/* combination/gsl_combination.h

 * based on permutation/gsl_permutation.h by Brian Gough

 * 

 * Copyright (C) 2001 Szymon Jaroszewicz

 * 

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 3 of the License, or (at

 * your option) any later version.

 * 

 * This program is distributed in the hope that it will be useful, but

 * WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * General Public License for more details.

 * 

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

 */

#ifndef __GSL_COMBINATION_H__

#define __GSL_COMBINATION_H__

#include <stdlib.h>

#include <gsl/gsl_errno.h>

#include <gsl/gsl_types.h>

#include <gsl/gsl_inline.h>

#include <gsl/gsl_check_range.h>

#undef __BEGIN_DECLS

#undef __END_DECLS

#ifdef __cplusplus

# define __BEGIN_DECLS extern "C" {

# define __END_DECLS }

#else

# define __BEGIN_DECLS /* empty */

# define __END_DECLS /* empty */

#endif

__BEGIN_DECLS

struct gsl_combination_struct

{

  size_t n;

  size_t k;

  size_t *data;

};

typedef struct gsl_combination_struct gsl_combination;

gsl_combination *gsl_combination_alloc (const size_t n, const size_t k);

gsl_combination *gsl_combination_calloc (const size_t n, const size_t k);

void gsl_combination_init_first (gsl_combination * c);

void gsl_combination_init_last (gsl_combination * c);

void gsl_combination_free (gsl_combination * c);

int gsl_combination_memcpy (gsl_combination * dest, const gsl_combination * src); 

int gsl_combination_fread (FILE * stream, gsl_combination * c);

int gsl_combination_fwrite (FILE * stream, const gsl_combination * c);

int gsl_combination_fscanf (FILE * stream, gsl_combination * c);

int gsl_combination_fprintf (FILE * stream, const gsl_combination * c, const char *format);

size_t gsl_combination_n (const gsl_combination * c);

size_t gsl_combination_k (const gsl_combination * c);

size_t * gsl_combination_data (const gsl_combination * c);

int gsl_combination_valid (gsl_combination * c);

int gsl_combination_next (gsl_combination * c);

int gsl_combination_prev (gsl_combination * c);

INLINE_DECL size_t gsl_combination_get (const gsl_combination * c, const size_t i);

#ifdef HAVE_INLINE

INLINE_FUN

size_t

gsl_combination_get (const gsl_combination * c, const size_t i)

{

#if GSL_RANGE_CHECK

  if (GSL_RANGE_COND(i >= c->k)) /* size_t is unsigned, can't be negative */

    {

      GSL_ERROR_VAL ("index out of range", GSL_EINVAL, 0);

    }

#endif

  return c->data[i];

}

#endif /* HAVE_INLINE */

__END_DECLS

#endif /* __GSL_COMBINATION_H__ */