Merge a5cb8a5 into c10d6d5

openmdao/core/component.py

@@ -1259,6 +1259,13 @@ def _declare_partials(self, of, wrt, dct):
                 meta['cols'] = cols
                 meta['shape'] = shape = (abs2meta[abs_key[0]]['size'], abs2meta[abs_key[1]]['size'])
 
+                if shape[0] == 0 or shape[1] == 0:
+                    msg = "{}: '{}' is an array of size 0"
+                    if shape[0] == 0:
+                        raise ValueError(msg.format(self.msginfo, abs_key[0]))
+                    elif shape[1] == 0:
+                        raise ValueError(msg.format(self.msginfo, abs_key[1]))
+
                 if val is None:
                     # we can only get here if rows is None  (we're not sparse list format)
                     meta['value'] = np.zeros(shape)

openmdao/core/tests/test_coloring.py

@@ -319,6 +319,88 @@ def test_dynamic_fwd_simul_coloring_snopt_approx_fd(self):
         self.assertEqual((p.model._solve_nl_count - 2) / 22,
                          (p_color.model._solve_nl_count - 2 - 66) / 6)
 
+    def test_size_zero_array_in_component(self):
+        class DynamicPartialsComp(om.ExplicitComponent):
+            def __init__(self, size):
+                super(DynamicPartialsComp, self).__init__()
+                self.size = size
+                self.num_computes = 0
+
+            def setup(self):
+                self.add_input('y', np.ones(self.size))
+                self.add_input('x', np.ones(self.size))
+                self.add_output('g', np.ones(self.size))
+
+                self.declare_partials('*', '*', method='cs')
+
+                # turn on dynamic partial coloring
+                self.declare_coloring(wrt='*', method='cs', perturb_size=1e-5, num_full_jacs=2, tol=1e-20,
+                                    orders=20, show_summary=True, show_sparsity=True)
+
+            def compute(self, inputs, outputs):
+                outputs['g'] = np.arctan(inputs['y'] / inputs['x'])
+                self.num_computes += 1
+
+        SIZE = 0
+        p = om.Problem()
+
+        arctan_yox = p.model.add_subsystem('arctan_yox', DynamicPartialsComp(SIZE))
+
+        p.driver = om.ScipyOptimizeDriver()
+        p.driver.options['optimizer'] = 'SLSQP'
+        p.driver.options['disp'] = False
+
+        p.driver.declare_coloring(show_summary=True, show_sparsity=True)
+
+        p.setup(mode='fwd')
+
+        with self.assertRaises(Exception) as context:
+            p.run_driver()
+        self.assertEqual(str(context.exception),
+                         "DynamicPartialsComp (arctan_yox): 'arctan_yox.g' is an array of size 0")
+
+    def test_size_zero_array_declare_partials(self):
+        class DynamicPartialsComp(om.ExplicitComponent):
+            def __init__(self, size):
+                super(DynamicPartialsComp, self).__init__()
+                self.size = size
+                self.num_computes = 0
+
+            def setup(self):
+                self.add_input('y', np.ones(self.size))
+                self.add_input('x', np.ones(self.size))
+                self.add_output('g', np.ones(self.size))
+                self.add_output('r', np.ones(1))
+
+                self.declare_partials('r', 'y', method='cs')
+
+                # turn on dynamic partial coloring
+                self.declare_coloring(wrt='*', method='cs', perturb_size=1e-5, num_full_jacs=2, tol=1e-20,
+                                    orders=20, show_summary=True, show_sparsity=True)
+
+            def compute(self, inputs, outputs):
+                outputs['g'] = np.arctan(inputs['y'] / inputs['x'])
+                self.num_computes += 1
+
+        SIZE = 0
+        p = om.Problem()
+
+        arctan_yox = p.model.add_subsystem('arctan_yox', DynamicPartialsComp(SIZE))
+
+        p.driver = om.ScipyOptimizeDriver()
+        p.driver.options['optimizer'] = 'SLSQP'
+        p.driver.options['disp'] = False
+
+        p.driver.declare_coloring(show_summary=True, show_sparsity=True)
+
+        p.setup(mode='fwd')
+
+        with self.assertRaises(Exception) as context:
+            p.run_driver()
+        self.assertEqual(str(context.exception),
+                         "DynamicPartialsComp (arctan_yox): 'arctan_yox.y' is an array of size 0")
+
+
     def test_dynamic_total_coloring_pyoptsparse_slsqp_auto(self):
         try:
             from pyoptsparse import OPT