def solve_model(self, max_iter, max_time, relaxation):
if relaxation:
model = self.model_lp
else:
model = self.model_ip
# solving the model
if relaxation:
self.model_lp_solved = SDDP(self.model_lp)
self.model_lp_solved.solve(
n_processes=1,
max_iterations=max_iter,
max_stable_iterations=
20, # The maximum number of iterations to have the same deterministic bound
max_time=max_time, # hours*minutes*seconds (in seconds)
)
self.data.dat['OBJ_BOUND'] = self.model_lp_solved.db[-1]
elif not relaxation:
self.model_ip_solved = SDDiP(self.model_ip)
self.model_ip_solved.solve(
n_processes=1,
n_steps=1,
max_iterations=max_iter,
max_stable_iterations=
11, # The maximum number of iterations to have the same deterministic bound
max_time=max_time, # hours*minutes*seconds (in seconds)
n_simulations=5000, #500, -1 calculates the epv
#freq_evaluations=5, tol = 1e-3, #optimality gap
tol_diff=1e-4,
freq_comparisons=self.
freq_comp, #Turn to 1 the obtain confidence interval on policy value
query_policy_value=
False, # turn this on to get ALL the output for the graph (CI)
cuts=self.cuts, #['LG','B','SB']
)
self.data.evaluation[
'first_stage_solution'] = self.model_ip_solved.first_stage_solution
self.data.evaluation['bounds'] = self.model_ip_solved.bounds
self.data.evaluation['pv'] = self.model_ip_solved.pv
self.data.evaluation['db'] = self.model_ip_solved.db
self.data.evaluation[
'total_time'] = self.model_ip_solved.total_time
self.data.evaluation['iteration'] = self.model_ip_solved.iteration
self.get_first_stage_solution()
for key, value in self.model_ip_solved.first_stage_solution.items(
):
if value > 0.99 and value < 1.01:
print(key)
def test_continuous(self):
self.nvici = construct_nvici()
self.nvici.discretize(n_samples=10)
SDDiP(self.nvici).solve(
cuts=['B'],
max_iterations=10,
)
def test_LG_bin_cut(self):
self.initialize()
self.nvidi.binarize()
SDDiP(self.nvidi).solve(
cuts=['LG'],
max_iterations=10,
)
def test_LG_cut(self):
self.initialize()
SDDiP(self.nvidi).solve(
cuts=['B', 'LG'],
pattern={'cycle': [1, 2]},
max_iterations=10,
)
def test_SB_cut(self):
self.initialize()
SDDiP(self.nvidi).solve(
cuts=['B', 'SB'],
pattern={'in': [0, 3]},
max_iterations=10,
)
m.addConstrs(hydro[i] >= z[i] * hydro_['UB'][:4][i] / 2
for i in range(4))
m.addConstrs(thermal_sum[i] >= (1 - z[i]) * thermal_mid_level[i]
for i in range(4))
HydroThermal.discretize(n_samples=100, random_state=seed)
if solver == 'Extensive':
HT_extensive = Extensive(HydroThermal)
HT_extensive.solve(outputFlag=0, TimeLimit=time_limit)
print('lower bound', HT_extensive.objBound)
print('upper bound', HT_extensive.objVal)
print('total time', HT_extensive.total_time)
print('gap', HT_extensive.MIPGap)
if solver == 'SDDiP':
HydroThermal.binarize(bin_stage=T)
HT_sddp = SDDiP(HydroThermal)
HT_sddp.solve(
logFile=0,
logToConsole=0,
cuts=[cut],
n_processes=1,
n_steps=1,
max_iterations=n_iterations,
)
result = Evaluation(HydroThermal)
if T in [2, 3]:
result.run(random_state=666, n_simulations=-1)
else:
result.run(random_state=666, n_simulations=3000)
resultTrue = EvaluationTrue(HydroThermal)
resultTrue.run(random_state=666, n_simulations=3000)
true = demand_sampler(numpy.random.RandomState(0), 1000)
fig_mca, ax_mca = plt.subplots(6,
2,
figsize=(10, 10),
sharey='row',
sharex=True)
fig_mca.text(0.5, 0.01, 'stage', ha='center')
fig_mca.text(0, 0.5, 'demand', va='center', rotation='vertical')
for j_idx, j in enumerate(J):
fig_mca = fan_plot(true[:, :, j_idx], ax=ax_mca[j_idx][0])
fig_mca = fan_plot(simulation[:, :, j_idx], ax=ax_mca[j_idx][1])
fig_mca.tight_layout()
fig_mca.savefig("./result/airline_MCA.png", dpi=1200)
fig_bound, ax_bound = plt.subplots(2, 1, figsize=(10, 5), sharey=True)
for cut_index, cut in enumerate(['B', 'SB']):
airline_sddp = SDDiP(airline)
airline_sddp.solve(cuts=[cut],
n_processes=1,
n_steps=1,
max_iterations=100)
result = Evaluation(airline)
result.run(random_state=666, n_simulations=3000)
resultTrue = EvaluationTrue(airline)
resultTrue.run(random_state=666, n_simulations=3000)
summary['model'].append(idx)
summary['cut'].append(cut)
summary['time'].append(airline_sddp.total_time)
summary['gap'].append(result.gap)
summary['bound'].append(result.db)
summary['CI_approx_lower'].append(result.CI[0])
summary['CI_approx_upper'].append(result.CI[1])
def test_B_cut(self):
self.initialize()
SDDiP(self.nvidi).solve(
cuts=['B'],
max_iterations=10,
)
import numpy
import gurobipy
numpy.random.seed(2)
T = 5
numSeats = 5
numScen = 5
offer = numpy.random.randint(numSeats, size=(T, numScen, numSeats))
price = [[3 + t for _ in range(20)] for t in range(T)]
selling = MSIP(T=T, sense=-1, bound=100)
for t in range(T):
m = selling.models[t]
now, past = m.addStateVars(numSeats, vtype='B', name="seatCondition")
if t == 0:
m.addConstrs(past[i] == 1 for i in range(numSeats))
else:
accept_offer = m.addVars(numSeats,
vtype='B',
obj=price[t],
name="acceptOffer")
m.addConstrs(
(accept_offer[i] <= 0 for i in range(numSeats)),
uncertainty=offer[t],
)
m.addConstrs(now[i] == past[i] - accept_offer[i]
for i in range(numSeats))
SDDiP(selling).solve(max_iterations=20, cuts=['LG'])
resultTrue = EvaluationTrue(selling)
resultTrue.run(n_simulations=100)
"""
from msppy.msp import MSIP
from msppy.solver import Extensive, SDDiP
import numpy
numpy.random.seed(3)
T = 4
precision = 1
rhs = [numpy.random.normal(-1,1,size=10) for _ in range(T-1)]
absolute = MSIP(T=T, bound=0)
for t in range(T):
m = absolute[t]
x_now, x_past = m.addStateVar(lb=-100, ub=100, name='x')
if t == 0:
m.addConstr(x_now == 0)
else:
y = m.addVar(name='y', obj=1)
c = m.addVar(vtype='B', name='c')
slack = m.addVar(ub=1/10**(precision), name='slack')
m.addConstr(y >= -x_now)
m.addConstr(y >= x_now)
m.addConstr(
x_now - x_past - 2*c + slack == -1,
uncertainty={'rhs': rhs[t-1]}
)
absolute.binarize(bin_stage=T, precision=precision)
Extensive(absolute).solve(outputFlag=0)
absolute_sddip = SDDiP(absolute)
absolute_sddip.solve(cuts=['LG'], n_steps=3, n_processes=3, max_iterations=30)
#absolute.extensive(outputflag=0)
class decifit:
def __init__(self, instance):
self.instance = instance
self.data = Data(instance)
self.Evaluation = None
self.precision = 2
self.max_iter = 10
self.num_samples = 6
self.n_markov_states = 10
self.sample_seed = 5
self.markov = True
self.two_factor = False
self.percentile = False
self.percentile_level = 50
self.extensive = False
self.freq_comp = 3
self.cuts = ['LG', 'B', 'SB']
self.print_decision_matrix = False
def sample_path_generator(self, random_state, size):
output = np.empty([size, self.data.dat['num_stages'],
4]) #T:time horizon
output[:, 0, 0] = self.data.dat['xi_0'] #equilibrium factor
output[:, 0, 1] = self.data.dat['chi_0'] #deviation factor
output[:, 0, 2] = np.exp(output[:, 0, 0] + output[:, 0, 1]) #prices
output[:, 0, 3] = output[:, 0, 2] # discounted prices
for t in range(1, self.data.dat['num_stages']):
standard_normal_values = random_state.multivariate_normal(
mean=[0, 0],
cov=[[
self.data.dat['var_std_normal'],
self.data.dat['covariance']
],
[
self.data.dat['covariance'],
self.data.dat['var_std_normal']
]],
size=size)
output[:,t,0] = self.data.dat['alpha_xi'][self.data.dat['num_years_per_stage'][t]-1] + \
output[:,t-1,0] + \
standard_normal_values[:,0]*self.data.dat['eps_xi_par'][self.data.dat['num_years_per_stage'][t]-1]
output[:,t,1] = self.data.dat['alpha_chi'][self.data.dat['num_years_per_stage'][t]-1] + \
output[:,t-1,1]*self.data.dat['beta_chi'][self.data.dat['num_years_per_stage'][t]-1] + \
standard_normal_values[:,1]*self.data.dat['eps_chi_par'][self.data.dat['num_years_per_stage'][t]-1]
output[:, t,
2] = np.minimum(np.exp(output[:, t, 0] + output[:, t, 1]),
np.repeat(self.data.dat['P_UPPER_BOUND'],
size)) #PRICE
output[:, t,
3] = output[:, t, 2] * self.data.dat['discount_factor'][
t] #DISCOUNTED PRICE
return output
def construct_model(self, precision, num_samples, n_markov_states,
markov_method, relaxation):
self.n_markov_states = n_markov_states
self.num_samples = num_samples
if self.two_factor: # for the time series approach
self.data.dat['query'].append('dev_fact')
self.data.dat['query'].append('eq_fact')
self.read_plf(
os.path.join(os.getcwd(), r'decifit/utils/plf_data.csv'))
else:
self.data.dat['prices'] = self.sample_path_generator(
random_state=np.random.RandomState(6), size=1000)
if relaxation: #this constructs the lp relaxation of the problem
self.model_lp = MSLP(T=self.data.dat['num_stages'], sense=-1)
model = self.model_lp
elif not relaxation: #constructs the integer version
self.model_ip = MSIP(
T=self.data.dat['num_stages'], sense=-1
) #, bound=self.data.dat['OBJ_BOUND'], should be a uniform bound on the optimum in each stage optimization problem
model = self.model_ip
# sense=-1: maximization problem, sense = 1: minimization, discount = 0.995
if self.markov:
model.add_Markovian_uncertainty(self.sample_path_generator)
for t in range(self.data.dat['num_stages']):
m = model.models[t]
# ----------------------------------- #
# VARIABLES
# ----------------------------------- #
# STATE VARIABLES:
if not relaxation:
variable_type = 'B'
elif relaxation:
variable_type = gurobipy.GRB.CONTINUOUS
x_activities_now, x_activities_past = m.addStateVars(
[(tt, a) for a in self.data.dat['A_ACTIVITIES']
for tt in range(
0, self.data.dat['last_stage_to_start_activity'][a])],
name='x_act',
lb=0,
ub=1,
vtype=variable_type)
y_shutdown_now, y_shutdown_past = m.addStateVar(
name='y_sd', lb=0, ub=1, vtype=variable_type)
#For the Time Series approach, the factors also become state variables
if not self.markov and not self.percentile: # TS APPROACH
equilibrium_factor_now, equilibrium_factor_past = m.addStateVar(
lb=self.data.dat['lower_bound_eq_factor'],
ub=self.data.dat['upper_bound_eq_factor'],
name='eq_fact',
vtype=gurobipy.GRB.CONTINUOUS) #xi
deviation_factor_now, deviation_factor_past = m.addStateVar(
lb=self.data.dat['lower_bound_dev_factor'],
ub=self.data.dat['upper_bound_dev_factor'],
name='dev_fact',
vtype=gurobipy.GRB.CONTINUOUS) #chi
# CONTROL VARIABLES:
if not self.two_factor:
cost = m.addVar(vtype=gurobipy.GRB.CONTINUOUS,
name='cost',
lb=0,
ub=self.data.dat['MAX_COST'],
obj=-self.data.dat['discount_factor'][t])
if self.markov:
if self.n_markov_states == 1:
q_total_production = m.addVar(
lb=self.data.dat['Q_MIN'],
ub=self.data.dat['Q_MAX'],
vtype=gurobipy.GRB.CONTINUOUS,
name='q_total_production',
obj=numpy.percentile(
self.data.dat['prices'][:, t, 2],
self.percentile_level) *
self.data.dat['discount_factor'][t])
else:
q_total_production = m.addVar(
lb=self.data.dat['Q_MIN'],
ub=self.data.dat['Q_MAX'],
vtype=gurobipy.GRB.CONTINUOUS,
name='q_total_production',
uncertainty_dependent=3
) #put the (price)uncertainty in the objective coefficient
else:
q_total_production = m.addVar(
lb=self.data.dat['Q_MIN'],
ub=self.data.dat['Q_MAX'],
vtype=gurobipy.GRB.CONTINUOUS,
name='q_total_production',
obj=numpy.percentile(self.data.dat['prices'][:, t, 2],
self.percentile_level) *
self.data.dat['discount_factor'][t])
else:
q_total_production = m.addVar(lb=self.data.dat['Q_MIN'],
ub=self.data.dat['Q_MAX'],
vtype=gurobipy.GRB.CONTINUOUS,
name='q_total_production')
profit = m.addVar(obj=self.data.dat['discount_factor'][t],
vtype=gurobipy.GRB.CONTINUOUS,
name='profit',
lb=-self.data.dat['MAX_COST'],
ub=self.data.dat['MAX_REV'])
revenue = m.addVar(vtype=gurobipy.GRB.CONTINUOUS,
name='revenue',
lb=0,
ub=self.data.dat['MAX_REV']) #CAN BE NEG
cost = m.addVar(vtype=gurobipy.GRB.CONTINUOUS,
name='cost',
lb=0,
ub=self.data.dat['MAX_COST'])
price = m.addVar(vtype=gurobipy.GRB.CONTINUOUS,
name='price',
lb=-20,
ub=self.data.dat['P_UPPER_BOUND'])
if self.two_factor:
lambda_sos = m.addVars(self.data.dat['num_breakpoints'],
lb=0,
ub=1,
vtype=gurobipy.GRB.CONTINUOUS,
name='lambda_sos')
# McCormick variables, bounds are defined here. Could be based on time t.
z_mcc = m.addVars([
(tt, a) for tt in range(t + 1)
for a in self.data.dat['A_ACTIVITIES']
if tt <= self.data.dat['last_stage_to_start_activity'][a]
],
lb=0,
ub=self.data.dat['P_UPPER_BOUND'],
vtype=gurobipy.GRB.CONTINUOUS,
name='z_mcc')
# ----------------------------------- #
# CONSTRAINTS
# ----------------------------------- #
if self.two_factor:
# OBJECTIVE FUNCTION Contribution
m.addConstr(profit == revenue - cost)
# PRODUCTION PROFILES
m.addConstr(
q_total_production <= self.data.dat['Q_BASE'][t] +
gurobipy.quicksum(
self.data.dat['Q_ADD'][(a, tau)][
(t - tau)] * x_activities_now[tau, a]
for a in self.data.dat['A_ACTIVITIES']
for tau in range(t + 1 -
self.data.dat['lagged_investment']) if tau
<= self.data.dat['last_stage_to_start_activity'][a] - 1))
m.addConstr(q_total_production <= self.data.dat['Q_MAX'] *
(1 - y_shutdown_now *
(1 - self.data.dat['lagged_investment']) -
y_shutdown_past * self.data.dat['lagged_investment']))
# Capacities: see variable definition
#ACTIVITIES
# Start an activity at most once per time period
m.addConstrs(
gurobipy.quicksum(x_activities_now[tt, a] for tt in range(
self.data.dat['last_stage_to_start_activity'][a])) <= 1
for a in self.data.dat['A_ACTIVITIES'])
# Maximum amount of activities that can be started each year:
m.addConstr(
gurobipy.quicksum(
x_activities_now[t, a]
for a in self.data.dat['A_ACTIVITIES']
if t <= self.data.dat['last_stage_to_start_activity'][a] -
1) <= 1)
# FIXING STATE VARIABLES FOR ALL PERIODS EXCEPT NOW
m.addConstrs(
x_activities_now[tau, a] == x_activities_past[tau, a]
for tau in self.data.dat['T_STAGES'] if tau != t
for a in self.data.dat['A_ACTIVITIES']
if tau <= self.data.dat['last_stage_to_start_activity'][a] - 1)
m.addConstr(y_shutdown_now >= y_shutdown_past)
if t == 0:
m.addConstr(y_shutdown_past == 0)
m.addConstrs(
x_activities_now[tau, a] == 0
for a in self.data.dat['A_ACTIVITIES'] for tau in range(
self.data.dat['last_stage_to_start_activity'][a])
if tau > 0)
m.addConstrs(
x_activities_past[tau, a] == 0
for a in self.data.dat['A_ACTIVITIES'] for tau in range(
self.data.dat['last_stage_to_start_activity'][a]))
# COSTS
m.addConstr(
cost >= self.data.dat['C_OPEX'][t] *
(1 - y_shutdown_now *
(1 - self.data.dat['lagged_investment']) -
y_shutdown_past * self.data.dat['lagged_investment']) +
gurobipy.quicksum(
self.data.dat['C_ACT'][a] * x_activities_now[t, a]
for a in self.data.dat['A_ACTIVITIES']
if t <= self.data.dat['last_stage_to_start_activity'][a] -
1) + self.data.dat['C_DECOM'][t] *
(y_shutdown_now - y_shutdown_past)
) #only one if we have the change
# DECOMMISSIONING
if t == (self.data.dat['num_stages'] -
1): # that is the last time period
m.addConstr(y_shutdown_now == 1)
# REVENUE & PRICES
if not self.two_factor:
if t == 0:
m.addConstr(price == np.exp(self.data.dat['xi_0'] +
self.data.dat['chi_0']))
else:
if self.markov:
m.addConstr(price == 0,
uncertainty_dependent={
'rhs': 2
}) #just to keep track of it. might remove
else:
m.addConstr(price == numpy.percentile(
self.data.dat['prices'][:, t, 2],
self.percentile_level)) #deterministic
else: #i.e. two_factor
if not self.markov: #TIME SERIES APPROACH
if t == 0:
# deterministic contraints
# define equilibrium and deviation factors previous period! (INITIALIZATION)
m.addConstr(
equilibrium_factor_now <= self.data.dat['xi_0'])
m.addConstr(
deviation_factor_now <= self.data.dat['chi_0'])
else:
error_term_eq = m.addVar(vtype=gurobipy.GRB.CONTINUOUS,
name='error_term_eq',
lb=-4,
ub=4)
error_term_dev = m.addVar(
vtype=gurobipy.GRB.CONTINUOUS,
name='error_term_dev',
lb=-4,
ub=4)
uncertainty_realization_eq = m.addConstr(
error_term_eq == 0)
uncertainty_realization_dev = m.addConstr(
error_term_dev == 0)
def f(random_state):
standard_normal_values = random_state.multivariate_normal(
mean=[0, 0],
cov=[[
self.data.dat['var_std_normal'],
self.data.dat['covariance']
],
[
self.data.dat['covariance'],
self.data.dat['var_std_normal']
]])
scaled_values = [
standard_normal_values[0] *
self.data.dat['eps_xi_par']
[self.data.dat['num_years_per_stage'][t] - 1],
standard_normal_values[1] *
self.data.dat['eps_chi_par']
[self.data.dat['num_years_per_stage'][t] - 1]
]
return_values = [0, 0]
for i in range(
2
): #preventing issues with bounds / extreme outcomes
if scaled_values[i] < self.data.dat[
'error_low'][i]:
return_values[i] = self.data.dat[
'error_low'][i]
elif scaled_values[i] > self.data.dat[
'error_low'][i]:
return_values[
i] = -self.data.dat['error_low'][i]
else:
return_values[i] = scaled_values[i]
return [round(i, precision) for i in scaled_values]
m.add_continuous_uncertainty(
uncertainty=f,
locations=[
uncertainty_realization_eq,
uncertainty_realization_dev
])
epsilon = 1 / numpy.power(
10, precision + 1) #for the rounding!
m.addConstr(
equilibrium_factor_now - equilibrium_factor_past -
self.data.dat['alpha_xi'][
self.data.dat['num_years_per_stage'][t] -
1] <= error_term_eq + 50 * epsilon)
m.addConstr(
deviation_factor_now -
deviation_factor_past * self.data.dat['beta_chi'][
self.data.dat['num_years_per_stage'][t] - 1] -
self.data.dat['alpha_chi'][
self.data.dat['num_years_per_stage'][t] -
1] <= error_term_dev + 50 * epsilon)
m.addConstr(
equilibrium_factor_now - equilibrium_factor_past -
self.data.dat['alpha_xi'][
self.data.dat['num_years_per_stage'][t] -
1] >= error_term_eq - 49 * epsilon)
m.addConstr(
deviation_factor_now -
deviation_factor_past * self.data.dat['beta_chi'][
self.data.dat['num_years_per_stage'][t] - 1] -
self.data.dat['alpha_chi'][
self.data.dat['num_years_per_stage'][t] -
1] >= error_term_dev - 49 * epsilon)
else: #two-factor markov chain approach, not necessary...
equilibrium_factor_now = m.addVar(
vtype=gurobipy.GRB.CONTINUOUS,
name='eq_fact',
lb=self.data.dat['lower_bound_eq_factor'],
ub=self.data.dat['upper_bound_eq_factor'])
deviation_factor_now = m.addVar(
vtype=gurobipy.GRB.CONTINUOUS,
name='dev_fact',
lb=self.data.dat['lower_bound_dev_factor'],
ub=-self.data.dat['lower_bound_dev_factor'])
m.addConstr(equilibrium_factor_now == 0,
uncertainty_dependent={'rhs': 0})
m.addConstr(deviation_factor_now == 0,
uncertainty_dependent={'rhs': 1})
#REVENUE & PRICES & LINEARIZATION
# McCormick
m.addConstrs(
price - self.data.dat['P_UPPER_BOUND'] *
(1 - x_activities_now[tau, a]) <= z_mcc[(tau, a)]
for a in self.data.dat['A_ACTIVITIES']
for tau in range(t + 1 -
self.data.dat['lagged_investment']) if tau
<= self.data.dat['last_stage_to_start_activity'][a] - 1)
m.addConstrs(
z_mcc[(tau, a)] <= self.data.dat['P_UPPER_BOUND'] *
x_activities_now[(tau, a)]
for a in self.data.dat['A_ACTIVITIES']
for tau in range(t + 1 -
self.data.dat['lagged_investment']) if tau
<= self.data.dat['last_stage_to_start_activity'][a] - 1)
m.addConstrs(
z_mcc[(tau, a)] <= price
for a in self.data.dat['A_ACTIVITIES']
for tau in range(t + 1 -
self.data.dat['lagged_investment']) if tau
<= self.data.dat['last_stage_to_start_activity'][a] - 1)
m.addConstr(
revenue <= self.data.dat['Q_BASE'][t] * price +
gurobipy.quicksum(
self.data.dat['Q_ADD'][(a, tau)][(t - tau)] * z_mcc[
(tau, a)] #z_mcc is x^act multiplied by price
for a in self.data.dat['A_ACTIVITIES']
for tau in range(t + 1 -
self.data.dat['lagged_investment'])
if tau <=
self.data.dat['last_stage_to_start_activity'][a] - 1))
m.addConstr(
revenue <= self.data.dat['MAX_REV'] *
(1 - y_shutdown_now *
(1 - self.data.dat['lagged_investment']) -
y_shutdown_past * self.data.dat['lagged_investment']))
# SOS2 linearization https://www.gurobi.com/documentation/8.1/refman/constraints.html#subsubsection:SOSConstraints
if not relaxation:
m.addSOS(gurobipy.GRB.SOS_TYPE2, [
lambda_sos[i]
for i in range(self.data.dat['num_breakpoints'])
])
m.addConstr(
equilibrium_factor_now +
deviation_factor_now >= gurobipy.quicksum(
self.data.dat['breakpoints_factor'][i] * lambda_sos[i]
for i in range(self.data.dat['num_breakpoints'])))
m.addConstr(price <= gurobipy.quicksum(
self.data.dat['breakpoints_price'][i] * lambda_sos[i]
for i in range(self.data.dat['num_breakpoints'])))
m.addConstr(
gurobipy.quicksum(
lambda_sos[i]
for i in range(self.data.dat['num_breakpoints'])) == 1)
#####################################
## discretization or binarization ##
#####################################
if self.markov:
model.sample_seed = self.sample_seed # seed for the sample to train Markov Chain
model.discretize(
n_Markov_states=n_markov_states,
n_sample_paths=5000, #50000
random_state=numpy.random.RandomState([
3, 3
]), #this just affects the centroid starting point for SAA
method=markov_method)
else: #TIME SERIES APPROACH
if self.two_factor:
model.discretize(
n_samples=num_samples,
random_state=888) #this is the seed and number of samples
if not relaxation:
# Binarize everything before bin_stage, standard is zero
self.model_ip.binarize(
bin_stage=self.data.dat['num_stages'],
precision=precision)
def solve_extensive_model(self, max_time):
self.model_extensive_solved = Extensive(self.model_ip)
self.model_extensive_solved.solve(outputFlag=0)
def solve_model(self, max_iter, max_time, relaxation):
if relaxation:
model = self.model_lp
else:
model = self.model_ip
# solving the model
if relaxation:
self.model_lp_solved = SDDP(self.model_lp)
self.model_lp_solved.solve(
n_processes=1,
max_iterations=max_iter,
max_stable_iterations=
20, # The maximum number of iterations to have the same deterministic bound
max_time=max_time, # hours*minutes*seconds (in seconds)
)
self.data.dat['OBJ_BOUND'] = self.model_lp_solved.db[-1]
elif not relaxation:
self.model_ip_solved = SDDiP(self.model_ip)
self.model_ip_solved.solve(
n_processes=1,
n_steps=1,
max_iterations=max_iter,
max_stable_iterations=
11, # The maximum number of iterations to have the same deterministic bound
max_time=max_time, # hours*minutes*seconds (in seconds)
n_simulations=5000, #500, -1 calculates the epv
#freq_evaluations=5, tol = 1e-3, #optimality gap
tol_diff=1e-4,
freq_comparisons=self.
freq_comp, #Turn to 1 the obtain confidence interval on policy value
query_policy_value=
False, # turn this on to get ALL the output for the graph (CI)
cuts=self.cuts, #['LG','B','SB']
)
self.data.evaluation[
'first_stage_solution'] = self.model_ip_solved.first_stage_solution
self.data.evaluation['bounds'] = self.model_ip_solved.bounds
self.data.evaluation['pv'] = self.model_ip_solved.pv
self.data.evaluation['db'] = self.model_ip_solved.db
self.data.evaluation[
'total_time'] = self.model_ip_solved.total_time
self.data.evaluation['iteration'] = self.model_ip_solved.iteration
self.get_first_stage_solution()
for key, value in self.model_ip_solved.first_stage_solution.items(
):
if value > 0.99 and value < 1.01:
print(key)
# We have to set bounds for the TS approach. If done wrong, this leads to problems with complete recourse.
def set_bounds(self, num_samples):
T = self.data.dat['num_stages']
sample_paths = self.model_lp._enumerate_sample_paths(T - 1)[
1] #returns (n_sample_paths,sample paths)
num_scenarios = len(
sample_paths) #T = 6, 6 discretizations -> 7776 scenarios..
xi_error_realization = {(t, i): 0
for t in range(1, T)
for i in range(num_samples)}
chi_error_realization = {(t, i): 0
for t in range(1, T)
for i in range(num_samples)}
for t in range(1, T):
key_xi = list(self.model_lp.models[t].uncertainty_rhs.keys())[
0] # equilibrium
key_chi = list(
self.model_lp.models[t].uncertainty_rhs.keys())[1] # dev
for i in range(num_samples):
xi_error_realization[(
t, i)] = self.model_lp.models[t].uncertainty_rhs[key_xi][i]
chi_error_realization[(
t,
i)] = self.model_lp.models[t].uncertainty_rhs[key_chi][i]
scenarios_prices = {(t, i): 0
for t in range(T) for i in range(num_scenarios)}
scenarios_xi = {(t, i): 0
for t in range(T) for i in range(num_scenarios)}
scenarios_chi = {(t, i): 0
for t in range(T) for i in range(num_scenarios)}
for i in range(num_scenarios):
for t in range(T):
if t == 0:
scenarios_xi[(t, i)] = round(self.data.dat['xi_0'], 2)
scenarios_chi[(t, i)] = round(self.data.dat['chi_0'], 2)
else:
sample = sample_paths[i][t]
scenarios_xi[(t, i)] = round(
scenarios_xi[(t - 1, i)] + self.data.dat['alpha_xi'][
self.data.dat['num_years_per_stage'][t] - 1] +
xi_error_realization[(t, sample)], 2)
scenarios_chi[(t, i)] = round(
scenarios_chi[(t - 1, i)] * (self.data.dat['beta_chi'][
self.data.dat['num_years_per_stage'][t] - 1]) +
self.data.dat['alpha_chi'][
self.data.dat['num_years_per_stage'][t] - 1] +
chi_error_realization[(t, sample)], 2)
scenarios_prices[(t, i)] = numpy.exp(scenarios_xi[(t, i)] +
scenarios_chi[(t, i)])
self.data.dat['lower_bound_eq_factor'] = round(
min(scenarios_xi.values()) - 1, 2)
self.data.dat['upper_bound_eq_factor'] = round(
max(scenarios_xi.values()) + 1, 2)
self.data.dat['lower_bound_dev_factor'] = round(
min(scenarios_chi.values()) - 1, 2)
self.data.dat['upper_bound_dev_factor'] = round(
max(scenarios_chi.values()) + 1, 2)
def get_first_stage_solution(self):
self.data.evaluation['first_stage_decision'] = []
if self.markov:
m = self.model_ip.models[0][0] # first stage problem.
else:
m = self.model_ip.models[0]
states_ = m.states #all variables controls/states
for i in range(len(states_)):
if states_[i].x == 1:
if 'x_act' in states_[i].varName or 'y_sd' in states_[
i].varName:
activity = states_[i].varName
self.data.evaluation['first_stage_decision'].append(
activity)
def print_results(self):
if os.path.exists('results.csv'):
fff = open('results.csv', 'a') # append if already exists
else:
fff = open('results.csv', 'w') # make a new file if not
print(
'Instance; Two_Factor; Markov; Num_Markov_States;sample_seed ;Num_Samples; Percentile_Level; '
' Cuts; First_Stage_Dec; Num_Its; Time; '
' UB_eval; CI_eval_L;CI_eval_U ;Gap_eval;'
'UB_eval_true; CI_eval_true_L; CI_eval_true_U; Gap_eval_true; ',
file=fff)
if len(self.data.evaluation['first_stage_decision']) > 0:
fsd = self.data.evaluation['first_stage_decision'][0]
else:
fsd = 'do_nothing'
print(self.instance,
self.two_factor,
self.markov,
self.n_markov_states,
self.sample_seed,
self.num_samples,
self.percentile_level,
self.cuts,
fsd,
self.model_ip_solved.iteration,
self.model_ip_solved.total_time,
self.data.evaluation['db_eval'],
self.data.evaluation['CI_eval'][0],
self.data.evaluation['CI_eval'][1],
self.data.evaluation['gap_eval'],
sep=';',
file=fff,
end='')
if self.markov:
print(end=';', file=fff)
print(self.data.evaluation['db_eval_true'],
self.data.evaluation['CI_eval_true'][0],
self.data.evaluation['CI_eval_true'][1],
self.data.evaluation['gap_eval_true'],
sep=';',
file=fff,
end='')
print(
'',
file=fff,
)
fff.close()
def get_average_shutdown_stage(self):
filename = 'average_shutdown_stage.csv'
if os.path.exists(filename):
ff = open(filename, 'a') # append if already exists
else:
ff = open(filename, 'w') # make a new file if not
print(
'Instance; Discount_Rate; Plugging_Cost; Increase_Plugging_cost; OPEX ;'
'Expected_ShutDown_Stage; Expected_ShutDown_Year; Expected_ShutDown_Year_Effective; gap; bound; '
'sigma_chi; sigma_xi',
file=ff)
count = 0
count2 = 0
count3 = 0
for i in range(len(self.data.evaluation['decision_matrix_true'])):
for j in range(6):
if self.data.evaluation['decision_matrix_true'].iloc[
i, j] == 'y_sd':
count += j
count2 += sum(self.data.dat['num_years_per_stage'][0:j])
count3 += sum(self.data.dat['num_years_per_stage'][0:j +
1])
expected_time = count / len(
self.data.evaluation['decision_matrix_true'])
expected_year = count2 / len(
self.data.evaluation['decision_matrix_true'])
expected_year_eff = count3 / len(
self.data.evaluation['decision_matrix_true'])
print(self.instance,
self.data.dat['r_riskfree'],
self.data.dat['DECOM_COST_FIXED'],
self.data.dat['DECOM_COST_INCREASE'],
self.data.dat['OPEX'],
expected_time,
expected_year,
expected_year_eff,
self.data.evaluation['gap_eval'],
self.data.evaluation['db_eval'],
self.data.dat['sigma_chi'],
self.data.dat['sigma_xi'],
sep=';',
file=ff)
ff.close()
def evaluate_policy(self, n_simulations):
evaluate = [False]
# When evaluating the obtained policy from TS approach we sometimes get computational issues
if self.markov:
evaluate.append(True)
for true_distribution in evaluate: #[True,False]
if true_distribution:
result = EvaluationTrue(self.model_ip)
string = '_true'
else:
result = Evaluation(self.model_ip)
string = ''
result.run(n_simulations=n_simulations,
query_stage_cost=True,
query=self.data.dat['query'])
#I could add this to the dataframe
self.data.evaluation['db_eval' + string] = result.db
self.data.evaluation['CI_eval' + string] = result.CI
self.data.evaluation['gap_eval' + string] = result.gap
self.data.evaluation['pv2_eval' + string] = result.pv
self.data.evaluation['epv_eval' + string] = result.epv
decision_matrix = pd.DataFrame(index=list(range(n_simulations)),
columns=self.data.dat['T_STAGES'])
decision_matrix = decision_matrix.fillna('-')
for i in range(n_simulations):
for (t, a) in self.data.dat['x_act_combinations']:
if result.solution["x_act[{},{}]".format(t, a)].at[i,
t] == 1:
decision_matrix.at[i, t] = a
operating = True
for t in self.data.dat['T_STAGES']:
if result.solution['y_sd'].at[i, t] == 1 and operating:
decision_matrix.at[i, t] = 'y_sd'
operating = False
self.data.evaluation['decision_matrix' + string] = decision_matrix
self.data.evaluation['prices' + string] = result.solution['price']
if self.two_factor:
self.data.evaluation['eq_fact' +
string] = result.solution['eq_fact']
self.data.evaluation['dev_fact' +
string] = result.solution['dev_fact']
#######################
### DECISION MATRIX ###
#######################
if self.print_decision_matrix:
if self.markov:
decision_matrix = self.data.evaluation['decision_matrix_true']
prices = self.data.evaluation['prices_true']
else:
decision_matrix = self.data.evaluation['decision_matrix']
prices = self.data.evaluation['prices']
summary_decision_matrix = decision_matrix.groupby(
decision_matrix.columns.tolist(), as_index=False).size()
unique_solutions = decision_matrix.drop_duplicates()
unique_solutions = unique_solutions.reset_index(drop=True)
rows_to_instances = {i: []
for i in range(len(unique_solutions))
} #rows are the unique solutions
for index, row in decision_matrix.iterrows():
for index2, row2 in unique_solutions.iterrows():
if list(row) == list(row2):
rows_to_instances[index2].append(index)
unique_solutions['count'] = 0
rows_dec_mat = list(summary_decision_matrix.index)
for i in range(len(rows_dec_mat)):
for j in range(len(unique_solutions)):
if list(summary_decision_matrix.iloc[i, 0:6]) == list(
unique_solutions.iloc[j, 0:6]):
unique_solutions['count'][j] = summary_decision_matrix[
'size'][i]
ordering = {
'new_wells8': 0,
'new_wells4': 1,
'sidetrack2': 2,
'sidetrack1': 3,
'-': 4,
'y_sd': 5
}
unique_solutions['order'] = 0
for i in [5, 4, 3, 2, 1, 0]:
unique_solutions['order'] = [
ordering[j] for j in unique_solutions[i]
]
unique_solutions = unique_solutions.sort_values(by='order',
ascending=True)
order = list(unique_solutions.index)
def manual_sorting(col):
output = []
for i in col:
for j in range(len(order)):
if i == order[j]:
output.append(j)
return output
vars = ['prices']
statistics = [
i + '_' + j for i in vars for j in ['mean', 'min', 'max']
]
stat_df = {
s: pd.DataFrame(index=range(len(unique_solutions)))
for s in statistics
}
num_stages = len(decision_matrix.columns)
for t in range(num_stages): # initialize
for stat in statistics:
stat_df[stat][str(t)] = 0.0
for i in range(len(unique_solutions)):
subset = prices.iloc[rows_to_instances[i], :]
for t in range(num_stages):
var = 'prices'
stat_df[var + '_min'][str(t)][i] = subset.iloc[:, t].min()
stat_df[var + '_max'][str(t)][i] = subset.iloc[:, t].max()
stat_df[var + '_mean'][str(t)][i] = subset.iloc[:,
t].mean()
for stat in statistics:
print(stat)
stat_df[stat]['row_number'] = list(stat_df[stat].index)
print((stat_df[stat].sort_values(by='row_number',
key=manual_sorting)))
# This takes some time.
def generate_plf(self, num_segments, n_samples, mip_gap,
time_limit): # generate piecewise linear function
self.two_factor_copy = self.two_factor
self.two_factor = False
df = self.sample_path_generator(numpy.random, n_samples)
# y = [item for sublist in df.values.tolist() for item in sublist]
y = [df[i][t][0] for i in range(len(df)) for t in range(len(df[0]))]
y.sort()
x = numpy.log(y)
plf = PLFG(x, y, num_segments)
plf.pflg_model(mip_gap, time_limit)
plf.plot()
self.data.dat['MAE'] = plf.MAE
self.data.dat['num_segments'] = num_segments
self.data.dat['num_breakpoints'] = num_segments + 1
self.data.dat['breakpoints_price'] = [
round(price, 2) for price in plf.f_b
]
self.data.dat['breakpoints_factor'] = [round(b, 2) for b in plf.b]
self.data.dat['slopes'] = plf.c
self.data.dat['intercepts'] = plf.d
self.two_factor = self.two_factor_copy
return y
def write_plf(self, filename):
with open(filename, 'w', newline='') as f:
writer = csv.writer(f, delimiter=';')
writer.writerow([self.data.dat['num_segments']])
writer.writerow(self.data.dat['breakpoints_price'])
writer.writerow(self.data.dat['breakpoints_factor'])
def read_plf(self, filename):
with open(filename, 'r', newline='') as f:
reader = csv.reader(f, delimiter=';', quoting=csv.QUOTE_NONNUMERIC)
for i, line in enumerate(reader):
if i == 0:
self.data.dat['num_segments'] = int(line[0])
self.data.dat['num_breakpoints'] = int(line[0] + 1)
elif i == 1:
self.data.dat['breakpoints_price'] = line
elif i == 2:
self.data.dat['breakpoints_factor'] = line
x <= 2
x + y_past + w - y_now = d
The third stage:
min x + 3w + 0.5y
x <= 2
x + y_past + w - y_now = d
'''
from msppy.msp import MSIP
from msppy.solver import SDDiP, Extensive
import gurobipy
T = 3
A = [100, 300]
airConditioners = MSIP(T=T, bound=0)
for t in range(T):
m = airConditioners[t]
storage_now, storage_past = m.addStateVar(vtype='I', obj=50)
produce = m.addVar(ub=200, vtype='I', obj=100)
overtime = m.addVar(vtype='I', obj=300)
m.update()
if t == 0:
m.addConstr(produce + overtime - storage_now == 100)
else:
m.addConstr(storage_past + produce + overtime - storage_now == 0,
uncertainty={'rhs': A})
m.set_probability([0.4, 0.6])
Extensive(airConditioners).solve()
SDDiP(airConditioners).solve(cuts=['B'], max_iterations=10)
m.addConstr(x[0] + x[1] >= 1.5)
m.addConstr(chi_now[0] == x[0] + 2*x[1] + slack[0])
m.addConstr(chi_now[1] == x[1] + 2*x[0] + slack[1])
else:
y = m.addVars(2, obj=[4.4,3.0], vtype='I', name='y')
m.addConstr(
2*y[0] + 3*y[1] - chi_past[0] >= 0,
uncertainty={'rhs': [-2.8,-2]}
)
m.addConstr(
4*y[0] + 1*y[1] - chi_past[1] >= 0,
uncertainty = {'rhs': [-1.2, -3]}
)
print('extensive solver: ', Extensive(MIP).solve(outputFlag=0))
MIP.binarize(bin_stage=2, precision=precision)
SDDiP(MIP).solve(cuts=['LG'], max_iterations=128)
resultTrue = EvaluationTrue(MIP)
resultTrue.run(n_simulations=100)
resultTrue.CI
####################################verification##############################################
### extensive model ##
#from gurobipy import *
#m = Model()
#y = m.addVars(2, 2, vtype = GRB.INTEGER, obj = [2.2, 1.5, 2.2, 1.5])
#x = m.addVars(2, obj = [-2.5, -2.0], name = 'x', lb = - GRB.INFINITY)
#xi = m.addVars(2, name = 'xi', lb = [1.4, 1.4], ub = [6, 7.5])
#m.update()
#m.addConstr(4 * x[0] + 5 * x[1] <= 15)
#m.addConstr(x[0] + x[1] >= 1.5)
#m.addConstr(xi[0] == x[0] + 2 * x[1])
#m.addConstr(xi[1] == x[1] + 2 * x[0])