added more documentation

sensospot_data/parameters.py

@@ -16,8 +16,12 @@ from . import columns
 PathLike = Union[str, pathlib.Path]
 
 
-def _search_params_file(folder: PathLike) -> Optional[PathLike]:
+def _search_params_file(folder: PathLike) -> Optional[pathlib.Path]:
-    """searches for a exposure settings file in a folder"""
+    """searches for a exposure settings file in a folder
+
+    folder:  directory to search
+    returns: the path to the settings file or None
+    """
     folder_path = pathlib.Path(folder)
     params_folder = folder_path / "Parameters"
     if not params_folder.is_dir():
@@ -30,6 +34,11 @@ def _search_params_file(folder: PathLike) -> Optional[PathLike]:
 
 
 def _get_channel_data(channel_node: ElementType) -> Dict[str, Any]:
+    """parses the information from an xml node of the channel settings
+
+    channel_node:   the xml node of the channel settings
+    returns:        dict with the information
+    """
     # child.tag == "ChannelConfig1"
     exposure_id = int(channel_node.tag[-1])
     # channel_description == "[Cy3|Cy5] Green"
@@ -45,7 +54,11 @@ def _get_channel_data(channel_node: ElementType) -> Dict[str, Any]:
 
 
 def _parse_measurement_params(params_file: PathLike) -> pandas.DataFrame:
-    """parses the cannel informations from a settings file"""
+    """parses the cannel informations from a settings file
+
+    params_file: path to the settings file
+    returns:     pandas DataFrame with the parsed information
+    """
     file_path = pathlib.Path(params_file)
     with file_path.open("r") as file_handle:
         tree = ElementTree.parse(file_handle)
@@ -54,7 +67,11 @@ def _parse_measurement_params(params_file: PathLike) -> pandas.DataFrame:
 
 
 def get_measurement_params(folder: PathLike) -> Optional[pandas.DataFrame]:
-    """returns measurement parameters"""
+    """searches the settings file and returns the parameters
+
+    folder: path to the folder with the measurement data
+    returns: pandas DataFrame with the parsed parameters or None
+    """
     params_file = _search_params_file(folder)
     if params_file is not None:
         return _parse_measurement_params(params_file)
@@ -62,17 +79,29 @@ def get_measurement_params(folder: PathLike) -> Optional[pandas.DataFrame]:
 
 
 def add_measurement_parameters(
-    data_frame: pandas.DataFrame, folder: PathLike
+    measurement: pandas.DataFrame, folder: PathLike
 ) -> pandas.DataFrame:
-    """adds measurement params to the data frame, if they could be parsed"""
+    """adds measurement params to the data frame, if they could be parsed
+
+    The returned DataFrame will contain two more columns for parsed time and
+    channel from the parameters file.
+
+    If the parameters could not be found, parsed or do not match up with the
+    measurement data, the additional collumns will contain NaN.
+
+    measurement: the parsed measurement data
+    returns:     the measurement data with parameters added
+    """
     params = get_measurement_params(folder)
     if params is not None:
         params_exposures = params[columns.EXPOSURE_ID].unique()
-        data_exposures = data_frame[columns.EXPOSURE_ID].unique()
+        data_exposures = measurement[columns.EXPOSURE_ID].unique()
         if set(data_exposures) == set(params_exposures):
-            return data_frame.merge(params, how="left", on=columns.EXPOSURE_ID)
+            return measurement.merge(
+                params, how="left", on=columns.EXPOSURE_ID
+            )
 
     # only executing if the parameters were not merged to the data frame
-    data_frame[columns.PARAMETERS_CHANNEL] = numpy.nan
+    measurement[columns.PARAMETERS_CHANNEL] = numpy.nan
-    data_frame[columns.PARAMETERS_TIME] = numpy.nan
+    measurement[columns.PARAMETERS_TIME] = numpy.nan
-    return data_frame
+    return measurement