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What exactly do “u” and “r” string flags do, and what are raw string literals?
...ng literals, each backslash must be doubled up to avoid being taken as the start of an escape sequence.
This syntax variant exists mostly because the syntax of regular expression patterns is heavy with backslashes (but never at the end, so the "except" clause above doesn't matter) and it looks a bi...
Select distinct values from a table field
...provide an order_by() in the
QuerySet, and the fields in order_by() must start with the fields in
distinct(), in the same order.
For example, SELECT DISTINCT ON (a) gives you the first row for each
value in column a. If you don’t specify an order, you’ll get some
arbitrary row.
If...
Heroku error: “Permission denied (public key)”
...ollow the instructions that were detialed on the official website -Getting Started with Your Facebook App on Heroku
Even though it is quite detialed especially the video it is quite annoying to note that they do not mention having to set up SSH keys . Either it is set by default ( i dont know ) or...
Get the closest number out of an array
...(and can guarantee the array is sorted in ascending order), this is a good starting point:
<html>
<head></head>
<body>
<script language="javascript">
function closest (num, arr) {
var mid;
var lo = 0;
...
python numpy ValueError: operands could not be broadcast together with shapes
...When operating on two arrays, NumPy compares their shapes element-wise. It starts with the trailing dimensions, and works its way forward. Two dimensions are compatible when:
they are equal, or
one of them is 1
In other words, if you are trying to multiply two matrices (in the linear ...
Is there a performance difference between a for loop and a for-each loop?
...
doesn't the third one start from i=1 on first time it goes through the loop, skipping first element. and it being a for loop is unnecessary. int n=strings.length; while(n-->0) { System.out.println(" "+n+" "+strings[n]); }
...
Show Youtube video source into HTML5 video tag?
...I here: https://developers.google.com/youtube/iframe_api_reference#Getting_Started
The Code can also be found below
In your HTML:
<div id="player"></div>
In your Javascript:
var onPlayerReady = function(event) {
event.target.playVideo();
};
// The first argument of YT.P...
Android Studio/Intellij Idea: “Table of Contents” for a class
... the Enter key or the F4 key. To easily locate an item in the
list, just start typing its name.
Also, as danny117 points out, you can use Alt/⌘+7 to show / hide the same content in a side panel view (shown above in Chris Jester-Young's answer).
...
Re-entrant locks in C#
...n which the current thread already has a lock will work just fine.
If you start locking on different objects, that's when you have to be careful. Pay particular attention to:
Always acquire locks on a given number of objects in the same sequence.
Always release locks in the reverse sequence to ho...
Changing CSS Values with Javascript
...I was working on image transitions, and the CSS really slows down when you start putting a big image into 36 separate URI's for slicing. This just took a ton of overhead off my script. Thanks!
– Jason Maggard
Feb 3 '16 at 1:24
...