text: /* Copyright (c) 2007-2014 Massachusetts Institute of Technology
   *
   * Permission is hereby granted, free of charge, to any person obtaining
   * a copy of this software and associated documentation files (the
   * "Software"), to deal in the Software without restriction, including
   * without limitation the rights to use, copy, modify, merge, publish,
   * distribute, sublicense, and/or sell copies of the Software, and to
   * permit persons to whom the Software is furnished to do so, subject to
   * the following conditions:
   * 
   * The above copyright notice and this permission notice shall be
   * included in all copies or substantial portions of the Software.
   * 
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
   * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
   * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
   * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 
   */
  
  #ifndef NLOPT_UTIL_H
  #define NLOPT_UTIL_H
  
  #include <stdlib.h>
  #include <stdarg.h>
  #include <math.h>
  #include "nlopt_config.h"
  
  #include "nlopt.h"
  
  /* workaround for Solaris + gcc 3.4.x bug (see configure.ac) */
  #if defined(__GNUC__) && defined(REPLACEMENT_HUGE_VAL)
  #  undef HUGE_VAL
  #  define HUGE_VAL REPLACEMENT_HUGE_VAL
  #endif
  
  #ifndef HAVE_COPYSIGN
     /* not quite right for y == -0, but good enough for us */
  #  define copysign(x, y) ((y) < 0 ? -fabs(x) : fabs(x))
  #endif
  
  #ifdef __cplusplus
  extern "C" {
  #endif                          /* __cplusplus */
  
      int nlopt_isinf(double x);
      int nlopt_isfinite(double x);
      int nlopt_istiny(double x);
      int nlopt_isnan(double x);
  
  /* re-entrant qsort */
      extern void nlopt_qsort_r(void *base_, size_t nmemb, size_t size, void *thunk, int (*compar) (void *, const void *, const void *));
  
  /* seconds timer */
      extern double nlopt_seconds(void);
      extern unsigned long nlopt_time_seed(void);
  
  /* pseudorandom number generation by Mersenne twister algorithm */
      extern void nlopt_init_genrand(unsigned long s);
      extern double nlopt_urand(double a, double b);
      extern int nlopt_iurand(int n);
      extern double nlopt_nrand(double mean, double stddev);
  
  /* Sobol' low-discrepancy-sequence generation */
      typedef struct nlopt_soboldata_s *nlopt_sobol;
      extern nlopt_sobol nlopt_sobol_create(unsigned sdim);
      extern void nlopt_sobol_destroy(nlopt_sobol s);
      extern void nlopt_sobol_next01(nlopt_sobol s, double *x);
      extern void nlopt_sobol_next(nlopt_sobol s, double *x, const double *lb, const double *ub);
      extern void nlopt_sobol_skip(nlopt_sobol s, unsigned n, double *x);
  
  /* stopping criteria */
      typedef struct {
          unsigned n;
          double minf_max;
          double ftol_rel;
          double ftol_abs;
          double xtol_rel;
          const double *xtol_abs;
          int *nevals_p, maxeval;
          double maxtime, start;
          int *force_stop;
          char **stop_msg;        /* pointer to msg string to update */
      } nlopt_stopping;
      extern int nlopt_stop_f(const nlopt_stopping * stop, double f, double oldf);
      extern int nlopt_stop_ftol(const nlopt_stopping * stop, double f, double oldf);
      extern int nlopt_stop_x(const nlopt_stopping * stop, const double *x, const double *oldx);
      extern int nlopt_stop_dx(const nlopt_stopping * stop, const double *x, const double *dx);
      extern int nlopt_stop_xs(const nlopt_stopping * stop, const double *xs, const double *oldxs, const double *scale_min, const double *scale_max);
      extern int nlopt_stop_evals(const nlopt_stopping * stop);
      extern int nlopt_stop_time_(double start, double maxtime);
      extern int nlopt_stop_time(const nlopt_stopping * stop);
      extern int nlopt_stop_evalstime(const nlopt_stopping * stop);
      extern int nlopt_stop_forced(const nlopt_stopping * stop);
  
  /* like vsprintf, but reallocs p to whatever size is needed */
      extern char *nlopt_vsprintf(char *p, const char *format, va_list ap);
      extern void nlopt_stop_msg(const nlopt_stopping * s, const char *format, ...)
  #ifdef __GNUC__
          __attribute__ ((format(printf, 2, 3)))
  #endif
          ;
  
  /* for local optimizations, temporarily setting eval/time limits */
      extern nlopt_result nlopt_optimize_limited(nlopt_opt opt, double *x, double *minf, int maxevals, double maxtime);
  
  /* data structure for nonlinear inequality or equality constraint
     (f <= 0 or f = 0, respectively).  tol (>= 0) is a tolerance
     that is used for stopping criteria -- the point is considered
     "feasible" for purposes of stopping if the constraint is violated
     by at most tol. */
      typedef struct {
          unsigned m;             /* dimensional of constraint: mf maps R^n -> R^m */
          nlopt_func f;           /* one-dimensional constraint, requires m == 1 */
          nlopt_mfunc mf;
          nlopt_precond pre;      /* preconditioner for f (NULL if none or if mf) */
          void *f_data;
          double *tol;
      } nlopt_constraint;
  
      extern unsigned nlopt_count_constraints(unsigned p, const nlopt_constraint * c);
      extern unsigned nlopt_max_constraint_dim(unsigned p, const nlopt_constraint * c);
      extern void nlopt_eval_constraint(double *result, double *grad, const nlopt_constraint * c, unsigned n, const double *x);
  
  /* rescale.c: */
      double *nlopt_compute_rescaling(unsigned n, const double *dx);
      double *nlopt_new_rescaled(unsigned n, const double *s, const double *x);
      void nlopt_rescale(unsigned n, const double *s, const double *x, double *xs);
      void nlopt_unscale(unsigned n, const double *s, const double *x, double *xs);
      void nlopt_reorder_bounds(unsigned n, double *lb, double *ub);
  
  #ifdef __cplusplus
  }                               /* extern "C" */
  #endif                          /* __cplusplus */
  #endif
  