Hi Shayne, you seem to dynamically changing the size of the red, blue and green arrays in your loop which could cause errors due to invalid indexing and also affect performance. The use of for loop also greatly slows down performance, a vectorized approach would be more useful here using the & operator. Here is a suggestion for an alternate workflow to achieve the same goal:
%Set alpha, beta and gammas to some random array of length 7000000
alpha = randi([0,4],7000000,1);
beta = randi([0,4],7000000,1);
gammas = randi([0,4],7000000,1);
%Initialize red, green and blue
red = alpha;
green = beta;
blue = gammas;
%Check computational speed
tic
%Determine logical indices where alpha, beta and gamma are zero
ind1 = (alpha == 0);
ind2 = (beta == 0);
ind3 = (gammas == 0);
%Find logical indices where all three are zero
ind = ind1 & ind2 & ind3;
%Set those values of the colors to []
red(ind) = [];
blue(ind) = [];
green(ind) = [];
toc
Please note that here I am assuming it was your intention to have nonzero values for red,blue and green when alpha, beta and gamma were not all zero. To implement the exact logic as in your original code snippet, you need to make minor modifications. However, the essence is still the same - use a vectorized approach with logical indexing!
