RE: data fitting function
- To: mathgroup at smc.vnet.net
- Subject: [mg40833] RE: [mg40823] data fitting function
- From: "David Park" <djmp at earthlink.net>
- Date: Mon, 21 Apr 2003 06:58:09 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
gong,
Use
f[x_] = Fit[X,{functions},x]
Use = and not := in this case. That defines f[x] once and for all. Then you
should be able to use it rather efficiently in other expressions.
Function has the attributes HoldAll so when your f is used, the Fit is
reevaluated with each use. That's not efficient.
David Park
djmp at earthlink.net
http://home.earthlink.net/~djmp/
From: gong [mailto:gongli at cutey.com]
To: mathgroup at smc.vnet.net
hi
i would like to fit some data X = {{x1,y1},...,{xn,yn}} to a set of
functions, then have this assigned to a function i can call:
fittedfunc[x1] \approx y1
moreover, i need fittedfunc to be as fast as possible in terms of
evaluation, since it will be used in a loop. i think it should be
ideally a compiled function.
i tried
f=Function[x,Fit[X,{functions},x]
bit im finding a major speed hit here, i think every time i call f[x]
it refits the data.
any help would be greatly appreciated.
-gong