[SciPy-user] derivative

Nils Wagner nwagner at mecha.uni-stuttgart.de
Wed Feb 23 08:10:31 CST 2005


Stephen Walton wrote:

> Nils Wagner wrote:
>
>> Hi all,
>>
>> Is it somehow possible to improve the accuracy of derivative ?
>
>
> Higher order?
>
> from scipy import *
>
> def func(x):
>  return exp(2*x)
>
> for i in arange(1,6):
> d=derivative(func,0.0,dx,i,order=9)
> print i,' derivative of exp(2*x) at x=0',d,'exact',2**i
> print '   rel error %e' % (d/2**i - 1)
>
> Changing the order to 9 improves the accuracy of the 6th derivative 
> from 1e-4 to 3e-7.
>
The problem is that I need very accurate results, since I want to use 
them as an input of
cof in SUBROUTINE pade (see my previous E-mail Pade Approximants).
cof contains the leading terms of the power series expansion of a function.

Nils

> _______________________________________________
> SciPy-user mailing list
> SciPy-user at scipy.net
> http://www.scipy.net/mailman/listinfo/scipy-user



 




More information about the SciPy-user mailing list