Originally posted by: Dmartinc

Hello,

I´am trying to solve a VRP with satellite depots, until now I just write my model in source code, when I try to execute it, I have this problem:

Empty Handle in IloArray::operator[]
Assertation failed::(_impl)||(ILOSTD(cerr)<<"Empty handle in IloArray::operator[]"<< ILOSTD(endl), ilo_stop_assert()), file: iloenv.h

What does it mean?

I add my source code, thanks.

#include <ilcplex/ilocplex.h>

ILOSTLBEGIN

typedef IloArray<IloNumArray> NumMatrix; //numbers matrix
typedef IloArray<IloBoolVarArray> BoolVarMatrix; //variables matrix

// VRP-Satellite Depots

int main(int argc, char** argv) {

IloEnv env;
try {

IloInt i,j,l,m,k;

IloModel modelo(env);

IloInt V1,V2,Vd,Vc;

Vc=4;
Vd=2;

/*ifstream archivo("data.csv");

archivo >> Vc;
archivo.get();
cout << "Numero de clientes:" << Vc << endl;
archivo >> Vd;
archivo.get();
cout << "Numero de almacenes:" << Vd << endl;*/

IloNumVarArray V(env,Vd,2,IloInfinity);

V1=Vd+1;
V2=Vc+Vd;
for(i=0;i<Vd;i++)
{
V[i]==Vc+i;
}

//decision variable y[i][j]
BoolVarMatrix y(env, V1);
for(i = 0; i < Vd; i++)
{
y[i] = IloBoolVarArray(env, V1);
for(int j=0; j<V1;++j){
stringstream nn;
nn << "y(" << 1+i << " " <<1+j << ")";
y[i][j].setName( nn.str().c_str() );
}
}
//decision variable x[l][m][j]
IloArray<IloArray<IloBoolVarArray>> x(env, V2);
for(l = 0; l < V2; l++)
{
x[l] = IloArray<IloBoolVarArray>(env, V2);
for(m = 0; m < V2; m++)
{
x[l][m] = IloBoolVarArray(env, Vd);
for(int j=0; j<Vd;++j)
{
stringstream ss;
ss << "x(" <<1+l<< " " <<1+m<< " " <<1+j<< ")";
x[l][m][j].setName( ss.str().c_str() );
}
}
}

//leangth of first-level trip

NumMatrix c(env, V1);

for(i = 0; i < V1; i++)
{
c[i] = IloNumArray(env, V1);

}

c[0][0]=0.00;
c[0][1]=2.83;
c[0][2]=4.47;
c[1][0]=2.83;
c[1][1]=0.00;
c[1][2]=2.00;
c[2][0]=4.47;
c[2][1]=2.00;
c[2][2]=0.00;
//Creates matrix of first-level trip

NumMatrix g(env, V2);

for(l = 0; l < V2; l++)
{
g[l] = IloNumArray(env, V2);

}

g[0][0]=0.00;
g[0][1]=2.00;
g[0][2]=1.00;
g[0][3]=4.00;
g[0][4]=5.00;
g[0][5]=3.00;
g[1][0]=2.00;
g[1][1]=0.00;
g[1][2]=2.00;
g[1][3]=4.00;
g[1][4]=2.00;
g[1][5]=6.00;
g[2][0]=1.00;
g[2][1]=2.00;
g[2][2]=0.00;
g[2][3]=2.00;
g[2][4]=6.00;
g[2][5]=4.50;
g[3][0]=4.00;
g[3][1]=4.00;
g[3][2]=2.00;
g[3][3]=0.00;
g[3][4]=5.00;
g[3][5]=6.00;
g[4][0]=5.00;
g[4][1]=2.00;
g[4][2]=6.00;
g[4][3]=5.00;
g[4][4]=0.00;
g[4][5]=5.50;
g[5][0]=3.00;
g[5][1]=6.00;
g[5][2]=4.50;
g[5][3]=6.00;
g[5][4]=5.50;
g[5][5]=0.00;
//sets leangth matrix for first-level trip

/* for (int i=0;i<V1;i++)
{
for(int j=0;j<V1;j++)
{
archivo >> c[i][j];
archivo.get();
}
}*/

cout << "vector c:" << c << endl <<endl;

//sets leangth matrix for second-level trip

/* ifstream archivo1("data1.csv");
for (int l=0;l<V2;l++)
{
for(int m=0;m<V2;m++)
{
archivo >> g[l][m];
archivo.get();
}
}*/

cout << "vector g:" << g << endl <<endl;
//Objetive Function

IloExpr fo1(env);
IloExpr fo2(env);
IloExpr fo(env);

for ( i = 0; i < V1; ++i)
{
for ( j = 0; j < V1; ++j)
fo1 += c[i][j]*y[i][j];
}
for ( j = 0; j < Vd; ++j)
{
for ( l = 0; j < V2; ++l)
{
for ( m = 0; m < V2; ++m)
fo2 += g[l][m]*x[l][m][j];
}
}
fo=fo1+fo2;
modelo.add(IloMinimize(env, fo));
fo1.end();
fo2.end();
fo.end();
//A trailer point is visited at most once in the first-level trip

for(j = 0; j < Vd; ++j)
{
IloExpr Expr0(env);
for(i = 0; i < V1; ++i)
{
if(i!=j)
Expr0 = Expr0 + y[i][j];
}
modelo.add(Expr0 <= 1 );
Expr0.end();
}

for(j = 0; j < Vd; ++j)
{
IloExpr Expr1(env);
for(i = 0; i < V1; ++i)
{
if(i!=j)
Expr1 = Expr1 + y[j][i];
}
modelo.add(Expr1 <= 1 );
Expr1.end();
}

//Connectivity constraints for the first-level trip
for(j = 0; j < Vd; j++)
{
IloExpr Expr2(env);
IloExpr Expr3(env);
for(i = 0; i < V1; ++i)
{
Expr2 = Expr2 + y[i][j];
}
for(k = 0; k < V1; ++k)
{
Expr3 = Expr3 + y[j][k];
}
modelo.add(Expr2 == Expr3);
Expr2.end();
Expr3.end();
}

//the first level trip departs and ends at the main depot

IloExpr Expr4(env);
for(i = 0; i < Vd; ++i)
{
Expr4 = Expr4 + y[i][0];
}
modelo.add(Expr4 == 1 );
Expr4.end();

IloExpr Expr5(env);
for(j = 0; j < Vd; ++j)
{
Expr5 = Expr5 + y[0][j];
}
modelo.add(Expr5 == 1 );
Expr5.end();

//Subtour elimination
/*for( l = 0; l < ; ++l)
for(i = 0; i < V[l]; ++i)
{
IloExpr Expr6(env);
for(j = 0; j < V[l]; ++j)
{
Expr6 = Expr6 + y[i][j];
}
modelo.add(Expr6 <= V[l]-1 );
Expr6.end();
}*/

//Second level trips departs only from trailer points visited in the first level

for ( j = 0; j < Vd; ++j)
{
IloExpr Expr7(env);
IloExpr Expr8(env);
for ( i = 0; i < V1; ++j)
{
Expr7 = Expr7 + y[i][j];
}
for ( l = 0; l < Vd; ++l)
{
for ( m = 0; m < Vd; ++m)
Expr8 = x[l][m][j];
}
modelo.add(Expr8 <= Expr7);
Expr7.end();
Expr8.end();

}
//Each constumer must be visited exactly once

for ( m = 0; m < Vc; ++m)
{
IloExpr Expr9(env);
for ( l = 0; l < V2; ++l)
{
for ( j = 0; j < Vd; ++j)
Expr9 = Expr9 + x[l][m][j];
}
modelo.add(Expr9 == 1);
Expr9.end();

}

//Guarantee the connectivity of second level trips
for( j = 0; j < Vd; j++)
{
IloExpr Expr10(env);
IloExpr Expr11(env);
for(m = 0; m < Vc; ++m)
{
for(l = 0; l < V2; ++l)
Expr10 = Expr10 + x[l][m][j];
for(k = 0; k < V2; ++k)
Expr11 = Expr11 + x[m][k][j];
}
modelo.add(Expr10 - Expr11 == 0);
Expr10.end();
Expr11.end();
}

//All second level trips departing from trailer point return to it
for(j = 0; j < Vd; j++)
{
IloExpr Expr12(env);
IloExpr Expr13(env);
for(l = 0; l < Vc; ++l)
for(k = 0; k < Vc; ++k)
Expr12 = Expr12 + x[j][l][j];
Expr13 = Expr13 + x[k][j][j];
modelo.add(Expr12 - Expr13 == 0);
Expr12.end();
Expr13.end();
}

//Prevents subtours in second level trips
/* for( i=0; i< ; i++)
for(j = 0; j < Vd; j++)
{
IloExpr Expr14(env);
for(l = 0; l < V[i]; ++l)
for(m = 0; m < V[i]; ++m)
Expr14 = Expr14 + x[l][m][j];
modelo.add(Expr14 <= V[i] - s*V[i]);
Expr14.end();
}
*/

IloCplex cplex(env);
cplex.extract(modelo);
cplex.exportModel("VRPSD.lp");
cplex.solve();

if ( !cplex.solve() ) {
env.error() << "It couldn´t solve it :-(" << endl;
throw ( -1 );
}

env.out() << "Is it optimal ? = " << cplex.getStatus() << endl;
env.out() << "Time solve = " << env.getTime() << endl;
env.out() << " - Solution first level trip:" << endl;
for(i = 0; i < V1; i++)
{
env.out() <<" "<<i<<":";

for(j = 0; j < V1; j++)
{
env.out() <<cplex.getValue(y[i][j])<<"\t";
}
env.out() << endl;
}
env.out() << " - Solution second level trip:" << endl;
for(j = 0; j < Vd; j++)
{
env.out() <<" "<<i<<":";
for(l = 0; l < V2; l++)
for(m = 0; m < V2; m++)
env.out() <<cplex.getValue(x[l][m][j])<<"\t";
env.out() << endl;
}

env.out() << " Minimal leangth = " << cplex.getObjValue() << endl;

}
catch (IloException& e) {
cerr << "ERROR: " << e.getMessage() << endl;
}
catch (...) {
cerr << "Error" << endl;
}
env.end();

char c = getchar();
return 0;
}
#CPLEXOptimizers
#DecisionOptimization

Originally posted by: SystemAdmin

Before you post lengthy code like yours please try to condense it to isolate the problem.
Your problem is your usage of the matrix 'y'. You initialize this matrix to be a Vd x V1 matrix

BoolVarMatrix y(env, V1);
      for(i = 0; i < Vd; i++)
      {
         y[i] = IloBoolVarArray(env, V1);
         for(int j=0; j<V1;++j){
            stringstream nn;
            nn << "y(" << 1+i << " " <<1+j << ")";
            y[i][j].setName( nn.str().c_str() );
         }
      }

but use it as if it was a V1 x V1 matrix:

for ( i = 0; i < V1; ++i)
      {
         for ( j = 0; j < V1; ++j)
            fo1 += c[i][j]*y[i][j];
      }

Since V1=Vd+1 in your code this means that you eventually access a non-existing element in y which then throws the assertion.
#CPLEXOptimizers
#DecisionOptimization

Originally posted by: Dmartinc

Firstly, thank you for your answer.

I was thinking more deeply in the problem and my conclusion was that, I was trying to access in array without non-existing elements. I´am going to fix it, and I hope to run a first instance of my VRP.
Thank you
#CPLEXOptimizers
#DecisionOptimization

Originally posted by: lorafrance

fds

#CPLEXOptimizers
#DecisionOptimization