MathGroup Archive 2007

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: how to plot a 2-parametric output from Solve with

  • To: mathgroup at smc.vnet.net
  • Subject: [mg72536] Re: [mg72518] how to plot a 2-parametric output from Solve with
  • From: Bob Hanlon <hanlonr at cox.net>
  • Date: Fri, 5 Jan 2007 02:18:13 -0500 (EST)
  • Reply-to: hanlonr at cox.net

sol=Solve[{x==1+a*y,y==9+b*x},{x,y}]

{{x -> -((1 + 9*a)/(-1 + a*b)), 
   y -> -((9 + b)/(-1 + a*b))}}

sol11[a_,b_]=sol[[1,1,2]]

-((1 + 9*a)/(-1 + a*b))

sol12[a_,b_]=sol[[1,2,2]]

-((9 + b)/(-1 + a*b))

Plot3D[sol11[a,b],{a,-1/2,1/2},{b,-1/2,1/2}];

Plot3D[sol12[a,b],{a,-1/2,1/2},{b,-1/2,1/2}];


Bob Hanlon

---- "T.Sariyski" <tsariysk at verizon.net> wrote: 
> Hi,
> I have an output from a Solve that returns a solution as a list of 
> rules. Each branch of the solution is a two-parametric function e.g.
> 
> {{ x -> Something(a,b),  y->Something(a,b)},...
> 
> I want to plot a specific branch of the solution with Plot3D as a 
> function of {a,b}. I tried to assign a solution branch to a function 
> sol11[a,b]
> 
> sol11[a_,b_]=%[[1,1]]
> 
> and to plot sol11 but it doesn't work. How can I access a parametric 
> solution as returned from Solve as  a function of it's parameters?
> 
> Thanks, Ted


  • Prev by Date: Re: please explain why numerical integration is attempted
  • Next by Date: Re: please explain why numerical integration is attempted for this input
  • Previous by thread: Re: A pattern matching problem
  • Next by thread: Re: [TS 48]--Re:why isn't Rational[1,2] (apparently) atomic until it is evaluated?