How to apply arrayfun on a 3D matrix?

22 views (last 30 days)
I have the following matrix:
size(A) = [64 64 1000];
I'd like to apply the following function on each frame, along the 3rd dimension.
lasca_func = @(x)(mean2(x)/std2(x));
How can I do this via arrayfun, and not through for-loop?
Thanks in advance!
  1 Comment
Adam on 25 Jul 2017
I don't think arrayfun can be used for that - it takes the array values in turn as linear indices so the structure of the array is not preserved and the function will be applied per element for the whole 64*64*1000.

Sign in to comment.

Accepted Answer

Stephen23 on 25 Jul 2017
Edited: Stephen23 on 25 Jul 2017
"How can I do this via arrayfun, and not through for-loop?"
You can't, because arrayfun operates on each element of an array. You cannot tell it to operate along specific dimensions of an array. An alternative would be to split the array into a cell array and then call cellfun, but this would be slower than using a preallocated loop.
Unless you have a gpuArray the simplest solution is to use mean and std, and specify the dimension:
>> A = rand(64,64,1000);
>> Z = mean(A,3)./std(A,0,3);
>> size(Z)
ans =
64 64

Sign in to comment.

More Answers (0)

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!