do not solve demand mass balance when observed demand or availability is zero

Author: sash-ko

revpy/mfrm.py

@@ -37,10 +37,6 @@ def estimate_host_level(observed, utilities, availability, market_share):
         Estimated demand, spill and recapture for H
     """
 
-    if len(observed) != len(utilities) or len(observed) != len(availability):
-        raise InvalidInputParameters('`observed`, `utilities` and'
-                                     '`availability` must be of the same size')
-
     demand = spill = recapture = 0
 
     if observed and utilities and availability:
@@ -84,26 +80,35 @@ def estimate_class_level(observed, utilities, availability, market_share):
         Estimated demand, spill and recapture for H
     """
 
-    if len(observed) != len(utilities) or len(observed) != len(availability):
-        raise InvalidInputParameters('`observed`, `utilities` and'
-                                     '`availability` must be of the same size')
-
     _, hspill, hrecapture = estimate_host_level(observed, utilities,
                                                 availability,
                                                 market_share)
 
     estimates = {}
     total_odemand = sum(observed.values())
 
-    for product, odemand in observed.items():
+    for product in utilities.keys():
+        odemand = observed.get(product, 0)
         avail = availability.get(product, 0)
-        estimate = demand_mass_balance_c(total_odemand, odemand, avail,
-                                         hrecapture)
-        estimates[product] = {
-            'demand': estimate[0],
-            'spill': estimate[1],
-            'recapture': estimate[2]
-        }
+
+        if avail == 0 and odemand > 0:
+            raise InvalidInputParameters('Non zero observed demand with '
+                                         'zero availability')
+
+        if avail and odemand:
+            estimate = demand_mass_balance_c(total_odemand, odemand, avail,
+                                             hrecapture)
+            estimates[product] = {
+                'demand': estimate[0],
+                'spill': estimate[1],
+                'recapture': estimate[2]
+            }
+        else:
+            estimates[product] = {
+                'demand': 0,
+                'spill': 0,
+                'recapture': 0
+            }
 
     return calibrate_no_booking(estimates, observed, utilities, availability,
                                 market_share, hspill)

tests/test_mfrm.py

@@ -31,10 +31,12 @@ def test_demand_mass_balance_h(self):
         self.assertTupleEqual(round_tuple(estimations), (2.14, 0., 0.86))
 
     def test_invalid_parameters(self):
-        with self.assertRaises(InvalidInputParameters):
-            mfrm.estimate_host_level({'fare1': 3},
-                                     {'fare1': -2.8564, 'fare2': -2.5684},
-                                     {'fare1': 1, 'fare2': 0.}, 0.5)
+        """Should not rise any exception
+        """
+
+        mfrm.estimate_host_level({'fare2': 3},
+                                 {'fare1': -2.8564, 'fare2': -2.5684},
+                                 {'fare2': 1.}, 0.5)
 
 
 class MFRMTestClass(unittest.TestCase):
@@ -86,10 +88,18 @@ def test_estimate_class_level_ex1(self):
         self.assertAlmostEqual(estimations['fare2']['demand'], 2.86, 2)
 
     def test_invalid_parameters(self):
+        """Should not rise any exception
+        """
+
+        mfrm.estimate_class_level({'fare2': 3},
+                                  {'fare1': -2.8564, 'fare2': -2.5684},
+                                  {'fare2': 1.}, 0.5)
+
+    def test_non_zero_demand_zero_availability(self):
         with self.assertRaises(InvalidInputParameters):
-            mfrm.estimate_class_level({'fare1': 3},
+            mfrm.estimate_class_level({'fare1': 3, 'fare2': 1},
                                       {'fare1': -2.8564, 'fare2': -2.5684},
-                                      {'fare1': 1, 'fare2': 0.}, 0.5)
+                                      {'fare2': 1.}, 0.5)
 
 
 def round_tuple(tlp, level=2):