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From:  P <prashanthramu@gmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: syms and vpa problem
Date: Tue, 07 Aug 2007 20:02:18 -0000
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On Aug 7, 4:00 pm, P <prashanthr...@gmail.com> wrote:
> Hi all,
>
> I have a variable called
>
> sym_dPhi =
> -282270057375923/2361183241434822606848*cos(phis
> +2835403426559781/1125899906842624)-5849622991223293/18889465931478580854784*cos(phis
> +1649123417284613/281474976710656)+8867307977828847/75557863725914323419136*cos(phis
> +1667188769632673/281474976710656)-6776253911855553/18889465931478580854784*cos(phis
> +5867111522062989/9007199254740992)+7154406299740559/75557863725914323419136*cos(phis
> +6355945788037667/1125899906842624)
>
> where phis is created as syms phis.
>
> vpa(sym_dyPhi,5) yields me
> ans =
>
> [ empty sym ]
>
> Why ?
>
> On a parallel line ...
>
> >> syms B
> >> syms c; B = 1 + pi + c
>
> B =
> 1165754695714211/281474976710656+c
>
> >> vpa(B,2)
>
> ans =
>  4.1+c
>
> Works !
>
> How come ? What am I doing wrong ? Any suggestions ?
>
> Thanks,
> ethnicatom

please note even vpa(sym_dyPhi,25) yields me no answer !