Question: pdsolve:-plot changes the initial profile of the function at t=0...

This is the eq I am trying to solve

pde1:= diff(Phi(r,t),t,t) = (-(diff(Phi(r, t), r, r))*r^2-2*(diff(Phi(r, t), r))*r+2*(diff(Phi(r, t), r))^2+4*(diff(Phi(r, t), r))*(diff(Phi(r, t), r, r))*r+2*(diff(Phi(r, t), t, r))^2*r^2)/(r*(-r+2*r*(diff(Phi(r, t), r, r))+4*(diff(Phi(r, t), r))));

with initial conditions..



pdsolve runs and returns the module..

pds1:=pdsolve(pde1,IC,numeric,time=t,range=0..z); -> this runs without problems!

BUT WHEN I TRY TO PLOT.. AGAIN NO ERROR MESSAGES BUT!! THE AT T=0 THE Phi(r,0) is not the plot of the function I gave as initial condition.. the plot at t=0 obviously should be the same plot as the function "Piinitial"

But the plot is different everytime I change the range z??


Can some one please help!!! Thanks?

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