gpuArray loop indexing question

Hi guys,

For those familiar with gpuArray and arrayfun, is there a way to perform the following operation?

The general form is:

[a ,b]=find(phi)
PHI=zeros(---)

    for n=1:numel(a)
        PHI(a(n),b(n))=phi(a(n),b(n));
    end

Much thanks in advance!

Answer 1

[Edric Ellis]

I think part of your underlying problem must be missing here, since in this case, PHI and phi end up the same. Anyway, you could use logical indexing for this.

    % generate 'phi' as a random matrix
    phi = gpuArray.rand(100);
    % set all elements <0.9 to zero
    phi(phi < 0.9) = 0;
    % pre-allocate PHI
    PHI = gpuArray.zeros(size(phi));
    % Instead of FIND, use 'logical' to get the places
    % where phi is non-zero
    match = logical(phi);
    % Use logical indexing to copy the elements
    PHI(match) = phi(match);