Fix bug44

docs/reference/analytics.rst

@@ -37,6 +37,8 @@
       :type data: list
       :param days: 天數
       :type days: int
+      :param skipna: 是否過濾缺失資料
+      :type: bool
 
       分析 ``data`` 中之 ``days`` 日之平均數::
 

test/test_analytics.py

@@ -49,6 +49,14 @@ def test_moving_average(self):
         self.assertEqual(ng_result, legacy_result)
         self.assertEqual(ng_result, [55.0, 65.0, 72.5])
 
+        data = [10, 11, 12, 15, 10, 12, None, 10, 5]
+
+        # Legacy moving_average will affect data argument's data
+        ng_result = self.ng.moving_average(data, 2)
+        legacy_result = self.legacy.moving_average(data, 2)
+        self.assertEqual(ng_result, legacy_result)
+        self.assertEqual(ng_result, [10.5, 11.5, 13.5, 12.5, 11.0, 11.0, 7.5])
+
     def test_ma_bias_ratio(self):
         data = [50, 60, 70, 75, 80, 88, 102, 105, 106]
         self.ng.price = data

twstock/analytics.py

@@ -13,7 +13,10 @@ def continuous(self, data):
                 break
         return cont * diff[0]
 
-    def moving_average(self, data, days):
+    def moving_average(self, data, days, skipna=True):
+        if skipna:
+            data = [x for x in data if x is not None]
+
         result = []
         data = data[:]
         for _ in range(len(data) - days + 1):