move axis validation to nv

Author: jbrockmendel

pandas/compat/numpy/function.py

@@ -360,3 +360,22 @@ def validate_resampler_func(method, args, kwargs):
                 "{func}() instead".format(func=method)))
         else:
             raise TypeError("too many arguments passed in")
+
+
+def validate_minmax_axis(axis):
+    """
+    Ensure that the axis argument passed to min, max, argmin, or argmax is
+    zero or None, as otherwise it will be incorrectly ignored.
+
+    Parameters
+    ----------
+    axis : int or None
+
+    Raises
+    ------
+    ValueError
+    """
+    ndim = 1  # hard-coded for Index
+    if axis is not None and axis >= ndim:
+        raise ValueError("`axis` must be fewer than the number of "
+                         "dimensions ({ndim})".format(ndim=ndim))

pandas/core/indexes/datetimelike.py

@@ -430,7 +430,7 @@ def min(self, axis=None, *args, **kwargs):
         --------
         numpy.ndarray.min
         """
-        _validate_minmax_axis(axis)
+        nv.validate_minmax_axis(axis)
         nv.validate_min(args, kwargs)
 
         try:
@@ -459,7 +459,7 @@ def argmin(self, axis=None, *args, **kwargs):
         --------
         numpy.ndarray.argmin
         """
-        _validate_minmax_axis(axis)
+        nv.validate_minmax_axis(axis)
         nv.validate_argmin(args, kwargs)
 
         i8 = self.asi8
@@ -480,7 +480,7 @@ def max(self, axis=None, *args, **kwargs):
         --------
         numpy.ndarray.max
         """
-        _validate_minmax_axis(axis)
+        nv.validate_minmax_axis(axis)
         nv.validate_max(args, kwargs)
 
         try:
@@ -509,7 +509,7 @@ def argmax(self, axis=None, *args, **kwargs):
         --------
         numpy.ndarray.argmax
         """
-        _validate_minmax_axis(axis)
+        nv.validate_minmax_axis(axis)
         nv.validate_argmax(args, kwargs)
 
         i8 = self.asi8
@@ -710,25 +710,6 @@ def _time_shift(self, periods, freq=None):
         return result
 
 
-def _validate_minmax_axis(axis):
-    """
-    Ensure that the axis argument passed to min, max, argmin, or argmax is
-    zero or None, as otherwise it will be incorrectly ignored.
-
-    Parameters
-    ----------
-    axis : int or None
-
-    Raises
-    ------
-    ValueError
-    """
-    ndim = 1  # hard-coded for Index
-    if axis is not None and axis >= ndim:
-        raise ValueError("`axis` must be fewer than the number of "
-                         "dimensions ({ndim})".format(ndim=ndim))
-
-
 def _ensure_datetimelike_to_i8(other, to_utc=False):
     """
     helper for coercing an input scalar or array to i8