# Re: FW: lspoly didn't wok when the number of data points equal to the number of coefficients

From: Dennis Shea <shea_at_nyahnyahspammersnyahnyah>
Date: Sat Dec 28 2013 - 08:26:49 MST

As noted in the documentation:

n

The number of coefficients desired (i.e., n-1 will be the degree of the
polynomial). Due to the method used, n should be less than or equal to
five.

===

In your case with 3 points, the max number of coefficients would be 2

On 12/28/13, 5:01 AM, Richard Liang wrote:
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> From: richardljy@hotmail.co.uk
> To: ncl-talk@ucar.edu
> Subject: lspoly didn't wok when the number of data points equal to the number of coefficients
> Date: Sat, 21 Dec 2013 15:45:08 -0500
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> lspoly didn't wok when the number of data points equal to the number of coefficientsI did the test
> x = (/-4.5, -3.2, -1.4/)y = (/ 0.7, 2.3, 3.8/)n = 3 c = lspoly(x,y, 1, n) print(c)c will be(0) 1e+20(1) 1e+20(2) 1e+20
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> But if n=2 c will be(0) 5.268707(1) 0.9896836
> I also did the test in the 4 element array, when n=4, it didn't work. only when n is less than the number of data points
> Any body help me? thanks
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Received on Sat Dec 28 08:29:28 2013

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