Misc Column cleanups (#15682)

* Some typing
* Moved a single use helper function inline
* Some dtype checking simplification

Authors:
  - Matthew Roeschke (https://github.com/mroeschke)
  - GALI PREM SAGAR (https://github.com/galipremsagar)

Approvers:
  - GALI PREM SAGAR (https://github.com/galipremsagar)

URL: #15682

python/cudf/cudf/core/column/column.py

@@ -56,7 +56,6 @@
     infer_dtype,
     is_bool_dtype,
     is_dtype_equal,
-    is_integer_dtype,
     is_scalar,
     is_string_dtype,
 )
@@ -606,7 +605,8 @@ def _scatter_by_slice(
         start, stop, step = key.indices(len(self))
         if start >= stop:
             return None
-        num_keys = len(range(start, stop, step))
+        rng = range(start, stop, step)
+        num_keys = len(rng)
 
         self._check_scatter_key_length(num_keys, value)
 
@@ -625,7 +625,7 @@ def _scatter_by_slice(
 
         # step != 1, create a scatter map with arange
         scatter_map = as_column(
-            range(start, stop, step),
+            rng,
             dtype=cudf.dtype(np.int32),
         )
 
@@ -672,18 +672,16 @@ def _scatter_by_column(
 
     def _check_scatter_key_length(
         self, num_keys: int, value: Union[cudf.core.scalar.Scalar, ColumnBase]
-    ):
+    ) -> None:
         """`num_keys` is the number of keys to scatter. Should equal to the
         number of rows in ``value`` if ``value`` is a column.
         """
-        if isinstance(value, ColumnBase):
-            if len(value) != num_keys:
-                msg = (
-                    f"Size mismatch: cannot set value "
-                    f"of size {len(value)} to indexing result of size "
-                    f"{num_keys}"
-                )
-                raise ValueError(msg)
+        if isinstance(value, ColumnBase) and len(value) != num_keys:
+            raise ValueError(
+                f"Size mismatch: cannot set value "
+                f"of size {len(value)} to indexing result of size "
+                f"{num_keys}"
+            )
 
     def fillna(
         self,
@@ -820,7 +818,7 @@ def take(
 
         # TODO: For performance, the check and conversion of gather map should
         # be done by the caller. This check will be removed in future release.
-        if not is_integer_dtype(indices.dtype):
+        if indices.dtype.kind not in {"u", "i"}:
             indices = indices.astype(libcudf.types.size_type_dtype)
         if not libcudf.copying._gather_map_is_valid(
             indices, len(self), check_bounds, nullify

python/cudf/cudf/core/column/numerical_base.py

@@ -1,4 +1,4 @@
-# Copyright (c) 2018-2023, NVIDIA CORPORATION.
+# Copyright (c) 2018-2024, NVIDIA CORPORATION.
 """Define an interface for columns that can perform numerical operations."""
 
 from __future__ import annotations
@@ -112,7 +112,13 @@ def quantile(
                 ),
             )
         else:
-            result = self._numeric_quantile(q, interpolation, exact)
+            # get sorted indices and exclude nulls
+            indices = libcudf.sort.order_by(
+                [self], [True], "first", stable=True
+            ).slice(self.null_count, len(self))
+            result = libcudf.quantiles.quantile(
+                self, q, interpolation, indices, exact
+            )
         if return_scalar:
             scalar_result = result.element_indexing(0)
             if interpolation in {"lower", "higher", "nearest"}:
@@ -178,18 +184,6 @@ def median(self, skipna: Optional[bool] = None) -> NumericalBaseColumn:
             return_scalar=True,
         )
 
-    def _numeric_quantile(
-        self, q: np.ndarray, interpolation: str, exact: bool
-    ) -> NumericalBaseColumn:
-        # get sorted indices and exclude nulls
-        indices = libcudf.sort.order_by(
-            [self], [True], "first", stable=True
-        ).slice(self.null_count, len(self))
-
-        return libcudf.quantiles.quantile(
-            self, q, interpolation, indices, exact
-        )
-
     def cov(self, other: NumericalBaseColumn) -> float:
         if (
             len(self) == 0