Bugfix for optimal objective value (#364)

* set objectives.value to fStar

* add test

* Update testing_utils.py

* addressed comment

Author: ewu63

pyoptsparse/pyOpt_solution.py

@@ -34,7 +34,7 @@ def __init__(self, optProb, xStar, fStar, lambdaStar, optInform, info):
             in the Solution object.
         """
 
-        Optimization.__init__(self, optProb.name, None)
+        super().__init__(optProb.name, None)
 
         # Copy over the variables, constraints, and objectives
         self.variables = copy.deepcopy(optProb.variables)
@@ -43,11 +43,19 @@ def __init__(self, optProb, xStar, fStar, lambdaStar, optInform, info):
         xopt = optProb._mapXtoOpt(optProb.processXtoVec(xStar))
         # Now set the x-values:
         i = 0
-        for dvGroup in self.variables:
+        for dvGroup in self.variables.keys():
             for var in self.variables[dvGroup]:
                 var.value = xopt[i]
                 i += 1
 
+        # Now set the f-values
+        if isinstance(fStar, float) or len(fStar) == 1:
+            self.objectives[list(self.objectives.keys())[0]].value = float(fStar)
+            fStar = float(fStar)
+        else:
+            for f_name, f in self.objectives.items():
+                f.value = fStar[f_name]
+
         self.optTime = info["optTime"]
         self.userObjTime = info["userObjTime"]
         self.userSensTime = info["userSensTime"]

tests/testing_utils.py

@@ -6,7 +6,6 @@
 from baseclasses.testing.assertions import assert_dict_allclose, assert_equal
 import numpy as np
 from numpy.testing import assert_allclose
-from pkg_resources import parse_version
 
 # First party modules
 from pyoptsparse import OPT, History
@@ -121,16 +120,14 @@ def assert_solution_allclose(self, sol, tol, partial_x=False):
             self.sol_index = 0
         # now we assert against the closest solution
         # objective
-        # sol.fStar was broken for earlier versions of SNOPT
-        if self.optName == "SNOPT" and parse_version(self.optVersion) < parse_version("7.7.7"):
-            sol_objectives = np.array([sol.objectives[key].value for key in sol.objectives])
-        else:
-            sol_objectives = sol.fStar
-        assert_allclose(sol_objectives, self.fStar[self.sol_index], atol=tol, rtol=tol)
+        assert_allclose(sol.fStar, self.fStar[self.sol_index], atol=tol, rtol=tol)
+        # make sure fStar and sol.objectives values match
+        assert_allclose(sol.fStar, [obj.value for obj in sol.objectives.values()], rtol=1e-12)
         # x
         assert_dict_allclose(sol.xStar, self.xStar[self.sol_index], atol=tol, rtol=tol, partial=partial_x)
         dv = sol.getDVs()
         assert_dict_allclose(dv, self.xStar[self.sol_index], atol=tol, rtol=tol, partial=partial_x)
+        assert_dict_allclose(sol.xStar, dv, rtol=1e-12)
         # lambda
         if (
             hasattr(self, "lambdaStar")