dynamic-arrays

In my program I have a bunch of growing arrays where a new element is grown one by one to the end of the array. I identified Lists to be a speed bottleneck in a critical part of my program due to their slow access time in comparison with an array - switching to an array increased performance tremendously to an acceptable level. So to grow the array i'm using Array.Resize. This works well as my implementation restricts the array size to approximately 20 elements, so the O(N) performance of Array.Resize is bounded. But it would be better if there was a way to just increase an array by one

What's the purpose of ANYSIZE_ARRAY , located in WinNT.h? I see an MSDN blog post about it from 2004 but it doesn't make sense to me. I assume you are talking about this blog post . It is often used when a variable-sized (unknown at compile time) array is part of a struct: typedef struct { int CommonFlags int CountOfThings; THING Things[ANYSIZE_ARRAY]; //Things[1]; } THINGSANDFLAGS; To work with those structures you often first call the desired API to get the size of the data, then allocate a block of memory big enough and finally call the same API again so it can fill in the data... From this

Running this code: n = 5; x = zeros(n, 1); for ix=1:10 x(ix) = rand(); disp(getfield(whos('x'), 'bytes')) end outputs this: 40 40 40 40 40 48 56 64 72 80 which seems to indicate that when Matlab resizes a vector, it resizes it to have exactly as much space as it needs, no more. So, one element at a time. Contrast this with the method in Sun's Java implementation of ArrayList , which allocates enough space so that every resizing won't need to happen on every assignment above the initial bound. Obviously since Matlab isn't open source there's no way to tell 100% what they do, but is there a

I'm trying to find the fft of a dynamically allocated array. The input array is copied from host to device using cudaMemcpy2D . Then the fft is taken (cufftExecR2C) and the results are copied back from device to host. So my initial problem was how to use the pitch information in the fft. Then I found an answer here - CUFFT: How to calculate fft of pitched pointer? But unfortunately it doesn't work. The results I get are garbage values. Given below is my code. #define NRANK 2 #define BATCH 10 #include "cuda_runtime.h" #include "device_launch_parameters.h" #include <cufft.h> #include <stdio.h>