Re: interpolating f(x,y) from evaluation
- To: mathgroup at smc.vnet.net
- Subject: [mg8651] Re: interpolating f(x,y) from evaluation
- From: Paul Abbott <paul at physics.uwa.edu.au>
- Date: Fri, 12 Sep 1997 04:11:04 -0400
- Organization: University of Western Australia
- Sender: owner-wri-mathgroup at wolfram.com
K. Nikolaj Berntsen wrote:
> I want to generate an interpolatingfunction-like object for a
> complicated function of several variables; Interpolation etc. does not
> seem to be able to; but I may have missed something in the
> documentation, anyone got an idea?
>
> I tried:
>
> Interpolation[Table[{f[i,j].i.j},{i,3},{j,3}]]
The argument to interpolation needs to be "flattened" and should be of
the form
Flatten[Table[{i,j,f[i,j]},{i,3},{j,3}],1]
(Note that you had {f[i,j].i.j} instead of {i,j,f[i,j]}). For example,
In[1]:= f[i_, j_] := i^2 + j^2
In[2]:= Interpolation[Flatten[Table[{i,j,f[i,j]},{i,5},{j,5}],1]];
In[3]:= Plot3D[%[x, y], {x, 1, 5}, {y, 1, 5}];
Alternatively you can use FunctionInterpolation:
In[4]:= FunctionInterpolation[f[i, j], {i, 1, 5}, {j, 1, 5}];
In[4]:= FunctionInterpolation[f[i, j], {i, 1, 5}, {j, 1, 5}];
In[5]:= Plot3D[%[x, y], {x, 1, 5}, {y, 1, 5}];
Cheers,
Paul
____________________________________________________________________
Paul Abbott Phone: +61-8-9380-2734
Department of Physics Fax: +61-8-9380-1014
The University of Western Australia
Nedlands WA 6907 mailto:paul at physics.uwa.edu.au
AUSTRALIA http://www.pd.uwa.edu.au/Paul
God IS a weakly left-handed dice player
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