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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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