Moves

Author: TomAugspurger

pandas/compat/__init__.py

@@ -451,5 +451,3 @@ def is_platform_mac():
 
 def is_platform_32bit():
     return struct.calcsize("P") * 8 < 64
-
-_default_fill_value = object()

pandas/core/algorithms.py

@@ -30,7 +30,6 @@
     _ensure_platform_int, _ensure_object,
     _ensure_float64, _ensure_uint64,
     _ensure_int64)
-from pandas.compat import _default_fill_value
 from pandas.compat.numpy import _np_version_under1p10
 from pandas.core.dtypes.missing import isna, na_value_for_dtype
 
@@ -1559,81 +1558,6 @@ def take_nd(arr, indexer, axis=0, out=None, fill_value=np.nan, mask_info=None,
 take_1d = take_nd
 
 
-def take_ea(arr, indexer, fill_value=_default_fill_value):
-    """Extension-array compatible take.
-
-    Parameters
-    ----------
-    arr : array-like
-        Must satisify NumPy's take semantics.
-    indexer : sequence of integers
-        Indices to be taken. See Notes for how negative indicies
-        are handled.
-    fill_value : any, optional
-        Fill value to use for NA-indicies. This has a few behaviors.
-
-        * fill_value is not specified : triggers NumPy's semantics
-            where negative values in `indexer` mean slices from the end.
-        * fill_value is NA : Fill positions where `indexer` is ``-1``
-            with ``self.dtype.na_value``. Anything considered NA by
-            :func:`pandas.isna` will result in ``self.dtype.na_value``
-            being used to fill.
-        * fill_value is not NA : Fill positions where `indexer` is ``-1``
-            with `fill_value`.
-
-    Returns
-    -------
-    ExtensionArray
-
-    Raises
-    ------
-    IndexError
-        When the indexer is out of bounds for the array.
-    ValueError
-        When the indexer contains negative values other than ``-1``
-        and `fill_value` is specified.
-
-    Notes
-    -----
-    The meaning of negative values in `indexer` depends on the
-    `fill_value` argument. By default, we follow the behavior
-    :meth:`numpy.take` of where negative indices indicate slices
-    from the end.
-
-    When `fill_value` is specified, we follow pandas semantics of ``-1``
-    indicating a missing value. In this case, positions where `indexer`
-    is ``-1`` will be filled with `fill_value` or the default NA value
-    for this type.
-
-    ExtensionArray.take is called by ``Series.__getitem__``, ``.loc``,
-    ``iloc``, when the indexer is a sequence of values. Additionally,
-    it's called by :meth:`Series.reindex` with a `fill_value`.
-
-    See Also
-    --------
-    numpy.take
-    """
-    indexer = np.asarray(indexer)
-    if fill_value is _default_fill_value:
-        # NumPy style
-        result = arr.take(indexer)
-    else:
-        mask = indexer == -1
-        if (indexer < -1).any():
-            raise ValueError("Invalid value in 'indexer'. All values "
-                             "must be non-negative or -1. When "
-                             "'fill_value' is specified.")
-
-        # take on empty array not handled as desired by numpy
-        # in case of -1 (all missing take)
-        if not len(arr) and mask.all():
-            return arr._from_sequence([fill_value] * len(indexer))
-
-        result = arr.take(indexer)
-        result[mask] = fill_value
-    return result
-
-
 def take_2d_multi(arr, indexer, out=None, fill_value=np.nan, mask_info=None,
                   allow_fill=True):
     """

pandas/core/arrays/base.py

@@ -5,13 +5,70 @@
    This is an experimental API and subject to breaking changes
    without warning.
 """
+import textwrap
+
 import numpy as np
 
 from pandas.errors import AbstractMethodError
-from pandas.compat import _default_fill_value
 from pandas.compat.numpy import function as nv
+from pandas.util._decorators import Appender, Substitution
 
 _not_implemented_message = "{} does not implement {}."
+_default_fill_value = object()
+
+
+_take_docstring = textwrap.dedent("""\
+Take elements from an array.
+
+Parameters
+----------
+%(arr)s\
+indexer : sequence of integers
+    Indices to be taken. See Notes for how negative indicies
+    are handled.
+fill_value : any, optional
+    Fill value to use for NA-indicies. This has a few behaviors.
+
+    * fill_value is not specified : triggers NumPy's semantics
+      where negative values in `indexer` mean slices from the end.
+    * fill_value is NA : Fill positions where `indexer` is ``-1``
+      with ``self.dtype.na_value``. Anything considered NA by
+      :func:`pandas.isna` will result in ``self.dtype.na_value``
+      being used to fill.
+    * fill_value is not NA : Fill positions where `indexer` is ``-1``
+      with `fill_value`.
+
+Returns
+-------
+ExtensionArray
+
+Raises
+------
+IndexError
+    When the indexer is out of bounds for the array.
+ValueError
+    When the indexer contains negative values other than ``-1``
+    and `fill_value` is specified.
+
+Notes
+-----
+The meaning of negative values in `indexer` depends on the
+`fill_value` argument. By default, we follow the behavior
+:meth:`numpy.take` of where negative indices indicate slices
+from the end.
+
+When `fill_value` is specified, we follow pandas semantics of ``-1``
+indicating a missing value. In this case, positions where `indexer`
+is ``-1`` will be filled with `fill_value` or the default NA value
+for this type.
+
+ExtensionArray.take is called by ``Series.__getitem__``, ``.loc``,
+``iloc``, when the indexer is a sequence of values. Additionally,
+it's called by :meth:`Series.reindex` with a `fill_value`.
+
+See Also
+--------
+numpy.take""")
 
 
 class ExtensionArray(object):
@@ -476,60 +533,10 @@ def _values_for_take(self):
         """
         return self.astype(object)
 
+    @Substitution(arr='')
+    @Appender(_take_docstring)
     def take(self, indexer, fill_value=_default_fill_value):
         # type: (Sequence[int], Optional[Any]) -> ExtensionArray
-        """Take elements from an array.
-
-        Parameters
-        ----------
-        indexer : sequence of integers
-            Indices to be taken. See Notes for how negative indicies
-            are handled.
-        fill_value : any, optional
-            Fill value to use for NA-indicies. This has a few behaviors.
-
-            * fill_value is not specified : triggers NumPy's semantics
-              where negative values in `indexer` mean slices from the end.
-            * fill_value is NA : Fill positions where `indexer` is ``-1``
-              with ``self.dtype.na_value``. Anything considered NA by
-              :func:`pandas.isna` will result in ``self.dtype.na_value``
-              being used to fill.
-            * fill_value is not NA : Fill positions where `indexer` is ``-1``
-              with `fill_value`.
-
-        Returns
-        -------
-        ExtensionArray
-
-        Raises
-        ------
-        IndexError
-            When the indexer is out of bounds for the array.
-        ValueError
-            When the indexer contains negative values other than ``-1``
-            and `fill_value` is specified.
-
-        Notes
-        -----
-        The meaning of negative values in `indexer` depends on the
-        `fill_value` argument. By default, we follow the behavior
-        :meth:`numpy.take` of where negative indices indicate slices
-        from the end.
-
-        When `fill_value` is specified, we follow pandas semantics of ``-1``
-        indicating a missing value. In this case, positions where `indexer`
-        is ``-1`` will be filled with `fill_value` or the default NA value
-        for this type.
-
-        ExtensionArray.take is called by ``Series.__getitem__``, ``.loc``,
-        ``iloc``, when the indexer is a sequence of values. Additionally,
-        it's called by :meth:`Series.reindex` with a `fill_value`.
-
-        See Also
-        --------
-        numpy.take
-        """
-        from pandas.core.algorithms import take_ea
         from pandas.core.missing import isna
 
         if isna(fill_value):
@@ -601,3 +608,31 @@ def _ndarray_values(self):
         used for interacting with our indexers.
         """
         return np.array(self)
+
+
+@Substitution(arr=textwrap.dedent("""\
+arr : array-like
+    Must satisfy NumPy's indexing sematnics, including `take`
+    and boolean masking.
+"""))
+@Appender(_take_docstring)
+def take_ea(arr, indexer, fill_value=_default_fill_value):
+    indexer = np.asarray(indexer)
+    if fill_value is _default_fill_value:
+        # NumPy style
+        result = arr.take(indexer)
+    else:
+        mask = indexer == -1
+        if (indexer < -1).any():
+            raise ValueError("Invalid value in 'indexer'. All values "
+                             "must be non-negative or -1. When "
+                             "'fill_value' is specified.")
+
+        # take on empty array not handled as desired by numpy
+        # in case of -1 (all missing take)
+        if not len(arr) and mask.all():
+            return arr._from_sequence([fill_value] * len(indexer))
+
+        result = arr.take(indexer)
+        result[mask] = fill_value
+    return result