pyspark.pandas.Series.str.rsplit¶
-
str.
rsplit
(pat: Optional[str] = None, n: int = - 1, expand: bool = False) → Union[ps.Series, ps.DataFrame]¶ Split strings around given separator/delimiter.
Splits the string in the Series from the end, at the specified delimiter string. Equivalent to
str.rsplit()
.- Parameters
- patstr, optional
String or regular expression to split on. If not specified, split on whitespace.
- nint, default -1 (all)
Limit number of splits in output. None, 0 and -1 will be interpreted as return all splits.
- expandbool, default False
Expand the splitted strings into separate columns.
If
True
, n must be a positive integer, and return DataFrame expanding dimensionality.If
False
, return Series, containing lists of strings.
- Returns
- Series, DataFrame
Type matches caller unless expand=True (see Notes).
See also
Notes
The handling of the n keyword depends on the number of found splits:
If found splits > n, make first n splits only
If found splits <= n, make all splits
If for a certain row the number of found splits < n, append None for padding up to n if
expand=True
If using
expand=True
, Series callers return DataFrame objects with n + 1 columns.Note
Even if n is much larger than found splits, the number of columns does NOT shrink unlike pandas.
Examples
>>> s = ps.Series(["this is a regular sentence", ... "https://docs.python.org/3/tutorial/index.html", ... np.nan])
In the default setting, the string is split by whitespace.
>>> s.str.split() 0 [this, is, a, regular, sentence] 1 [https://docs.python.org/3/tutorial/index.html] 2 None dtype: object
Without the n parameter, the outputs of rsplit and split are identical.
>>> s.str.rsplit() 0 [this, is, a, regular, sentence] 1 [https://docs.python.org/3/tutorial/index.html] 2 None dtype: object
The n parameter can be used to limit the number of splits on the delimiter. The outputs of split and rsplit are different.
>>> s.str.split(n=2) 0 [this, is, a regular sentence] 1 [https://docs.python.org/3/tutorial/index.html] 2 None dtype: object
>>> s.str.rsplit(n=2) 0 [this is a, regular, sentence] 1 [https://docs.python.org/3/tutorial/index.html] 2 None dtype: object
When using
expand=True
, the split elements will expand out into separate columns. If NaN is present, it is propagated throughout the columns during the split.>>> s.str.split(n=4, expand=True) 0 1 2 3 4 0 this is a regular sentence 1 https://docs.python.org/3/tutorial/index.html None None None None 2 None None None None None
For slightly more complex use cases like splitting the html document name from a url, a combination of parameter settings can be used.
>>> s.str.rsplit("/", n=1, expand=True) 0 1 0 this is a regular sentence None 1 https://docs.python.org/3/tutorial index.html 2 None None
Remember to escape special characters when explicitly using regular expressions.
>>> s = ps.Series(["1+1=2"]) >>> s.str.split(r"\+|=", n=2, expand=True) 0 1 2 0 1 1 2