Fix SPEA2 to be not deterministic

Author: blankjul

pymoo/algorithms/moo/spea2.py

@@ -113,7 +113,7 @@ def _do(self, problem, pop, *args, n_survive=None, **kwargs):
 # ---------------------------------------------------------------------------------------------------------
 
 
-def spea_binary_tournament(pop, P, algorithm, **kwargs):
+def spea_binary_tournament(pop, P, algorithm, random_state=None, **kwargs):
     n_tournaments, n_parents = P.shape
 
     if n_parents != 2:
@@ -128,12 +128,13 @@ def spea_binary_tournament(pop, P, algorithm, **kwargs):
 
         # if at least one solution is infeasible
         if a_cv > 0.0 or b_cv > 0.0:
-            S[i] = compare(a, a_cv, b, b_cv, method='smaller_is_better', return_random_if_equal=True)
+            S[i] = compare(a, a_cv, b, b_cv, method='smaller_is_better',
+                           return_random_if_equal=True, random_state=random_state)
 
         # both solutions are feasible
         else:
             S[i] = compare(a, pop[a].get("SPEA_F"), b, pop[b].get("SPEA_F"), method='smaller_is_better',
-                           return_random_if_equal=True)
+                           return_random_if_equal=True, random_state=random_state)
 
     return S[:, None].astype(int, copy=False)
 

tests/algorithms/test_deterministic_moo.py

@@ -1,30 +1,28 @@
 import numpy as np
 import pytest
 
+from pymoo.algorithms.moo.age import AGEMOEA
+from pymoo.algorithms.moo.age2 import AGEMOEA2
 from pymoo.algorithms.moo.cmopso import CMOPSO
+from pymoo.algorithms.moo.ctaea import CTAEA
+from pymoo.algorithms.moo.dnsga2 import DNSGA2
+from pymoo.algorithms.moo.kgb import KGB
+from pymoo.algorithms.moo.moead import MOEAD
+from pymoo.algorithms.moo.moead import ParallelMOEAD
 from pymoo.algorithms.moo.mopso_cd import MOPSO_CD
 # Multi-objective algorithms
 from pymoo.algorithms.moo.nsga2 import NSGA2
-from pymoo.algorithms.moo.rnsga2 import RNSGA2
 from pymoo.algorithms.moo.nsga3 import NSGA3
-from pymoo.algorithms.moo.unsga3 import UNSGA3
+from pymoo.algorithms.moo.pinsga2 import AutomatedDM
+from pymoo.algorithms.moo.pinsga2 import PINSGA2
+from pymoo.algorithms.moo.rnsga2 import RNSGA2
 from pymoo.algorithms.moo.rnsga3 import RNSGA3
-from pymoo.algorithms.moo.moead import MOEAD
-from pymoo.algorithms.moo.age import AGEMOEA
-from pymoo.algorithms.moo.age2 import AGEMOEA2
-from pymoo.algorithms.moo.ctaea import CTAEA
-from pymoo.algorithms.moo.sms import SMSEMOA
 from pymoo.algorithms.moo.rvea import RVEA
-from pymoo.algorithms.moo.kgb import KGB
+from pymoo.algorithms.moo.sms import SMSEMOA
 from pymoo.algorithms.moo.spea2 import SPEA2
-from pymoo.algorithms.moo.dnsga2 import DNSGA2
-from pymoo.algorithms.moo.pinsga2 import PINSGA2
-from pymoo.algorithms.moo.moead import ParallelMOEAD
-
+from pymoo.algorithms.moo.unsga3 import UNSGA3
 from pymoo.optimize import minimize
 from pymoo.problems.multi import ZDT1
-from pymoo.util.ref_dirs import get_reference_directions
-from pymoo.algorithms.moo.pinsga2 import AutomatedDM
 
 
 # Simple deterministic automated decision maker for testing