Daniel@0: #include <stdio.h>
Daniel@0: #include "mex.h"
Daniel@0: 
Daniel@0: /*
Daniel@0: out = colop(M, v)
Daniel@0: 
Daniel@0: Apply binary operator to a vector v and to each column of M in turn
Daniel@0: to produce a matrix the same size as M.
Daniel@0: 
Daniel@0: This is equivalent to
Daniel@0: 
Daniel@0: out = zeros(size(M));
Daniel@0: for col=1:size(M,2)
Daniel@0:   out(:,col) = op(M(:,col), v);
Daniel@0: end
Daniel@0: 
Daniel@0: The code needs to be modified for each different operator 'op'.
Daniel@0: eg op = '.*'
Daniel@0: 
Daniel@0: In vectorized form:
Daniel@0: 
Daniel@0: out = M .* repmat(v(:), 1, size(M,2))
Daniel@0: 
Daniel@0: (This function was formerly called repmat_and_mult.c)
Daniel@0: 
Daniel@0: */
Daniel@0: 
Daniel@0: /* M(i,j) = M(i + nrows*j) since Matlab uses Fortran layout. */
Daniel@0: 
Daniel@0:  
Daniel@0: #define INMAT(i,j) M[(i)+nrows*(j)]
Daniel@0: #define OUTMAT(i,j) out[(i)+nrows*(j)]
Daniel@0: 
Daniel@0: void mexFunction(
Daniel@0:                  int nlhs,       mxArray *plhs[],
Daniel@0:                  int nrhs, const mxArray *prhs[]
Daniel@0: 		 )
Daniel@0: {
Daniel@0:   double *out, *M, *v;
Daniel@0:   int nrows, ncols, r, c;
Daniel@0:   
Daniel@0:   /* read the input args */
Daniel@0:   M = mxGetPr(prhs[0]);
Daniel@0:   nrows = mxGetM(prhs[0]);
Daniel@0:   ncols = mxGetN(prhs[0]);
Daniel@0: 
Daniel@0:   v = mxGetPr(prhs[1]);
Daniel@0: 
Daniel@0:   plhs[0] = mxCreateDoubleMatrix(nrows, ncols, mxREAL);
Daniel@0:   out = mxGetPr(plhs[0]); 
Daniel@0: 
Daniel@0:   for (c=0; c < ncols; c++) {
Daniel@0:     for (r=0; r < nrows; r++) {
Daniel@0:       OUTMAT(r,c) = INMAT(r,c) * v[r]; 
Daniel@0:       /* printf("r=%d, c=%d, M=%f, v=%f\n", r, c, INMAT(r,c), v[r]);  */
Daniel@0:     }
Daniel@0:   }
Daniel@0: 
Daniel@0: }
Daniel@0: 
Daniel@0: 
Daniel@0: