text: double d_epsilon ( void );
  double d_max ( double x, double y );
  double d_min ( double x, double y );
  void d2vec_part_quick_a ( int n, double a[], int *l, int *r );
  void d2vec_permute ( int n, double a[], int p[] );
  int *d2vec_sort_heap_index_a ( int n, double a[] );
  void d2vec_sort_quick_a ( int n, double a[] );
  int diaedg ( double x0, double y0, double x1, double y1, double x2, double y2,
    double x3, double y3 );
  void dmat_transpose_print ( int m, int n, double a[], const char *title );
  void dmat_transpose_print_some ( int m, int n, double a[], int ilo, int jlo,
    int ihi, int jhi, const char *title );
  void dmat_uniform ( int m, int n, double b, double c, int *seed, double r[] );
  int dtris2 ( int point_num, double point_xy[], int *tri_num,
    int tri_vert[], int tri_nabe[] );
  bool dvec_eq ( int n, double a1[], double a2[] );
  bool dvec_gt ( int n, double a1[], double a2[] );
  bool dvec_lt ( int n, double a1[], double a2[] );
  void dvec_print ( int n, double a[], const char *title );
  void dvec_swap ( int n, double a1[], double a2[] );
  int i_max ( int i1, int i2 );
  int i_min ( int i1, int i2 );
  int i_modp ( int i, int j );
  int i_sign ( int i );
  int i_wrap ( int ival, int ilo, int ihi );
  void imat_transpose_print ( int m, int n, int a[], const char *title );
  void imat_transpose_print_some ( int m, int n, int a[], int ilo, int jlo,
    int ihi, int jhi, const char *title );
  void ivec_heap_d ( int n, int a[] );
  int *ivec_indicator ( int n );
  void ivec_sort_heap_a ( int n, int a[] );
  void ivec_sorted_unique ( int n, int a[], int *nuniq );
  int lrline ( double xu, double yu, double xv1, double yv1, double xv2,
    double yv2, double dv );
  bool perm_check ( int n, int p[] );
  void perm_inv ( int n, int p[] );
  int *points_delaunay_naive_2d ( int n, double p[], int *ntri );
  int s_len_trim ( const char *s );
  int swapec ( int i, int *top, int *btri, int *bedg, int point_num,
    double point_xy[], int tri_num, int tri_vert[], int tri_nabe[],
    int stack[] );
  void timestamp ( void );
  char *timestring ( void );
  double *triangle_circumcenter_2d ( double t[] );
  bool triangulation_plot_eps ( const char *file_out_name,
    int g_num, double g_xy[], int tri_num, int nod_tri[] );
  void triangulation_print ( int point_num, double xc[], int tri_num,
    int tri_vert[], int tri_nabe[] );
  void vbedg ( double x, double y, int point_num, double point_xy[], int tri_num,
    int tri_vert[], int tri_nabe[], int *ltri, int *ledg, int *rtri, int *redg );
  