text: /* -*- mode: C -*-  */
  /*
     IGraph library.
     Copyright (C) 2009-2012  Gabor Csardi <csardi.gabor@gmail.com>
     334 Harvard street, Cambridge, MA 02139 USA
  
     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 2 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 IGRAPH_NONGRAPH_H
  #define IGRAPH_NONGRAPH_H
  
  #include "igraph_decls.h"
  #include "igraph_constants.h"
  #include "igraph_matrix.h"
  #include "igraph_types.h"
  #include "igraph_vector.h"
  
  __BEGIN_DECLS
  
  /* -------------------------------------------------- */
  /* Other, not graph related                           */
  /* -------------------------------------------------- */
  
  /**
   * \struct igraph_plfit_result_t
   * \brief Result of fitting a power-law distribution to a vector
   *
   * This data structure contains the result of \ref igraph_power_law_fit(),
   * which tries to fit a power-law distribution to a vector of numbers. The
   * structure contains the following members:
   *
   * \member continuous Whether the fitted power-law distribution was continuous
   *                    or discrete.
   * \member alpha The exponent of the fitted power-law distribution.
   * \member xmin  The minimum value from which the power-law distribution was
   *               fitted. In other words, only the values larger than \c xmin
   *               were used from the input vector.
   * \member L     The log-likelihood of the fitted parameters; in other words,
   *               the probability of observing the input vector given the
   *               parameters.
   * \member D     The test statistic of a Kolmogorov-Smirnov test that compares
   *               the fitted distribution with the input vector. Smaller scores
   *               denote better fit.
   * \member p     The p-value of the Kolmogorov-Smirnov test. Small p-values
   *               (less than 0.05) indicate that the test rejected the hypothesis
   *               that the original data could have been drawn from the fitted
   *               power-law distribution.
   */
  typedef struct igraph_plfit_result_t {
      igraph_bool_t continuous;
      double alpha;
      double xmin;
      double L;
      double D;
      double p;
  } igraph_plfit_result_t;
  
  DECLDIR int igraph_running_mean(const igraph_vector_t *data, igraph_vector_t *res,
                                  igraph_integer_t binwidth);
  DECLDIR int igraph_fisher_yates_shuffle(igraph_vector_t *seq);
  DECLDIR int igraph_random_sample(igraph_vector_t *res, igraph_real_t l, igraph_real_t h,
                                   igraph_integer_t length);
  DECLDIR int igraph_convex_hull(const igraph_matrix_t *data, igraph_vector_t *resverts,
                                 igraph_matrix_t *rescoords);
  DECLDIR int igraph_zeroin(igraph_real_t *ax, igraph_real_t *bx,
                            igraph_real_t (*f)(igraph_real_t x, void *info),
                            void *info, igraph_real_t *Tol, int *Maxit, igraph_real_t *res);
  DECLDIR int igraph_bfgs(igraph_vector_t *b, igraph_real_t *Fmin,
                          igraph_scalar_function_t fminfn, igraph_vector_function_t fmingr,
                          int maxit, int trace,
                          igraph_real_t abstol, igraph_real_t reltol, int nREPORT, void *ex,
                          igraph_integer_t *fncount, igraph_integer_t *grcount);
  DECLDIR int igraph_power_law_fit(const igraph_vector_t* vector, igraph_plfit_result_t* result,
                                   igraph_real_t xmin, igraph_bool_t force_continuous);
  
  __END_DECLS
  
  #endif
  