Hello all, Just in case it hasn't been said explicitly, a GSL interpolation type which preserves monotonicity and keeps the same interface as the other GSL interpolation types would certainly be welcome!
Take care, Andrew http://o2scl.sourceforge.net On Fri, Mar 2, 2012 at 10:57 AM, Feng Chen <fchen0...@gmail.com> wrote: > How about this one? (The green curve does not look like monotonic to me > though ... The blue curve is the reference you cited) > > MESA/INTERP_1D > monotonicity preserving cubic interpolation > piecewise monotonic cubic interpolation > > http://mesa.sourceforge.net/interp_1D.html > > > On Thu, Mar 1, 2012 at 1:30 PM, Christian Krueger <mangrove...@gmail.com> > wrote: >> >> Hi... is there any possibility to get a strictly monotone interpolation > function? >> >> I have data which for sure have to be monotone, but the provided > interpolation methods (cspline, akima) do not preserve this condition > (linear interpolation is not smooth and polynomial of course useless with > 200+ datapoints). >> >> I wonder whether the method of Steffen (1990) is implemented somewhere > which seem to have some nice features (monotonicity, almost no spurious > oscillations)? Or might it be a useful extension for GSL? >> Found in this paper: A simple method for monotonic interpolation in one > dimension, Astron. Astrophys. 239, 443 (1990) >> >> >> Regards, >> Christian >>