Complete hop addition calculator. Create tests in SI units. Change __…

…eq__ for Grain and Hop additions to look at the overall difference between weights and make them equal if below a half percent tolerance

brew/constants.py

@@ -146,3 +146,6 @@
 DENSITY_ETHANOL = 0.78945  # g/ml  @ 20C
 #: Alcohol by Volume Constant
 ABV_CONST = RATIO_C2H6O_TO_CO2 / ALCOHOL_SPECIFIC_GRAVITY * 100.0
+
+#: Weight Tolerance, considered equal within this range
+WEIGHT_TOLERANCE = 0.005

brew/grains.py

@@ -12,6 +12,7 @@
 from .constants import POUND_PER_KG
 from .constants import SI_TYPES
 from .constants import SI_UNITS
+from .constants import WEIGHT_TOLERANCE
 from .utilities.malt import dry_to_liquid_malt_weight
 from .utilities.malt import dry_malt_to_grain_weight
 from .utilities.malt import grain_to_dry_malt_weight
@@ -187,7 +188,7 @@ def __repr__(self):
     def __eq__(self, other):
         if not isinstance(other, self.__class__):
             return False
-        if (round(self.weight, 2) == round(other.weight, 2)) and \
+        if (abs(1.0 - self.weight / other.weight) < WEIGHT_TOLERANCE) and \
            (self.grain_type == other.grain_type) and \
            (self.units == other.units) and \
            (self.grain == other.grain):

brew/hops.py

@@ -10,6 +10,7 @@
 from .constants import OZ_PER_MG
 from .constants import SI_TYPES
 from .constants import SI_UNITS
+from .constants import WEIGHT_TOLERANCE
 from .utilities.hops import HopsUtilizationGlennTinseth
 from .validators import validate_hop_type
 from .validators import validate_optional_fields
@@ -166,7 +167,7 @@ def __eq__(self, other):
             return False
         if (self.hop == other.hop) and \
            (self.boil_time == other.boil_time) and \
-           (round(self.weight, 2) == round(other.weight, 2)) and \
+           (abs(1.0 - self.weight / other.weight) < WEIGHT_TOLERANCE) and \
            (self.hop_type == other.hop_type) and \
            (self.units == other.units):
             return True

brew/recipes.py

@@ -850,7 +850,8 @@ def get_grain_additions(self, percent_list):
             grain_additions.append(grain_add)
         return grain_additions
 
-    def get_hop_additions(self, boil_time_list,
+    def get_hop_additions(self, percent_list, boil_time_list,
+                          hop_type=HOP_TYPE_PELLET,
                           utilization_cls=HopsUtilizationGlennTinseth):
         """
         Calculate HopAdditions from list of boil times
@@ -859,8 +860,18 @@ def get_hop_additions(self, boil_time_list,
         :param HopsUtilization utilization_cls: The utilization class used for calculation
         :return: A list of Hop Additions
         :rtype: list(HopAddition)
+        :raises Exception: If sum of percentages does not equal 1.0
+        :raises Exception: If length of percent_list does not match length of self.grain_list
         :raises Exception: If length of boil_time_list does not match length of self.hop_list
         """  # nopep8
+        for percent in percent_list:
+            validate_percentage(percent)
+
+        if sum(percent_list) != 1.0:
+            raise Exception("Percentages must sum to 1.0")
+
+        if len(percent_list) != len(self.grain_list):
+            raise Exception("The length of percent_list must equal length of self.grain_list")  # nopep8
 
         if len(boil_time_list) != len(self.hop_list):
             raise Exception("The length of boil_time_list must equal length of self.hop_list")  # nopep8
@@ -871,16 +882,22 @@ def get_hop_additions(self, boil_time_list,
 
         hop_additions = []
         for index, hop in enumerate(self.hop_list):
+            percent = percent_list[index]
             boil_time = boil_time_list[index]
+
+            # Calculate utilization from boil gravity
             bg = gu_to_sg(sg_to_gu(self.original_gravity) * self.final_volume / self.start_volume)  # nopep8
             utilization = utilization_cls.get_percent_utilization(bg, boil_time)  # nopep8
+            if hop_type == HOP_TYPE_PELLET:
+                utilization *= HOP_UTILIZATION_SCALE_PELLET
 
-            num = (self.target_ibu * self.final_volume)
+            num = (self.target_ibu * percent * self.final_volume)
             den = (utilization * hop.percent_alpha_acids * hops_constant)
             weight = num / den
             hop_add = HopAddition(hop,
                                   weight=weight,
                                   boil_time=boil_time,
+                                  hop_type=hop_type,
                                   utilization_cls=utilization_cls,
                                   units=self.units)
             hop_additions.append(hop_add)

tests/test_recipes_imperial.py

@@ -336,23 +336,37 @@ def test_get_grain_additions(self):
         expected = grain_additions
         self.assertEquals(out, expected)
 
-    def test_get_grain_additions_raises_sum_invalid(self):
+    def test_get_grain_additions_raises_percent_sum_invalid(self):
         percent_list = [0.90, 0.05]
         with self.assertRaises(Exception):
             self.builder.get_grain_additions(percent_list)
 
-    def test_get_grain_additions_raises_length_mismatch(self):
+    def test_get_grain_additions_raises_percent_length_mismatch(self):
         percent_list = [0.90, 0.05, 0.05]
         with self.assertRaises(Exception):
             self.builder.get_grain_additions(percent_list)
 
     def test_get_hop_additions(self):
+        percent_list = [0.8827, 0.1173]
         boil_time_list = [60.0, 5.0]
-        out = self.builder.get_hop_additions(boil_time_list)
+        out = self.builder.get_hop_additions(percent_list, boil_time_list)
         expected = hop_additions
-        # self.assertEquals(out, expected)
+        self.assertEquals(out, expected)
+
+    def test_get_hop_additions_raises_percent_sum_invalid(self):
+        percent_list = [0.8827, 0.2173]
+        boil_time_list = [60.0, 5.0]
+        with self.assertRaises(Exception):
+            self.builder.get_hop_additions(percent_list, boil_time_list)
+
+    def test_get_hop_additions_raises_percent_length_mismatch(self):
+        percent_list = [0.8827, 0.0173, 0.10]
+        boil_time_list = [60.0, 5.0]
+        with self.assertRaises(Exception):
+            self.builder.get_hop_additions(percent_list, boil_time_list)
 
-    def test_get_hop_additions_raises_length_mismatch(self):
+    def test_get_hop_additions_raises_boil_time_length_mismatch(self):
+        percent_list = [0.8827, 0.1173]
         boil_time_list = [60.0, 5.0, 5.0]
         with self.assertRaises(Exception):
-            self.builder.get_hop_additions(boil_time_list)
+            self.builder.get_hop_additions(percent_list, boil_time_list)

tests/test_recipes_si.py

@@ -356,3 +356,28 @@ def test_get_grain_additions_raises_length_mismatch(self):
         percent_list = [0.90, 0.05, 0.05]
         with self.assertRaises(Exception):
             self.builder.get_grain_additions(percent_list)
+
+    def test_get_hop_additions(self):
+        percent_list = [0.8827, 0.1173]
+        boil_time_list = [60.0, 5.0]
+        out = self.builder.get_hop_additions(percent_list, boil_time_list)
+        expected = [ha.change_units() for ha in hop_additions]
+        self.assertEquals(out, expected)
+
+    def test_get_hop_additions_raises_percent_sum_invalid(self):
+        percent_list = [0.8827, 0.2173]
+        boil_time_list = [60.0, 5.0]
+        with self.assertRaises(Exception):
+            self.builder.get_hop_additions(percent_list, boil_time_list)
+
+    def test_get_hop_additions_raises_percent_length_mismatch(self):
+        percent_list = [0.8827, 0.0173, 0.10]
+        boil_time_list = [60.0, 5.0]
+        with self.assertRaises(Exception):
+            self.builder.get_hop_additions(percent_list, boil_time_list)
+
+    def test_get_hop_additions_raises_boil_time_length_mismatch(self):
+        percent_list = [0.8827, 0.1173]
+        boil_time_list = [60.0, 5.0, 5.0]
+        with self.assertRaises(Exception):
+            self.builder.get_hop_additions(percent_list, boil_time_list)