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from __future__ import print_function 

from __future__ import division 

from builtins import range 

import numpy as np 

from gpkit.small_scripts import mag 

from gpkit.exceptions import InvalidGPConstraint 

from gpkit.small_scripts import mag 

from gpkit import Model, Variable, Monomial 

 

from robust.robust import RobustModel 

from robust.robust_gp_tools import RobustGPTools 

from robust.simulations.read_simulation_data import objective_proboffailure_vs_gamma 

 

import matplotlib.pyplot as plt 

import multiprocessing as mp 

import scipy.stats as stats 

 

# For the following simulation functions, we define common inputs as the following: 

# :model: GP or SP model of interest 

# :model_name: string for printing 

# :gamma: array of floats to specify set size 

# :number_of_iterations: # of MC samples 

# :numbers_of_linear_sections: array of integer sections 

# :linearization_tolerance: max error of pwl approx 

# :verbosity: 0-4 for printout 

# :file_name: directory for printing 

# :number_of_time_average_solves: # of solves for solution time analysis 

# :methods: type of conservative approximation used, dict 

# :uncertainty_sets: string defining type of set 

# :nominal_solution: solution of model with zero uncertainty 

# :nominal_solve_time: solve time of model with zero uncertainty 

# :nominal_number_of_constraints: 

# :directly_uncertain_vars_subs: dict of uncertain parameter MC samples 

# :return: 

 

def pickleable_robust_solve_time(robust_model, verbosity, min_num_of_linear_sections, 

max_num_of_linear_sections, linearization_tolerance): 

""" 

Wrapper for robustsolve for parallelism. 

""" 

robust_model_solution = robust_model.robustsolve(verbosity=verbosity, 

minNumOfLinearSections=min_num_of_linear_sections, 

maxNumOfLinearSections=max_num_of_linear_sections, 

linearizationTolerance=linearization_tolerance) 

return robust_model_solution['soltime'] 

 

def get_avg_robust_solve_time(number_of_time_average_solves, robust_model, verbosity, min_num_of_linear_sections, 

max_num_of_linear_sections, linearization_tolerance, parallel=False): 

""" 

Given a number of solves, gives the average solution time of a robust model. Parallel option. 

""" 

if parallel: 

pool = mp.Pool(mp.cpu_count()-1) 

processes = [] 

timesolutions = [] 

for i in range(number_of_time_average_solves): 

p = pool.apply_async(pickleable_robust_solve_time, args=(robust_model, verbosity, min_num_of_linear_sections, 

max_num_of_linear_sections,linearization_tolerance), callback=timesolutions.append) 

processes.append(p) 

pool.close() 

pool.join() 

else: 

solutions = [robust_model.robustsolve(verbosity=verbosity) 

for i in range(number_of_time_average_solves)] 

timesolutions = [s['soltime'] for s in solutions] 

return np.mean(timesolutions) 

 

def simulate_robust_model(model, method, uncertainty_set, gamma, directly_uncertain_vars_subs, 

number_of_iterations, linearization_tolerance, min_num_of_linear_sections, 

max_num_of_linear_sections, verbosity, nominal_solution, 

number_of_time_average_solves, parallel=False): 

""" 

Simulates a robust model given uncertain outcomes. 

""" 

print( 

method[ 

'name'] + ' under ' + uncertainty_set + ' uncertainty set: \n' + '\t' + 'gamma = %s\n' % gamma 

+ '\t' + 'minimum number of piecewise-linear sections = %s\n' % min_num_of_linear_sections 

+ '\t' + 'maximum number of piecewise-linear sections = %s\n' % max_num_of_linear_sections) 

 

robust_model = RobustModel(model, uncertainty_set, gamma=gamma, twoTerm=method['twoTerm'], 

boyd=method['boyd'], simpleModel=method['simpleModel'], 

nominalsolve=nominal_solution) 

 

robust_model_solution = robust_model.robustsolve(verbosity=verbosity, 

minNumOfLinearSections=min_num_of_linear_sections, 

maxNumOfLinearSections=max_num_of_linear_sections, 

linearizationTolerance=linearization_tolerance) 

 

robust_model_solve_time = get_avg_robust_solve_time(number_of_time_average_solves, 

robust_model, verbosity, min_num_of_linear_sections, 

max_num_of_linear_sections, 

linearization_tolerance, parallel) 

 

simulation_results = RobustGPTools.probability_of_failure(model, robust_model_solution, 

directly_uncertain_vars_subs, 

number_of_iterations, 

verbosity=0, parallel=parallel) 

 

return robust_model, robust_model_solution, robust_model_solve_time, simulation_results 

 

 

def print_simulation_results(robust_model, robust_model_solution, robust_model_solve_time, 

nominal_model_solve_time, nominal_no_of_constraints, nominal_cost, 

simulation_results, file_id): 

file_id.write('\t\t\t' + 'Probability of failure: %s\n' % simulation_results[0]) 

file_id.write('\t\t\t' + 'Average performance: %s\n' % mag(simulation_results[1])) 

file_id.write('\t\t\t' + 'Relative average performance: %s\n' % 

(mag(simulation_results[1]) / float(mag(nominal_cost)))) 

file_id.write('\t\t\t' + 'Worst-case performance: %s\n' % mag(robust_model_solution['cost'])) 

file_id.write('\t\t\t' + 'Relative worst-case performance: %s\n' % 

(mag(robust_model_solution['cost']) / float(mag(nominal_cost)))) 

try: 

number_of_constraints = \ 

len([cnstrnt for cnstrnt in robust_model.get_robust_model().flat(constraintsets=False)]) 

except AttributeError: 

number_of_constraints = \ 

len([cnstrnt for cnstrnt in robust_model.get_robust_model()[-1].flat(constraintsets=False)]) 

file_id.write('\t\t\t' + 'Number of constraints: %s\n' % number_of_constraints) 

file_id.write('\t\t\t' + 'Relative number of constraints: %s\n' % 

(number_of_constraints / float(nominal_no_of_constraints))) 

file_id.write('\t\t\t' + 'Setup time: %s\n' % robust_model_solution['setuptime']) 

file_id.write('\t\t\t' + 'Relative setup time: %s\n' % 

(robust_model_solution['setuptime'] / float(nominal_model_solve_time))) 

file_id.write('\t\t\t' + 'Solve time: %s\n' % robust_model_solve_time) 

file_id.write('\t\t\t' + 'Relative solve time: %s\n' % 

(robust_model_solve_time / float(nominal_model_solve_time))) 

file_id.write('\t\t\t' + 'Number of linear sections: %s\n' % robust_model_solution['numoflinearsections']) 

file_id.write( 

'\t\t\t' + 'Upper lower relative error: %s\n' % mag(robust_model_solution['upperLowerRelError'])) 

 

 

def print_variable_gamma_results(model, model_name, gammas, number_of_iterations, 

min_num_of_linear_sections, max_num_of_linear_sections, verbosity, 

linearization_tolerance, file_name, number_of_time_average_solves, 

methods, uncertainty_sets, nominal_solution, nominal_solve_time, 

nominal_number_of_constraints, directly_uncertain_vars_subs): 

 

f = open(file_name, 'w') 

f.write(model_name + ' Results: variable gamma\n') 

f.write('----------------------------------------------------------\n') 

cost_label = model.cost.str_without() 

split_label = cost_label.split(' ') 

capitalized_cost_label = '' 

for word in split_label: 

capitalized_cost_label += word.capitalize() + ' ' 

f.write('Objective: %s\n' % capitalized_cost_label) 

f.write('Units: %s\n' % model.cost.units) 

f.write('----------------------------------------------------------\n') 

f.write('Number of iterations: %s\n' % number_of_iterations) 

f.write('Minimum number of piecewise-linear sections: %s\n' % min_num_of_linear_sections) 

f.write('Maximum number of piecewise-linear sections: %s\n' % max_num_of_linear_sections) 

f.write('Linearization tolerance: %s\n' % linearization_tolerance) 

f.write('----------------------------------------------------------\n') 

f.write('Nominal cost: %s\n' % nominal_solution['cost']) 

f.write('Average nominal solve time: %s\n' % nominal_solve_time) 

f.write('Nominal number of constraints: %s\n' % nominal_number_of_constraints) 

f.write('----------------------------------------------------------\n') 

 

for gamma in gammas: 

f.write('Gamma = %s:\n' % gamma) 

for method in methods: 

f.write('\t' + method['name'] + ':\n') 

for uncertainty_set in uncertainty_sets: 

f.write('\t\t' + uncertainty_set + ':\n') 

robust_model, robust_model_solution, robust_model_solve_time, simulation_results = \ 

simulate_robust_model(model, method, uncertainty_set, gamma, directly_uncertain_vars_subs, 

number_of_iterations, linearization_tolerance, 

min_num_of_linear_sections, 

max_num_of_linear_sections, verbosity, nominal_solution, 

number_of_time_average_solves) 

print_simulation_results(robust_model, robust_model_solution, robust_model_solve_time, 

nominal_solve_time, nominal_number_of_constraints, nominal_solution['cost'], 

simulation_results, f) 

f.close() 

 

def variable_gamma_results(model, methods, gammas, number_of_iterations, 

min_num_of_linear_sections, max_num_of_linear_sections, verbosity, 

linearization_tolerance, number_of_time_average_solves, 

uncertainty_sets, nominal_solution, directly_uncertain_vars_subs, parallel=False): 

""" 

Simulates a GP or SP model for a range of gammas, i.e. uncertainty set size. 

Outputs are dicts that have the key format: [deltaValue (float), methodName (string), uncertaintySet (string)] 

""" 

solutions = {} 

solve_times = {} 

simulations = {} 

number_of_constraints = {} 

for gamma in gammas: 

for method in methods: 

for uncertainty_set in uncertainty_sets: 

ind = (gamma, method['name'], uncertainty_set) 

robust_model, robust_model_solution, robust_model_solve_time, simulation_results = \ 

simulate_robust_model(model, method, uncertainty_set, gamma, directly_uncertain_vars_subs, 

number_of_iterations, linearization_tolerance, 

min_num_of_linear_sections, 

max_num_of_linear_sections, verbosity, nominal_solution, 

number_of_time_average_solves, parallel) 

try: 

nconstraints = \ 

len([cnstrnt for cnstrnt in robust_model.get_robust_model().flat(constraintsets=False)]) 

except AttributeError: 

nconstraints = \ 

len([cnstrnt for cnstrnt in robust_model.get_robust_model()[-1].flat(constraintsets=False)]) 

solutions[ind] = robust_model_solution 

solve_times[ind] = robust_model_solve_time 

simulations[ind] = simulation_results 

number_of_constraints[ind] = nconstraints 

return solutions, solve_times, simulations, number_of_constraints 

 

def variable_goal_results(model, methods, deltas, number_of_iterations, 

min_num_of_linear_sections, max_num_of_linear_sections, verbosity, 

linearization_tolerance, number_of_time_average_solves, 

uncertainty_sets, nominal_solution, directly_uncertain_vars_subs, parallel=False): 

""" 

Simulates a GP or SP model for a range of deltas in the goal programming form. 

i.e. maximizes uncertainty set size given an acceptable penalty delta on the objective. 

Outputs are dicts that have the key format: [deltaValue (float), methodName (string), uncertaintySet (string)] 

""" 

solutions = {} 

solve_times = {} 

simulations = {} 

number_of_constraints = {} 

Gamma = Variable('\\Gamma', '-', 'Uncertainty bound') 

solBound = Variable('1+\\delta', '-', 'Acceptable optimal solution bound', fix = True) 

origcost = model.cost 

mGoal = Model(1 / Gamma, [model, origcost <= Monomial(nominal_solution(origcost)) * solBound, Gamma <= 1e30, solBound <= 1e30], 

model.substitutions) 

for delta in deltas: 

mGoal.substitutions.update({'1+\\delta': 1 + delta}) 

for method in methods: 

for uncertainty_set in uncertainty_sets: 

robust_goal_model = RobustModel(mGoal, uncertainty_set, gamma=Gamma, twoTerm=method['twoTerm'], 

boyd=method['boyd'], simpleModel=method['simpleModel']) 

 

robust_model_solution = robust_goal_model.robustsolve(verbosity=verbosity, 

minNumOfLinearSections=min_num_of_linear_sections, 

maxNumOfLinearSections=max_num_of_linear_sections, 

linearizationTolerance=linearization_tolerance) 

 

robust_model_solve_time = get_avg_robust_solve_time(number_of_time_average_solves, 

robust_goal_model, verbosity, min_num_of_linear_sections, 

max_num_of_linear_sections, 

linearization_tolerance, parallel) 

 

simulation_results = RobustGPTools.probability_of_failure(model, robust_model_solution, 

directly_uncertain_vars_subs, 

number_of_iterations, 

verbosity=0, parallel=parallel) 

try: 

nconstraints = \ 

len([cnstrnt for cnstrnt in robust_goal_model.get_robust_model().flat(constraintsets=False)]) 

except AttributeError: 

nconstraints = \ 

len([cnstrnt for cnstrnt in robust_goal_model.get_robust_model()[-1].flat(constraintsets=False)]) 

ind = (delta, method['name'], uncertainty_set) 

solutions[ind] = robust_model_solution 

solve_times[ind] = robust_model_solve_time 

simulations[ind] = simulation_results 

number_of_constraints[ind] = nconstraints 

return solutions, solve_times, simulations, number_of_constraints 

 

def filter_gamma_result_dict(dict, tupInd1, tupVal1, tupInd2, tupVal2): 

""" 

Filters the items in outputs of variable_gamma_results or variable_goal_results 

with 2 out of 3 keys. 

""" 

filteredResult = {} 

for i in sorted(dict.keys()): 

if i[tupInd1] == tupVal1 and i[tupInd2] == tupVal2: 

filteredResult[i] = dict[i] 

return filteredResult 

 

def plot_gamma_result_PoFandCost(title, objective_name, objective_units, filteredResult, filteredSimulations, stddev = True): 

gammas = [] 

objective_costs = [] 

pofs = [] 

objective_stddev = [] 

for i in sorted(filteredResult.keys()): 

gammas.append(i[0]) 

objective_stddev.append(filteredSimulations[i][2]) 

objective_costs.append(filteredSimulations[i][1]) 

pofs.append(filteredSimulations[i][0]) 

if not stddev: 

objective_stddev = None 

objective_proboffailure_vs_gamma(gammas, objective_costs, objective_name, objective_units, 

np.min(objective_costs), np.max(objective_costs), pofs, title, objective_stddev) 

 

def plot_goal_result_PoFandCost(title, objective_name, objective_varkey, objective_units, filteredResult, filteredSimulations): 

gammas = [] 

objective_costs = [] 

pofs = [] 

objective_stddev = [] 

for i in sorted(filteredResult.keys()): 

gammas.append(filteredResult[i]("\\Gamma").magnitude) 

objective_stddev.append(filteredSimulations[i][2]) 

objective_costs.append(mag(filteredResult[i](objective_varkey))) 

pofs.append(filteredSimulations[i][0]) 

objective_proboffailure_vs_gamma(gammas, objective_costs, objective_name, objective_units, 

np.min(objective_costs), np.max(objective_costs), pofs, title, None) 

 

def print_variable_pwlsections_results(model, model_name, gamma, number_of_iterations, 

numbers_of_linear_sections, linearization_tolerance, 

verbosity, file_name, number_of_time_average_solves, 

methods, uncertainty_sets, nominal_solution, nominal_solve_time, 

nominal_number_of_constraints, directly_uncertain_vars_subs): 

""" 

Simulates a model for different numbers of PWL sections for each posy. 

""" 

 

f = open(file_name, 'w') 

f.write(model_name + ' Results: variable piecewise-linear sections\n') 

f.write('----------------------------------------------------------\n') 

cost_label = model.cost.str_without() 

split_label = cost_label.split(' ') 

capitalized_cost_label = '' 

for word in split_label: 

capitalized_cost_label += word.capitalize() + ' ' 

f.write('Objective: %s\n' % capitalized_cost_label) 

f.write('Units: %s\n' % model.cost.units) 

f.write('----------------------------------------------------------\n') 

f.write('Number of iterations: %s\n' % number_of_iterations) 

f.write('gamma: %s\n' % gamma) 

f.write('Linearization tolerance: %s\n' % linearization_tolerance) 

f.write('----------------------------------------------------------\n') 

f.write('Nominal cost: %s\n' % nominal_solution['cost']) 

f.write('Average nominal solve time: %s\n' % nominal_solve_time) 

f.write('Nominal number of constraints: %s\n' % nominal_number_of_constraints) 

f.write('----------------------------------------------------------\n') 

 

for number_of_linear_sections in numbers_of_linear_sections: 

f.write('number of piecewise-linear sections = %s:\n' % number_of_linear_sections) 

for method in methods: 

f.write('\t' + method['name'] + ':\n') 

for uncertainty_set in uncertainty_sets: 

f.write('\t\t' + uncertainty_set + ':\n') 

robust_model, robust_model_solution, robust_model_solve_time, simulation_results = \ 

simulate_robust_model(model, method, uncertainty_set, gamma, directly_uncertain_vars_subs, 

number_of_iterations, linearization_tolerance, 

number_of_linear_sections, 

number_of_linear_sections, verbosity, nominal_solution, 

number_of_time_average_solves) 

print_simulation_results(robust_model, robust_model_solution, robust_model_solve_time, 

nominal_solve_time, nominal_number_of_constraints, nominal_solution['cost'], 

simulation_results, f) 

f.close() 

 

 

def generate_model_properties(model, number_of_time_average_solves, number_of_iterations, distribution = None): 

""" 

Solves the nominal model, and generates MC samples 

:param model: GP or SP model of interest, with uncertainties 

:param number_of_time_average_solves: # of solves for solution time analysis 

:param number_of_iterations: # of MC samples for simulation 

:param distribution: distribution for MC samples, 'normal' or 'uniform otherwise 

:return: nominal solution, nominal solve time, nominal number of constraints, and MC samples of uncertain inputs 

""" 

try: 

nominal_solution = model.solve(verbosity=0) 

nominal_solve_time = nominal_solution['soltime'] 

for i in range(number_of_time_average_solves-1): 

nominal_solve_time += model.solve(verbosity=0)['soltime'] 

except InvalidGPConstraint: 

nominal_solution = model.localsolve(verbosity=0) 

nominal_solve_time = nominal_solution['soltime'] 

for i in range(number_of_time_average_solves-1): 

nominal_solve_time += model.localsolve(verbosity=0)['soltime'] 

nominal_solve_time = nominal_solve_time / number_of_time_average_solves 

 

if distribution == 'normal' or 'Gaussian': 

directly_uncertain_vars_subs = [{k: stats.truncnorm.rvs(-3. , 3. , loc=v, scale=(v*k.key.pr/300.)) 

for k, v in list(model.substitutions.items()) 

if k in model.varkeys and RobustGPTools.is_directly_uncertain(k)} 

for _ in range(number_of_iterations)] 

else: 

directly_uncertain_vars_subs = [{k: np.random.uniform(v - k.key.pr * v / 100.0, v + k.key.pr * v / 100.0) 

for k, v in list(model.substitutions.items()) 

if k in model.varkeys and RobustGPTools.is_directly_uncertain(k)} 

for _ in range(number_of_iterations)] 

nominal_number_of_constraints = len([cs for cs in model.flat(constraintsets=False)]) 

 

return nominal_solution, nominal_solve_time, nominal_number_of_constraints, directly_uncertain_vars_subs 

 

if __name__ == '__main__': 

pass