# How to make a matrix with the entries being the number of even indices of that entry?

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Joshua Balfour on 13 Sep 2019
Commented: Walter Roberson on 16 Sep 2019
I need to make a 12x12 matrix with the entries being the number of even indices of the entry.
So 1,1 would be 0, 1,2 would be 1 and 2,2 would equal 2.
The task is specifically using for loops or the meshgrid function.
Any help would be appreciated.
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Joshua Balfour on 16 Sep 2019
Edited: Joshua Balfour on 16 Sep 2019
mat = zeros(12,12);
x = 1:12;
y = 1:12;
[X, Y] = meshgrid(x,y);
a = mod(X,2);
b = mod(Y,2);
matrix = a + b;
This gives a matrix of:
matrix =
2 1 2 1 2 1 2 1 2 1 2 1
1 0 1 0 1 0 1 0 1 0 1 0
2 1 2 1 2 1 2 1 2 1 2 1
1 0 1 0 1 0 1 0 1 0 1 0
2 1 2 1 2 1 2 1 2 1 2 1
1 0 1 0 1 0 1 0 1 0 1 0
2 1 2 1 2 1 2 1 2 1 2 1
1 0 1 0 1 0 1 0 1 0 1 0
2 1 2 1 2 1 2 1 2 1 2 1
1 0 1 0 1 0 1 0 1 0 1 0
2 1 2 1 2 1 2 1 2 1 2 1
1 0 1 0 1 0 1 0 1 0 1 0
but this gives the odd indices, I want the even ones.
Walter Roberson on 16 Sep 2019
1-mod(value,2)

Jos (10584) on 13 Sep 2019
help meshgrid
help rem