Hi!

I'm trying to fit a model with 3 ODEs and 7 parameters to a dataset using GlobalSolve as shown in the code pasted below. Unfortunately, after fitting for approximately 10000s I get the error message:                 System error, , "PopErrorProc"

I tried to find out more about this error message on the internet but I only found that a system error indicates an internal Maple bug.

My first question is: is that true for all system errors, that it is an internal maple bug?

The second question is: is there something I can do to prevent or work around this problem?

All help is very much appreciated.

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CODE:

DiffSol:= proc(L,B,DT,DI,K,P,DV)
  local S, SoST, SoSV, j, e8, VL: 
  try for j from 1 to NbrT do
        Tvar(parameters=[L,B,DT,DI,K,P,DV]);
        SoST:=SoST+((Tvar(T_Time[i][j]))-CDdata[i][j])^2;   od: 
      for j from 1 to NbrV do
        Vvar(parameters=[L,B,DT,DI,K,P,DV,e8]); 
        SoSV:=SoSV+(Vvar(S_Time[i][j])-Vdata[i][j])^2:  od: 
      S:=SoST+SoSV:
  catch:  S:=999: error finally return(S)
  end try;
end proc:


#3ODE model
eqnT:=-diff(T(t),t)+lambda-beta*T(t)*V(t)-delta_T*T(t):
eqnTs:=-diff(Ts(t),t)+beta*T(t)*V(t)-delta_I*Ts(t)-k*Ts(t)*E8:
eqnV:=-diff(V(t),t)+p*Ts(t)-delta_V*V(t):

for i from 1 to 5 do
  initialCon:=T(0)=8,Ts(0)=0,V(0)=4.6:
  Linit:=Cfit[3][i]: Binit:=Cfit[4][i]: DTinit:=Cfit[5][i]: DIinit:=Cfit[6][i]: Kinit:=Cfit[8][i]: Pinit:=Cfit[9][i]: DVinit:=Cfit[7][i]:

  dsol:=dsolve({eqnT,eqnTs,eqnV,initialCon},{T(t), Ts(t), V(t)},numeric,output=listprocedure,parameters=[lambda,beta,delta_T,delta_I,k,p,delta_V,E8]);
  Tvar:=subs(dsol,T(t)+Ts(t));
  Vvar:=subs(dsol,V(t)); 

  try  print(GlobalSolve('DiffSol'(L,B,DT,DI,K,P,DV),L=1..1000,B=1e-8..0.01,DT=0.01..0.1,DI=0..1.3,K=0..1.3,P=220..50000,DV=3..200,timelimit=15000,initialpoint={L=Linit,B=Binit,DT=DTinit,DI=DIinit,K=Kinit,P=Pinit,DV=DVinit}, method=singlestart) )
  catch:  print(E)  end try;
od:



                       System error, , "PopErrorProc"