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Why use def main()? [duplicate]
...ng this if, we can make Python behave like them, which feels more familiar for many people.
Code will be cleaner, easier to read, and better organized. (yeah, I know this is subjective)
It will be possible to import that python code as a module without nasty side-effects.
This means it will be po...
Writing your own STL Container
...ry should be one of std::input_iterator_tag, std::output_iterator_tag,std::forward_iterator_tag,std::bidirectional_iterator_tag,std::random_access_iterator_tag. Also note that the below is technically more strict than required, but this is the idea. Note that the vast majority of the "standard" func...
How to use if - else structure in a batch file?
...but of course that only works in this example, it isn't a general solution for doing if-else.
There are lots of ways around this. Here is a few ideas, all are quite ugly but hey, this is (or at least was) DOS!
@echo off
set one=1
set two=2
REM Example 1
IF %one%_%two%==1_1 (
echo Example 1 f...
C library function to perform sort
...
qsort() is the function you're looking for. You call it with a pointer to your array of data, the number of elements in that array, the size of each element and a comparison function.
It does its magic and your array is sorted in-place. An example follows:
#incl...
Remove last item from array
...
Doesn't work for one-element arrays: [1].splice(-1, 1) => [1]
– Tvaroh
Nov 1 '14 at 8:38
144
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Saving a Numpy array as an image
... type of a Numpy array. How would I write it to disk it as an image? Any format works (png, jpeg, bmp...). One important constraint is that PIL is not present.
...
performSelector may cause a leak because its selector is unknown
...
Solution
The compiler is warning about this for a reason. It's very rare that this warning should simply be ignored, and it's easy to work around. Here's how:
if (!_controller) { return; }
SEL selector = NSSelectorFromString(@"someMethod");
IMP imp = [_controller meth...
What is the difference between char s[] and char *s?
...doesn't have to be in read-only memory (some implementations have no MMUs, for example). The n1362 c1x draft simply states that modifying such an array causes undefined behavior. But +1 anyway, since relying on that behavior is a silly thing to do.
– paxdiablo
...
What does new self(); mean in PHP?
... same as :
self::$_instance = new MyClass();
Edit : a couple more informations, after the comments.
If you have two classes that extend each other, you have two situations :
getInstance is defined in the child class
getInstance is defined in the parent class
The first situation would lo...
Test if lists share any items in python
... are stored using a hash table in Python, searching them is O(1) (see here for more information about complexity of operators in Python). Theoretically, this is O(n+m) on average for n and m objects in lists a and b. But 1) it must first create sets out of the lists, which can take a non-negligible ...