def _quantile(self: ArrowExtensionArrayT, qs: npt.NDArray[np.float64],
interpolation: str) -> ArrowExtensionArrayT:
"""
Compute the quantiles of self for each quantile in `qs`.
Parameters
----------
qs : np.ndarray[float64]
interpolation: str
Returns
-------
same type as self
"""
if pa_version_under4p0:
raise NotImplementedError(
"quantile only supported for pyarrow version >= 4.0")
result = pc.quantile(self._data, q=qs, interpolation=interpolation)
return type(self)(result)
def test_quantile():
arr = pa.array([1, 2, 3, 4])
result = pc.quantile(arr)
assert result.to_pylist() == [2.5]
result = pc.quantile(arr, interpolation='lower')
assert result.to_pylist() == [2]
result = pc.quantile(arr, interpolation='higher')
assert result.to_pylist() == [3]
result = pc.quantile(arr, interpolation='nearest')
assert result.to_pylist() == [3]
result = pc.quantile(arr, interpolation='midpoint')
assert result.to_pylist() == [2.5]
result = pc.quantile(arr, interpolation='linear')
assert result.to_pylist() == [2.5]
arr = pa.array([1, 2])
result = pc.quantile(arr, q=[0.25, 0.5, 0.75])
assert result.to_pylist() == [1.25, 1.5, 1.75]
result = pc.quantile(arr, q=[0.25, 0.5, 0.75], interpolation='lower')
assert result.to_pylist() == [1, 1, 1]
result = pc.quantile(arr, q=[0.25, 0.5, 0.75], interpolation='higher')
assert result.to_pylist() == [2, 2, 2]
result = pc.quantile(arr, q=[0.25, 0.5, 0.75], interpolation='midpoint')
assert result.to_pylist() == [1.5, 1.5, 1.5]
result = pc.quantile(arr, q=[0.25, 0.5, 0.75], interpolation='nearest')
assert result.to_pylist() == [1, 1, 2]
result = pc.quantile(arr, q=[0.25, 0.5, 0.75], interpolation='linear')
assert result.to_pylist() == [1.25, 1.5, 1.75]
with pytest.raises(ValueError, match="Quantile must be between 0 and 1"):
pc.quantile(arr, q=1.1)
with pytest.raises(ValueError, match="'zzz' is not a valid interpolation"):
pc.quantile(arr, interpolation='zzz')