int main()
{
std::cout << std::boolalpha;
// Not antisymetric
std::cout << mycomp(2, -3) << '\n';
std::cout << mycomp(-3, 2) << '\n';
// Not transitive
std::cout << mycomp(-2, -2) << '\n';
std::cout << mycomp(-3, 2) << '\n';
std::cout << mycomp(2, 2) << '\n';
}
void mexFunction(
int nlhs, mxArray *plhs[],
int nrhs, const mxArray *prhs[]
)
{
mwSize n, k, col, nskip, lastcol, *ss_ndxs;
double *map, *scl, lastnorm;
bool first;
n = mxGetN( prhs[0] );
ss_ir = mxGetIr( prhs[0] );
ss_jc = mxGetJc( prhs[0] );
ss_pr = mxGetPr( prhs[0] );
ss_mode = nrhs < 2 ? FULL_COMPRESS : (int)mxGetScalar( prhs[1] );
nskip = nrhs < 3 ? 0 : (int)mxGetScalar(prhs[2]);
ss_ndxs = mxCalloc( n, sizeof(mwSize) );
ss_temp = mxCalloc( n, sizeof(mwSize) );
/*
* Sort the column indices
*/
for ( col = 0 ; col != n ; ++col )
ss_ndxs[col] = col;
if ( nskip < n )
merge_sort( ss_ndxs + nskip, ss_ndxs + n );
/*
* Determine which rows are unique, and which are scales of another row
*/
plhs[0] = mxCreateDoubleMatrix( (mwSize)1, n, mxREAL );
plhs[1] = mxCreateDoubleMatrix( (mwSize)1, n, mxREAL );
if ( plhs[0] == 0 || plhs[1] == 0 )
mexErrMsgTxt( "Unable to allocate output arguments" );
map = mxGetPr( plhs[0] );
scl = mxGetPr( plhs[1] );
first = true;
lastnorm = 0.0;
for ( k = 0 ; k < n ; ++k ) {
col = ss_ndxs[k];
if ( col < nskip ) {
map[col] = col + 1;
scl[col] = 1.0;
} else if ( ss_jc[col] == ss_jc[col+1] ) {
map[col] = col + 1;
scl[col] = 0;
} else if ( first || mycomp( lastcol, col ) != 0 ) {
lastcol = col;
lastnorm = ss_pr[ss_jc[col]];
map[col] = lastcol + 1;
scl[col] = 1.0;
first = false;
} else {
map[col] = lastcol + 1;
scl[col] = ss_pr[ss_jc[col]] / lastnorm;
}
}
}
void merge( mwSize *nb, mwSize *nm, mwSize *ne )
{
mwSize *i = nb, *j = nm, *t = ss_temp;
for ( ;; )
if ( mycomp( *i, *j ) <= 0 ) {
*t++ = *i++;
if ( i == nm ) {
while ( j != ne )
*t++ = *j++;
break;
}
} else {
*t++ = *j++;
if ( j == ne ) {
while ( i != nm )
*t++ = *i++;
break;
}
}
for ( i = nb, t = ss_temp ; i != ne ; *i++ = *t++ );
}
