Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.soft-sys.math.mathematica > #3133 > unrolled thread

Re: saddlepoint approx, solving a sum

Back to article view | Back to comp.soft-sys.math.mathematica

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.

Contents

  Re: saddlepoint approx, solving a sum DrMajorBob <btreat1@austin.rr.com> - 2011-06-17 04:07 +0000

#3133 — Re: saddlepoint approx, solving a sum

Show us your Solve statement. Otherwise, we're guessing.

Bobby

On Thu, 16 Jun 2011 03:00:10 -0500, gideonmath  
<g.s.j.cramwinckel@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@yahoo.com

[toc] | [standalone]

Back to top | Article view | comp.soft-sys.math.mathematica

csiph-web