def get_infeasible_result_object(model, message=""): infeas_result = SubproblemResult() infeas_result.feasible = False infeas_result.var_values = list(v.value for v in model.GDPopt_utils.variable_list) infeas_result.pyomo_results = SolverResults() infeas_result.pyomo_results.solver.termination_condition = tc.infeasible infeas_result.pyomo_results.message = message infeas_result.dual_values = list(None for _ in model.GDPopt_utils.constraint_list) return infeas_result
def solve_linear_subproblem(mip_model, solve_data, config): GDPopt = mip_model.GDPopt_utils initialize_subproblem(mip_model, solve_data) # Callback immediately before solving NLP subproblem config.call_before_subproblem_solve(mip_model, solve_data) mip_solver = SolverFactory(config.mip_solver) if not mip_solver.available(): raise RuntimeError("MIP solver %s is not available." % config.mip_solver) with SuppressInfeasibleWarning(): mip_args = dict(config.mip_solver_args) elapsed = get_main_elapsed_time(solve_data.timing) remaining = max(config.time_limit - elapsed, 1) if config.mip_solver == 'gams': mip_args['add_options'] = mip_args.get('add_options', []) mip_args['add_options'].append('option reslim=%s;' % remaining) elif config.mip_solver == 'multisolve': mip_args['time_limit'] = min( mip_args.get('time_limit', float('inf')), remaining) results = mip_solver.solve(mip_model, **mip_args) subprob_result = SubproblemResult() subprob_result.feasible = True subprob_result.var_values = list(v.value for v in GDPopt.variable_list) subprob_result.pyomo_results = results subprob_result.dual_values = list( mip_model.dual.get(c, None) for c in GDPopt.constraint_list) subprob_terminate_cond = results.solver.termination_condition if subprob_terminate_cond is tc.optimal: pass elif subprob_terminate_cond is tc.infeasible: config.logger.info('MIP subproblem was infeasible.') subprob_result.feasible = False else: raise ValueError('GDPopt unable to handle MIP subproblem termination ' 'condition of %s. Results: %s' % (subprob_terminate_cond, results)) # Call the NLP post-solve callback config.call_after_subproblem_solve(mip_model, solve_data) # if feasible, call the NLP post-feasible callback if subprob_result.feasible: config.call_after_subproblem_feasible(mip_model, solve_data) return subprob_result
def solve_linear_subproblem(mip_model, solve_data, config): GDPopt = mip_model.GDPopt_utils initialize_subproblem(mip_model, solve_data) # Callback immediately before solving NLP subproblem config.call_before_subproblem_solve(mip_model, solve_data) mip_solver = SolverFactory(config.mip_solver) if not mip_solver.available(): raise RuntimeError("MIP solver %s is not available." % config.mip_solver) with SuppressInfeasibleWarning(): results = mip_solver.solve(mip_model, **config.mip_solver_args) subprob_result = SubproblemResult() subprob_result.feasible = True subprob_result.var_values = list(v.value for v in GDPopt.variable_list) subprob_result.pyomo_results = results subprob_result.dual_values = list( mip_model.dual.get(c, None) for c in GDPopt.constraint_list) subprob_terminate_cond = results.solver.termination_condition if subprob_terminate_cond is tc.optimal: pass elif subprob_terminate_cond is tc.infeasible: config.logger.info('MIP subproblem was infeasible.') subprob_result.feasible = False else: raise ValueError('GDPopt unable to handle MIP subproblem termination ' 'condition of %s. Results: %s' % (subprob_terminate_cond, results)) # Call the NLP post-solve callback config.call_after_subproblem_solve(mip_model, solve_data) # if feasible, call the NLP post-feasible callback if subprob_result.feasible: config.call_after_subproblem_feasible(mip_model, solve_data) return subprob_result
def solve_NLP(nlp_model, solve_data, config): """Solve the NLP subproblem.""" config.logger.info('Solving nonlinear subproblem for ' 'fixed binaries and logical realizations.') # Error checking for unfixed discrete variables unfixed_discrete_vars = detect_unfixed_discrete_vars(nlp_model) assert len(unfixed_discrete_vars) == 0, \ "Unfixed discrete variables exist on the NLP subproblem: {0}".format( list(v.name for v in unfixed_discrete_vars)) GDPopt = nlp_model.GDPopt_utils initialize_subproblem(nlp_model, solve_data) # Callback immediately before solving NLP subproblem config.call_before_subproblem_solve(nlp_model, solve_data) nlp_solver = SolverFactory(config.nlp_solver) if not nlp_solver.available(): raise RuntimeError("NLP solver %s is not available." % config.nlp_solver) with SuppressInfeasibleWarning(): try: results = nlp_solver.solve(nlp_model, **config.nlp_solver_args) except ValueError as err: if 'Cannot load SolverResults object with bad status: error' in str( err): results = SolverResults() results.solver.termination_condition = tc.error results.solver.message = str(err) else: raise nlp_result = SubproblemResult() nlp_result.feasible = True nlp_result.var_values = list(v.value for v in GDPopt.variable_list) nlp_result.pyomo_results = results nlp_result.dual_values = list( nlp_model.dual.get(c, None) for c in GDPopt.constraint_list) term_cond = results.solver.termination_condition if any(term_cond == cond for cond in (tc.optimal, tc.locallyOptimal, tc.feasible)): pass elif term_cond == tc.infeasible: config.logger.info('NLP subproblem was infeasible.') nlp_result.feasible = False elif term_cond == tc.maxIterations: # TODO try something else? Reinitialize with different initial # value? config.logger.info( 'NLP subproblem failed to converge within iteration limit.') if is_feasible(nlp_model, config): config.logger.info( 'NLP solution is still feasible. ' 'Using potentially suboptimal feasible solution.') else: nlp_result.feasible = False elif term_cond == tc.internalSolverError: # Possible that IPOPT had a restoration failure config.logger.info("NLP solver had an internal failure: %s" % results.solver.message) nlp_result.feasible = False elif (term_cond == tc.other and "Too few degrees of freedom" in str(results.solver.message)): # Possible IPOPT degrees of freedom error config.logger.info("IPOPT has too few degrees of freedom: %s" % results.solver.message) nlp_result.feasible = False elif term_cond == tc.other: config.logger.info( "NLP solver had a termination condition of 'other': %s" % results.solver.message) nlp_result.feasible = False elif term_cond == tc.error: config.logger.info( "NLP solver had a termination condition of 'error': %s" % results.solver.message) nlp_result.feasible = False elif term_cond == tc.maxTimeLimit: config.logger.info( "NLP solver ran out of time. Assuming infeasible for now.") nlp_result.feasible = False else: raise ValueError('GDPopt unable to handle NLP subproblem termination ' 'condition of %s. Results: %s' % (term_cond, results)) # Call the NLP post-solve callback config.call_after_subproblem_solve(nlp_model, solve_data) # if feasible, call the NLP post-feasible callback if nlp_result.feasible: config.call_after_subproblem_feasible(nlp_model, solve_data) return nlp_result
def solve_MINLP(model, solve_data, config): """Solve the MINLP subproblem.""" config.logger.info( "Solving MINLP subproblem for fixed logical realizations.") GDPopt = model.GDPopt_utils initialize_subproblem(model, solve_data) # Callback immediately before solving MINLP subproblem config.call_before_subproblem_solve(model, solve_data) minlp_solver = SolverFactory(config.minlp_solver) if not minlp_solver.available(): raise RuntimeError("MINLP solver %s is not available." % config.minlp_solver) with SuppressInfeasibleWarning(): results = minlp_solver.solve(model, **config.minlp_solver_args) subprob_result = SubproblemResult() subprob_result.feasible = True subprob_result.var_values = list(v.value for v in GDPopt.variable_list) subprob_result.pyomo_results = results subprob_result.dual_values = list( model.dual.get(c, None) for c in GDPopt.constraint_list) term_cond = results.solver.termination_condition if any(term_cond == cond for cond in (tc.optimal, tc.locallyOptimal, tc.feasible)): pass elif term_cond == tc.infeasible: config.logger.info('MINLP subproblem was infeasible.') subprob_result.feasible = False elif term_cond == tc.maxIterations: # TODO try something else? Reinitialize with different initial # value? config.logger.info( 'MINLP subproblem failed to converge within iteration limit.') if is_feasible(model, config): config.logger.info( 'MINLP solution is still feasible. ' 'Using potentially suboptimal feasible solution.') else: subprob_result.feasible = False elif term_cond == tc.intermediateNonInteger: config.logger.info( "MINLP solver could not find feasible integer solution: %s" % results.solver.message) subprob_result.feasible = False else: raise ValueError( 'GDPopt unable to handle MINLP subproblem termination ' 'condition of %s. Results: %s' % (term_cond, results)) # Call the subproblem post-solve callback config.call_after_subproblem_solve(model, solve_data) # if feasible, call the subproblem post-feasible callback if subprob_result.feasible: config.call_after_subproblem_feasible(model, solve_data) return subprob_result
def solve_NLP(nlp_model, solve_data, config): """Solve the NLP subproblem.""" config.logger.info('Solving nonlinear subproblem for ' 'fixed binaries and logical realizations.') unfixed_discrete_vars = detect_unfixed_discrete_vars(nlp_model) if unfixed_discrete_vars: discrete_var_names = list(v.name for v in unfixed_discrete_vars) config.logger.warning( "Unfixed discrete variables exist on the NLP subproblem: %s" % (discrete_var_names, )) GDPopt = nlp_model.GDPopt_utils preprocessing_transformations = [ # Propagate variable bounds 'contrib.propagate_eq_var_bounds', # Detect fixed variables 'contrib.detect_fixed_vars', # Propagate fixed variables 'contrib.propagate_fixed_vars', # Remove zero terms in linear expressions 'contrib.remove_zero_terms', # Remove terms in equal to zero summations 'contrib.propagate_zero_sum', # Transform bound constraints 'contrib.constraints_to_var_bounds', # Detect fixed variables 'contrib.detect_fixed_vars', # Remove terms in equal to zero summations 'contrib.propagate_zero_sum', # Remove trivial constraints 'contrib.deactivate_trivial_constraints' ] for xfrm in preprocessing_transformations: TransformationFactory(xfrm).apply_to(nlp_model) initialize_NLP(nlp_model, solve_data) # Callback immediately before solving NLP subproblem config.call_before_subproblem_solve(nlp_model, solve_data) nlp_solver = SolverFactory(config.nlp_solver) if not nlp_solver.available(): raise RuntimeError("NLP solver %s is not available." % config.nlp_solver) with SuppressInfeasibleWarning(): results = nlp_solver.solve(nlp_model, **config.nlp_solver_args) nlp_result = SubproblemResult() nlp_result.feasible = True nlp_result.var_values = list(v.value for v in GDPopt.working_var_list) nlp_result.pyomo_results = results nlp_result.dual_values = list( nlp_model.dual.get(c, None) for c in GDPopt.working_constraints_list) subprob_terminate_cond = results.solver.termination_condition if subprob_terminate_cond is tc.optimal: pass elif subprob_terminate_cond is tc.infeasible: config.logger.info('NLP subproblem was locally infeasible.') nlp_result.feasible = False elif subprob_terminate_cond is tc.maxIterations: # TODO try something else? Reinitialize with different initial # value? config.logger.info( 'NLP subproblem failed to converge within iteration limit.') if is_feasible(nlp_model, config): config.logger.info( 'NLP solution is still feasible. ' 'Using potentially suboptimal feasible solution.') else: nlp_result.feasible = False elif subprob_terminate_cond is tc.internalSolverError: # Possible that IPOPT had a restoration failture config.logger.info("NLP solver had an internal failure: %s" % results.solver.message) nlp_result.feasible = False else: raise ValueError('GDPopt unable to handle NLP subproblem termination ' 'condition of %s. Results: %s' % (subprob_terminate_cond, results)) # Call the NLP post-solve callback config.call_after_subproblem_solve(nlp_model, solve_data) # if feasible, call the NLP post-feasible callback if nlp_result.feasible: config.call_after_subproblem_feasible(nlp_model, solve_data) return nlp_result
def solve_NLP(nlp_model, solve_data, config): """Solve the NLP subproblem.""" config.logger.info('Solving nonlinear subproblem for ' 'fixed binaries and logical realizations.') # Error checking for unfixed discrete variables unfixed_discrete_vars = detect_unfixed_discrete_vars(nlp_model) assert len(unfixed_discrete_vars) == 0, \ "Unfixed discrete variables exist on the NLP subproblem: {0}".format( list(v.name for v in unfixed_discrete_vars)) GDPopt = nlp_model.GDPopt_utils if config.subproblem_presolve: preprocess_subproblem(nlp_model, config) initialize_subproblem(nlp_model, solve_data) # Callback immediately before solving NLP subproblem config.call_before_subproblem_solve(nlp_model, solve_data) nlp_solver = SolverFactory(config.nlp_solver) if not nlp_solver.available(): raise RuntimeError("NLP solver %s is not available." % config.nlp_solver) with SuppressInfeasibleWarning(): results = nlp_solver.solve(nlp_model, **config.nlp_solver_args) nlp_result = SubproblemResult() nlp_result.feasible = True nlp_result.var_values = list(v.value for v in GDPopt.variable_list) nlp_result.pyomo_results = results nlp_result.dual_values = list( nlp_model.dual.get(c, None) for c in GDPopt.constraint_list) subprob_terminate_cond = results.solver.termination_condition if (subprob_terminate_cond is tc.optimal or subprob_terminate_cond is tc.locallyOptimal or subprob_terminate_cond is tc.feasible): pass elif subprob_terminate_cond is tc.infeasible: config.logger.info('NLP subproblem was infeasible.') nlp_result.feasible = False elif subprob_terminate_cond is tc.maxIterations: # TODO try something else? Reinitialize with different initial # value? config.logger.info( 'NLP subproblem failed to converge within iteration limit.') if is_feasible(nlp_model, config): config.logger.info( 'NLP solution is still feasible. ' 'Using potentially suboptimal feasible solution.') else: nlp_result.feasible = False elif subprob_terminate_cond is tc.internalSolverError: # Possible that IPOPT had a restoration failure config.logger.info("NLP solver had an internal failure: %s" % results.solver.message) nlp_result.feasible = False else: raise ValueError('GDPopt unable to handle NLP subproblem termination ' 'condition of %s. Results: %s' % (subprob_terminate_cond, results)) # Call the NLP post-solve callback config.call_after_subproblem_solve(nlp_model, solve_data) # if feasible, call the NLP post-feasible callback if nlp_result.feasible: config.call_after_subproblem_feasible(nlp_model, solve_data) return nlp_result
def solve_NLP(nlp_model, solve_data, config): """Solve the NLP subproblem.""" config.logger.info( 'Solving nonlinear subproblem for ' 'fixed binaries and logical realizations.') # Error checking for unfixed discrete variables unfixed_discrete_vars = detect_unfixed_discrete_vars(nlp_model) assert len(unfixed_discrete_vars) == 0, \ "Unfixed discrete variables exist on the NLP subproblem: {0}".format( list(v.name for v in unfixed_discrete_vars)) GDPopt = nlp_model.GDPopt_utils if config.subproblem_presolve: preprocess_subproblem(nlp_model, config) initialize_subproblem(nlp_model, solve_data) # Callback immediately before solving NLP subproblem config.call_before_subproblem_solve(nlp_model, solve_data) nlp_solver = SolverFactory(config.nlp_solver) if not nlp_solver.available(): raise RuntimeError("NLP solver %s is not available." % config.nlp_solver) with SuppressInfeasibleWarning(): results = nlp_solver.solve(nlp_model, **config.nlp_solver_args) nlp_result = SubproblemResult() nlp_result.feasible = True nlp_result.var_values = list(v.value for v in GDPopt.variable_list) nlp_result.pyomo_results = results nlp_result.dual_values = list( nlp_model.dual.get(c, None) for c in GDPopt.constraint_list) subprob_terminate_cond = results.solver.termination_condition if (subprob_terminate_cond is tc.optimal or subprob_terminate_cond is tc.locallyOptimal or subprob_terminate_cond is tc.feasible): pass elif subprob_terminate_cond is tc.infeasible: config.logger.info('NLP subproblem was infeasible.') nlp_result.feasible = False elif subprob_terminate_cond is tc.maxIterations: # TODO try something else? Reinitialize with different initial # value? config.logger.info( 'NLP subproblem failed to converge within iteration limit.') if is_feasible(nlp_model, config): config.logger.info( 'NLP solution is still feasible. ' 'Using potentially suboptimal feasible solution.') else: nlp_result.feasible = False elif subprob_terminate_cond is tc.internalSolverError: # Possible that IPOPT had a restoration failure config.logger.info( "NLP solver had an internal failure: %s" % results.solver.message) nlp_result.feasible = False else: raise ValueError( 'GDPopt unable to handle NLP subproblem termination ' 'condition of %s. Results: %s' % (subprob_terminate_cond, results)) # Call the NLP post-solve callback config.call_after_subproblem_solve(nlp_model, solve_data) # if feasible, call the NLP post-feasible callback if nlp_result.feasible: config.call_after_subproblem_feasible(nlp_model, solve_data) return nlp_result
def solve_MINLP(model, solve_data, config): """Solve the MINLP subproblem.""" config.logger.info( "Solving MINLP subproblem for fixed logical realizations." ) GDPopt = model.GDPopt_utils if config.subproblem_presolve: preprocess_subproblem(model, config) initialize_subproblem(model, solve_data) # Callback immediately before solving NLP subproblem config.call_before_subproblem_solve(model, solve_data) minlp_solver = SolverFactory(config.minlp_solver) if not minlp_solver.available(): raise RuntimeError("MINLP solver %s is not available." % config.minlp_solver) with SuppressInfeasibleWarning(): results = minlp_solver.solve(model, **config.minlp_solver_args) subprob_result = SubproblemResult() subprob_result.feasible = True subprob_result.var_values = list(v.value for v in GDPopt.variable_list) subprob_result.pyomo_results = results subprob_result.dual_values = list( model.dual.get(c, None) for c in GDPopt.constraint_list) subprob_terminate_cond = results.solver.termination_condition if (subprob_terminate_cond is tc.optimal or subprob_terminate_cond is tc.locallyOptimal or subprob_terminate_cond is tc.feasible): pass elif subprob_terminate_cond is tc.infeasible: config.logger.info('MINLP subproblem was infeasible.') subprob_result.feasible = False elif subprob_terminate_cond is tc.maxIterations: # TODO try something else? Reinitialize with different initial # value? config.logger.info( 'MINLP subproblem failed to converge within iteration limit.') if is_feasible(model, config): config.logger.info( 'MINLP solution is still feasible. ' 'Using potentially suboptimal feasible solution.') else: subprob_result.feasible = False elif subprob_terminate_cond is tc.intermediateNonInteger: config.logger.info( "MINLP solver could not find feasible integer solution: %s" % results.solver.message) subprob_result.feasible = False else: raise ValueError( 'GDPopt unable to handle MINLP subproblem termination ' 'condition of %s. Results: %s' % (subprob_terminate_cond, results)) # Call the subproblem post-solve callback config.call_after_subproblem_solve(model, solve_data) # if feasible, call the subproblem post-feasible callback if subprob_result.feasible: config.call_after_subproblem_feasible(model, solve_data) return subprob_result