eptm_dashboard/.venv/lib/python3.12/site-packages/narwhals/_ibis/namespace.py

181 lines
6.3 KiB
Python

from __future__ import annotations
import operator
from functools import reduce
from itertools import chain
from typing import TYPE_CHECKING, Any
import ibis
import ibis.expr.types as ir
from narwhals._compliant.namespace import AlignDiagonal
from narwhals._expression_parsing import (
combine_alias_output_names,
combine_evaluate_output_names,
evaluate_output_names_and_aliases,
)
from narwhals._ibis.dataframe import IbisLazyFrame
from narwhals._ibis.expr import IbisExpr
from narwhals._ibis.selectors import IbisSelectorNamespace
from narwhals._ibis.utils import function, lit, narwhals_to_native_dtype
from narwhals._sql.namespace import SQLNamespace
from narwhals._utils import Implementation, zip_strict
if TYPE_CHECKING:
from collections.abc import Iterable, Mapping, Sequence
from narwhals._utils import Version
from narwhals.typing import ConcatMethod, CorrelationMethod, IntoDType, PythonLiteral
class IbisNamespace(
SQLNamespace[IbisLazyFrame, IbisExpr, "ir.Table", "ir.Value"],
AlignDiagonal[IbisLazyFrame, IbisExpr],
):
_implementation: Implementation = Implementation.IBIS
def __init__(self, *, version: Version) -> None:
self._version = version
@property
def selectors(self) -> IbisSelectorNamespace:
return IbisSelectorNamespace.from_namespace(self)
@property
def _expr(self) -> type[IbisExpr]:
return IbisExpr
@property
def _lazyframe(self) -> type[IbisLazyFrame]:
return IbisLazyFrame
def _function(self, name: str, *args: ir.Value | PythonLiteral) -> ir.Value:
return function(name, *args)
def _lit(self, value: Any) -> ir.Value:
return lit(value)
def _when(
self, condition: ir.Value, value: ir.Value, otherwise: ir.Expr | None = None
) -> ir.Value:
if otherwise is None:
return ibis.cases((condition, value))
return ibis.cases((condition, value), else_=otherwise) # pragma: no cover
def _coalesce(self, *exprs: ir.Value) -> ir.Value:
return ibis.coalesce(*exprs)
def concat(
self, items: Iterable[IbisLazyFrame], *, how: ConcatMethod
) -> IbisLazyFrame:
frames: Sequence[IbisLazyFrame] = tuple(items)
if how == "diagonal":
frames = self.align_diagonal(frames)
try:
result = ibis.union(*(lf.native for lf in frames))
except ibis.IbisError:
first = frames[0].schema
if not all(x.schema == first for x in frames[1:]):
msg = "inputs should all have the same schema"
raise TypeError(msg) from None
raise
return frames[0]._with_native(result)
def concat_str(
self, *exprs: IbisExpr, separator: str, ignore_nulls: bool
) -> IbisExpr:
def func(df: IbisLazyFrame) -> list[ir.Value]:
cols = chain.from_iterable(expr(df) for expr in exprs)
cols_casted = [s.cast("string") for s in cols]
if ignore_nulls:
result = lit(separator).join(cols_casted)
else:
result = reduce(
lambda acc, col: acc.concat(separator, col),
cols_casted[1:],
cols_casted[0],
)
return [result]
return self._expr(
call=func,
evaluate_output_names=combine_evaluate_output_names(*exprs),
alias_output_names=combine_alias_output_names(*exprs),
version=self._version,
)
def mean_horizontal(self, *exprs: IbisExpr) -> IbisExpr:
def func(cols: Iterable[ir.Value]) -> ir.Value:
cols = list(cols)
return reduce(operator.add, (col.fill_null(lit(0)) for col in cols)) / reduce(
operator.add, (col.isnull().ifelse(lit(0), lit(1)) for col in cols)
)
return self._expr._from_elementwise_horizontal_op(func, *exprs)
def lit(self, value: PythonLiteral, dtype: IntoDType | None) -> IbisExpr:
def func(_df: IbisLazyFrame) -> Sequence[ir.Value]:
ibis_dtype = narwhals_to_native_dtype(dtype, self._version) if dtype else None
if not isinstance(value, dict):
return [lit(value, ibis_dtype)]
if value:
return [ibis.struct(value, type=ibis_dtype)]
msg = "Cannot create an empty struct type for Ibis backend"
raise NotImplementedError(msg)
return self._expr(
func,
evaluate_output_names=lambda _df: ["literal"],
alias_output_names=None,
version=self._version,
)
def len(self) -> IbisExpr:
def func(_df: IbisLazyFrame) -> list[ir.Value]:
return [_df.native.count()]
return self._expr(
call=func,
evaluate_output_names=lambda _df: ["len"],
alias_output_names=None,
version=self._version,
)
def corr(self, a: IbisExpr, b: IbisExpr, *, method: CorrelationMethod) -> IbisExpr:
if method != "pearson":
msg = "Only 'pearson' correlation is supported for Ibis."
raise NotImplementedError(msg)
def func(_df: IbisLazyFrame) -> list[ir.Value]:
a_ = _df._evaluate_single_output_expr(a)
b_ = _df._evaluate_single_output_expr(b)
return [a_.corr(b_, how="pop")] # pyright: ignore[reportAttributeAccessIssue]
return self._expr(
func,
evaluate_output_names=combine_evaluate_output_names(a, b),
alias_output_names=combine_alias_output_names(a, b),
version=self._version,
)
def struct(self, *exprs: IbisExpr) -> IbisExpr:
version = self._version
def func(df: IbisLazyFrame) -> list[ir.Value]:
names_to_cols: Mapping[str, ir.Value] = {
alias: native_expr
for expr in exprs
for native_expr, _, alias in zip_strict(
expr(df), *evaluate_output_names_and_aliases(expr, df, [])
)
}
return [ibis.struct(names_to_cols)]
return self._expr(
call=func,
evaluate_output_names=combine_evaluate_output_names(*exprs),
alias_output_names=combine_alias_output_names(*exprs),
version=version,
)