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## Re: Use of fsolve

**From**: |
Daniel Tourde |

**Subject**: |
Re: Use of fsolve |

**Date**: |
Fri, 02 Oct 1998 10:36:24 +0200 |

Hello Mario,
>* > I would like to use the fsolve solution for solving non-linear equations*
>* > where sometimes, solutions or constant are very small:*
>* *
>* > y(1) = 12*((x(3)*x(1))/2)/E - nlcoef(3);*
>* > y(2) = 12*((x(3)*x(2)+x(1)*x(4))/6)/E - nlcoef(4);*
>* > y(3) = 12*((P*x(3)/2+x(4)*x(2)+x(1)*x(5))/12)/E - nlcoef(5);*
>* > y(4) = 12*((P*x(4)/2+x(5)*x(2))/20)/E - nlcoef(6);*
>* > y(5) = 12*((P*x(5))/60)/E - nlcoef(7);*
>* *
>* > Where some of my nlcoef values are very small (between 1e-7 and 1e-10).*
>* > It happens that the solutions given by fsolve can be wrong due to*
>* > rounding and precision errors.*
>* Perhaps you can get better values by rescaling the problem. *
Thanks for your answer. Yes it has answered my question and helped me to
solve my problem (at least I got answers with index 1).
>* Are E and P also small?*
No, around 1e5 for E and 50 for P
>* Hope this helps,*
It has. Thanks
Daniel
--
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Daniel TOURDE E-mail : address@hidden
The Aeronautical Research Institute of Sweden Tel : +46 8 634 13 44
P.O. Box 11021 S-161 11 BROMMA, Sweden Fax : +46 8 25 34 81
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