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## Re: polynome code?

 From: Robert A. Macy Subject: Re: polynome code? Date: Thu, 19 Jan 2006 10:13:42 -0800

```At the risk of looking really, really stupid here...

given x0, x1, y0, y1, doty0, and doty1

what about making the four by four matrix, M =

x0^3, x0^2, x0, 1;
x1^3, x1^2, x1, 1;
3*x0^2, 2*x0, 1, 0;
3*x1^2, 2*x1, 1, 0;

taking the inverse of that matrix:

Minv=inv(M);

then coefficients of polynome, Coeff
= Minv*[(y0, y1, doty0, doty1)];
Coeff=Coeff';
...or so

and you're done.

- Robert -

On Thu, 19 Jan 2006 12:36:16 -0500 (EST)
>    does anybody know of existing code which returns the
> coefficients of
>    one cubic polynome, which are completely defined by 4
> conditions:
>
>    the value of the polynome at two points and the slope
> of the polynome
>    at these two points (one of the slopes is actually
> zero for my
>    application).
>

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