ENH: support alignable panel arithmetic methods

Author: jreback

pandas/core/panel.py

@@ -92,13 +92,8 @@ def panel_index(time, panels, names=['time', 'panel']):
 
 
 def _arith_method(func, name):
-    # work only for scalars
 
     def f(self, other):
-        if not np.isscalar(other):
-            raise ValueError('Simple arithmetic with %s can only be '
-                             'done with scalar values' % self._constructor.__name__)
-
         return self._combine(other, func)
     f.__name__ = name
     return f

pandas/tests/test_panel.py

@@ -266,8 +266,6 @@ def test_arith(self):
         self._test_op(self.panel, lambda x, y: x / y)  # panel / 1
         self._test_op(self.panel, lambda x, y: x ** y)  # panel ** 1
 
-        self.assertRaises(Exception, self.panel.__add__, self.panel['ItemA'])
-
     @staticmethod
     def _test_op(panel, op):
         result = op(panel, 1)