Merge branch 'dmp_refactoring' into 'develop'

dmpscheme refactorings

See merge request !427

saqc/core/translation/dmpscheme.py

@@ -78,6 +78,28 @@ class DmpScheme(TranslationScheme):
     def __init__(self):
         super().__init__(forward=self._FORWARD, backward=self._BACKWARD)
 
+    def toHistory(self, field_flags: pd.DataFrame):
+        """
+        Translate a single field of external ``Flags`` to a ``History``
+        """
+        field_history = History(field_flags.index)
+
+        for (flag, cause, comment), values in field_flags.groupby(_QUALITY_LABELS):
+            try:
+                comment = json.loads(comment)
+            except json.decoder.JSONDecodeError:
+                comment = {"test": "unknown", "comment": ""}
+
+            histcol = pd.Series(np.nan, index=field_flags.index)
+            histcol.loc[values.index] = self(flag)
+
+            meta = {
+                "func": comment["test"],
+                "kwargs": {"comment": comment["comment"], "cause": cause},
+            }
+            field_history.append(histcol, meta=meta)
+        return field_history
+
     def forward(self, df: pd.DataFrame) -> Flags:
         """
         Translate from 'external flags' to 'internal flags'
@@ -96,27 +118,8 @@ class DmpScheme(TranslationScheme):
 
         data = {}
 
-        for field in df.columns.get_level_values(0):
-
-            field_flags = df[field]
-            field_history = History(field_flags.index)
-
-            for (flag, cause, comment), values in field_flags.groupby(_QUALITY_LABELS):
-                try:
-                    comment = json.loads(comment)
-                except json.decoder.JSONDecodeError:
-                    comment = {"test": "unknown", "comment": ""}
-
-                histcol = pd.Series(np.nan, index=field_flags.index)
-                histcol.loc[values.index] = self(flag)
-
-                meta = {
-                    "func": comment["test"],
-                    "kwargs": {"comment": comment["comment"], "cause": cause},
-                }
-                field_history.append(histcol, meta=meta)
-
-            data[str(field)] = field_history
+        for field in df.columns.get_level_values(0).drop_duplicates():
+            data[str(field)] = self.toHistory(df[field])
 
         return Flags(data)