# -*- org -*-
#+CATEGORY: bspline

1. Add functions:

gsl_bspline_smooth to fit smoothing splines to data more efficiently
than the standard least squares inversion (see pppack l2appr and
smooth.spline() from GNU R)

+ any other useful functions from pppack

2. Constrained fits - matching first derivatives?

3. Tests: more tests for gsl_bspline_proj_rhs

4. spline integration - currently implemented with GL quadrature

A more efficient algorithm may be given in:

Gaffney 1976, The calculation of indefinite integrals of B-splines

and also the Dierckx book. An implementation is given in fpintb.f and splint.f of DIERCKX package

5. Greville gsl_bspline_init_greville - is linked to a savannah bug

https://savannah.gnu.org/bugs/index.php?34361
