MATLAB: How to convert for loop statement to matrix operation

Question

Hi, I am very new to using Matlab. Due to the processing issue, I would like to convert for-loop statement to matrix calculation to accelerate processing time.

For example,

    [u v] = size(input_img);
    for i=1:u
        for j=1:v
            if (input_img(i,j) == 0)
                temp(i,j)=0;
            end
        end
    end

Thank you.

Answer 1

Assuming the matrix sizes are compatible, using logical indexing:

temp( input_img == 0 ) = 0;