Add polars accessor

pyproject.toml

@@ -50,7 +50,8 @@ test = [
   "awkward-pandas[complete]",
   "pytest >=6.0",
   "pytest-cov >=3.0.0",
-  "distributed"
+  "distributed",
+  "polars"
 ]
 docs = [
   "sphinx",

src/awkward_pandas/dask_connect.py

@@ -16,9 +16,12 @@ def _(x):
 
 
 try:
-    from dask.dataframe.accessor import Accessor
+    from dask_expr._accessor import Accessor
 except (ImportError, ModuleNotFoundError):
-    Accessor = object
+    try:
+        from dask.dataframe.accessor import Accessor
+    except (ImportError, ModuleNotFoundError):
+        Accessor = object
 
 
 class DaskAwkwardAccessor(Accessor):

src/awkward_pandas/mixin.py

@@ -0,0 +1,117 @@
+import operator
+
+
+def radd(left, right):
+    return right + left
+
+
+def rsub(left, right):
+    return right - left
+
+
+def rmul(left, right):
+    return right * left
+
+
+def rdiv(left, right):
+    return right / left
+
+
+def rtruediv(left, right):
+    return right / left
+
+
+def rfloordiv(left, right):
+    return right // left
+
+
+def rmod(left, right):
+    # check if right is a string as % is the string
+    # formatting operation; this is a TypeError
+    # otherwise perform the op
+    if isinstance(right, str):
+        typ = type(left).__name__
+        raise TypeError(f"{typ} cannot perform the operation mod")
+
+    return right % left
+
+
+def rdivmod(left, right):
+    return divmod(right, left)
+
+
+def rpow(left, right):
+    return right**left
+
+
+def rand_(left, right):
+    return operator.and_(right, left)
+
+
+def ror_(left, right):
+    return operator.or_(right, left)
+
+
+def rxor(left, right):
+    return operator.xor(right, left)
+
+
+class AbstractMethodError(NotImplementedError):
+    pass
+
+
+class ArithmeticMixin:
+    @classmethod
+    def _create_arithmetic_method(cls, op):
+        raise AbstractMethodError(cls)
+
+    @classmethod
+    def _create_comparison_method(cls, op):
+        raise AbstractMethodError(cls)
+
+    @classmethod
+    def _create_logical_method(cls, op):
+        raise AbstractMethodError(cls)
+
+    @classmethod
+    def _add_arithmetic_ops(cls) -> None:
+        setattr(cls, "__add__", cls._create_arithmetic_method(operator.add))
+        setattr(cls, "__radd__", cls._create_arithmetic_method(radd))
+        setattr(cls, "__sub__", cls._create_arithmetic_method(operator.sub))
+        setattr(cls, "__rsub__", cls._create_arithmetic_method(rsub))
+        setattr(cls, "__mul__", cls._create_arithmetic_method(operator.mul))
+        setattr(cls, "__rmul__", cls._create_arithmetic_method(rmul))
+        setattr(cls, "__pow__", cls._create_arithmetic_method(operator.pow))
+        setattr(cls, "__rpow__", cls._create_arithmetic_method(rpow))
+        setattr(cls, "__mod__", cls._create_arithmetic_method(operator.mod))
+        setattr(cls, "__rmod__", cls._create_arithmetic_method(rmod))
+        setattr(cls, "__floordiv__", cls._create_arithmetic_method(operator.floordiv))
+        setattr(cls, "__rfloordiv__", cls._create_arithmetic_method(rfloordiv))
+        setattr(cls, "__truediv__", cls._create_arithmetic_method(operator.truediv))
+        setattr(cls, "__rtruediv__", cls._create_arithmetic_method(rtruediv))
+        setattr(cls, "__divmod__", cls._create_arithmetic_method(divmod))
+        setattr(cls, "__rdivmod__", cls._create_arithmetic_method(rdivmod))
+
+    @classmethod
+    def _add_comparison_ops(cls) -> None:
+        setattr(cls, "__eq__", cls._create_comparison_method(operator.eq))
+        setattr(cls, "__ne__", cls._create_comparison_method(operator.ne))
+        setattr(cls, "__lt__", cls._create_comparison_method(operator.lt))
+        setattr(cls, "__gt__", cls._create_comparison_method(operator.gt))
+        setattr(cls, "__le__", cls._create_comparison_method(operator.le))
+        setattr(cls, "__ge__", cls._create_comparison_method(operator.ge))
+
+    @classmethod
+    def _add_logical_ops(cls) -> None:
+        setattr(cls, "__and__", cls._create_logical_method(operator.and_))
+        setattr(cls, "__rand__", cls._create_logical_method(rand_))
+        setattr(cls, "__or__", cls._create_logical_method(operator.or_))
+        setattr(cls, "__ror__", cls._create_logical_method(ror_))
+        setattr(cls, "__xor__", cls._create_logical_method(operator.xor))
+        setattr(cls, "__rxor__", cls._create_logical_method(rxor))
+
+    @classmethod
+    def _add_all(cls):
+        cls._add_logical_ops()
+        cls._add_arithmetic_ops()
+        cls._add_comparison_ops()

src/awkward_pandas/polars.py

@@ -0,0 +1,91 @@
+import functools
+from typing import Callable, Iterable, Union
+
+import awkward as ak
+import polars as pl
+
+from awkward_pandas.mixin import ArithmeticMixin
+
+
+@pl.api.register_series_namespace("ak")
+@pl.api.register_dataframe_namespace("ak")
+class AwkwardOperations(ArithmeticMixin):
+    def __init__(self, df: pl.DataFrame):
+        self._df = df
+
+    def __array_function__(self, *args, **kwargs):
+        return self.array.__array_function__(*args, **kwargs)
+
+    def __array_ufunc__(self, *args, **kwargs):
+        if args[1] == "__call__":
+            return args[0](self.array, *args[3:], **kwargs)
+        raise NotImplementedError
+
+    def __dir__(self) -> Iterable[str]:
+        return [
+            _
+            for _ in (dir(ak))
+            if not _.startswith(("_", "ak_")) and not _[0].isupper()
+        ] + ["apply", "array"]
+
+    def apply(self, fn: Callable) -> pl.DataFrame:
+        """Perform function on all the values of the series"""
+        out = fn(self.array)
+        return ak_to_polars(out)
+
+    def __getitem__(self, item):
+        # scalars?
+        out = self.array.__getitem__(item)
+        result = ak_to_polars(out)
+        return result
+
+    @property
+    def array(self):
+        return ak.from_arrow(self._df.to_arrow())
+
+    def __getattr__(self, item):
+        if item not in dir(self):
+            raise AttributeError
+        func = getattr(ak, item, None)
+
+        if func:
+
+            @functools.wraps(func)
+            def f(*others, **kwargs):
+                others = [
+                    other.ak.array
+                    if isinstance(other, (pl.DataFrame, pl.Series))
+                    else other
+                    for other in others
+                ]
+                kwargs = {
+                    k: v.ak.array if isinstance(v, (pl.DataFrame, pl.Series)) else v
+                    for k, v in kwargs.items()
+                }
+
+                ak_arr = func(self.array, *others, **kwargs)
+                if isinstance(ak_arr, ak.Array):
+                    return ak_to_polars(ak_arr)
+                return ak_arr
+
+        else:
+            raise AttributeError(item)
+        return f
+
+    @classmethod
+    def _create_op(cls, op):
+        def run(self, *args, **kwargs):
+            return ak_to_polars(op(self.array, *args, **kwargs))
+
+        return run
+
+    _create_arithmetic_method = _create_op
+    _create_comparison_method = _create_op
+    _create_logical_method = _create_op
+
+
+AwkwardOperations._add_all()
+
+
+def ak_to_polars(arr: ak.Array) -> Union[pl.DataFrame, pl.Series]:
+    return pl.from_arrow(ak.to_arrow(arr, extensionarray=False))

tests/test_polars.py

@@ -0,0 +1,33 @@
+import numpy as np
+import pytest
+
+import awkward_pandas.polars  # noqa: F401
+
+pl = pytest.importorskip("polars")
+
+
+def test_simple():
+    s = pl.Series([[1, 2, 3], [], [4, 5]])
+    s2 = s.ak[:, -1:]
+    assert s2.to_list() == [[3], [], [5]]
+
+
+def test_apply():
+    s = pl.Series([[1, 2, 3], [], [4, 5]])
+    s2 = s.ak.apply(np.negative)
+    assert s2.to_list() == [[-1, -2, -3], [], [-4, -5]]
+
+
+def test_operator():
+    s = pl.Series([[1, 2, 3], [], [4, 5]])
+    s2 = s.ak + 1
+    assert s2.to_list() == [[2, 3, 4], [], [5, 6]]
+
+
+def test_ufunc():
+    s = pl.Series([[1, 2, 3], [], [4, 5]])
+    s2 = np.negative(s.ak)
+    assert s2.to_list() == [[-1, -2, -3], [], [-4, -5]]
+
+    s2 = np.add(s.ak, 1)
+    assert s2.to_list() == [[2, 3, 4], [], [5, 6]]