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In Django, how do I check if a user is in a certain group?
...add(group) # user is now in the "Editor" group
then user.groups.all() returns [<Group: Editor>].
Alternatively, and more directly, you can check if a a user is in a group by:
if django_user.groups.filter(name = groupname).exists():
...
Note that groupname can also be the ac...
What is a proper naming convention for MySQL FKs?
...constraints. If a name is not given, InnoDB creates a unique name automatically.
In any case, this is the convention that I use:
fk_[referencing table name]_[referenced table name]_[referencing field name]
Example:
CREATE TABLE users(
user_id int,
name varchar(100)
);
CREATE T...
Find running median from a stream of integers
...based solution works is explained below:
For the first two elements add smaller one to the maxHeap on the left, and bigger one to the minHeap on the right. Then process stream data one by one,
Step 1: Add next item to one of the heaps
if next item is smaller than maxHeap root add it to maxHea...
Get a random boolean in python?
... but I found that random.getrandbits(1) to be quite a lot faster. If you really want a boolean instead of a long then
bool(random.getrandbits(1))
is still about twice as fast as random.choice([True, False])
Both solutions need to import random
If utmost speed isn't to priority then random.choic...
How to use C++ in Go
In the new Go language, how do I call C++ code? In other words, how can I wrap my C++ classes and use them in Go?
12 Answ...
How to validate an e-mail address in swift?
...s quite funny that ............ as well as (1) the regex being utterly, totally incorrect (2) the regex (even within the context of what it's trying to do) has major errors (3) the Swift is wrong (4) even setting that aside, the style is totally wrong (5) not that it matters given all the rest but i...
How to find the operating system version using JavaScript?
...
If you list all of window.navigator's properties using
console.log(navigator);
You'll see something like this
# platform = Win32
# appCodeName = Mozilla
# appName = Netscape
# appVersion = 5.0 (Windows; en-US)
# language = en-US
# ...
What's the difference between echo, print, and print_r in PHP?
...s, although such usage is rare; echo is slightly faster than print. (Personally, I always use echo, never print.)
var_dump prints out a detailed dump of a variable, including its type and the type of any sub-items (if it's an array or an object). print_r prints a variable in a more human-readable f...
Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C
...
NOTE: All algorithms below are in C, but should be portable to your language of choice (just don't look at me when they're not as fast :)
Options
Low Memory (32-bit int, 32-bit machine)(from here):
unsigned int
reverse(register ...
do N times (declarative syntax)
...based on Array.forEach, without any library, just native vanilla.
To basically call something() 3 times, use:
[1,2,3].forEach(function(i) {
something();
});
considering the following function:
function something(){ console.log('something') }
The outpout will be
something
something
somethi...