MathGroup Archive 1997

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

Search the Archive

Iterating NDSolve


Can anyone help?  I set up a system of two equations after defining the
expressions f and g.  NDSolve[{t'[v]==g, t[0]==10000,x'[v]==f,
x[0]==0,{t,x},{v,0,20}]

The problem is, both f and g also depend on a parameter that
I call theta (theta actually represents a chemical concentration, this is
a kinetics problem). I can simply vary theta in my definition of f and g
and solve the equations several times to see how solution varies with
theta. I did this (by rewriting the input for theta and the NDsolve
command about 50 times to vary theta from 0 to 50). I can then evaluate
x[v] at several values of v for each theta and make a list for each theta
and apply the function ListPlot3D.  This is very inefficient way to graph
x[v,theta].  Is there a simple way to do this in 3 or 4 command lines.  

I'd like in general to numerically solve ODE's and then plot results as
function of two variables.  (Is it possible to define a function of the
variable theta as the solution to the NDSolve command?  When I try to do
this I get error message.).  Any help would be greatly appreciated. 


  • Prev by Date: Re: question
  • Next by Date: Re: question
  • Previous by thread: Re: Complete Factorization?
  • Next by thread: Re: Iterating NDSolve