/*
Routines to set ST methods and options.
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SLEPc - Scalable Library for Eigenvalue Problem Computations
Copyright (c) 2002-2007, Universidad Politecnica de Valencia, Spain
This file is part of SLEPc. See the README file for conditions of use
and additional information.
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*/
#include "private/stimpl.h" /*I "slepcst.h" I*/
#include "petscsys.h"
/*
Contains the list of registered ST routines
*/
PetscFList STList = 0;
#undef __FUNCT__
#define __FUNCT__ "STSetType"
/*@C
STSetType - Builds ST for a particular spectral transformation.
Collective on ST
Input Parameter:
+ st - the spectral transformation context.
- type - a known type
Options Database Key:
. -st_type <type> - Sets ST type
Use -help for a list of available transformations
Notes:
See "slepc/include/slepcst.h" for available transformations
Normally, it is best to use the EPSSetFromOptions() command and
then set the ST type from the options database rather than by using
this routine. Using the options database provides the user with
maximum flexibility in evaluating the many different transformations.
Level: intermediate
.seealso: EPSSetType()
@*/
PetscErrorCode STSetType(ST st,const STType type)
{
PetscErrorCode ierr,(*r)(ST);
PetscTruth match;
PetscFunctionBegin;
PetscValidHeaderSpecific(st,ST_COOKIE,1);
PetscValidCharPointer(type,2);
ierr = PetscTypeCompare((PetscObject)st,type,&match);CHKERRQ(ierr);
if (match) PetscFunctionReturn(0);
if (st->ops->destroy) {ierr = (*st->ops->destroy)(st);CHKERRQ(ierr);}
ierr = PetscFListDestroy(&((PetscObject)st)->qlist);CHKERRQ(ierr);
st->data = 0;
st->setupcalled = 0;
/* Determine the STCreateXXX routine for a particular type */
ierr = PetscFListFind(STList, ((PetscObject)st)->comm, type,(void (**)(void)) &r );CHKERRQ(ierr);
if (!r) SETERRQ1(1,"Unable to find requested ST type %s",type);
ierr = PetscFree(st->data);CHKERRQ(ierr);
ierr = PetscMemzero(st->ops,sizeof(struct _STOps));CHKERRQ(ierr);
/* Call the STCreateXXX routine for this particular type */
ierr = (*r)(st);CHKERRQ(ierr);
ierr = PetscObjectChangeTypeName((PetscObject)st,type);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "STGetType"
/*@C
STGetType - Gets the ST type name (as a string) from the ST context.
Not Collective
Input Parameter:
. st - the spectral transformation context
Output Parameter:
. name - name of the spectral transformation
Level: intermediate
.seealso: STSetType()
@*/
PetscErrorCode STGetType(ST st,const STType *type)
{
PetscFunctionBegin;
PetscValidHeaderSpecific(st,ST_COOKIE,1);
PetscValidPointer(type,2);
*type = ((PetscObject)st)->type_name;
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "STSetFromOptions"
/*@
STSetFromOptions - Sets ST options from the options database.
This routine must be called before STSetUp() if the user is to be
allowed to set the type of transformation.
Collective on ST
Input Parameter:
. st - the spectral transformation context
Level: beginner
.seealso:
@*/
PetscErrorCode STSetFromOptions(ST st)
{
PetscErrorCode ierr;
PetscInt i;
char type[256];
PetscTruth flg;
const char *mode_list[3] = { "copy", "inplace", "shell" };
const char *structure_list[3] = { "same", "different", "subset" };
PC pc;
PetscFunctionBegin;
PetscValidHeaderSpecific(st,ST_COOKIE,1);
ierr = PetscOptionsBegin(((PetscObject)st)->comm,((PetscObject)st)->prefix,"Spectral Transformation (ST) Options","ST");CHKERRQ(ierr);
ierr = PetscOptionsList("-st_type","Spectral Transformation type","STSetType",STList,(char*)(((PetscObject)st)->type_name?((PetscObject)st)->type_name:STSHIFT),type,256,&flg);CHKERRQ(ierr);
if (flg) {
ierr = STSetType(st,type);CHKERRQ(ierr);
}
/*
Set the type if it was never set.
*/
if (!((PetscObject)st)->type_name) {
ierr = STSetType(st,STSHIFT);CHKERRQ(ierr);
}
ierr = PetscOptionsScalar("-st_shift","Value of the shift","STSetShift",st->sigma,&st->sigma,PETSC_NULL); CHKERRQ(ierr);
ierr = PetscOptionsEList("-st_matmode", "Shift matrix mode","STSetMatMode",mode_list,3,mode_list[st->shift_matrix],&i,&flg);CHKERRQ(ierr);
if (flg) { st->shift_matrix = (STMatMode)i; }
ierr = PetscOptionsEList("-st_matstructure", "Shift nonzero pattern","STSetMatStructure",structure_list,3,structure_list[st->str],&i,&flg);CHKERRQ(ierr);
if (flg) { st->str = (MatStructure)i; }
if (st->ops->setfromoptions) {
ierr = (*st->ops->setfromoptions)(st);CHKERRQ(ierr);
}
ierr = PetscOptionsEnd();CHKERRQ(ierr);
if (st->ksp) {
if (st->shift_matrix == STMATMODE_SHELL) {
/* if shift_mat is set then the default preconditioner is ILU,
otherwise set Jacobi as the default */
ierr = KSPGetPC(st->ksp,&pc); CHKERRQ(ierr);
ierr = PCSetType(pc,PCJACOBI);CHKERRQ(ierr);
}
ierr = KSPSetFromOptions(st->ksp);CHKERRQ(ierr);
}
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "STSetMatStructure"
/*@
STSetMatStructure - Sets an internal MatStructure attribute to
indicate which is the relation of the sparsity pattern of the two matrices
A and B constituting the generalized eigenvalue problem. This function
has no effect in the case of standard eigenproblems.
Collective on ST
Input Parameters:
+ st - the spectral transformation context
- str - either SAME_NONZERO_PATTERN, DIFFERENT_NONZERO_PATTERN or
SUBSET_NONZERO_PATTERN
Options Database Key:
. -st_matstructure <str> - Indicates the structure flag, where <str> is one
of 'same' (A and B have the same nonzero pattern), 'different' (A
and B have different nonzero pattern) or 'subset' (B's nonzero
pattern is a subset of A's).
Note:
By default, the sparsity patterns are assumed to be different. If the
patterns are equal or a subset then it is recommended to set this attribute
for efficiency reasons (in particular, for internal MatAXPY() operations).
Level: advanced
.seealso: STSetOperators(), MatAXPY()
@*/
PetscErrorCode STSetMatStructure(ST st,MatStructure str)
{
PetscFunctionBegin;
PetscValidHeaderSpecific(st,ST_COOKIE,1);
switch (str) {
case SAME_NONZERO_PATTERN:
case DIFFERENT_NONZERO_PATTERN:
case SUBSET_NONZERO_PATTERN:
st->str = str;
break;
default:
SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Invalid matrix structure flag");
}
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "STSetMatMode"
/*@
STSetMatMode - Sets a flag to indicate how the matrix is
being shifted in the shift-and-invert and Cayley spectral transformations.
Collective on ST
Input Parameters:
+ st - the spectral transformation context
- mode - the mode flag, one of STMATMODE_COPY,
STMATMODE_INPLACE or STMATMODE_SHELL
Options Database Key:
. -st_matmode <mode> - Indicates the mode flag, where <mode> is one of
'copy', 'inplace' or 'shell' (see explanation below).
Notes:
By default (STMATMODE_COPY), a copy of matrix A is made and then
this copy is shifted explicitly, e.g. A <- (A - s B).
With STMATMODE_INPLACE, the original matrix A is shifted at
STSetUp() and unshifted at the end of the computations. With respect to
the previous one, this mode avoids a copy of matrix A. However, a
backdraw is that the recovered matrix might be slightly different
from the original one (due to roundoff).
With STMATMODE_SHELL, the solver works with an implicit shell
matrix that represents the shifted matrix. This mode is the most efficient
in creating the shifted matrix but it places serious limitations to the
linear solves performed in each iteration of the eigensolver (typically,
only interative solvers with Jacobi preconditioning can be used).
In the case of generalized problems, in the two first modes the matrix
A - s B has to be computed explicitly. The efficiency of this computation
can be controlled with STSetMatStructure().
Level: intermediate
.seealso: STSetOperators(), STSetMatStructure(), STGetMatMode(), STMatMode
@*/
PetscErrorCode STSetMatMode(ST st,STMatMode mode)
{
PetscFunctionBegin;
PetscValidHeaderSpecific(st,ST_COOKIE,1);
st->shift_matrix = mode;
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "STGetMatMode"
/*@C
STGetMatMode - Gets a flag that indicates how the matrix is being
shifted in the shift-and-invert and Cayley spectral transformations.
Collective on ST
Input Parameter:
. st - the spectral transformation context
Output Parameter:
. mode - the mode flag
Level: intermediate
.seealso: STSetMatMode(), STMatMode
@*/
PetscErrorCode STGetMatMode(ST st,STMatMode *mode)
{
PetscFunctionBegin;
PetscValidHeaderSpecific(st,ST_COOKIE,1);
*mode = st->shift_matrix;
PetscFunctionReturn(0);
}