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

1169 lines
40 KiB
Python

from __future__ import annotations
from collections.abc import Mapping
from functools import partial
from operator import methodcaller
from typing import TYPE_CHECKING, Any, Callable, Generic, Literal, Protocol
from narwhals._compliant.any_namespace import (
CatNamespace,
DateTimeNamespace,
ListNamespace,
NameNamespace,
StringNamespace,
StructNamespace,
)
from narwhals._compliant.namespace import CompliantNamespace
from narwhals._compliant.typing import (
AliasName,
AliasNames,
CompliantExprT_co,
CompliantFrameT,
CompliantLazyFrameT,
CompliantSeriesOrNativeExprT_co,
EagerDataFrameT,
EagerExprT,
EagerSeriesT,
LazyExprT,
NativeExprT,
)
from narwhals._utils import _StoresCompliant
from narwhals.dependencies import get_numpy, is_numpy_array
if TYPE_CHECKING:
from collections.abc import Mapping, Sequence
from typing_extensions import Self, TypeIs
from narwhals._compliant.namespace import CompliantNamespace, EagerNamespace
from narwhals._compliant.series import CompliantSeries
from narwhals._compliant.typing import AliasNames, EvalNames, EvalSeries, ScalarKwargs
from narwhals._expression_parsing import ExprKind, ExprMetadata
from narwhals._utils import Implementation, Version, _LimitedContext
from narwhals.typing import (
FillNullStrategy,
IntoDType,
NonNestedLiteral,
NumericLiteral,
RankMethod,
RollingInterpolationMethod,
TemporalLiteral,
TimeUnit,
)
__all__ = ["CompliantExpr", "DepthTrackingExpr", "EagerExpr", "LazyExpr", "NativeExpr"]
class NativeExpr(Protocol):
"""An `Expr`-like object from a package with [Lazy-only support](https://narwhals-dev.github.io/narwhals/extending/#levels-of-support).
Protocol members are chosen *purely* for matching statically - as they
are common to all currently supported packages.
"""
def between(self, *args: Any, **kwds: Any) -> Any: ...
def isin(self, *args: Any, **kwds: Any) -> Any: ...
class CompliantExpr(Protocol[CompliantFrameT, CompliantSeriesOrNativeExprT_co]):
_implementation: Implementation
_version: Version
_evaluate_output_names: EvalNames[CompliantFrameT]
_alias_output_names: AliasNames | None
_metadata: ExprMetadata | None
def __call__(
self, df: CompliantFrameT
) -> Sequence[CompliantSeriesOrNativeExprT_co]: ...
def __narwhals_expr__(self) -> None: ...
def __narwhals_namespace__(self) -> CompliantNamespace[CompliantFrameT, Self]: ...
@classmethod
def from_column_names(
cls,
evaluate_column_names: EvalNames[CompliantFrameT],
/,
*,
context: _LimitedContext,
) -> Self: ...
@classmethod
def from_column_indices(
cls, *column_indices: int, context: _LimitedContext
) -> Self: ...
@staticmethod
def _eval_names_indices(indices: Sequence[int], /) -> EvalNames[CompliantFrameT]:
def fn(df: CompliantFrameT) -> Sequence[str]:
column_names = df.columns
return [column_names[i] for i in indices]
return fn
def is_null(self) -> Self: ...
def abs(self) -> Self: ...
def all(self) -> Self: ...
def any(self) -> Self: ...
def alias(self, name: str) -> Self: ...
def cast(self, dtype: IntoDType) -> Self: ...
def count(self) -> Self: ...
def min(self) -> Self: ...
def max(self) -> Self: ...
def mean(self) -> Self: ...
def sum(self) -> Self: ...
def median(self) -> Self: ...
def skew(self) -> Self: ...
def kurtosis(self) -> Self: ...
def std(self, *, ddof: int) -> Self: ...
def var(self, *, ddof: int) -> Self: ...
def n_unique(self) -> Self: ...
def null_count(self) -> Self: ...
def drop_nulls(self) -> Self: ...
def fill_null(
self,
value: Self | NonNestedLiteral,
strategy: FillNullStrategy | None,
limit: int | None,
) -> Self: ...
def diff(self) -> Self: ...
def exp(self) -> Self: ...
def sqrt(self) -> Self: ...
def unique(self) -> Self: ...
def len(self) -> Self: ...
def log(self, base: float) -> Self: ...
def round(self, decimals: int) -> Self: ...
def mode(self) -> Self: ...
def shift(self, n: int) -> Self: ...
def is_finite(self) -> Self: ...
def is_nan(self) -> Self: ...
def is_unique(self) -> Self: ...
def is_first_distinct(self) -> Self: ...
def is_last_distinct(self) -> Self: ...
def cum_sum(self, *, reverse: bool) -> Self: ...
def cum_count(self, *, reverse: bool) -> Self: ...
def cum_min(self, *, reverse: bool) -> Self: ...
def cum_max(self, *, reverse: bool) -> Self: ...
def cum_prod(self, *, reverse: bool) -> Self: ...
def is_in(self, other: Any) -> Self: ...
def rank(self, method: RankMethod, *, descending: bool) -> Self: ...
def replace_strict(
self,
old: Sequence[Any] | Mapping[Any, Any],
new: Sequence[Any],
*,
return_dtype: IntoDType | None,
) -> Self: ...
def over(self, partition_by: Sequence[str], order_by: Sequence[str]) -> Self: ...
def quantile(
self, quantile: float, interpolation: RollingInterpolationMethod
) -> Self: ...
def map_batches(
self,
function: Callable[[CompliantSeries[Any]], CompliantExpr[Any, Any]],
return_dtype: IntoDType | None,
) -> Self: ...
def clip(
self,
lower_bound: Self | NumericLiteral | TemporalLiteral | None,
upper_bound: Self | NumericLiteral | TemporalLiteral | None,
) -> Self: ...
def ewm_mean(
self,
*,
com: float | None,
span: float | None,
half_life: float | None,
alpha: float | None,
adjust: bool,
min_samples: int,
ignore_nulls: bool,
) -> Self: ...
def rolling_sum(
self, window_size: int, *, min_samples: int, center: bool
) -> Self: ...
def rolling_mean(
self, window_size: int, *, min_samples: int, center: bool
) -> Self: ...
def rolling_var(
self, window_size: int, *, min_samples: int, center: bool, ddof: int
) -> Self: ...
def rolling_std(
self, window_size: int, *, min_samples: int, center: bool, ddof: int
) -> Self: ...
def __and__(self, other: Any) -> Self: ...
def __or__(self, other: Any) -> Self: ...
def __add__(self, other: Any) -> Self: ...
def __sub__(self, other: Any) -> Self: ...
def __mul__(self, other: Any) -> Self: ...
def __floordiv__(self, other: Any) -> Self: ...
def __truediv__(self, other: Any) -> Self: ...
def __mod__(self, other: Any) -> Self: ...
def __pow__(self, other: Any) -> Self: ...
def __gt__(self, other: Any) -> Self: ...
def __ge__(self, other: Any) -> Self: ...
def __lt__(self, other: Any) -> Self: ...
def __le__(self, other: Any) -> Self: ...
def __invert__(self) -> Self: ...
def broadcast(
self, kind: Literal[ExprKind.AGGREGATION, ExprKind.LITERAL]
) -> Self: ...
def _is_multi_output_unnamed(self) -> bool:
"""Return `True` for multi-output aggregations without names.
For example, column `'a'` only appears in the output as a grouping key:
df.group_by('a').agg(nw.all().sum())
It does not get included in:
nw.all().sum().
"""
assert self._metadata is not None # noqa: S101
return self._metadata.expansion_kind.is_multi_unnamed()
def _evaluate_aliases(
self: CompliantExpr[CompliantFrameT, Any], frame: CompliantFrameT, /
) -> Sequence[str]:
names = self._evaluate_output_names(frame)
return alias(names) if (alias := self._alias_output_names) else names
@property
def str(self) -> StringNamespace[Self]: ...
@property
def name(self) -> NameNamespace[Self]: ...
@property
def dt(self) -> DateTimeNamespace[Self]: ...
@property
def cat(self) -> CatNamespace[Self]: ...
@property
def list(self) -> ListNamespace[Self]: ...
@property
def struct(self) -> StructNamespace[Self]: ...
class DepthTrackingExpr(
CompliantExpr[CompliantFrameT, CompliantSeriesOrNativeExprT_co],
Protocol[CompliantFrameT, CompliantSeriesOrNativeExprT_co],
):
_depth: int
_function_name: str
@classmethod
def from_column_names(
cls: type[Self],
evaluate_column_names: EvalNames[CompliantFrameT],
/,
*,
context: _LimitedContext,
function_name: str = "",
) -> Self: ...
def _is_elementary(self) -> bool:
"""Check if expr is elementary.
Examples:
- nw.col('a').mean() # depth 1
- nw.mean('a') # depth 1
- nw.len() # depth 0
as opposed to, say
- nw.col('a').filter(nw.col('b')>nw.col('c')).max()
Elementary expressions are the only ones supported properly in
pandas, PyArrow, and Dask.
"""
return self._depth < 2
def __repr__(self) -> str: # pragma: no cover
return f"{type(self).__name__}(depth={self._depth}, function_name={self._function_name})"
class EagerExpr(
DepthTrackingExpr[EagerDataFrameT, EagerSeriesT],
Protocol[EagerDataFrameT, EagerSeriesT],
):
_call: EvalSeries[EagerDataFrameT, EagerSeriesT]
_scalar_kwargs: ScalarKwargs
def __init__(
self,
call: EvalSeries[EagerDataFrameT, EagerSeriesT],
*,
depth: int,
function_name: str,
evaluate_output_names: EvalNames[EagerDataFrameT],
alias_output_names: AliasNames | None,
implementation: Implementation,
version: Version,
scalar_kwargs: ScalarKwargs | None = None,
) -> None: ...
def __call__(self, df: EagerDataFrameT) -> Sequence[EagerSeriesT]:
return self._call(df)
def __narwhals_namespace__(
self,
) -> EagerNamespace[EagerDataFrameT, EagerSeriesT, Self, Any, Any]: ...
def __narwhals_expr__(self) -> None: ...
@classmethod
def _from_callable(
cls,
func: EvalSeries[EagerDataFrameT, EagerSeriesT],
*,
depth: int,
function_name: str,
evaluate_output_names: EvalNames[EagerDataFrameT],
alias_output_names: AliasNames | None,
context: _LimitedContext,
scalar_kwargs: ScalarKwargs | None = None,
) -> Self:
return cls(
func,
depth=depth,
function_name=function_name,
evaluate_output_names=evaluate_output_names,
alias_output_names=alias_output_names,
implementation=context._implementation,
version=context._version,
scalar_kwargs=scalar_kwargs,
)
@classmethod
def _from_series(cls, series: EagerSeriesT) -> Self:
return cls(
lambda _df: [series],
depth=0,
function_name="series",
evaluate_output_names=lambda _df: [series.name],
alias_output_names=None,
implementation=series._implementation,
version=series._version,
)
def _with_alias_output_names(self, alias_name: AliasName | None, /) -> Self:
current_alias_output_names = self._alias_output_names
alias_output_names: AliasNames | None = (
None
if alias_name is None
else (
lambda output_names: [
alias_name(x) for x in current_alias_output_names(output_names)
]
)
if current_alias_output_names is not None
else (lambda output_names: [alias_name(x) for x in output_names])
)
def func(df: EagerDataFrameT) -> list[EagerSeriesT]:
if alias_output_names:
return [
series.alias(name)
for series, name in zip(
self(df), alias_output_names(self._evaluate_output_names(df))
)
]
return [
series.alias(name)
for series, name in zip(self(df), self._evaluate_output_names(df))
]
return self.__class__(
func,
depth=self._depth,
function_name=self._function_name,
evaluate_output_names=self._evaluate_output_names,
alias_output_names=alias_output_names,
implementation=self._implementation,
version=self._version,
scalar_kwargs=self._scalar_kwargs,
)
def _reuse_series(
self,
method_name: str,
*,
returns_scalar: bool = False,
scalar_kwargs: ScalarKwargs | None = None,
**expressifiable_args: Any,
) -> Self:
"""Reuse Series implementation for expression.
If Series.foo is already defined, and we'd like Expr.foo to be the same, we can
leverage this method to do that for us.
Arguments:
method_name: name of method.
returns_scalar: whether the Series version returns a scalar. In this case,
the expression version should return a 1-row Series.
scalar_kwargs: non-expressifiable args which we may need to reuse in `agg` or `over`,
such as `ddof` for `std` and `var`.
expressifiable_args: keyword arguments to pass to function, which may
be expressifiable (e.g. `nw.col('a').is_between(3, nw.col('b')))`).
"""
func = partial(
self._reuse_series_inner,
method_name=method_name,
returns_scalar=returns_scalar,
scalar_kwargs=scalar_kwargs or {},
expressifiable_args=expressifiable_args,
)
return self._from_callable(
func,
depth=self._depth + 1,
function_name=f"{self._function_name}->{method_name}",
evaluate_output_names=self._evaluate_output_names,
alias_output_names=self._alias_output_names,
scalar_kwargs=scalar_kwargs,
context=self,
)
# For PyArrow.Series, we return Python Scalars (like Polars does) instead of PyArrow Scalars.
# However, when working with expressions, we keep everything PyArrow-native.
def _reuse_series_extra_kwargs(
self, *, returns_scalar: bool = False
) -> dict[str, Any]:
return {}
@classmethod
def _is_expr(cls, obj: Self | Any) -> TypeIs[Self]:
return hasattr(obj, "__narwhals_expr__")
def _reuse_series_inner(
self,
df: EagerDataFrameT,
*,
method_name: str,
returns_scalar: bool,
scalar_kwargs: ScalarKwargs,
expressifiable_args: dict[str, Any],
) -> Sequence[EagerSeriesT]:
kwargs = {
**scalar_kwargs,
**{
name: df._evaluate_expr(value) if self._is_expr(value) else value
for name, value in expressifiable_args.items()
},
}
method = methodcaller(
method_name,
**self._reuse_series_extra_kwargs(returns_scalar=returns_scalar),
**kwargs,
)
out: Sequence[EagerSeriesT] = [
series._from_scalar(method(series)) if returns_scalar else method(series)
for series in self(df)
]
aliases = self._evaluate_aliases(df)
if [s.name for s in out] != list(aliases): # pragma: no cover
msg = (
f"Safety assertion failed, please report a bug to https://github.com/narwhals-dev/narwhals/issues\n"
f"Expression aliases: {aliases}\n"
f"Series names: {[s.name for s in out]}"
)
raise AssertionError(msg)
return out
def _reuse_series_namespace(
self,
series_namespace: Literal["cat", "dt", "list", "name", "str", "struct"],
method_name: str,
**expressifiable_args: Any,
) -> Self:
"""Reuse Series implementation for expression.
Just like `_reuse_series`, but for e.g. `Expr.dt.foo` instead
of `Expr.foo`.
Arguments:
series_namespace: The Series namespace.
method_name: name of method, within `series_namespace`.
expressifiable_args: keyword arguments to pass to function, which may
be expressifiable (e.g. `nw.col('a').str.replace('abc', nw.col('b')))`).
"""
def inner(df: EagerDataFrameT) -> list[EagerSeriesT]:
kwargs = {
name: df._evaluate_expr(value) if self._is_expr(value) else value
for name, value in expressifiable_args.items()
}
return [
getattr(getattr(series, series_namespace), method_name)(**kwargs)
for series in self(df)
]
return self._from_callable(
inner,
depth=self._depth + 1,
function_name=f"{self._function_name}->{series_namespace}.{method_name}",
evaluate_output_names=self._evaluate_output_names,
alias_output_names=self._alias_output_names,
scalar_kwargs=self._scalar_kwargs,
context=self,
)
def broadcast(self, kind: Literal[ExprKind.AGGREGATION, ExprKind.LITERAL]) -> Self:
# Mark the resulting Series with `_broadcast = True`.
# Then, when extracting native objects, `extract_native` will
# know what to do.
def func(df: EagerDataFrameT) -> list[EagerSeriesT]:
results = []
for result in self(df):
result._broadcast = True
results.append(result)
return results
return type(self)(
func,
depth=self._depth,
function_name=self._function_name,
evaluate_output_names=self._evaluate_output_names,
alias_output_names=self._alias_output_names,
implementation=self._implementation,
version=self._version,
scalar_kwargs=self._scalar_kwargs,
)
def cast(self, dtype: IntoDType) -> Self:
return self._reuse_series("cast", dtype=dtype)
def __eq__(self, other: Self | Any) -> Self: # type: ignore[override]
return self._reuse_series("__eq__", other=other)
def __ne__(self, other: Self | Any) -> Self: # type: ignore[override]
return self._reuse_series("__ne__", other=other)
def __ge__(self, other: Self | Any) -> Self:
return self._reuse_series("__ge__", other=other)
def __gt__(self, other: Self | Any) -> Self:
return self._reuse_series("__gt__", other=other)
def __le__(self, other: Self | Any) -> Self:
return self._reuse_series("__le__", other=other)
def __lt__(self, other: Self | Any) -> Self:
return self._reuse_series("__lt__", other=other)
def __and__(self, other: Self | bool | Any) -> Self:
return self._reuse_series("__and__", other=other)
def __or__(self, other: Self | bool | Any) -> Self:
return self._reuse_series("__or__", other=other)
def __add__(self, other: Self | Any) -> Self:
return self._reuse_series("__add__", other=other)
def __sub__(self, other: Self | Any) -> Self:
return self._reuse_series("__sub__", other=other)
def __rsub__(self, other: Self | Any) -> Self:
return self.alias("literal")._reuse_series("__rsub__", other=other)
def __mul__(self, other: Self | Any) -> Self:
return self._reuse_series("__mul__", other=other)
def __truediv__(self, other: Self | Any) -> Self:
return self._reuse_series("__truediv__", other=other)
def __rtruediv__(self, other: Self | Any) -> Self:
return self.alias("literal")._reuse_series("__rtruediv__", other=other)
def __floordiv__(self, other: Self | Any) -> Self:
return self._reuse_series("__floordiv__", other=other)
def __rfloordiv__(self, other: Self | Any) -> Self:
return self.alias("literal")._reuse_series("__rfloordiv__", other=other)
def __pow__(self, other: Self | Any) -> Self:
return self._reuse_series("__pow__", other=other)
def __rpow__(self, other: Self | Any) -> Self:
return self.alias("literal")._reuse_series("__rpow__", other=other)
def __mod__(self, other: Self | Any) -> Self:
return self._reuse_series("__mod__", other=other)
def __rmod__(self, other: Self | Any) -> Self:
return self.alias("literal")._reuse_series("__rmod__", other=other)
# Unary
def __invert__(self) -> Self:
return self._reuse_series("__invert__")
# Reductions
def null_count(self) -> Self:
return self._reuse_series("null_count", returns_scalar=True)
def n_unique(self) -> Self:
return self._reuse_series("n_unique", returns_scalar=True)
def sum(self) -> Self:
return self._reuse_series("sum", returns_scalar=True)
def count(self) -> Self:
return self._reuse_series("count", returns_scalar=True)
def mean(self) -> Self:
return self._reuse_series("mean", returns_scalar=True)
def median(self) -> Self:
return self._reuse_series("median", returns_scalar=True)
def std(self, *, ddof: int) -> Self:
return self._reuse_series(
"std", returns_scalar=True, scalar_kwargs={"ddof": ddof}
)
def var(self, *, ddof: int) -> Self:
return self._reuse_series(
"var", returns_scalar=True, scalar_kwargs={"ddof": ddof}
)
def skew(self) -> Self:
return self._reuse_series("skew", returns_scalar=True)
def kurtosis(self) -> Self:
return self._reuse_series("kurtosis", returns_scalar=True)
def any(self) -> Self:
return self._reuse_series("any", returns_scalar=True)
def all(self) -> Self:
return self._reuse_series("all", returns_scalar=True)
def max(self) -> Self:
return self._reuse_series("max", returns_scalar=True)
def min(self) -> Self:
return self._reuse_series("min", returns_scalar=True)
def arg_min(self) -> Self:
return self._reuse_series("arg_min", returns_scalar=True)
def arg_max(self) -> Self:
return self._reuse_series("arg_max", returns_scalar=True)
# Other
def clip(
self,
lower_bound: Self | NumericLiteral | TemporalLiteral | None,
upper_bound: Self | NumericLiteral | TemporalLiteral | None,
) -> Self:
return self._reuse_series(
"clip", lower_bound=lower_bound, upper_bound=upper_bound
)
def is_null(self) -> Self:
return self._reuse_series("is_null")
def is_nan(self) -> Self:
return self._reuse_series("is_nan")
def fill_null(
self,
value: Self | NonNestedLiteral,
strategy: FillNullStrategy | None,
limit: int | None,
) -> Self:
return self._reuse_series(
"fill_null", value=value, scalar_kwargs={"strategy": strategy, "limit": limit}
)
def is_in(self, other: Any) -> Self:
return self._reuse_series("is_in", other=other)
def arg_true(self) -> Self:
return self._reuse_series("arg_true")
def filter(self, *predicates: Self) -> Self:
plx = self.__narwhals_namespace__()
predicate = plx.all_horizontal(*predicates, ignore_nulls=False)
return self._reuse_series("filter", predicate=predicate)
def drop_nulls(self) -> Self:
return self._reuse_series("drop_nulls")
def replace_strict(
self,
old: Sequence[Any] | Mapping[Any, Any],
new: Sequence[Any],
*,
return_dtype: IntoDType | None,
) -> Self:
return self._reuse_series(
"replace_strict", old=old, new=new, return_dtype=return_dtype
)
def sort(self, *, descending: bool, nulls_last: bool) -> Self:
return self._reuse_series("sort", descending=descending, nulls_last=nulls_last)
def abs(self) -> Self:
return self._reuse_series("abs")
def unique(self) -> Self:
return self._reuse_series("unique", maintain_order=False)
def diff(self) -> Self:
return self._reuse_series("diff")
def sample(
self,
n: int | None,
*,
fraction: float | None,
with_replacement: bool,
seed: int | None,
) -> Self:
return self._reuse_series(
"sample", n=n, fraction=fraction, with_replacement=with_replacement, seed=seed
)
def alias(self, name: str) -> Self:
def alias_output_names(names: Sequence[str]) -> Sequence[str]:
if len(names) != 1:
msg = f"Expected function with single output, found output names: {names}"
raise ValueError(msg)
return [name]
# Define this one manually, so that we can
# override `output_names` and not increase depth
return type(self)(
lambda df: [series.alias(name) for series in self(df)],
depth=self._depth,
function_name=self._function_name,
evaluate_output_names=self._evaluate_output_names,
alias_output_names=alias_output_names,
implementation=self._implementation,
version=self._version,
scalar_kwargs=self._scalar_kwargs,
)
def is_unique(self) -> Self:
return self._reuse_series("is_unique")
def is_first_distinct(self) -> Self:
return self._reuse_series("is_first_distinct")
def is_last_distinct(self) -> Self:
return self._reuse_series("is_last_distinct")
def quantile(
self, quantile: float, interpolation: RollingInterpolationMethod
) -> Self:
return self._reuse_series(
"quantile",
returns_scalar=True,
scalar_kwargs={"quantile": quantile, "interpolation": interpolation},
)
def head(self, n: int) -> Self:
return self._reuse_series("head", scalar_kwargs={"n": n})
def tail(self, n: int) -> Self:
return self._reuse_series("tail", scalar_kwargs={"n": n})
def round(self, decimals: int) -> Self:
return self._reuse_series("round", decimals=decimals)
def len(self) -> Self:
return self._reuse_series("len", returns_scalar=True)
def gather_every(self, n: int, offset: int) -> Self:
return self._reuse_series("gather_every", n=n, offset=offset)
def mode(self) -> Self:
return self._reuse_series("mode")
def is_finite(self) -> Self:
return self._reuse_series("is_finite")
def rolling_mean(self, window_size: int, *, min_samples: int, center: bool) -> Self:
return self._reuse_series(
"rolling_mean",
scalar_kwargs={
"window_size": window_size,
"min_samples": min_samples,
"center": center,
},
)
def rolling_std(
self, window_size: int, *, min_samples: int, center: bool, ddof: int
) -> Self:
return self._reuse_series(
"rolling_std",
scalar_kwargs={
"window_size": window_size,
"min_samples": min_samples,
"center": center,
"ddof": ddof,
},
)
def rolling_sum(self, window_size: int, *, min_samples: int, center: bool) -> Self:
return self._reuse_series(
"rolling_sum",
scalar_kwargs={
"window_size": window_size,
"min_samples": min_samples,
"center": center,
},
)
def rolling_var(
self, window_size: int, *, min_samples: int, center: bool, ddof: int
) -> Self:
return self._reuse_series(
"rolling_var",
scalar_kwargs={
"window_size": window_size,
"min_samples": min_samples,
"center": center,
"ddof": ddof,
},
)
def map_batches(
self, function: Callable[[Any], Any], return_dtype: IntoDType | None
) -> Self:
def func(df: EagerDataFrameT) -> Sequence[EagerSeriesT]:
input_series_list = self(df)
output_names = [input_series.name for input_series in input_series_list]
result = [function(series) for series in input_series_list]
if is_numpy_array(result[0]) or (
(np := get_numpy()) is not None and np.isscalar(result[0])
):
from_numpy = partial(
self.__narwhals_namespace__()._series.from_numpy, context=self
)
result = [
from_numpy(array).alias(output_name)
for array, output_name in zip(result, output_names)
]
if return_dtype is not None:
result = [series.cast(return_dtype) for series in result]
return result
return self._from_callable(
func,
depth=self._depth + 1,
function_name=self._function_name + "->map_batches",
evaluate_output_names=self._evaluate_output_names,
alias_output_names=self._alias_output_names,
context=self,
)
def shift(self, n: int) -> Self:
return self._reuse_series("shift", scalar_kwargs={"n": n})
def cum_sum(self, *, reverse: bool) -> Self:
return self._reuse_series("cum_sum", scalar_kwargs={"reverse": reverse})
def cum_count(self, *, reverse: bool) -> Self:
return self._reuse_series("cum_count", scalar_kwargs={"reverse": reverse})
def cum_min(self, *, reverse: bool) -> Self:
return self._reuse_series("cum_min", scalar_kwargs={"reverse": reverse})
def cum_max(self, *, reverse: bool) -> Self:
return self._reuse_series("cum_max", scalar_kwargs={"reverse": reverse})
def cum_prod(self, *, reverse: bool) -> Self:
return self._reuse_series("cum_prod", scalar_kwargs={"reverse": reverse})
def rank(self, method: RankMethod, *, descending: bool) -> Self:
return self._reuse_series(
"rank", scalar_kwargs={"method": method, "descending": descending}
)
def log(self, base: float) -> Self:
return self._reuse_series("log", base=base)
def exp(self) -> Self:
return self._reuse_series("exp")
def sqrt(self) -> Self:
return self._reuse_series("sqrt")
@property
def cat(self) -> EagerExprCatNamespace[Self]:
return EagerExprCatNamespace(self)
@property
def dt(self) -> EagerExprDateTimeNamespace[Self]:
return EagerExprDateTimeNamespace(self)
@property
def list(self) -> EagerExprListNamespace[Self]:
return EagerExprListNamespace(self)
@property
def name(self) -> EagerExprNameNamespace[Self]:
return EagerExprNameNamespace(self)
@property
def str(self) -> EagerExprStringNamespace[Self]:
return EagerExprStringNamespace(self)
@property
def struct(self) -> EagerExprStructNamespace[Self]:
return EagerExprStructNamespace(self)
# mypy thinks `NativeExprT` should be covariant, pyright thinks it should be invariant
class LazyExpr( # type: ignore[misc]
CompliantExpr[CompliantLazyFrameT, NativeExprT],
Protocol[CompliantLazyFrameT, NativeExprT],
):
def _with_alias_output_names(self, func: AliasNames | None, /) -> Self: ...
def alias(self, name: str) -> Self:
def fn(names: Sequence[str]) -> Sequence[str]:
if len(names) != 1:
msg = f"Expected function with single output, found output names: {names}"
raise ValueError(msg)
return [name]
return self._with_alias_output_names(fn)
@property
def name(self) -> LazyExprNameNamespace[Self]:
return LazyExprNameNamespace(self)
class _ExprNamespace( # type: ignore[misc]
_StoresCompliant[CompliantExprT_co], Protocol[CompliantExprT_co]
):
_compliant_expr: CompliantExprT_co
@property
def compliant(self) -> CompliantExprT_co:
return self._compliant_expr
class EagerExprNamespace(_ExprNamespace[EagerExprT], Generic[EagerExprT]):
def __init__(self, expr: EagerExprT, /) -> None:
self._compliant_expr = expr
class LazyExprNamespace(_ExprNamespace[LazyExprT], Generic[LazyExprT]):
def __init__(self, expr: LazyExprT, /) -> None:
self._compliant_expr = expr
class EagerExprCatNamespace(
EagerExprNamespace[EagerExprT], CatNamespace[EagerExprT], Generic[EagerExprT]
):
def get_categories(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("cat", "get_categories")
class EagerExprDateTimeNamespace(
EagerExprNamespace[EagerExprT], DateTimeNamespace[EagerExprT], Generic[EagerExprT]
):
def to_string(self, format: str) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "to_string", format=format)
def replace_time_zone(self, time_zone: str | None) -> EagerExprT:
return self.compliant._reuse_series_namespace(
"dt", "replace_time_zone", time_zone=time_zone
)
def convert_time_zone(self, time_zone: str) -> EagerExprT:
return self.compliant._reuse_series_namespace(
"dt", "convert_time_zone", time_zone=time_zone
)
def timestamp(self, time_unit: TimeUnit) -> EagerExprT:
return self.compliant._reuse_series_namespace(
"dt", "timestamp", time_unit=time_unit
)
def date(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "date")
def year(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "year")
def month(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "month")
def day(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "day")
def hour(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "hour")
def minute(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "minute")
def second(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "second")
def millisecond(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "millisecond")
def microsecond(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "microsecond")
def nanosecond(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "nanosecond")
def ordinal_day(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "ordinal_day")
def weekday(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "weekday")
def total_minutes(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "total_minutes")
def total_seconds(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "total_seconds")
def total_milliseconds(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "total_milliseconds")
def total_microseconds(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "total_microseconds")
def total_nanoseconds(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "total_nanoseconds")
def truncate(self, every: str) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "truncate", every=every)
def offset_by(self, by: str) -> EagerExprT:
return self.compliant._reuse_series_namespace("dt", "offset_by", by=by)
class EagerExprListNamespace(
EagerExprNamespace[EagerExprT], ListNamespace[EagerExprT], Generic[EagerExprT]
):
def len(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("list", "len")
class CompliantExprNameNamespace( # type: ignore[misc]
_ExprNamespace[CompliantExprT_co],
NameNamespace[CompliantExprT_co],
Protocol[CompliantExprT_co],
):
def keep(self) -> CompliantExprT_co:
return self._from_callable(None)
def map(self, function: AliasName) -> CompliantExprT_co:
return self._from_callable(function)
def prefix(self, prefix: str) -> CompliantExprT_co:
return self._from_callable(lambda name: f"{prefix}{name}")
def suffix(self, suffix: str) -> CompliantExprT_co:
return self._from_callable(lambda name: f"{name}{suffix}")
def to_lowercase(self) -> CompliantExprT_co:
return self._from_callable(str.lower)
def to_uppercase(self) -> CompliantExprT_co:
return self._from_callable(str.upper)
@staticmethod
def _alias_output_names(func: AliasName, /) -> AliasNames:
def fn(output_names: Sequence[str], /) -> Sequence[str]:
return [func(name) for name in output_names]
return fn
def _from_callable(self, func: AliasName | None, /) -> CompliantExprT_co: ...
class EagerExprNameNamespace(
EagerExprNamespace[EagerExprT],
CompliantExprNameNamespace[EagerExprT],
Generic[EagerExprT],
):
def _from_callable(self, func: AliasName | None) -> EagerExprT:
expr = self.compliant
return expr._with_alias_output_names(func)
class LazyExprNameNamespace(
LazyExprNamespace[LazyExprT],
CompliantExprNameNamespace[LazyExprT],
Generic[LazyExprT],
):
def _from_callable(self, func: AliasName | None) -> LazyExprT:
expr = self.compliant
output_names = self._alias_output_names(func) if func else None
return expr._with_alias_output_names(output_names)
class EagerExprStringNamespace(
EagerExprNamespace[EagerExprT], StringNamespace[EagerExprT], Generic[EagerExprT]
):
def len_chars(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("str", "len_chars")
def replace(self, pattern: str, value: str, *, literal: bool, n: int) -> EagerExprT:
return self.compliant._reuse_series_namespace(
"str", "replace", pattern=pattern, value=value, literal=literal, n=n
)
def replace_all(self, pattern: str, value: str, *, literal: bool) -> EagerExprT:
return self.compliant._reuse_series_namespace(
"str", "replace_all", pattern=pattern, value=value, literal=literal
)
def strip_chars(self, characters: str | None) -> EagerExprT:
return self.compliant._reuse_series_namespace(
"str", "strip_chars", characters=characters
)
def starts_with(self, prefix: str) -> EagerExprT:
return self.compliant._reuse_series_namespace("str", "starts_with", prefix=prefix)
def ends_with(self, suffix: str) -> EagerExprT:
return self.compliant._reuse_series_namespace("str", "ends_with", suffix=suffix)
def contains(self, pattern: str, *, literal: bool) -> EagerExprT:
return self.compliant._reuse_series_namespace(
"str", "contains", pattern=pattern, literal=literal
)
def slice(self, offset: int, length: int | None) -> EagerExprT:
return self.compliant._reuse_series_namespace(
"str", "slice", offset=offset, length=length
)
def split(self, by: str) -> EagerExprT:
return self.compliant._reuse_series_namespace("str", "split", by=by)
def to_datetime(self, format: str | None) -> EagerExprT:
return self.compliant._reuse_series_namespace("str", "to_datetime", format=format)
def to_date(self, format: str | None) -> EagerExprT:
return self.compliant._reuse_series_namespace("str", "to_date", format=format)
def to_lowercase(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("str", "to_lowercase")
def to_uppercase(self) -> EagerExprT:
return self.compliant._reuse_series_namespace("str", "to_uppercase")
def zfill(self, width: int) -> EagerExprT:
return self.compliant._reuse_series_namespace("str", "zfill", width=width)
class EagerExprStructNamespace(
EagerExprNamespace[EagerExprT], StructNamespace[EagerExprT], Generic[EagerExprT]
):
def field(self, name: str) -> EagerExprT:
return self.compliant._reuse_series_namespace("struct", "field", name=name).alias(
name
)