detect_nan_for_str_column¶

pyhelpers.ops.detect_nan_for_str_column(data_frame, column_names=None)[source]¶

Detect if a column with string type contains NaN values for a given dataframe.

Parameters:

data_frame (pandas.DataFrame) – A dataframe to be examined.
column_names (collections.abc.Iterable | None) – A sequence of column names to check; if column_names=None (default), all columns are checked.

Returns:

Generator yielding position index of columns that contain NaN.

Return type:

Generator

Examples:

>>> from pyhelpers.ops import detect_nan_for_str_column
>>> from pyhelpers._cache import example_dataframe
>>> dat = example_dataframe()
>>> dat
            Easting  Northing
City
London       530034    180381
Birmingham   406689    286822
Manchester   383819    398052
Leeds        582044    152953
>>> dat.loc['Leeds', 'Latitude'] = None
>>> dat
            Easting  Northing
City
London       530034  180381.0
Birmingham   406689  286822.0
Manchester   383819  398052.0
Leeds        582044       NaN
>>> nan_col_pos = detect_nan_for_str_column(data_frame=dat, column_names=None)
>>> list(nan_col_pos)
[1]