Hello,

I have for example,

`m = randi(9, [10, 12]);otuputRow=1;for row = 1 : size(m, 2)theSums(:, otuputRow) = sum(m(:,row:row+2:end),2);otuputRow = otuputRow + 1;end`

but matlab show this error: Unable to perform assignment because the size of the left side is 3-by-1 and the size of the right side is 10-by-1.

I want sum columns every 3 columns (but element by element), so, the matrix resultant should be of 10x(12/3), this is a example but really the number of steps for sum can change (every 4, or every 5 columns…)

Thanks!!

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