team-10/env/Lib/site-packages/narwhals/_arrow/namespace.py
2025-08-02 07:34:44 +02:00

309 lines
12 KiB
Python

from __future__ import annotations
import operator
from functools import reduce
from itertools import chain
from typing import TYPE_CHECKING, Literal
import pyarrow as pa
import pyarrow.compute as pc
from narwhals._arrow.dataframe import ArrowDataFrame
from narwhals._arrow.expr import ArrowExpr
from narwhals._arrow.selectors import ArrowSelectorNamespace
from narwhals._arrow.series import ArrowSeries
from narwhals._arrow.utils import cast_to_comparable_string_types
from narwhals._compliant import CompliantThen, EagerNamespace, EagerWhen
from narwhals._expression_parsing import (
combine_alias_output_names,
combine_evaluate_output_names,
)
from narwhals._utils import Implementation
if TYPE_CHECKING:
from collections.abc import Sequence
from narwhals._arrow.typing import ArrayOrScalar, ChunkedArrayAny, Incomplete
from narwhals._compliant.typing import ScalarKwargs
from narwhals._utils import Version
from narwhals.typing import IntoDType, NonNestedLiteral
class ArrowNamespace(
EagerNamespace[ArrowDataFrame, ArrowSeries, ArrowExpr, pa.Table, "ChunkedArrayAny"]
):
_implementation = Implementation.PYARROW
@property
def _dataframe(self) -> type[ArrowDataFrame]:
return ArrowDataFrame
@property
def _expr(self) -> type[ArrowExpr]:
return ArrowExpr
@property
def _series(self) -> type[ArrowSeries]:
return ArrowSeries
def __init__(self, *, version: Version) -> None:
self._version = version
def len(self) -> ArrowExpr:
# coverage bug? this is definitely hit
return self._expr( # pragma: no cover
lambda df: [
ArrowSeries.from_iterable([len(df.native)], name="len", context=self)
],
depth=0,
function_name="len",
evaluate_output_names=lambda _df: ["len"],
alias_output_names=None,
version=self._version,
)
def lit(self, value: NonNestedLiteral, dtype: IntoDType | None) -> ArrowExpr:
def _lit_arrow_series(_: ArrowDataFrame) -> ArrowSeries:
arrow_series = ArrowSeries.from_iterable(
data=[value], name="literal", context=self
)
if dtype:
return arrow_series.cast(dtype)
return arrow_series
return self._expr(
lambda df: [_lit_arrow_series(df)],
depth=0,
function_name="lit",
evaluate_output_names=lambda _df: ["literal"],
alias_output_names=None,
version=self._version,
)
def all_horizontal(self, *exprs: ArrowExpr, ignore_nulls: bool) -> ArrowExpr:
def func(df: ArrowDataFrame) -> list[ArrowSeries]:
series = chain.from_iterable(expr(df) for expr in exprs)
align = self._series._align_full_broadcast
it = (
(s.fill_null(True, None, None) for s in series) # noqa: FBT003
if ignore_nulls
else series
)
return [reduce(operator.and_, align(*it))]
return self._expr._from_callable(
func=func,
depth=max(x._depth for x in exprs) + 1,
function_name="all_horizontal",
evaluate_output_names=combine_evaluate_output_names(*exprs),
alias_output_names=combine_alias_output_names(*exprs),
context=self,
)
def any_horizontal(self, *exprs: ArrowExpr, ignore_nulls: bool) -> ArrowExpr:
def func(df: ArrowDataFrame) -> list[ArrowSeries]:
series = chain.from_iterable(expr(df) for expr in exprs)
align = self._series._align_full_broadcast
it = (
(s.fill_null(False, None, None) for s in series) # noqa: FBT003
if ignore_nulls
else series
)
return [reduce(operator.or_, align(*it))]
return self._expr._from_callable(
func=func,
depth=max(x._depth for x in exprs) + 1,
function_name="any_horizontal",
evaluate_output_names=combine_evaluate_output_names(*exprs),
alias_output_names=combine_alias_output_names(*exprs),
context=self,
)
def sum_horizontal(self, *exprs: ArrowExpr) -> ArrowExpr:
def func(df: ArrowDataFrame) -> list[ArrowSeries]:
it = chain.from_iterable(expr(df) for expr in exprs)
series = (s.fill_null(0, strategy=None, limit=None) for s in it)
align = self._series._align_full_broadcast
return [reduce(operator.add, align(*series))]
return self._expr._from_callable(
func=func,
depth=max(x._depth for x in exprs) + 1,
function_name="sum_horizontal",
evaluate_output_names=combine_evaluate_output_names(*exprs),
alias_output_names=combine_alias_output_names(*exprs),
context=self,
)
def mean_horizontal(self, *exprs: ArrowExpr) -> ArrowExpr:
int_64 = self._version.dtypes.Int64()
def func(df: ArrowDataFrame) -> list[ArrowSeries]:
expr_results = list(chain.from_iterable(expr(df) for expr in exprs))
align = self._series._align_full_broadcast
series = align(
*(s.fill_null(0, strategy=None, limit=None) for s in expr_results)
)
non_na = align(*(1 - s.is_null().cast(int_64) for s in expr_results))
return [reduce(operator.add, series) / reduce(operator.add, non_na)]
return self._expr._from_callable(
func=func,
depth=max(x._depth for x in exprs) + 1,
function_name="mean_horizontal",
evaluate_output_names=combine_evaluate_output_names(*exprs),
alias_output_names=combine_alias_output_names(*exprs),
context=self,
)
def min_horizontal(self, *exprs: ArrowExpr) -> ArrowExpr:
def func(df: ArrowDataFrame) -> list[ArrowSeries]:
align = self._series._align_full_broadcast
init_series, *series = list(chain.from_iterable(expr(df) for expr in exprs))
init_series, *series = align(init_series, *series)
native_series = reduce(
pc.min_element_wise, [s.native for s in series], init_series.native
)
return [
ArrowSeries(native_series, name=init_series.name, version=self._version)
]
return self._expr._from_callable(
func=func,
depth=max(x._depth for x in exprs) + 1,
function_name="min_horizontal",
evaluate_output_names=combine_evaluate_output_names(*exprs),
alias_output_names=combine_alias_output_names(*exprs),
context=self,
)
def max_horizontal(self, *exprs: ArrowExpr) -> ArrowExpr:
def func(df: ArrowDataFrame) -> list[ArrowSeries]:
align = self._series._align_full_broadcast
init_series, *series = list(chain.from_iterable(expr(df) for expr in exprs))
init_series, *series = align(init_series, *series)
native_series = reduce(
pc.max_element_wise, [s.native for s in series], init_series.native
)
return [
ArrowSeries(native_series, name=init_series.name, version=self._version)
]
return self._expr._from_callable(
func=func,
depth=max(x._depth for x in exprs) + 1,
function_name="max_horizontal",
evaluate_output_names=combine_evaluate_output_names(*exprs),
alias_output_names=combine_alias_output_names(*exprs),
context=self,
)
def _concat_diagonal(self, dfs: Sequence[pa.Table], /) -> pa.Table:
if self._backend_version >= (14,):
return pa.concat_tables(dfs, promote_options="default")
return pa.concat_tables(dfs, promote=True) # pragma: no cover
def _concat_horizontal(self, dfs: Sequence[pa.Table], /) -> pa.Table:
names = list(chain.from_iterable(df.column_names for df in dfs))
arrays = list(chain.from_iterable(df.itercolumns() for df in dfs))
return pa.Table.from_arrays(arrays, names=names)
def _concat_vertical(self, dfs: Sequence[pa.Table], /) -> pa.Table:
cols_0 = dfs[0].column_names
for i, df in enumerate(dfs[1:], start=1):
cols_current = df.column_names
if cols_current != cols_0:
msg = (
"unable to vstack, column names don't match:\n"
f" - dataframe 0: {cols_0}\n"
f" - dataframe {i}: {cols_current}\n"
)
raise TypeError(msg)
return pa.concat_tables(dfs)
@property
def selectors(self) -> ArrowSelectorNamespace:
return ArrowSelectorNamespace.from_namespace(self)
def when(self, predicate: ArrowExpr) -> ArrowWhen:
return ArrowWhen.from_expr(predicate, context=self)
def concat_str(
self, *exprs: ArrowExpr, separator: str, ignore_nulls: bool
) -> ArrowExpr:
def func(df: ArrowDataFrame) -> list[ArrowSeries]:
align = self._series._align_full_broadcast
compliant_series_list = align(
*(chain.from_iterable(expr(df) for expr in exprs))
)
name = compliant_series_list[0].name
null_handling: Literal["skip", "emit_null"] = (
"skip" if ignore_nulls else "emit_null"
)
it, separator_scalar = cast_to_comparable_string_types(
*(s.native for s in compliant_series_list), separator=separator
)
# NOTE: stubs indicate `separator` must also be a `ChunkedArray`
# Reality: `str` is fine
concat_str: Incomplete = pc.binary_join_element_wise
compliant = self._series(
concat_str(*it, separator_scalar, null_handling=null_handling),
name=name,
version=self._version,
)
return [compliant]
return self._expr._from_callable(
func=func,
depth=max(x._depth for x in exprs) + 1,
function_name="concat_str",
evaluate_output_names=combine_evaluate_output_names(*exprs),
alias_output_names=combine_alias_output_names(*exprs),
context=self,
)
def coalesce(self, *exprs: ArrowExpr) -> ArrowExpr:
def func(df: ArrowDataFrame) -> list[ArrowSeries]:
align = self._series._align_full_broadcast
init_series, *series = align(*chain.from_iterable(expr(df) for expr in exprs))
return [
ArrowSeries(
pc.coalesce(init_series.native, *(s.native for s in series)),
name=init_series.name,
version=self._version,
)
]
return self._expr._from_callable(
func=func,
depth=max(x._depth for x in exprs) + 1,
function_name="coalesce",
evaluate_output_names=combine_evaluate_output_names(*exprs),
alias_output_names=combine_alias_output_names(*exprs),
context=self,
)
class ArrowWhen(EagerWhen[ArrowDataFrame, ArrowSeries, ArrowExpr, "ChunkedArrayAny"]):
@property
def _then(self) -> type[ArrowThen]:
return ArrowThen
def _if_then_else(
self,
when: ChunkedArrayAny,
then: ChunkedArrayAny,
otherwise: ArrayOrScalar | NonNestedLiteral,
/,
) -> ChunkedArrayAny:
otherwise = pa.nulls(len(when), then.type) if otherwise is None else otherwise
return pc.if_else(when, then, otherwise)
class ArrowThen(
CompliantThen[ArrowDataFrame, ArrowSeries, ArrowExpr, ArrowWhen], ArrowExpr
):
_depth: int = 0
_scalar_kwargs: ScalarKwargs = {} # noqa: RUF012
_function_name: str = "whenthen"