Re: saddlepoint approx, solving a sum
- To: mathgroup at smc.vnet.net
- Subject: [mg119670] Re: saddlepoint approx, solving a sum
- From: DrMajorBob <btreat1 at austin.rr.com>
- Date: Fri, 17 Jun 2011 00:07:25 -0400 (EDT)
- References: <201106160800.EAA13170@smc.vnet.net>
- Reply-to: drmajorbob at yahoo.com
Show us your Solve statement. Otherwise, we're guessing.
Bobby
On Thu, 16 Jun 2011 03:00:10 -0500, gideonmath
<g.s.j.cramwinckel at students.uu.nl> wrote:
> For a saddlepoint approximation i need to solve the following equation:
> K'[t]==y^*,t
>
> K[t_]:= Sum[Log[1-p[i]+p[i]Exp[c[i]t]], {i,1,n}]
> where p[i] denotes a probability (hence all p[i] in (0,1) and \sum
> p_i=1. Same holds for the c[i], but c[i], p[i] all independent.
>
> Solve works for a 1-term Sum, but for 2 or more terms I get this error:
> Solve::nsmet: This system cannot be solved with the methods available to
> Solve. >>
>
> Why does the method fail? I suppose that it has to do something with the
> log[..+...] kind of terms.
> IS there a workaround?
>
--
DrMajorBob at yahoo.com
- References:
- [Mathematica8,solve] saddlepoint approx, solving a sum
- From: gideonmath <g.s.j.cramwinckel@students.uu.nl>
- [Mathematica8,solve] saddlepoint approx, solving a sum