Re: Reconstructing data points from a InterpolatingFunction object
- To: mathgroup at smc.vnet.net
- Subject: [mg66515] Re: Reconstructing data points from a InterpolatingFunction object
- From: Paul Abbott <paul at physics.uwa.edu.au>
- Date: Wed, 17 May 2006 03:30:38 -0400 (EDT)
- Organization: The University of Western Australia
- References: <e4bits$1a9$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
In article <e4bits$1a9$1 at smc.vnet.net>,
"Eckhard Schlemm" <e.schlemm at hotmail.de> wrote:
> I am nummerically solving a differential equation using NDSolve and then I
> want to apply a NonlinearFit on the resulting InterpolatingFunction
> object....
What do you want the NonlinearFit to do? Note that in Version 5 you can
use FindFit instead of NonlinearFit. Also, you can use
InterpolatingFunctions directly, rather than sampling or re-sampling
them.
I think a concrete example is likely to generate a more useful answer.
> and therefore need to have access to the data points which NDSolve
> created and from which the InterpolatingFunction is created....
I don't follow the use of therefore here. The data points at which
NDSolve samples the solution depends on the automatic and optional
settings supplied to NDSolve -- so I don't see why accessing these
points is required. You can, of course, just generate a Table of points
by re-sampling the InterpolatingFunction.
> Is there any fast and direct way to get these data points ?
> (There must be....)
See the Advanced Documentation for NDSolve. This can be opened directly
be executing the following command:
NotebookOpen[FrontEnd`FileName[
{$TopDirectory, "Documentation", "English","RefGuide",
"AdvancedDocumentation","DifferentialEquations"}, "Packages.nb"]]
Cheers,
Paul
_______________________________________________________________________
Paul Abbott Phone: 61 8 6488 2734
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