static inline size_t
bspline_find_interval (const double x, int *flag, gsl_bspline_workspace * w);
static inline int
bspline_process_interval_for_eval (const double x, size_t * i, int flag,
gsl_bspline_workspace * w);
static void
bspline_pppack_bsplvb (const gsl_vector * t,
const size_t jhigh,
const size_t index,
const double x,
const size_t left,
size_t * j,
gsl_vector * deltal,
gsl_vector * deltar, gsl_vector * biatx);
static void
bspline_pppack_bsplvd (const gsl_vector * t,
const size_t k,
const double x,
const size_t left,
gsl_vector * deltal,
gsl_vector * deltar,
gsl_matrix * a,
gsl_matrix * dbiatx, const size_t nderiv);