I want to make sure I'm correctly understanding what you're looking to end up with. Based on the first two for loops you're going to run through your Block from left to right, top to bottom, allowing you to examine all elements of Block individually.
for k=1:size(Block,1) % Selects each row of Block
for r=1:size(Block,2) % Selects each column of Block
if Block(k,r)==1 && Type(k,r)==6 % Status check to look for block 1, type
% 6 elements. Is type also 399x3?
b=0; % Initialization, I'm assuming
for m=1:size(RTc,1) % How does RTc get limited by your if statement.
% Currently these loops will only run when Block is 1
% and Type is 6, but there is no further restriction
% on the values of RTc, so all values of RTc will be
% evaluated (from what I can currently see of your
% code).
for n=1:size(RTc,2)
M_type6=mean(RTc,'omitnan');
b=b+1;
end
end
end
end
end
