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Topic: calculation of exp(200)
Replies: 5   Last Post: Jul 10, 2014 12:51 AM

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kumar vishwajeet

Posts: 88
Registered: 4/6/10
Re: calculation of exp(200)
Posted: Jul 8, 2014 7:15 PM
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"Nasser M. Abbasi" wrote in message <lpfj5e$4c4$1@speranza.aioe.org>...
> On 7/7/2014 8:26 PM, kumar vishwajeet wrote:
> > I want to find exp(N) where N can range from 0 to 200.
> >Is there any method to calculate it with good accuracy?

>
> as James said, you can use vpa
>
> vpa(exp(sym(200)),500)
>
>
> 7225973768125749258177477042189305697356874428527
> 31928403269789123221909361473891661561.9265890625
> 7055746840204310142941817711067711936822648098307
> 7273278800877934252667473057807294372135876617806
> 9702350324220401483115192088442120622525378469924
> 9272881421981093552839024711140014485905504285329
> 2850053281888896583514044902234770562940736477036
> 9022153799888245922895391403712478563813079673045
> 5316370477078232246232166391756343572294659379732
> 9550687822348546666476886365318979823972170480437
> 40943587594
>
> But you have to do all the rest of the computation
> is syms land, otherwise what is the point of
> getting this accuracy if you can't use it in
> numerical matlab.
>
>
>

Actually I have a matrix whose elements range from exp(200) to exp(-200). The matrix is ill conditioned with conditioning number of 10^167. I am calculating determinant of this matrix. MATLAB gives it in the 10^-13. The matrix is posted in the following link.
http://math.stackexchange.com/questions/859597/determinant-of-an-ill-conditioned-matrix/859614#859614
So, I was just wondering whether to rely on this calculation of determinant or not.



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