% COLSPACE(A)   Returns a basis for the column space of A
%   This is a sample MATLAB .m file that discards linearly
%   dependent columns from the matrix A.
%   This is a demo file for Math 63.

function B = colspace(A)

B=[];
for i=1:size(A,2)
  x = A(:,i)
  if rank([B x]) > rank(B)
    B = [B x];
  end
end