/* $Id: is.h,v 1.28 1996/08/04 23:14:42 bsmith Exp bsmith $ */

/*
      An index set is a genralization of a subset of integers. They are used
   for defining scatters and gathers.
*/
#if !defined(__IS_PACKAGE)
#define __IS_PACKAGE
#include "petsc.h"

typedef enum {IS_SEQ=0, IS_STRIDE_SEQ=1, IS_BLOCK_SEQ = 2} ISType;

#define IS_COOKIE PETSC_COOKIE+2

typedef struct _IS* IS;

extern int   ISCreateSeq(MPI_Comm,int,int *,IS *);
extern int   ISCreateBlockSeq(MPI_Comm,int,int,int *,IS *);
extern int   ISCreateStrideSeq(MPI_Comm,int,int,int,IS *);

extern int   ISDestroy(IS);

extern int   ISSetPermutation(IS);
extern int   ISPermutation(IS,PetscTruth*); 
extern int   ISSetIdentity(IS);
extern int   ISIdentity(IS,PetscTruth*);

extern int   ISGetIndices(IS,int **);
extern int   ISRestoreIndices(IS,int **);
extern int   ISGetSize(IS,int *);
extern int   ISInvertPermutation(IS,IS*);
extern int   ISView(IS,Viewer);
extern int   ISEqual(IS, IS, PetscTruth *);
extern int   ISSort(IS);
extern int   ISSorted(IS, PetscTruth *);

extern int   ISBlockGetIndices(IS,int **);
extern int   ISBlockRestoreIndices(IS,int **);
extern int   ISBlockGetBlockSize(IS,int **);

extern int   ISStrideGetInfo(IS,int *,int*);

#endif