x000D_
promise1.then(function(value) {_x000D_
  console.log(value, extraData);_x000D_
  // expected output: "Success!" "ImExtraData"_x000D_
}, extraData);
_x000D_
_x000D_
_x000D_

xlsxwriter: is there a way to open an existing worksheet in my workbook?

You can use the workbook.get_worksheet_by_name() feature: https://xlsxwriter.readthedocs.io/workbook.html#get_worksheet_by_name

According to https://xlsxwriter.readthedocs.io/changes.html the feature has been added on May 13, 2016.

"Release 0.8.7 - May 13 2016

-Fix for issue when inserting read-only images on Windows. Issue #352.

-Added get_worksheet_by_name() method to allow the retrieval of a worksheet from a workbook via its name.

-Fixed issue where internal file creation and modification dates were in the local timezone instead of UTC."

Resize on div element

DIV does not fire a resize event, so you won't be able to do exactly what you've coded, but you could look into monitoring DOM properties.

If you are actually working with something like resizables, and that is the only way for a div to change in size, then your resize plugin will probably be implementing a callback of its own.

How to make Visual Studio copy a DLL file to the output directory?

xcopy /y /d  "$(ProjectDir)External\*.dll" "$(TargetDir)"

You can also refer to a relative path, the next example will find the DLL in a folder located one level above the project folder. If you have multiple projects that use the DLL in a single solution, this places the source of the DLL in a common area reachable when you set any of them as the Startup Project.

xcopy /y /d  "$(ProjectDir)..\External\*.dll" "$(TargetDir)"

The /y option copies without confirmation. The /d option checks to see if a file exists in the target and if it does only copies if the source has a newer timestamp than the target.

I found that in at least newer versions of Visual Studio, such as VS2109, $(ProjDir) is undefined and had to use $(ProjectDir) instead.

Leaving out a target folder in xcopy should default to the output directory. That is important to understand reason $(OutDir) alone is not helpful.

$(OutDir), at least in recent versions of Visual Studio, is defined as a relative path to the output folder, such as bin/x86/Debug. Using it alone as the target will create a new set of folders starting from the project output folder. Ex: … bin/x86/Debug/bin/x86/Debug.

Combining it with the project folder should get you to the proper place. Ex: $(ProjectDir)$(OutDir).

However $(TargetDir) will provide the output directory in one step.

Microsoft's list of MSBuild macros for current and previous versions of Visual Studio

How to append output to the end of a text file

You can use the >> operator. This will append data from a command to the end of a text file.

To test this try running:

echo "Hi this is a test" >> textfile.txt

Do this a couple of times and then run:

cat textfile.txt

You'll see your text has been appended several times to the textfile.txt file.

Passing variables, creating instances, self, The mechanics and usage of classes: need explanation

class Foo          (object):
    # ^class name  #^ inherits from object

    bar = "Bar" #Class attribute.

    def __init__(self):
        #        #^ The first variable is the class instance in methods.  
        #        #  This is called "self" by convention, but could be any name you want.
        #^ double underscore (dunder) methods are usually special.  This one 
        #  gets called immediately after a new instance is created.

        self.variable = "Foo" #instance attribute.
        print self.variable, self.bar  #<---self.bar references class attribute
        self.bar = " Bar is now Baz"   #<---self.bar is now an instance attribute
        print self.variable, self.bar  

    def method(self, arg1, arg2):
        #This method has arguments.  You would call it like this:  instance.method(1, 2)
        print "in method (args):", arg1, arg2
        print "in method (attributes):", self.variable, self.bar


a = Foo() # this calls __init__ (indirectly), output:
                 # Foo bar
                 # Foo  Bar is now Baz
print a.variable # Foo
a.variable = "bar"
a.method(1, 2) # output:
               # in method (args): 1 2
               # in method (attributes): bar  Bar is now Baz
Foo.method(a, 1, 2) #<--- Same as a.method(1, 2).  This makes it a little more explicit what the argument "self" actually is.

class Bar(object):
    def __init__(self, arg):
        self.arg = arg
        self.Foo = Foo()

b = Bar(a)
b.arg.variable = "something"
print a.variable # something
print b.Foo.variable # Foo

python: how to get information about a function?

Or

help(list.append)

if you're generally poking around.

socket connect() vs bind()

The one liner : bind() to own address, connect() to remote address.

Quoting from the man page of bind()

bind() assigns the address specified by addr to the socket referred to by the file descriptor sockfd. addrlen specifies the size, in bytes, of the address structure pointed to by addr. Traditionally, this operation is called "assigning a name to a socket".

and, from the same for connect()

The connect() system call connects the socket referred to by the file descriptor sockfd to the address specified by addr.

To clarify,

  • bind() associates the socket with its local address [that's why server side binds, so that clients can use that address to connect to server.]
  • connect() is used to connect to a remote [server] address, that's why is client side, connect [read as: connect to server] is used.

What does FETCH_HEAD in Git mean?

The FETCH_HEAD is a reference to the tip of the last fetch, whether that fetch was initiated directly using the fetch command or as part of a pull. The current value of FETCH_HEAD is stored in the .git folder in a file named, you guessed it, FETCH_HEAD.

So if I issue:

git fetch https://github.com/ryanmaxwell/Fragaria

FETCH_HEAD may contain

3cfda7cfdcf9fb78b44d991f8470df56723658d3        https://github.com/ryanmaxwell/Fragaria

If I have the remote repo configured as a remote tracking branch then I can follow my fetch with a merge of the tracking branch. If I don't I can merge the tip of the last fetch directly using FETCH_HEAD.

git merge FETCH_HEAD

How to create a laravel hashed password

If you want to understand how excatly laravel works you can review the complete class on Github: https://github.com/illuminate/hashing/blob/master/BcryptHasher.php

But basically there are Three PHP methods involved on that:

$pasword = 'user-password';
// To create a valid password out of laravel Try out!
$cost=10; // Default cost
$password = password_hash($pasword, PASSWORD_BCRYPT, ['cost' => $cost]);

// To validate the password you can use
$hash = '$2y$10$NhRNj6QF.Bo6ePSRsClYD.4zHFyoQr/WOdcESjIuRsluN1DvzqSHm';

if (password_verify($pasword, $hash)) {
   echo 'Password is valid!';
} else {
   echo 'Invalid password.';
}

//Finally if you have a $hash but you want to know the information about that hash. 
print_r( password_get_info( $password_hash ));

The hashed password is same as laravel 5.x bcrypt password. No need to give salt and cost, it will take its default values.

Those methods has been implemented in the laravel class, but if you want to learn more please review the official documentation: http://php.net/manual/en/function.password-hash.php

com.sun.jdi.InvocationException occurred invoking method

The root cause is that when debugging the java debug interface will call the toString() of your class to show the class information in the pop up box, so if the toString method is not defined correctly, this may happen.

How can I convert the "arguments" object to an array in JavaScript?

Use Array.from(), which takes an array-like object (such as arguments) as argument and converts it to array:

_x000D_
_x000D_
(function() {_x000D_
  console.log(Array.from(arguments));_x000D_
}(1, 2, 3));
_x000D_
_x000D_
_x000D_

Note that it doesn't work in some older browsers like IE 11, so if you want to support these browsers, you should use Babel.

How to access the contents of a vector from a pointer to the vector in C++?

Access it like any other pointer value:

std::vector<int>* v = new std::vector<int>();

v->push_back(0);
v->push_back(12);
v->push_back(1);

int twelve = v->at(1);
int one = (*v)[2];

// iterate it
for(std::vector<int>::const_iterator cit = v->begin(), e = v->end; 
    cit != e;  ++cit)
{
    int value = *cit;
}

// or, more perversely
for(int x = 0; x < v->size(); ++x)
{
    int value = (*v)[x];
}

// Or -- with C++ 11 support
for(auto i : *v)
{
   int value = i;
}

Can I obtain method parameter name using Java reflection?

if you use the eclipse, see the bellow image to allow the compiler to store the information about method parameters

enter image description here

Scala list concatenation, ::: vs ++

Legacy. List was originally defined to be functional-languages-looking:

1 :: 2 :: Nil // a list
list1 ::: list2  // concatenation of two lists

list match {
  case head :: tail => "non-empty"
  case Nil          => "empty"
}

Of course, Scala evolved other collections, in an ad-hoc manner. When 2.8 came out, the collections were redesigned for maximum code reuse and consistent API, so that you can use ++ to concatenate any two collections -- and even iterators. List, however, got to keep its original operators, aside from one or two which got deprecated.

Why is JavaFX is not included in OpenJDK 8 on Ubuntu Wily (15.10)?

I use ubuntu 16.04 and because I already had openJDK installed, this command have solved the problem. Don't forget that JavaFX is part of OpenJDK.

sudo apt-get install openjfx

Ruby: Merging variables in to a string

The standard ERB templating system may work for your scenario.

def merge_into_string(animal, second_animal, action)
  template = 'The <%=animal%> <%=action%> the <%=second_animal%>'
  ERB.new(template).result(binding)
end

merge_into_string('tiger', 'deer', 'eats')
=> "The tiger eats the deer"

merge_into_string('bird', 'worm', 'finds')
=> "The bird finds the worm"

How to track untracked content?

First go to the Directory : vendor/plugins/open_flash_chart_2 and DELETE


THEN :

git rm --cached vendor/plugins/open_flash_chart_2  
git add .  
git commit -m "Message"  
git push -u origin master  

git status  

OUTPUT

On branch master
Your branch is up-to-date with 'origin/master'.
nothing to commit, working directory clean

How to sum data.frame column values?

to order after the colsum :

order(colSums(people),decreasing=TRUE)

if more than 20+ columns

order(colSums(people[,c(5:25)],decreasing=TRUE) ##in case of keeping the first 4 columns remaining.

Remove duplicates from a list of objects based on property in Java 8

If you can make use of equals, then filter the list by using distinct within a stream (see answers above). If you can not or don't want to override the equals method, you can filter the stream in the following way for any property, e.g. for the property Name (the same for the property Id etc.):

Set<String> nameSet = new HashSet<>();
List<Employee> employeesDistinctByName = employees.stream()
            .filter(e -> nameSet.add(e.getName()))
            .collect(Collectors.toList());

TSQL How do you output PRINT in a user defined function?

I have tended in the past to work on my functions in two stages. The first stage would be to treat them as fairly normal SQL queries and make sure that I am getting the right results out of it. After I am confident that it is performing as desired, then I would convert it into a UDF.

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

For others needing a key binding:

{ "keys": ["ctrl+="], "command": "upper_case" },
{ "keys": ["ctrl+-"], "command": "lower_case" }

UnicodeEncodeError: 'ascii' codec can't encode character u'\xe9' in position 7: ordinal not in range(128)

You need to encode Unicode explicitly before writing to a file, otherwise Python does it for you with the default ASCII codec.

Pick an encoding and stick with it:

f.write(printinfo.encode('utf8') + '\n')

or use io.open() to create a file object that'll encode for you as you write to the file:

import io

f = io.open(filename, 'w', encoding='utf8')

You may want to read:

before continuing.

How to loop through a JSON object with typescript (Angular2)

Assuming your json object from your GET request looks like the one you posted above simply do:

let list: string[] = [];

json.Results.forEach(element => {
    list.push(element.Id);
});

Or am I missing something that prevents you from doing it this way?

firestore: PERMISSION_DENIED: Missing or insufficient permissions

make sure your DB is not empty nor your query is for collection whom not exist

Automatically run %matplotlib inline in IPython Notebook

Create any .py file in ~/.ipython/profile_default/startup/ containing

get_ipython().magic('matplotlib inline')

What’s the difference between Response.Write() andResponse.Output.Write()?

See this:

The difference between Response.Write() and Response.Output.Write() in ASP.NET. The short answer is that the latter gives you String.Format-style output and the former doesn't. The long answer follows.

In ASP.NET the Response object is of type HttpResponse and when you say Response.Write you're really saying (basically) HttpContext.Current.Response.Write and calling one of the many overloaded Write methods of HttpResponse.

Response.Write then calls .Write() on it's internal TextWriter object:

public void Write(object obj){ this._writer.Write(obj);} 

HttpResponse also has a Property called Output that is of type, yes, TextWriter, so:

public TextWriter get_Output(){ return this._writer; } 

Which means you can do the Response whatever a TextWriter will let you. Now, TextWriters support a Write() method aka String.Format, so you can do this:

Response.Output.Write("Scott is {0} at {1:d}", "cool",DateTime.Now);

But internally, of course, this is happening:

public virtual void Write(string format, params object[] arg)
{ 
this.Write(string.Format(format, arg)); 
}

Include PHP inside JavaScript (.js) files

This is somewhat tricky since PHP gets evaluated server-side and javascript gets evaluated client side.

I would call your PHP file using an AJAX call from inside javascript and then use JS to insert the returned HTML somewhere on your page.

Collections.emptyList() vs. new instance

I would go with Collections.emptyList() if the returned list is not being modified in any way (as the list is immutable), otherwise I would go with option 2.

The benefit of Collections.emptyList() is that the same static instance is returned each time and so there is not instance creation occurring for each call.

How can I check if a View exists in a Database?

If you want to check the validity and consistency of all the existing views you can use the following query

declare @viewName sysname
declare @cmd sysname
DECLARE check_cursor CURSOR FOR 
SELECT cast('['+SCHEMA_NAME(schema_id)+'].['+name+']' as sysname) AS viewname
FROM sys.views

OPEN check_cursor
FETCH NEXT FROM check_cursor 
INTO @viewName

WHILE @@FETCH_STATUS = 0
BEGIN

set @cmd='select * from '+@viewName
begin try
exec (@cmd)
end try
begin catch
print 'Error: The view '+@viewName+' is corrupted .'
end catch
FETCH NEXT FROM check_cursor 
INTO @viewName
END 
CLOSE check_cursor;
DEALLOCATE check_cursor;

Getting GET "?" variable in laravel

It is not very nice to use native php resources like $_GET as Laravel gives us easy ways to get the variables. As a matter of standard, whenever possible use the resources of the laravel itself instead of pure PHP.

There is at least two modes to get variables by GET in Laravel ( Laravel 5.x or greater):

Mode 1

Route:

Route::get('computers={id}', 'ComputersController@index');

Request (POSTMAN or client...):

http://localhost/api/computers=500

Controler - You can access the {id} paramter in the Controlller by:

public function index(Request $request, $id){
   return $id;
}

Mode 2

Route:

Route::get('computers', 'ComputersController@index');

Request (POSTMAN or client...):

http://localhost/api/computers?id=500

Controler - You can access the ?id paramter in the Controlller by:

public function index(Request $request){
   return $request->input('id');
}

How to create PDF files in Python

I suggest Pdfkit. (installation guide)

It creates pdf from html files. I chose it to create pdf in 2 steps from my Python Pyramid stack:

  1. Rendering server-side with mako templates with the style and markup you want for you pdf document
  2. Executing pdfkit.from_string(...) method by passing the rendered html as parameter

This way you get a pdf document with styling and images supported.

You can install it as follows :

  • using pip

    pip install pdfkit

  • You will also need to install wkhtmltopdf (on Ubuntu).

Error: Cannot find module 'ejs'

STEP 1

See npm ls | grep ejs at root level of your project to check if you have already added ejs dependency to your project.

If not, add it as dependencies to your project. (I prefer adding dependency to package.json instead of npm installing the module.)

eg.

{                                                                                                      
  "name": "musicpedia",                                                                                
  "version": "0.0.0",                                                                                  
  "private": true,                                                                                     
  "scripts": {                                                                                         
    "start": "node ./bin/www"                                                                          
  },                                                                                                   
  "dependencies": {                                                                                    
    "body-parser": "~1.15.1",                                                                          
    "cookie-parser": "~1.4.3",                                                                         
    "debug": "~2.2.0",                                                                                 
    "express": "~4.13.4",                                                                              
    "jade": "~1.11.0",                                                                                 
    "ejs": "^1.0.0",                                                                                                                                                            
    "morgan": "~1.7.0",                                                                                
    "serve-favicon": "~2.3.0"                                                                          
  }                                                                                                    
}   

STEP 2 download the dependencies

npm install

STEP 3 check ejs module

$ npm ls | grep ejs
[email protected] /Users/prayagupd/nodejs-fkers/musicpedia
+-- [email protected]

How do you use global variables or constant values in Ruby?

Variable scope in Ruby is controlled by sigils to some degree. Variables starting with $ are global, variables with @ are instance variables, @@ means class variables, and names starting with a capital letter are constants. All other variables are locals. When you open a class or method, that's a new scope, and locals available in the previous scope aren't available.

I generally prefer to avoid creating global variables. There are two techniques that generally achieve the same purpose that I consider cleaner:

  1. Create a constant in a module. So in this case, you would put all the classes that need the offset in the module Foo and create a constant Offset, so then all the classes could access Foo::Offset.

  2. Define a method to access the value. You can define the method globally, but again, I think it's better to encapsulate it in a module or class. This way the data is available where you need it and you can even alter it if you need to, but the structure of your program and the ownership of the data will be clearer. This is more in line with OO design principles.

What is __future__ in Python used for and how/when to use it, and how it works

When you do

from __future__ import whatever

You're not actually using an import statement, but a future statement. You're reading the wrong docs, as you're not actually importing that module.

Future statements are special -- they change how your Python module is parsed, which is why they must be at the top of the file. They give new -- or different -- meaning to words or symbols in your file. From the docs:

A future statement is a directive to the compiler that a particular module should be compiled using syntax or semantics that will be available in a specified future release of Python. The future statement is intended to ease migration to future versions of Python that introduce incompatible changes to the language. It allows use of the new features on a per-module basis before the release in which the feature becomes standard.

If you actually want to import the __future__ module, just do

import __future__

and then access it as usual.

Casting interfaces for deserialization in JSON.NET

Nicholas Westby provided a great solution in a awesome article.

If you want Deserializing JSON to one of many possible classes that implement an interface like that:

public class Person
{
    public IProfession Profession { get; set; }
}

public interface IProfession
{
    string JobTitle { get; }
}

public class Programming : IProfession
{
    public string JobTitle => "Software Developer";
    public string FavoriteLanguage { get; set; }
}

public class Writing : IProfession
{
    public string JobTitle => "Copywriter";
    public string FavoriteWord { get; set; }
}

public class Samples
{
    public static Person GetProgrammer()
    {
        return new Person()
        {
            Profession = new Programming()
            {
                FavoriteLanguage = "C#"
            }
        };
    }
}

You can use a custom JSON converter:

public class ProfessionConverter : JsonConverter
{
    public override bool CanWrite => false;
    public override bool CanRead => true;
    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(IProfession);
    }
    public override void WriteJson(JsonWriter writer,
        object value, JsonSerializer serializer)
    {
        throw new InvalidOperationException("Use default serialization.");
    }

    public override object ReadJson(JsonReader reader,
        Type objectType, object existingValue,
        JsonSerializer serializer)
    {
        var jsonObject = JObject.Load(reader);
        var profession = default(IProfession);
        switch (jsonObject["JobTitle"].Value())
        {
            case "Software Developer":
                profession = new Programming();
                break;
            case "Copywriter":
                profession = new Writing();
                break;
        }
        serializer.Populate(jsonObject.CreateReader(), profession);
        return profession;
    }
}

And you will need to decorate the "Profession" property with a JsonConverter attribute to let it know to use your custom converter:

    public class Person
    {
        [JsonConverter(typeof(ProfessionConverter))]
        public IProfession Profession { get; set; }
    }

And then, you can cast your class with an Interface:

Person person = JsonConvert.DeserializeObject<Person>(jsonString);

Implicit type conversion rules in C++ operators

The type of the expression, when not both parts are of the same type, will be converted to the biggest of both. The problem here is to understand which one is bigger than the other (it does not have anything to do with size in bytes).

In expressions in which a real number and an integer number are involved, the integer will be promoted to real number. For example, in int + float, the type of the expression is float.

The other difference are related to the capability of the type. For example, an expression involving an int and a long int will result of type long int.