dask.dataframe.Series.isna

dask.dataframe.Series.isna¶

Series.isna()¶

Detect missing values.

This docstring was copied from pandas.core.frame.DataFrame.isna.

Some inconsistencies with the Dask version may exist.

Return a boolean same-sized object indicating if the values are NA. NA values, such as None or numpy.NaN, gets mapped to True values. Everything else gets mapped to False values. Characters such as empty strings '' or numpy.inf are not considered NA values (unless you set pandas.options.mode.use_inf_as_na = True).

Returns

DataFrame: Mask of bool values for each element in DataFrame that indicates whether an element is an NA value.

See also

DataFrame.isnull: Alias of isna.
DataFrame.notna: Boolean inverse of isna.
DataFrame.dropna: Omit axes labels with missing values.
isna: Top-level isna.

Examples

Show which entries in a DataFrame are NA.

>>> df = pd.DataFrame(dict(age=[5, 6, np.nan],  
...                        born=[pd.NaT, pd.Timestamp('1939-05-27'),
...                              pd.Timestamp('1940-04-25')],
...                        name=['Alfred', 'Batman', ''],
...                        toy=[None, 'Batmobile', 'Joker']))
>>> df  
   age       born    name        toy
0  5.0        NaT  Alfred       None
1  6.0 1939-05-27  Batman  Batmobile
2  NaN 1940-04-25              Joker

>>> df.isna()  
     age   born   name    toy
0  False   True  False   True
1  False  False  False  False
2   True  False  False  False

Show which entries in a Series are NA.

>>> ser = pd.Series([5, 6, np.nan])  
>>> ser  
0    5.0
1    6.0
2    NaN
dtype: float64

>>> ser.isna()  
0    False
1    False
2     True
dtype: bool

dask.dataframe.Series.isin

dask.dataframe.Series.isnull