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What does if __name__ == “__main__”: do?
Given the following code, what does the if __name__ == "__main__": do?
33 Answers
33...
In Python, how do I indicate I'm overriding a method?
...an think of a better solution please post it here!
def overrides(interface_class):
def overrider(method):
assert(method.__name__ in dir(interface_class))
return method
return overrider
It works as follows:
class MySuperInterface(object):
def my_method(self):
p...
How do I read any request header in PHP
...instead of all headers, the quickest method is:
<?php
// Replace XXXXXX_XXXX with the name of the header you need in UPPERCASE (and with '-' replaced by '_')
$headerStringValue = $_SERVER['HTTP_XXXXXX_XXXX'];
ELSE IF: you run PHP as an Apache module or, as of PHP 5.4, using FastCGI (simple me...
What is the difference between quiet NaN and signaling NaN?
...+ in this answer instead of C because it offers the convenient std::numeric_limits::quiet_NaN and std::numeric_limits::signaling_NaN which I could not find in C conveniently.
I could not however find a function to classify if a NaN is sNaN or qNaN, so let's just print out the NaN raw bytes:
main.c...
How to handle floats and decimal separators with html5 input type number
Im building web app which is mainly for mobile browsers. Im using input fields with number type, so (most) mobile browsers invokes only number keyboard for better user experience. This web app is mainly used in regions where decimal separator is comma, not dot, so I need to handle both decimal separ...
How do I create an average from a Ruby array?
...
Try this:
arr = [5, 6, 7, 8]
arr.inject{ |sum, el| sum + el }.to_f / arr.size
=> 6.5
Note the .to_f, which you'll want for avoiding any problems from integer division. You can also do:
arr = [5, 6, 7, 8]
arr.inject(0.0) { |sum, el| sum + el } / arr.size
=> 6.5
You can define it...
What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?
...
GCC has:
-- Built-in Function: int __builtin_clz (unsigned int x)
Returns the number of leading 0-bits in X, starting at the most
significant bit position. If X is 0, the result is undefined.
-- Built-in Function: int __builtin_clzl (unsigned long...
Docker can't connect to docker daemon
...s
See: Get started with Docker Machine and a local VM.
Install Docker.app on macOS
Alternatively to above solution, you can install a Docker app by:
brew cask install docker
Check this post for more details. See also: Cannot connect to the Docker daemon on macOS
...
Timer function to provide time in nano seconds using C++
...repeatedly in a loop is correct.
For Linux (and BSD) you want to use clock_gettime().
#include <sys/time.h>
int main()
{
timespec ts;
// clock_gettime(CLOCK_MONOTONIC, &ts); // Works on FreeBSD
clock_gettime(CLOCK_REALTIME, &ts); // Works on Linux
}
For windows you want t...
Why doesn't Python have a sign function?
...y removed and replaced by sign! Have you never implemented a class with a __cmp__ method? Have you never called cmp and specified a custom comparator function?
In summary, I've found myself wanting a sign function too, but copysign with the first argument being 1 will work just fine. I disagree ...