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WebRTC vs Websockets: If WebRTC can do Video, Audio, and Data, why do I need Websockets? [closed]
So I'm looking to build a chat app that will allow video, audio, and text. I spent some time researching into Websockets and WebRTC to decide which to use. Since there are plenty of video and audio apps with WebRTC, this sounds like a reasonable choice, but are there other things I should consider? ...
Set “this” variable easily?
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There are two methods defined for all functions in JavaScript, call(), and apply(). The function syntax looks like:
call( /* object */, /* arguments... */ );
apply(/* object */, /* arguments[] */);
What these functions do is call the function they were inv...
How to flip background image using CSS?
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You can flip it horizontally with CSS...
a:visited {
-moz-transform: scaleX(-1);
-o-transform: scaleX(-1);
-webkit-transform: scaleX(-1);
transform: scaleX(-1);
filter: FlipH;
-ms-filter: "FlipH";
}
jsFiddle.
If you want ...
Does pandas iterrows have performance issues?
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Generally, iterrows should only be used in very, very specific cases. This is the general order of precedence for performance of various operations:
1) vectorization
2) using a custom cython routine
3) apply
a) reductions tha...
Converting file size in bytes to human-readable string
...he other hand, hard disk manufacturers like to use decimal, so they would call it ~1.6GB.
And just to be confusing, floppy disks use a mixture of the two systems - their 1MB is actually 1024000 bytes.
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PCH File in Xcode 6
...t; Other > PCH File > YourProject-Prefix.pch.
Make sure you display "All" and not "Basic". (Blue buttons)
Project > Build Settings > Search: "Prefix Header".
Under "Apple LLVM 7.0" you will get the Prefix Header key.
Type file directory. e.g: "$(SRCROOT)/$(PROJECT_NAME)/ProjectName-Prefi...
Get first key in a (possibly) associative array?
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2019 Update
Starting from PHP 7.3, there is a new built in function called array_key_first() which will retrieve the first key from the given array without resetting the internal pointer. Check out the documentation for more info.
You can use reset and key:
reset($array);
$first_key = key(...
What is the correct way to check for string equality in JavaScript?
...= operator can have very unexpected results due to the type-coercion internally, so using === is always the recommended approach.
For insight into this, and other "good vs. bad" parts of Javascript read up on Mr. Douglas Crockford and his work. There's a great Google Tech Talk where he summarizes ...
How to append something to an array?
...the push() function to append more than one value to an array in a single call:
// initialize array
var arr = ["Hi", "Hello", "Bonjour", "Hola"];
// append multiple values to the array
arr.push("Salut", "Hey");
// display all values
for (var i = 0; i < arr.length; i++) {
console.log(arr[i...
Copy files from one directory into an existing directory
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I really like this syntax, but for some reason it doesn't work with mv. Does anyone know why?
– Martin von Wittich
Sep 16 '13 at 11:18
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