void jn_zeros ( int n, int nt, double z[] );
void yn_zeros ( int n, int nt, double z[] );
void jyndd ( int n, double x, double *bjn, double *djn, double *fjn, 
  double *byn, double *dyn, double *fyn );
void jyzo ( int n, int nt, double rj0[], double rj1[], double ry0[], 
  double ry1[] );