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Is there a performance difference between a for loop and a for-each loop?
What, if any, is the performance difference between the following two loops?
16 Answers
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UIPanGestureRecognizer - Only vertical or horizontal
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Just do this for the vertical pan gesture recognizer, it works for me:
- (BOOL)gestureRecognizerShouldBegin:(UIPanGestureRecognizer *)panGestureRecognizer {
CGPoint velocity = [panGestureRecognizer velocityInView:someView];
retur...
What is the difference between quiet NaN and signaling NaN?
...ented in software. A signalling NaN will produce a signal, usually in the form of exception from the FPU. Whether the exception is thrown depends on the state of the FPU.
C++11 adds a few language controls over the floating-point environment and provides standardized ways to create and test for N...
How do I get the base URL with PHP?
...aces, commas, carriage return, etc. Anything that is not a valid character for a domain. Check the PHP builtin parse_url function for an example.
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What is the best regular expression to check if a string is a valid URL?
...C 3987 (http://www.faqs.org/rfcs/rfc3987.html). These are in PCRE syntax.
For absolute IRIs (internationalized):
/^[a-z](?:[-a-z0-9\+\.])*:(?:\/\/(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\x{A0}-\x{D7FF}\x{F900}-\x{FDCF}\x{FDF0}-\x{FFEF}\x{10000}-\x{1FFFD}\x{20000}-\x{2FFFD}\x{30000}-\x{3FFFD}\x{40000}-...
Combining C++ and C - how does #ifdef __cplusplus work?
...s that can't be built with C linkage. That means no classes or templates, for example.
extern "C" blocks nest nicely. There's also extern "C++" if you find yourself hopelessly trapped inside of extern "C" regions, but it isn't such a good idea from a cleanliness perspective.
Now, specifically re...
Timer function to provide time in nano seconds using C++
I wish to calculate the time it took for an API to return a value.
The time taken for such an action is in the space of nano seconds. As the API is a C++ class/function, I am using the timer.h to caculate the same:
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Class method decorator with self arguments?
...es how the internal function _impl can access self to manipulate that self for whatever purpose. I needed to build a simple method decorator that incremented a self.id on a subset of the methods in a class, and only those methods in a class that had the "@" decoration syntax applied to it. That Syn...
How to convert list of tuples to multiple lists?
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franklsf95 goes for performance in his answer and opts for list.append(), but they are not optimal.
Adding list comprehensions, I ended up with the following:
def t1(zs):
xs, ys = zip(*zs)
return xs, ys
def t2(zs):
xs, ys = []...
Stack smashing detected
I am executing my a.out file. After execution the program runs for some time then exits with the message:
9 Answers
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