binning a matrix down

i have 2 different matrices, one thats 3220x6440 and the other is 1440x2880 and i would like to directly compare them and so i need both matrices to be 1440x2880 but im not sure how to bin the 3220x6440 matrix to make it a 1440x2880 matrix as the multiple is not an integar.

Answer 1

[Walter Roberson]

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