Parameterises test_utils.py::test_create_empty_dataframe() so that all three possible empty dataframes are now tested.
Renames create_empty_dataframe() parameter index > index_col to avoid confusion with Python and Pandas index methods.
Explicitly calls create_empty_dataframe() with the column_set and index_col in each instance rather than relying on defaults when an empty grainstats_df is required.
Further at the end of process_scan() empty dataframes of all types were incorrectly generated as no types were specified for any, these now generate the correct type for each required data frame.
test_utils.py::test_create_empty_dataframe()so that all three possible empty dataframes are now tested.create_empty_dataframe()parameterindex>index_colto avoid confusion with Python and Pandasindexmethods.create_empty_dataframe()with thecolumn_setandindex_colin each instance rather than relying on defaults when an emptygrainstats_dfis required.process_scan()empty dataframes of all types were incorrectly generated as no types were specified for any, these now generate the correct type for each required data frame.