Merge pull request #493 from bknueven/fix_subgradient_main

Bugfix: subgradient_main incorrectly runs PH

mpisppy/cylinders/hub.py

@@ -10,7 +10,6 @@
 import abc
 import logging
 import mpisppy.log
-from mpisppy.opt.subgradient import Subgradient
 from mpisppy.opt.aph import APH
 
 from mpisppy import MPI
@@ -27,6 +26,9 @@
 logger = logging.getLogger("mpisppy.cylinders.Hub")
 
 class Hub(SPCommunicator):
+
+    _hub_algo_best_bound_provider = False
+
     def __init__(self, spbase_object, fullcomm, strata_comm, cylinder_comm, spokes, options=None):
         super().__init__(spbase_object, fullcomm, strata_comm, cylinder_comm, options=options)
         assert len(spokes) == self.n_spokes
@@ -548,7 +550,7 @@ def is_converged(self):
             return False
 
         if not self.has_outerbound_spokes:
-            if self.opt._PHIter == 1 and not isinstance(self.opt, Subgradient):
+            if self.opt._PHIter == 1 and not self._hub_algo_best_bound_provider:
                 global_toc(
                     "Without outer bound spokes, no progress "
                     "will be made on the Best Bound")
@@ -704,6 +706,16 @@ def send_nonants(self):
         for idx in self.nonant_spoke_indices:
             self.hub_to_spoke(nonant_send_buffer, idx)
 
+
+class SubgradientHub(PHHub):
+
+    _hub_algo_best_bound_provider = True
+
+    def main(self):
+        """ SPComm gets attached in self.__init__ """
+        self.opt.subgradient_main(finalize=False)
+
+
 class APHHub(PHHub):
 
     def main(self):

mpisppy/opt/subgradient.py

@@ -37,9 +37,6 @@ def subgradient_main(self, finalize=True):
                     The "trivial bound", computed by solving the model with no
                     nonanticipativity constraints (immediately after iter 0).
         """
-        return self.ph_main(finalize=finalize)
-
-    def ph_main(self, finalize=True):
         # for use with the PH hub
         if self.options["smoothed"] != 0:
             raise RuntimeError("Cannnot use smoothing with Subgradient algorithm")

mpisppy/utils/cfg_vanilla.py

@@ -35,8 +35,7 @@
 from mpisppy.cylinders.slam_heuristic import SlamMaxHeuristic, SlamMinHeuristic
 from mpisppy.cylinders.cross_scen_spoke import CrossScenarioCutSpoke
 from mpisppy.cylinders.reduced_costs_spoke import ReducedCostsSpoke
-from mpisppy.cylinders.hub import PHHub
-from mpisppy.cylinders.hub import APHHub
+from mpisppy.cylinders.hub import PHHub, SubgradientHub, APHHub
 from mpisppy.extensions.extension import MultiExtension
 from mpisppy.extensions.fixer import Fixer
 from mpisppy.extensions.integer_relax_then_enforce import IntegerRelaxThenEnforce
@@ -195,7 +194,7 @@ def subgradient_hub(cfg,
     options["smoothed"] = 0
 
     hub_dict = {
-        "hub_class": PHHub,
+        "hub_class": SubgradientHub,
         "hub_kwargs": {"options": {"rel_gap": cfg.rel_gap,
                                    "abs_gap": cfg.abs_gap,
                                    "max_stalled_iters": cfg.max_stalled_iters}},