Re: NonlinearFit
- To: mathgroup at smc.vnet.net
- Subject: [mg42168] Re: [mg42109] NonlinearFit
- From: "German Buitrago A." <gerbual at col2.telecom.com.co>
- Date: Sat, 21 Jun 2003 02:49:43 -0400 (EDT)
- References: <200306190759.DAA17984@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Rees:
The problem is in your syntax. Change Exp(-3*x1/a) by Exp[-3*x1/a]. This
way, everything will work well.. Don´t forget to load the package
Statistics`NonlinearFit` previously.
In[1]:=
data = {{0.1, 0.113387476}, {0.2, 0.194633152}, {0.3, 0.252848224},
{0.4, 0.294561145}, {0.5, 0.324449759}, {0.6, 0.345865887},
{0.7, 0.361211213}, {0.8, 0.37220662}, {0.9, 0.380085173},
{1., 0.385730403}};
In[2]:=
<< "Statistics`NonlinearFit`"
In[6]:=
NonlinearFit[data, c*(1 - Exp[-3*x1/a]), {x1}, {c, a}]
Out[6]=
0.4*(1 - E^(-3.33333*x1))
German Buitrago A.
Manizales, Colombia
----- Original Message -----
From: "Rees" <civnrn at hotmail.com>
To: mathgroup at smc.vnet.net
Subject: [mg42168] [mg42109] NonlinearFit
> Hi,
>
> Please could someone assist me in curve fitting.
>
> I have the following x,y data
>
> data = {{0.1,0.113387476}, {0.2, 0.194633152}, {0.3,
> 0.252848224}, {0.4, 0.294561145}, {0.5,
> 0.324449759}, {0.6, 0.345865887}, {0.7,
> 0.361211213}, {0.8, 0.37220662}, {0.9,
> 0.380085173}, {1.0, 0.385730403}};
>
> Now I wish to fit an exponential curve of the form below to it:
>
> c*[1-Exp(-3x/a]
>
> where c and a are parameters to be determined.
>
> I tried the following but it doesn't work:
>
> NonlinearFit[data, c*(1 - Exp(-3*x1/a)), {x1}, {c, a}]
>
>
> Please advise.
>
> Thanks is advance
>
> Rees
>
- References:
- NonlinearFit
- From: civnrn@hotmail.com (Rees)
- NonlinearFit