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>