matrix operation make matrix

i have matrix A = rand(64,4), i want to process them to make new matrix where B = (K-A(:,1))*2 . k is multiply every 8, example A=1:8:64 so K=1 , A=2:8:64 so K=2 , A=3:8:64 so K=3, A=4:8:64 so K=4, A=5:8:64 so K=5, A=6:8:64 so K=2, A=7:8:64 so K=2, A=8:8:64 so K=2. how to find B ?

Answer 1

[Andrei Bobrov]

A = rand(64,4);

K = reshape([(1:5)';2;2;2]*ones(1,8),[],1);
B = 2*(K - A(:,1));