Mercurial > hg > camir-aes2014
annotate toolboxes/FullBNT-1.0.7/KPMtools/colmult.c @ 0:e9a9cd732c1e tip
first hg version after svn
| author | wolffd |
|---|---|
| date | Tue, 10 Feb 2015 15:05:51 +0000 |
| parents | |
| children |
| rev | line source |
|---|---|
| wolffd@0 | 1 #include <stdio.h> |
| wolffd@0 | 2 #include "mex.h" |
| wolffd@0 | 3 |
| wolffd@0 | 4 /* |
| wolffd@0 | 5 out = colop(M, v) |
| wolffd@0 | 6 |
| wolffd@0 | 7 Apply binary operator to a vector v and to each column of M in turn |
| wolffd@0 | 8 to produce a matrix the same size as M. |
| wolffd@0 | 9 |
| wolffd@0 | 10 This is equivalent to |
| wolffd@0 | 11 |
| wolffd@0 | 12 out = zeros(size(M)); |
| wolffd@0 | 13 for col=1:size(M,2) |
| wolffd@0 | 14 out(:,col) = op(M(:,col), v); |
| wolffd@0 | 15 end |
| wolffd@0 | 16 |
| wolffd@0 | 17 The code needs to be modified for each different operator 'op'. |
| wolffd@0 | 18 eg op = '.*' |
| wolffd@0 | 19 |
| wolffd@0 | 20 In vectorized form: |
| wolffd@0 | 21 |
| wolffd@0 | 22 out = M .* repmat(v(:), 1, size(M,2)) |
| wolffd@0 | 23 |
| wolffd@0 | 24 (This function was formerly called repmat_and_mult.c) |
| wolffd@0 | 25 |
| wolffd@0 | 26 */ |
| wolffd@0 | 27 |
| wolffd@0 | 28 /* M(i,j) = M(i + nrows*j) since Matlab uses Fortran layout. */ |
| wolffd@0 | 29 |
| wolffd@0 | 30 |
| wolffd@0 | 31 #define INMAT(i,j) M[(i)+nrows*(j)] |
| wolffd@0 | 32 #define OUTMAT(i,j) out[(i)+nrows*(j)] |
| wolffd@0 | 33 |
| wolffd@0 | 34 void mexFunction( |
| wolffd@0 | 35 int nlhs, mxArray *plhs[], |
| wolffd@0 | 36 int nrhs, const mxArray *prhs[] |
| wolffd@0 | 37 ) |
| wolffd@0 | 38 { |
| wolffd@0 | 39 double *out, *M, *v; |
| wolffd@0 | 40 int nrows, ncols, r, c; |
| wolffd@0 | 41 |
| wolffd@0 | 42 /* read the input args */ |
| wolffd@0 | 43 M = mxGetPr(prhs[0]); |
| wolffd@0 | 44 nrows = mxGetM(prhs[0]); |
| wolffd@0 | 45 ncols = mxGetN(prhs[0]); |
| wolffd@0 | 46 |
| wolffd@0 | 47 v = mxGetPr(prhs[1]); |
| wolffd@0 | 48 |
| wolffd@0 | 49 plhs[0] = mxCreateDoubleMatrix(nrows, ncols, mxREAL); |
| wolffd@0 | 50 out = mxGetPr(plhs[0]); |
| wolffd@0 | 51 |
| wolffd@0 | 52 for (c=0; c < ncols; c++) { |
| wolffd@0 | 53 for (r=0; r < nrows; r++) { |
| wolffd@0 | 54 OUTMAT(r,c) = INMAT(r,c) * v[r]; |
| wolffd@0 | 55 /* printf("r=%d, c=%d, M=%f, v=%f\n", r, c, INMAT(r,c), v[r]); */ |
| wolffd@0 | 56 } |
| wolffd@0 | 57 } |
| wolffd@0 | 58 |
| wolffd@0 | 59 } |
| wolffd@0 | 60 |
| wolffd@0 | 61 |
| wolffd@0 | 62 |