Here’s a quick test of a simple case: a program to read a list of numbers from standard input and XOR all of the numbers. iostream version: #include <iostream> int main(int argc, char **argv) { int parity = 0; int x; while (std::cin >> x) parity ^= x; std::cout << parity << std::endl; return 0; … Read more
Ray’s solution is good. However, on my machine it is about 2.5x faster to use numpy.sum in place of numpy.min: In [13]: %timeit np.isnan(np.min(x)) 1000 loops, best of 3: 244 us per loop In [14]: %timeit np.isnan(np.sum(x)) 10000 loops, best of 3: 97.3 us per loop Unlike min, sum doesn’t require branching, which on modern … Read more
If you actually want to benchmark real world code, use tools like Xdebug and XHProf. Xdebug is great for when you’re working in dev/staging, and XHProf is a great tool for production and it’s safe to run it there (as long as you read the instructions). The results of any one single page load aren’t … Read more
In terms of speed, it’s no competition for empty lists/dicts: >>> from timeit import timeit >>> timeit(“[]”) 0.040084982867934334 >>> timeit(“list()”) 0.17704233359267718 >>> timeit(“{}”) 0.033620194745424214 >>> timeit(“dict()”) 0.1821558326547077 and for non-empty: >>> timeit(“[1,2,3]”) 0.24316302770330367 >>> timeit(“list((1,2,3))”) 0.44744206316727286 >>> timeit(“list(foo)”, setup=”foo=(1,2,3)”) 0.446036018543964 >>> timeit(“{‘a’:1, ‘b’:2, ‘c’:3}”) 0.20868602015059423 >>> timeit(“dict(a=1, b=2, c=3)”) 0.47635635255323905 >>> timeit(“dict(bar)”, setup=”bar=[(‘a’, 1), (‘b’, … Read more
Best results you’ll get with Shared Memory solution. Named pipes are only 16% better than TCP sockets. Results are get with IPC benchmarking: System: Linux (Linux ubuntu 4.4.0 x86_64 i7-6700K 4.00GHz) Message: 128 bytes Messages count: 1000000 Pipe benchmark: Message size: 128 Message count: 1000000 Total duration: 27367.454 ms Average duration: 27.319 us Minimum duration: … Read more
I’ve read dynamic makes the compiler run again, but what it does. Does it have to recompile whole method with the dynamic used as a parameter or rather those lines with dynamic behavior/context(?) Here’s the deal. For every expression in your program that is of dynamic type, the compiler emits code that generates a single … Read more
This is the function that I use for this calculation: public static int binlog( int bits ) // returns 0 for bits=0 { int log = 0; if( ( bits & 0xffff0000 ) != 0 ) { bits >>>= 16; log = 16; } if( bits >= 256 ) { bits >>>= 8; log += … Read more
I’m the author of Java Matrix Benchmark (JMatBench) and I’ll give my thoughts on this discussion. There are significant difference between Java libraries and while there is no clear winner across the whole range of operations, there are a few clear leaders as can be seen in the latest performance results (October 2013). If you … Read more
The other plus of using RecycleView is animation, it can be done in two lines of code RecyclerView.ItemAnimator itemAnimator = new DefaultItemAnimator(); recyclerView.setItemAnimator(itemAnimator); But the widget is still raw, e.g you can’t create header and footer.
Why should LINQ be faster? It also uses loops internally. Most of the times, LINQ will be a bit slower because it introduces overhead. Do not use LINQ if you care much about performance. Use LINQ because you want shorter better readable and maintainable code.