Re: Exponential fit question.
- To: mathgroup at smc.vnet.net
- Subject: [mg28039] Re: [mg27986] Exponential fit question.
- From: "Sherman Reed" <sherman.reed at worldnet.att.net>
- Date: Thu, 29 Mar 2001 03:24:07 -0500 (EST)
- References: <200103270626.BAA21789@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Joe,
certainly the use of Fit with Exp does not work.
I resort to fundamentals in this problem. I took the natural log of the
y values, and then fitted a first order linear equation.
working this backward, I got 5.22289*Exp[.03795*x]
I plotted this versus your data and the fit was reasonable.
I plotted your Excel result versus your data and this was
substantially poorer. I suspect an error in the Excel work.
the code is attached.
Sherman C. Reed
sherman.reed at att.net
----- Original Message -----
From: "joe" <joe at wam.umd.edu>
To: mathgroup at smc.vnet.net
Subject: [mg28039] [mg27986] Exponential fit question.
> hello.
>
> I was wondering if someone could help me with the following problem.
>
> I am trying to perform an exponential fit to the following data
> {{x,y}}
>
> data
> ={{50,22},{64,62},{78,122},{93,269},{107,414},{122,507},{136,597}}
>
> Fit[data,Exp[x],x]
>
> what I get is
>
> 1.94272422061017735^-63 *E^x Which is not correct.
>
> With Excel I get 7.5*E^0.0034x which is correct.
>
> How can I do this with Mathematica ?
>
> Thanks.
> -Joseph.
>
>
>
------=_NextPart_000_0017_01C0B72D.8D281700
filename="zzstan.nb"
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------=_NextPart_000_0017_01C0B72D.8D281700--
- References:
- Exponential fit question.
- From: joe <joe@wam.umd.edu>
- Exponential fit question.