/* ************************************************************
PROCEDURE bwprodform - Solves (PROD_j L(pj,betaj))' * yNEW = yOLD.
INPUT
p - nonzeros of sparse m x n matrix P. Has xsuper(j+1) nonzeros in
column j.
xsuper - xsuper(j+1) is number of nonzeros in p(:,j).
perm - lists pivot order for columns where ordered(j)==1.
ordered - ordered[j]==1 iff p(:,j) and beta(L:,j) have been reordered;
the original row numbers are in perm(:,j).
n - number of columns in p, beta.
UPDATED
y - length m vector. On input, the rhs. On output the solution to
(PROD_j L(pj,betaj))' * yNEW = yOLD.
************************************************************ */
void bwprodform(double *y, const mwIndex *xsuper, const mwIndex *perm,
const double *p, const double *beta, const mwIndex *betajc,
const char *ordered, const mwIndex n, mwIndex pnnz,
mwIndex permnnz)
{
mwIndex k,nk, mk;
/* ------------------------------------------------------------
Backward solve L(pk,betak) * yNEXT = yPREV for k=n-1:-1:0.
------------------------------------------------------------ */
for(k = n; k > 0; k--){
mk = xsuper[k];
nk = betajc[k] - betajc[k-1];
pnnz -= mk;
if(ordered[k-1]){
permnnz -= mk;
bwipr1o(y, perm+permnnz, p+pnnz, beta+betajc[k-1], mk, nk);
}
else
bwipr1(y, p+pnnz, beta+betajc[k-1], mk, nk);
}
mxAssert(pnnz == 0,"");
mxAssert(permnnz == 0 || permnnz == 1,"");
}
/* ************************************************************
PROCEDURE bwprodform - Solves (PROD_j L(pj,betaj))' * yNEW = yOLD.
INPUT
p - nonzeros of sparse m x n matrix P. Has xsuper(j+1) nonzeros in
column j.
xsuper - xsuper(j+1) is number of nonzeros in p(:,j).
perm - lists pivot order for columns where ordered(j)==1.
ordered - ordered[j]==1 iff p(:,j) and beta(L:,j) have been reordered;
the original row numbers are in perm(:,j).
n - number of columns in p, beta.
UPDATED
y - length m vector. On input, the rhs. On output the solution to
(PROD_j L(pj,betaj))' * yNEW = yOLD.
************************************************************ */
void bwprodform(double *y, const int *xsuper, const int *perm,
const double *p, const double *beta, const int *betajc,
const char *ordered, const int n, int pnnz,
int permnnz)
{
int k,nk, mk;
/* ------------------------------------------------------------
Backward solve L(pk,betak) * yNEXT = yPREV for k=n-1:-1:0.
------------------------------------------------------------ */
for(k = n-1; k >= 0; k--){
mk = xsuper[k+1];
nk = betajc[k+1] - betajc[k];
pnnz -= mk;
if(ordered[k]){
permnnz -= mk;
bwipr1o(y, perm+permnnz, p+pnnz, beta+betajc[k], mk, nk);
}
else
bwipr1(y, p+pnnz, beta+betajc[k], mk, nk);
}
mxAssert(pnnz == 0,"");
mxAssert(permnnz == 0 || permnnz == 1,"");
}
