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joon
08/04/12 01:23am

Hi,

I am trying to fit a 1-dimensional data with eigenvectors. Here is my test code to see if this is possible.

f[a0_, b0_] := Module[{M, eigv},
M = {{a0, 0, 3}, {0, b0, 0}, {3, 0, 7}};
eigv = Eigenvectors[N[M]];
Return[Flatten[eigv]]
]

This function returns a 1-dimensional list. I generate a dataset by using this function for convenience:
data = f[2, 5]
Then I get the data:
{0.424155, 0., 0.905589, 0., -1., 0., -0.905589, 0., 0.424155}

Now I try to fit the data using following expression:
testfit = FindFit[data, f[a, b][[x]], {{a, 3.1}, {b, 5.3}}, x]

I get following warnings and a result:
Part::pspec: Part specification x is neither an integer nor a list of integers. >>
Part::pspec: Part specification #10 is neither an integer nor a list of integers. >>
{a -> 7.57549, b -> 5.3}

The goal was to fit the one dimensional vector with an one dimensional vector generated by f[a,b][[x]]. In this process we compare each element of those two 1-dim lists.

Apparently the result is far from being correct, and I get warnings. Is this idea possible to implement in Mathematica at all?

Thanks!



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Subject (listing for 'fit data with eigenvectors')
Author Date Posted
fit data with eigenvectors joon 08/04/12 01:23am
Re: fit data with eigenvectors Bill Simpson 08/05/12 00:07am
Re: fit data with eigenvectors Peter Pein 08/05/12 02:38am
Re: fit data with eigenvectors Peter Pein 08/05/12 02:52am
Re: fit data with eigenvectors joon 08/21/12 5:02pm
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