BUG: Fix Series.str.zfill for ArrowDtype string arrays #61485 #61533

Original file line number	Diff line number	Diff line change
Expand Up		@@ -1008,8 +1008,8 @@ Conversion

		Strings
		^^^^^^^
	- Bug in :meth:`Series.str.zfill` raising ``AttributeError`` for :class:`ArrowDtype` (:issue:`61485`)
		- Bug in :meth:`Series.value_counts` would not respect ``sort=False`` for series having ``string`` dtype (:issue:`55224`)
	-

		Interval
		^^^^^^^^
Expand Down

7 changes: 7 additions & 0 deletions pandas/core/arrays/arrow/array.py

Show comments View file Open in desktop

Original file line number	Diff line number	Diff line change
Expand Up		@@ -2808,6 +2808,13 @@ def _str_wrap(self, width: int, **kwargs) -> Self:
		result = self._apply_elementwise(predicate)
		return self._from_pyarrow_array(pa.chunked_array(result))

	def _str_zfill(self, width: int) -> Self:
	# TODO: Replace with pc.utf8_zfill when supported by arrow
iabhi4 marked this conversation as resolved. Show resolved Hide resolved
	# Arrow ENH - https://github.com/apache/arrow/issues/46683
	predicate = lambda val: val.zfill(width)
	result = self._apply_elementwise(predicate)
	return type(self)(pa.chunked_array(result))

		@property
		def _dt_days(self) -> Self:
		return self._from_pyarrow_array(
Expand Down

3 changes: 3 additions & 0 deletions pandas/core/arrays/string_.py

Show comments View file Open in desktop

Original file line number	Diff line number	Diff line change
Expand Up		@@ -1134,3 +1134,6 @@ def _cmp_method(self, other, op):
		return res_arr

		_arith_method = _cmp_method

	def _str_zfill(self, width: int) -> Self:
	return self._str_map(lambda x: x.zfill(width))

4 changes: 2 additions & 2 deletions pandas/core/strings/accessor.py

Show comments View file Open in desktop

Original file line number	Diff line number	Diff line change
Expand Up		@@ -1912,8 +1912,8 @@ def zfill(self, width: int):
		if not is_integer(width):
		msg = f"width must be of integer type, not {type(width).__name__}"
		raise TypeError(msg)
	f=lambdax: x.zfill(width)
	result = self._data.array._str_map(f)

	result = self._data.array._str_zfill(width)
		return self._wrap_result(result)

		def slice(self, start=None, stop=None, step=None):
Expand Down

3 changes: 3 additions & 0 deletions pandas/core/strings/object_array.py

Show comments View file Open in desktop

Original file line number	Diff line number	Diff line change
Expand Up		@@ -544,3 +544,6 @@ def f(x):
		return empty_row

		return [f(val) for val in np.asarray(self)]

	def _str_zfill(self, width: int):
	return self._str_map(lambda x: x.zfill(width))

16 changes: 16 additions & 0 deletions pandas/tests/strings/test_string_array.py

Show comments View file Open in desktop

Original file line number	Diff line number	Diff line change
Expand Up		@@ -110,3 +110,19 @@ def test_string_array_extract(nullable_string_dtype):

		result = result.astype(object)
		tm.assert_equal(result, expected)


	@pytest.mark.parametrize(
	"values, width, expected",
	[
	(["a", "ab", "abc", None], 4, ["000a", "00ab", "0abc", None]),
	(["1", "-1", "+1", None], 4, ["0001", "-001", "+001", None]),
	(["1234", "-1234"], 3, ["1234", "-1234"]),
	],
	)
	def test_string_array_zfill(nullable_string_dtype, values, width, expected):
	# GH #61485
	s = Series(values, dtype=nullable_string_dtype)
	result = s.str.zfill(width)
	expected = Series(expected, dtype=nullable_string_dtype)
	tm.assert_series_equal(result, expected)

Navigation Menu