Re: fitting a function

• To: mathgroup at smc.vnet.net
• Subject: [mg58362] Re: [mg58323] fitting a function
• From: "David Park" <djmp at earthlink.net>
• Date: Tue, 28 Jun 2005 21:56:56 -0400 (EDT)
• Sender: owner-wri-mathgroup at wolfram.com

```Darrell,

First, get rid of the commas in your data.

data = {{10000, .3}, {15000, .5}, {20000, .6}, {25000, .65}};

<< NumericalMath`PolynomialFit`

poly = PolynomialFit[data, 3]
FittingPolynomial[<>, 3]

Plot[poly[x], {x, 10000, 25000},
Epilog -> {AbsolutePointSize[5], Point /@ data},
Frame -> True,
ImageSize -> 450];

David Park

From: Bosch, Darrell [mailto:bosch at vt.edu]
To: mathgroup at smc.vnet.net

Dear Group,  I have two questions:  First, I want to fit a function
relating utility to income based on some elicited data.  For example,
the following pairs might represent the income and utility values for an
individual:  {10,000, .3}, {15,000, .5}, {20,000, .6}, {25,000, .65}  I
want to fit the data to a function and plot the resulting function.
What is the best way to do this?  PolynomialFit seems like a logical
choice, but it's not clear to me from the documentation how to specify
the command for a series of pairs of points.

Second, how do I plot the resulting value of a polynomial fit in the
example below?  My 'ParametricPlot' command doesn't do the job.  Thanks

<< "NumericalMath`PolynomialFit`"

In[28]:=

p = PolynomialFit[{1, 4, 9,

16, 25, 36, 49}, 3]

ParametricPlot[p, {p, 0, 6}, PlotRange -> All, Compiled -> True]

```

• Prev by Date: Re: Common factors in a list
• Next by Date: New Visualization - Earthquake data
• Previous by thread: Re: fitting a function
• Next by thread: Re: fitting a function