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Newsgroups: comp.graphics.apps.gnuplot
Date: Thu, 20 Dec 2012 13:01:38 -0800 (PST)
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Subject: fit gives different results for identical functions with different var names
From: marcus.hanson@gmail.com
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Xref: csiph.com comp.graphics.apps.gnuplot:1548

I am using gnuplot for windows, trying to fit gaussian data. I am doing thi=
s from a program that has to run many fits on different sets of data, so I =
would like to use different variable names. Unfortunately, it seems that un=
less I use single-character names, I get completely unreasonable results. T=
he results are identical for the same data for every function with variable=
 names more than one charcter long, but always reasonable for functions wit=
h variables only one variable long.

For example:=20
fa(xa) =3D aa*exp(-(xa-ma)**2/(2*sa**2))=20
gives results identical to f2(x2) =3D a2*exp(-(x2-m2)**2/(2*s2**2)), but di=
fferent from f(x) =3D a*exp(-(x-m)**2/(2*s**2))

I cannot find any restriction on length of variable names in the documentat=
ion.
Any ideas?