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What does if __name__ == “__main__”: do?
Given the following code, what does the if __name__ == "__main__": do?
33 Answers
33...
How to show all shared libraries used by executables in Linux?
... will look something like this:
1 /lib64/libexpat.so.0
1 /lib64/libgcc_s.so.1
1 /lib64/libnsl.so.1
1 /lib64/libpcre.so.0
1 /lib64/libproc-3.2.7.so
1 /usr/lib64/libbeecrypt.so.6
1 /usr/lib64/libbz2.so.1
1 /usr/lib64/libelf.so.1
1 /usr/lib64/libpopt.so.0
1 /usr/lib64/librpm-4.4.so...
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 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...
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 ...
What does extern inline do?
... I'd like to add that for Microsoft's Visual C++, there's a __forceinline keyword that will enforce your function getting inlined. This is obviously a compiler-specific extension only for VC++.
– untitled8468927
Jan 17 '14 at 12:12
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