/*
BVOrthogonalizeMGS1 - Compute one step of Modified Gram-Schmidt
*/
static PetscErrorCode BVOrthogonalizeMGS1(BV bv,PetscInt k,Vec v,PetscBool *which,PetscScalar *H)
{
PetscErrorCode ierr;
PetscInt i;
PetscScalar dot;
Vec vi,z;
PetscFunctionBegin;
z = v;
for (i=-bv->nc;i<k;i++) {
if (which && i>=0 && !which[i]) continue;
ierr = BVGetColumn(bv,i,&vi);CHKERRQ(ierr);
/* h_i = ( v, v_i ) */
if (bv->matrix) {
ierr = BV_IPMatMult(bv,v);CHKERRQ(ierr);
z = bv->Bx;
}
ierr = VecDot(z,vi,&dot);CHKERRQ(ierr);
/* v <- v - h_i v_i */
if (bv->indef) dot /= bv->omega[bv->nc+i];
ierr = VecAXPY(v,-dot,vi);CHKERRQ(ierr);
if (bv->indef) dot *= bv->omega[bv->nc+i];
if (H) H[bv->nc+i] += dot;
ierr = BVRestoreColumn(bv,i,&vi);CHKERRQ(ierr);
}
PetscFunctionReturn(0);
}
PetscErrorCode BVDotVec_Contiguous(BV X,Vec y,PetscScalar *m)
{
PetscErrorCode ierr;
BV_CONTIGUOUS *x = (BV_CONTIGUOUS*)X->data;
PetscScalar *py;
Vec z = y;
PetscFunctionBegin;
if (X->matrix) {
ierr = BV_IPMatMult(X,y);CHKERRQ(ierr);
z = X->Bx;
}
ierr = VecGetArray(z,&py);CHKERRQ(ierr);
ierr = BVDotVec_BLAS_Private(X,X->n,X->k-X->l,x->array+(X->nc+X->l)*X->n,py,m,x->mpi);CHKERRQ(ierr);
ierr = VecRestoreArray(z,&py);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
PetscErrorCode BVDotVec_Mat(BV X,Vec y,PetscScalar *m)
{
PetscErrorCode ierr;
BV_MAT *x = (BV_MAT*)X->data;
PetscScalar *px,*py;
Vec z = y;
PetscFunctionBegin;
if (X->matrix) {
ierr = BV_IPMatMult(X,y);CHKERRQ(ierr);
z = X->Bx;
}
ierr = MatDenseGetArray(x->A,&px);CHKERRQ(ierr);
ierr = VecGetArray(z,&py);CHKERRQ(ierr);
ierr = BVDotVec_BLAS_Private(X,X->n,X->k-X->l,px+(X->nc+X->l)*X->n,py,m,x->mpi);CHKERRQ(ierr);
ierr = VecRestoreArray(z,&py);CHKERRQ(ierr);
ierr = MatDenseRestoreArray(x->A,&px);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
