inv_reduced_hessian_barrier

(function from pyomo.contrib.interior_point.inverse_reduced_hessian)

pyomo.contrib.interior_point.inverse_reduced_hessian.inv_reduced_hessian_barrier(model, independent_variables, bound_tolerance=1e-06, solver_options=None, tee=False)[source]

This function computes the inverse of the reduced Hessian of a problem at the solution. This function first solves the problem with Ipopt and then generates the KKT system for the barrier subproblem to compute the inverse reduced hessian.

For more information on the reduced Hessian, see “Numerical Optimization”, 2nd Edition Nocedal and Wright, 2006.

The approach used in this method can be found in, “Computational Strategies for the Optimal Operation of Large-Scale Chemical Processes”, Dissertation, V. Zavala 2008. See section 3.2.1.

Parameters:
  • model (Pyomo model) – The Pyomo model that we want to solve and analyze

  • independent_variables (list of Pyomo variables) – This is the list of independent variables for computing the reduced hessian. These variables must not be at their bounds at the solution of the optimization problem.

  • bound_tolerance (float) – The tolerance to use when checking if the variables are too close to their bound. If they are too close, then the routine will exit without a reduced hessian.

  • solver_options (dictionary) – Additional solver options to consider.

  • tee (bool) – This flag is sent to the tee option of the solver. If true, then the solver log is output to the console.