Creating a certain array

Hi I want to create a 10 by 10 array and replace its values. If the said value is at 1,1 / 3,1 / etc. where combination of 2 values of its rows and columns make an even number I want it to be 10 and if its 2,1 / 1,4 etc. I want it to be 20. Any idea how I can achieve that? I guess i should check the combination of row and column numbers for divisibility by 2 but I couldn't find how.

Answer 1

[Jan]

v = rem(1:10, 2);
M = 10 + 10 * (v ~= v.')

Or with linear indexing:

M = 10 * ones(9);
M(2:numel(M)) = 20;

The 1st method works with all sizes of the matrox, while the 2nd method needs an odd number of rows, so it does not work with n=10.