[Bug-gsl] extension to gsl_interpolation

[Feng Chen]

Hi all,

I have an extension for GSL interpolation package, to allow:

1)      Different boundary conditions for cspline, e.g., parabolic runout
condition.

2)      Linear search than binary search (for processing group of ordered
x-values, reducing cost)
3)      Extrapolation (default is still dis-allowing extrapolation).  In a
lot of time I need to extrapolate the value by less than one grid … In
other cases I need to show the extrapolated values for demonstration
purpose.


I really would like it to be an extension only, but w/o touching the core,
it’s difficult.  Thus I did a minimal change on the core and hope it can be
incorporated into the next GSL release. These changes are all in the diff
directory as diff files (based on version 1.15).


I also included gsl_interp_ext.c and gsl_interp_ext.h as a demonstration.
The bottom half of gsl_interp_ext.c might be suitable to add to the CORE
lib, or leave as an extension alone.

Best!

--
Feng Chen

gsl_ext.tar.gz
Description: GNU Zip compressed data