[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Help-gsl] monotone interpolation

From: Christian Krueger
Subject: Re: [Help-gsl] monotone interpolation
Date: Fri, 02 Mar 2012 13:54:30 +0000
User-agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv: Gecko/20120216 Thunderbird/3.1.19

Interesting. Other possibilities are of course welcome.

The other one in that graph *might* be close to the one on wiki?
I will read that paper soon.

However, I would prefer to have a GSL implementation.

I implemented the wikipedia suggestion already quick&dirty, but I am not entirely happy with that. It is sometimes more wiggly than a usual CSpline.

On 03/02/2012 01:57 AM, Feng Chen wrote:
How about this one? (The green curve does not look like monotonic to me
though ... The blue curve is the reference you cited)
monotonicity preserving cubic interpolation
piecewise monotonic cubic interpolation
On Thu, Mar 1, 2012 at 1:30 PM, Christian Krueger <address@hidden
<mailto:address@hidden>> 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

reply via email to

[Prev in Thread] Current Thread [Next in Thread]