[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
## Re: polyfit problem?

**From**: |
ldoolitt |

**Subject**: |
Re: polyfit problem? |

**Date**: |
Tue, 16 Mar 1999 17:25:30 -0500 (EST) |

Hi -
>* When I use octave to get a 9th degree polynomial for xy below, via*
>* polyfit I get very strange coefficients, while when I use gnuplot's fit*
>* capability on the same data I get reasonable coefficients.*
octave's polyfit does no pre-scaling before setting up the matrix.
I find that necessary for any kind of real work with polynomial fits.
When I ran into this, I prescaled the data before calling polyfit,
rather than "fixing" polyfit. Sorry.
- Larry