non-linear curve fitting with 3 independent variables - suggest a software in Linux



Hello,

I want to fit a curve of the type

f(x,y,z) = a + b*x + c*y + (d/z + e*x/z + f*y/z);

to the dataset listed at the end of the post.

Is there any curve fitting program available in Linux to automate this?

I tried to use GNUPLOT but I think it does not handle more than 2
independent variables.

It would be nice if there is a script like language in that softaware
to fit the curve since I have more than 100 datasets like this.

/// DATASET
x y z f(x,y,z)
1 1.88 0.3666 1.090e-10
1 1.96 0.3978 1.165e-10
1 2.08 0.351 1.147e-10
1 2.16 0.3822 1.244e-10
11 1.8 0.4134 4.724e-11
11 1.92 0.3666 4.675e-11
11 2 0.3978 4.913e-11
11 2.12 0.351 5.116e-11
11 2.2 0.3822 5.569e-11
21 1.84 0.4134 4.591e-11
21 1.96 0.3666 4.531e-11
21 2.04 0.3978 4.798e-11
21 2.16 0.351 5.039e-11
31 1.8 0.3822 4.257e-11
31 1.88 0.4134 4.582e-11
31 2 0.3666 4.512e-11
31 2.08 0.3978 4.887e-11
31 2.2 0.351 5.101e-11
41 1.84 0.3822 4.308e-11
41 1.92 0.4134 4.604e-11
41 2.04 0.3666 4.535e-11
41 2.12 0.3978 5.034e-11
51 1.8 0.351 4.051e-11
51 1.88 0.3822 4.365e-11
51 1.96 0.4134 4.635e-11
51 2.08 0.3666 4.610e-11
51 2.16 0.3978 5.175e-11
61 1.84 0.351 4.110e-11
61 1.92 0.3822 4.417e-11
61 2 0.4134 4.671e-11
61 2.12 0.3666 4.785e-11
61 2.2 0.3978 5.295e-11
71 1.88 0.351 4.185e-11
71 1.96 0.3822 4.463e-11
71 2.04 0.4134 4.726e-11
71 2.16 0.3666 4.954e-11
81 1.8 0.3978 4.233e-11
81 1.92 0.351 4.252e-11
81 2 0.3822 4.505e-11
81 2.08 0.4134 4.867e-11
81 2.2 0.3666 5.093e-11
91 1.84 0.3978 4.318e-11
91 1.96 0.351 4.305e-11
91 2.04 0.3822 4.555e-11
91 2.12 0.4134 5.057e-11
101 1.8 0.3666 4.077e-11
101 1.88 0.3978 4.394e-11
101 2 0.351 4.350e-11
101 2.08 0.3822 4.648e-11
101 2.16 0.4134 5.218e-11

Thanks for your help
Anand

.



Relevant Pages

  • Only 7.8 Billion (was: 9 Billion. The Population Explosion Is At And End.)
    ... This does, in fact, fit very well. ... deviations of about 10-20 million and is not a direct fit. ... The results of fitting this to the above-mentioned regularity ... surprising recent development in the world population curve. ...
    (sci.anthropology)
  • Re: comparison of two distribution curves
    ... john wrote: ... > is it as simple as saying that a straight line has a good fit to the ... Do a one-way anova on the control condition. ... Fit a curve to each condition. ...
    (sci.stat.edu)
  • Re: nlinfit vs. lsqcurvefit
    ... I have a question regading the use of either nlinfit vs. lsqcurvefit. ... I have a number of data that I want to fit with a curve (I know the ... regardless of which optimizer you use. ...
    (comp.soft-sys.matlab)
  • Re: How to get the equation of a curve fitting experimental data?
    ... > I would like to fit a curve to this set of data and get the equation ... > of this curve in order to reach the primitive function Y of y. ... abstracted as a mathematical metaphor to model ... curvefitting toolbox. ...
    (comp.soft-sys.matlab)
  • Re: How to get the equation of a curve fitting experimental data?
    ... >> I would like to fit a curve to this set of data and get the equation ... >> of this curve in order to reach the primitive function Y of y. ... I did some model-based studies of seismic waves. ... > The best material model of a cat is another, or preferably the same, cat. ...
    (comp.soft-sys.matlab)

Loading