Merge pull request #3387 from jsiirola/pprint-nonfinite-param

Support `Param.pprint()` for non-finite Params

Author: blnicho

pyomo/core/base/param.py

@@ -894,8 +894,12 @@ def _pprint(self):
             dataGen = lambda k, v: [v._value]
         else:
             dataGen = lambda k, v: [v]
+        if self.index_set().isfinite() or self._default_val is Param.NoValue:
+            _len = len(self)
+        else:
+            _len = 'inf'
         headers = [
-            ("Size", len(self)),
+            ("Size", _len),
             ("Index", self._index_set if self.is_indexed() else None),
             ("Domain", self.domain.name),
             ("Default", default),

pyomo/core/tests/unit/test_param.py

@@ -1561,6 +1561,70 @@ def test_scalar_set_mutable_when_not_present(self):
         m.p = 20
         self.assertEqual(m.x_p.bounds, (0, 20))
 
+    def test_nonfinite_pprint(self):
+        m = ConcreteModel()
+
+        # Test from #3379
+        m.p = Param(Any, default=1)
+        self.assertEqual(m.p['foo'], 1)
+        OUT = StringIO()
+        m.p.pprint(OUT)
+        self.assertEqual(
+            OUT.getvalue(),
+            "p : Size=inf, Index=Any, Domain=Any, Default=1, Mutable=False\n"
+            "    Key : Value\n",
+        )
+
+        # Other useful checks
+        m.q = Param(Any, default=1, initialize={1: 2, 'a': 3, 'bb': 4})
+        OUT = StringIO()
+        m.q.pprint(OUT)
+        self.assertEqual(
+            OUT.getvalue(),
+            "q : Size=inf, Index=Any, Domain=Any, Default=1, Mutable=False\n"
+            "    Key : Value\n"
+            "      1 :     2\n"
+            "      a :     3\n"
+            "     bb :     4\n",
+        )
+
+        m.r = Param(Any, initialize={1: 2, 'a': 3, 'bb': 4})
+        OUT = StringIO()
+        m.r.pprint(OUT)
+        self.assertEqual(
+            OUT.getvalue(),
+            "r : Size=3, Index=Any, Domain=Any, Default=None, Mutable=False\n"
+            "    Key : Value\n"
+            "      1 :     2\n"
+            "      a :     3\n"
+            "     bb :     4\n",
+        )
+
+        # Other useful (mutable) checks
+        m.q = Param(Any, default=1, mutable=True, initialize={1: 2, 'a': 3, 'bb': 4})
+        OUT = StringIO()
+        m.q.pprint(OUT)
+        self.assertEqual(
+            OUT.getvalue(),
+            "q : Size=inf, Index=Any, Domain=Any, Default=1, Mutable=True\n"
+            "    Key : Value\n"
+            "      1 :     2\n"
+            "      a :     3\n"
+            "     bb :     4\n",
+        )
+
+        m.r = Param(Any, mutable=True, initialize={1: 2, 'a': 3, 'bb': 4})
+        OUT = StringIO()
+        m.r.pprint(OUT)
+        self.assertEqual(
+            OUT.getvalue(),
+            "r : Size=3, Index=Any, Domain=Any, Default=None, Mutable=True\n"
+            "    Key : Value\n"
+            "      1 :     2\n"
+            "      a :     3\n"
+            "     bb :     4\n",
+        )
+
 
 def createNonIndexedParamMethod(func, init_xy, new_xy, tol=1e-10):
     def testMethod(self):