Beispiel #1
0
  void IpoptAlgorithm::calc_number_of_bounds(
    const Vector& x,
    const Vector& x_L,
    const Vector& x_U,
    const Matrix& Px_L,
    const Matrix& Px_U,
    Index& n_tot,
    Index& n_only_lower,
    Index& n_both,
    Index& n_only_upper)
  {
    DBG_START_METH("IpoptAlgorithm::calc_number_of_bounds",
                   dbg_verbosity);

    n_tot = x.Dim();

    SmartPtr<Vector> tmpx = x.MakeNew();
    SmartPtr<Vector> tmpxL = x_L.MakeNew();
    SmartPtr<Vector> tmpxU = x_U.MakeNew();

    tmpxL->Set(-1.);
    tmpxU->Set(2.);
    Px_L.MultVector(1.0, *tmpxL, 0.0, *tmpx);
    Px_U.MultVector(1.0, *tmpxU, 1.0, *tmpx);
    // Now, x has elements
    //  -1 : if component has only lower bound
    //   0 : if component has no bound
    //   1 : if component has both lower and upper bound
    //   2 : if component has only upper bound
    DBG_PRINT_VECTOR(2, "x-indicator", *tmpx);

    SmartPtr<Vector> tmpx0 = x.MakeNew();
    tmpx0->Set(0.);

    SmartPtr<Vector> tmpx2 = x.MakeNew();
    tmpx2->Set(-1.0);
    tmpx2->Axpy(1.0, *tmpx);
    tmpx2->ElementWiseMax(*tmpx0); // tmpx2 is now 1 in those
    // components with only upper bounds
    n_only_upper = (Index)tmpx2->Asum();

    tmpx->Axpy(-2., *tmpx2);       // now make all those entries for
    // only upper bounds zero in tmpx

    tmpx2->Copy(*tmpx);
    tmpx2->ElementWiseMax(*tmpx0); // tmpx2 is now 1 in those
    // components with both bounds
    n_both = (Index)tmpx2->Asum();

    tmpx->Axpy(-1., *tmpx2);
    tmpx->ElementWiseMin(*tmpx);   // tmpx is now -1 in those with only
    // lower bounds
    n_only_lower = (Index)tmpx->Asum();

  }
Beispiel #2
0
  void GradientScaling::DetermineScalingParametersImpl(
    const SmartPtr<const VectorSpace> x_space,
    const SmartPtr<const VectorSpace> p_space,
    const SmartPtr<const VectorSpace> c_space,
    const SmartPtr<const VectorSpace> d_space,
    const SmartPtr<const MatrixSpace> jac_c_space,
    const SmartPtr<const MatrixSpace> jac_d_space,
    const SmartPtr<const SymMatrixSpace> h_space,
    const Matrix& Px_L, const Vector& x_L,
    const Matrix& Px_U, const Vector& x_U,
    Number& df,
    SmartPtr<Vector>& dx,
    SmartPtr<Vector>& dc,
    SmartPtr<Vector>& dd)
  {
    DBG_ASSERT(IsValid(nlp_));

    SmartPtr<Vector> x = x_space->MakeNew();
    SmartPtr<Vector> p = p_space->MakeNew();
    if (!nlp_->GetStartingPoint(GetRawPtr(x), true,
				GetRawPtr(p), true,
                                NULL, false,
                                NULL, false,
                                NULL, false,
                                NULL, false)) {
      THROW_EXCEPTION(FAILED_INITIALIZATION,
                      "Error getting initial point from NLP in GradientScaling.\n");
    }

    //
    // Calculate grad_f scaling
    //
    SmartPtr<Vector> grad_f = x_space->MakeNew();
    if (nlp_->Eval_grad_f(*x, *p, *grad_f)) {
      double max_grad_f = grad_f->Amax();
      df = 1.;
      if (scaling_obj_target_gradient_ == 0.) {
        if (max_grad_f > scaling_max_gradient_) {
          df = scaling_max_gradient_ / max_grad_f;
        }
      }
      else {
        if (max_grad_f == 0.) {
          Jnlst().Printf(J_WARNING, J_INITIALIZATION,
                         "Gradient of objective function is zero at starting point.  Cannot determine scaling factor based on scaling_obj_target_gradient option.\n");
        }
        else {
          df = scaling_obj_target_gradient_ / max_grad_f;
        }
      }
      df = Max(df, scaling_min_value_);
      Jnlst().Printf(J_DETAILED, J_INITIALIZATION,
                     "Scaling parameter for objective function = %e\n", df);
    }
    else {
      Jnlst().Printf(J_WARNING, J_INITIALIZATION,
                     "Error evaluating objective gradient at user provided starting point.\n  No scaling factor for objective function computed!\n");
      df = 1.;
    }
    //
    // No x scaling
    //
    dx = NULL;

    dc = NULL;
    if (c_space->Dim()>0) {
      //
      // Calculate c scaling
      //
      SmartPtr<Matrix> jac_c = jac_c_space->MakeNew();
      if (nlp_->Eval_jac_c(*x, *p, *jac_c)) {
        dc = c_space->MakeNew();
        const double dbl_min = std::numeric_limits<double>::min();
        dc->Set(dbl_min);
        jac_c->ComputeRowAMax(*dc, false);
        Number arow_max = dc->Amax();
        if (scaling_constr_target_gradient_<=0.) {
          if (arow_max > scaling_max_gradient_) {
            dc->ElementWiseReciprocal();
            dc->Scal(scaling_max_gradient_);
            SmartPtr<Vector> dummy = dc->MakeNew();
            dummy->Set(1.);
            dc->ElementWiseMin(*dummy);
          }
          else {
            dc = NULL;
          }
        }
        else {
          dc->Set(scaling_constr_target_gradient_/arow_max);
        }
        if (IsValid(dc) && scaling_min_value_ > 0.) {
          SmartPtr<Vector> tmp = dc->MakeNew();
          tmp->Set(scaling_min_value_);
          dc->ElementWiseMax(*tmp);
        }
      }
      else {
        Jnlst().Printf(J_WARNING, J_INITIALIZATION,
                       "Error evaluating Jacobian of equality constraints at user provided starting point.\n  No scaling factors for equality constraints computed!\n");
      }
    }

    dd = NULL;
    if (d_space->Dim()>0) {
      //
      // Calculate d scaling
      //
      SmartPtr<Matrix> jac_d = jac_d_space->MakeNew();
      if (nlp_->Eval_jac_d(*x, *p, *jac_d)) {
        dd = d_space->MakeNew();
        const double dbl_min = std::numeric_limits<double>::min();
        dd->Set(dbl_min);
        jac_d->ComputeRowAMax(*dd, false);
        Number arow_max = dd->Amax();
        if (scaling_constr_target_gradient_<=0.) {
          if (arow_max > scaling_max_gradient_) {
            dd->ElementWiseReciprocal();
            dd->Scal(scaling_max_gradient_);
            SmartPtr<Vector> dummy = dd->MakeNew();
            dummy->Set(1.);
            dd->ElementWiseMin(*dummy);
          }
          else {
            dd = NULL;
          }
        }
        else {
          dd->Set(scaling_constr_target_gradient_/arow_max);
        }
        if (IsValid(dd) && scaling_min_value_ > 0.) {
          SmartPtr<Vector> tmp = dd->MakeNew();
          tmp->Set(scaling_min_value_);
          dd->ElementWiseMax(*tmp);
        }
      }
      else {
        Jnlst().Printf(J_WARNING, J_INITIALIZATION,
                       "Error evaluating Jacobian of inequality constraints at user provided starting point.\n  No scaling factors for inequality constraints computed!\n");
      }
    }
  }