Fix numexpr version issue

Author: anjsudh

pandas/core/computation/ops.py

@@ -15,7 +15,6 @@
 import pandas as pd
 from pandas.core.base import StringMixin
 import pandas.core.common as com
-from pandas.core.computation.check import _NUMEXPR_INSTALLED, _NUMEXPR_VERSION
 from pandas.core.computation.common import _ensure_decoded, _result_type_many
 from pandas.core.computation.scope import _DEFAULT_GLOBALS
 
@@ -25,10 +24,10 @@
 
 _unary_math_ops = ('sin', 'cos', 'exp', 'log', 'expm1', 'log1p',
                    'sqrt', 'sinh', 'cosh', 'tanh', 'arcsin', 'arccos',
-                   'arctan', 'arccosh', 'arcsinh', 'arctanh', 'abs', 'log10')
+                   'arctan', 'arccosh', 'arcsinh', 'arctanh', 'abs', 'log10',
+                   'floor', 'ceil'
+                   )
 _binary_math_ops = ('arctan2',)
-if _NUMEXPR_INSTALLED and _NUMEXPR_VERSION >= LooseVersion('2.6.9'):
-    _unary_math_ops += ('floor', 'ceil')
 
 _mathops = _unary_math_ops + _binary_math_ops
 
@@ -544,9 +543,12 @@ def __unicode__(self):
 
 
 class FuncNode(object):
-
     def __init__(self, name):
-        if name not in _mathops:
+        from pandas.core.computation.check import _NUMEXPR_INSTALLED, _NUMEXPR_VERSION
+        if name not in _mathops or (
+                _NUMEXPR_INSTALLED and _NUMEXPR_VERSION < LooseVersion('2.6.9') and
+                name in ('floor', 'ceil')
+        ):
             raise ValueError(
                 "\"{0}\" is not a supported function".format(name))
 

pandas/tests/computation/test_eval.py

@@ -63,6 +63,16 @@ def ne_lt_2_6_9():
         pytest.skip("numexpr is >= 2.6.9")
     return 'numexpr'
 
+@pytest.fixture
+def unary_fns_for_ne():
+    if _NUMEXPR_INSTALLED :
+        if _NUMEXPR_VERSION >= LooseVersion('2.6.9'):
+            return _unary_math_ops
+        else:
+            return tuple(x for x in _unary_math_ops if x not in ("floor","ceil"))
+    else:
+        pytest.skip("numexpr is not present")
+
 
 def engine_has_neg_frac(engine):
     return _engines[engine].has_neg_frac
@@ -1632,18 +1642,18 @@ def eval(self, *args, **kwargs):
         kwargs['level'] = kwargs.pop('level', 0) + 1
         return pd.eval(*args, **kwargs)
 
-    def test_unary_functions(self):
+    def test_unary_functions(self, unary_fns_for_ne):
         df = DataFrame({'a': np.random.randn(10)})
         a = df.a
 
-        for fn in self.unary_fns:
+        for fn in unary_fns_for_ne:
             expr = "{0}(a)".format(fn)
             got = self.eval(expr)
             with np.errstate(all='ignore'):
                 expect = getattr(np, fn)(a)
             tm.assert_series_equal(got, expect, check_names=False)
 
-    def test_floor_and_ceil_functions_raise_error(self, ne_lt_2_6_9):
+    def test_floor_and_ceil_functions_raise_error(self, ne_lt_2_6_9, unary_fns_for_ne):
         for fn in ('floor', 'ceil'):
             msg = "\"{0}\" is not a supported function".format(fn)
             with pytest.raises(ValueError, match=msg):