DEPR: deprecate .ix in favor of .loc/.iloc

closes pandas-dev#14218

Author: jreback

pandas/core/indexing.py

@@ -1,5 +1,6 @@
 # pylint: disable=W0223
 
+import warnings
 import numpy as np
 from pandas.compat import range, zip
 import pandas.compat as compat
@@ -1279,6 +1280,14 @@ class _IXIndexer(_NDFrameIndexer):
 
     """
 
+    def __init__(self, obj, name):
+        warnings.warn(".ix is deprecated. Please use\n"
+                      ".loc for label based indexing or\n"
+                      ".iloc for positional indexing\n",
+                      FutureWarning, stacklevel=3)
+
+        super(_IXIndexer, self).__init__(obj, name)
+
     def _has_valid_type(self, key, axis):
         if isinstance(key, slice):
             return True