interpolating function as initial condition

*To*: mathgroup at smc.vnet.net*Subject*: [mg102804] interpolating function as initial condition*From*: venkat reddy <vemkatma at gmail.com>*Date*: Thu, 27 Aug 2009 06:37:58 -0400 (EDT)

* hi all, I am relatively new to mathematica. I am trying to solve 4 couples pdes in which one is second order pde. What I like to do is solve the equation for some time span(like t=0 to t=tfinal) with some arbitray initial conditions(e.g. cf[0,z]=tf[0,z]=something). I get solution for my 4 dependent variables(cf,tf,cc,tc) in terms of interpolated functions. I want to use these interpolated functions as initial condition(like cf[o,z]=InterpolatingFunction for cf at tfinal) for further calculations= . I have trouble in using the interpolating function as initial condition. Please can some body help me out. Thank you. here is the code for your reference sol=NDSolve[ { D[cf[t,z],t]+v D[cf[t,z],z]-a1 (cc[t,z]-cf[t,z])=C5 0, D[tf[t,z],t]+v D[tf[t,z],z]-a2 (tc[t,z]-tf[t,z])-a3 (tw-tf[t,z])=C5 0, D[cc[t,z],t]-a4 (cf[t,z]-cc[t,z])-a5 r[cc[t,z],tc[t,z]]=C5 0, D[tc[t,z],t]-a6 (tf[t,z]-tc[t,z])-a7 r[cc[t,z],tc[t,z]]-a8 D[tc[t,z],z,z]= =C5 0, cf[t,0]=C5 c0,tf[t,0]=C5 t0,(D[tc[t,z],z]/.z=C2=AE0)=C5 0,(D[tc[t,z],= z]/.z=C2=AElength)=C5 0, cf[0,z]=C5 c0,tf[0,z]=C5 t0,cc[0,z]=C5 c0,tc[0,z]=C5 t0 }, {cf,tf,cc,tc},{t,0,tfinal}, {z,0,length} ] {{cf=C2=AEInterpolatingFunction[{{0.,10000.},{0.,1.}},<>], tf=C2=AEInterpolatingFunction[{{0.,10000.},{0.,1.}},<>], cc=C2=AEInterpolatingFunction[{{0.,10000.},{0.,1.}},<>], tc=C2=AEInterpolatingFunction[{{0.,10000.},{0.,1.}},<>]}} *