matthiasm@8: function M = assign_cols(cols, vals, M)
matthiasm@8: % ASSIGN_COLS Assign values to columns of a matrix
matthiasm@8: % function M = assign_cols(M, cols, vals, M)
matthiasm@8: %
matthiasm@8: % Example:
matthiasm@8: % M = assign_cols(data, ones(1,N))
matthiasm@8: % will construct a 1-of-K encoding of the data, where K=ncols=max(data) and N=nrows=length(data)
matthiasm@8: %
matthiasm@8: % Example:
matthiasm@8: % M = zeros(3,2);
matthiasm@8: % M = assign_cols([1 2 1], [10 20 30], M)
matthiasm@8: % is equivalent to
matthiasm@8: % M(1, 1) = 10
matthiasm@8: % M(2, 2) = 20
matthiasm@8: % M(3, 1) = 30
matthiasm@8: %
matthiasm@8: 
matthiasm@8: if nargin < 3
matthiasm@8:   nr = length(cols);
matthiasm@8:   nc = max(cols);
matthiasm@8:   M = zeros(nr, nc);
matthiasm@8: else
matthiasm@8:   [nr nc] = size(M);
matthiasm@8: end
matthiasm@8: 
matthiasm@8: if 0
matthiasm@8: for r=1:nr
matthiasm@8:   M(r, cols(r)) = vals(r);
matthiasm@8: end
matthiasm@8: end
matthiasm@8: 
matthiasm@8: if 1
matthiasm@8: rows = 1:nr;
matthiasm@8: ndx = subv2ind([nr nc], [rows(:) cols(:)]);
matthiasm@8: M(ndx) = vals;
matthiasm@8: end