[Ipopt] question about the get_starting_point() function

[刘全昌]

hello everybody,
    I have a question about the get_starting_point function.  I computed a value which used in my application in this function. The value depended to the starting points of the Ipopt algorithm. I used to think that the agorithm should enter the get_starting_point function once, and then I could get the value I wanted in the finalize_solution function.
    However, I got a wrong result of the value in the  finalize_solution function. I am very worried about the result because it is really a very simple procedure. I used the GDB to debug the program, then I found that the algorithm entered the get_starting_point function  twice!!! The first time when the algorithm entered the get_starting_point function , I got the right result. The second time , I got the wrong result.
    My question is why the Ipopt algorithm would enter the get_starting_point  function  more than one time? What's the purpose of this ? Thank you for any suggestions!!
                                                                         Regard
                                                                                    LiuQuanchang.
The C++ codes of the get_starting_point function are as followings:
bool reatvOptSolver::get_starting_point(Index n, bool init_x, Number* x, bool init_z, Number* z_L, Number* z_U, Index m, bool init_lambda, Number* lambda)
{
     for (int i=0;i<pqnodeN;i++)
   {
       x[2*i] = vroAlgData.nodevalue[i].vlu;
    x[2*i+1] = vroAlgData.nodevalue[i].theta;
   }
   
    for (int i=0;i<pvnodeN;i++)
   {
    x[2*pqnodeN+i]= vroAlgData.nodevalue[i+pqnodeN].theta;
    }
 
  Number obj_value;
 obj_value = pow(blnV,2)*Gii(nodenum-1);
 
 for (int i=0;i<nodenum-1;i++)
 {
  
  if (i<pqnodeN)
  {
   obj_value += 2*blnV*x[2*i]*Gij(nodenum-1,i)*cos(blnTheta-x[2*i+1]);
   
  }else
  {  
   obj_value += 2*blnV*vroAlgData.nodevalue[i].vlu*Gij(nodenum-1,i)*cos(blnTheta-x[i+pqnodeN]);
   
  }
  
  for (int j=0;j<nodenum-1;j++)
  {
   
   if (j<pqnodeN)
   {
    if (i<pqnodeN)
    {
     obj_value += x[2*i]*x[2*j]*Gij(i,j)*cos(x[2*i+1]-x[2*j+1]);
    }
    else
    {
     obj_value += vroAlgData.nodevalue[i].vlu*x[2*j]*Gij(i,j)*cos(x[i+pqnodeN]-x[2*j+1]);
    }
   }else
   {  
    if (i<pqnodeN)
    {
     obj_value += x[2*i]*vroAlgData.nodevalue[j].vlu*Gij(i,j)*cos(x[2*i+1]-x[j+pqnodeN]);
    }
    else
    {
     obj_value += vroAlgData.nodevalue[i].vlu*vroAlgData.nodevalue[j].vlu*Gij(i,j)*cos(x[i+pqnodeN]-x[j+pqnodeN]);
    }
   }
  }
 }
 iterinfo->vroInitPLoss = obj_value;
 
 return true;
}
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