They don't work because you're wanting a specialized operation. Here is a way that works:
A = [4 8 6 1 2 3 1 9 4 5]; % Input data array
output = zeros(1, length(A));
windowLength = 3; % Window length for the moving maximum.
for k = 1 : length(A) - windowLength + 1
thisWindow = A(k : k + windowLength - 1)
windowMax = max(thisWindow)
for k2 = k : k + windowLength - 1
if thisWindow(k2-k+1) == windowMax
output(k2) = A(k2);
end
end
end
output % Show in command window.
