About TCurveFittingFunction?

TeeChart VCL for Borland/CodeGear/Embarcadero RAD Studio, Delphi and C++ Builder.
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Gas0189
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About TCurveFittingFunction?

Post by Gas0189 » Mon Aug 07, 2006 3:25 am

When I get the polynomial coefficients using TCurveFittingFunction, I can't understand.

For example, I have a datasource: (y = 5 + 3*x + 2 * x^2)
1,10
3,32
6,95
8,157
10,235

Using the TCurveFittingFunction, I get the fitting polynomial:
y = 0*x + 7*x^2 + 2*x^3
It's not the same as (y = 5 + 3*x + 2 * x^2).

Why?

Berntsen
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Post by Berntsen » Mon Aug 07, 2006 9:12 am

Hi

The curvefitting fits normalised data. That is Y-MinY and X-MinX (In your case Y-10 and X-1). Re-inserting this into the fitted polynomial should yield the original equation.

Regards Jørgen

Gas0189
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To Berntsen:

Post by Gas0189 » Mon Sep 11, 2006 3:49 am

Thanks.

I got it.

CCRyder
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Post by CCRyder » Tue Sep 19, 2006 6:40 pm

Hi Gas0189,
Could you possibly show me how to do this? (Not a Math Genie)

Thanks!!
Regards,
CCRyder

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