MATLAB: Concatenating certain columns of a (numeric) matrix. The id of columns of interest stored in a numeric array. Also some columns are selected more than once.

Question

I have a numeric matrix A. I want to generate matrix B (with the same size as A) from certain columns of matrix A. Columns of interest are specified in an array and some columns in B are repeated more than once.

Answer 1

K = rand(10) ;
L = rand(10) ;
col = [1 3 7 10] ;   % columns to be replaced 
L(:,col) = K(:,col) ;