Hi! I am currently using 2D interpolation with Bicubic spline and I have found out that there was no higher level interface for extrapolation function. Thus, I have added the following function in my work code:
static double > gsl_spline2d_eval_extrap (const gsl_spline2d * interp, const double x, > const double y, gsl_interp_accel * > xa, > gsl_interp_accel * ya) > { > return gsl_interp2d_eval_extrap (&(interp->interp_object), interp->xarr, > interp->yarr, interp->zarr, x, y, xa, > ya); > } > I hope this could be added in the future release of GSL. Kind regards, Brijesh