Services & Resources / Wolfram Forums / MathGroup Archive

MathGroup Archive 2010

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

Search the Archive

ODE solution transfer

  • To: mathgroup at
  • Subject: [mg111419] ODE solution transfer
  • From: EF <he.frauendorfer at>
  • Date: Sat, 31 Jul 2010 02:42:57 -0400 (EDT)


  for the following sample ODE with the variables a[t] and b[t]

  deqns={a'[t]== -k*a[t], a[0]==2,
         b'[t]==  k*a[t], b[0]==0};

  the lists  vars  = {a[t],b[t]}
  and        fvars = {a[t_],b[t_]} are declared.


   gives the function values for a[t] and b[t], e.g. a[5] = 1.3406


  gives no function values for a[t] and b[t], entering a[5] returns
  no numeric value. fvars can be plotted however.

  The Full Forms of the corresponding expressions show no differences.
  I tried Thread, Map, Apply, Set @@@  etc without result.
  For ODEs with more than 100 variables, a form like fvars
  generated from vars would be useful.

  Please suggest a fix, Thanks


  • Prev by Date: Re: different results for Standard vs Prefix forms
  • Next by Date: Re: NDSolve - how to bypass safety chceck?
  • Previous by thread: importing 3D-data from STEP file
  • Next by thread: Re: How export/recompile expressions and calculation code to run