added tensor.round and tensor.iround and their doc.

doc/library/tensor/basic.txt

@@ -954,9 +954,13 @@ Mathematical
 
     Returns a variable representing the floor of a (for example floor(2.9) is 2).
 
-.. function:: iround(a)
+.. function:: round(a, mode="half_away_from_zero")
 
-    Returns a variable representing the of rounding of a, ie int(a).
+    Returns a variable representing the rounding of a in the same dtype as a. Implemented rounding mode are half_away_from_zero and half_to_even.
+
+.. function:: iround(a, mode="half_away_from_zero")
+
+    Short hand for cast(round(a, mode),'int64').
 
 .. function:: sqr(a)
 

theano/scalar/basic.py

@@ -1145,13 +1145,6 @@ class Floor(UnaryScalarOp):
         return "%(z)s = floor(%(x)s);" % locals()
 floor = Floor(same_out_nocomplex, name = 'floor')
 
-class IRound(UnaryScalarOp):
-    def impl(self, x):
-        return theano._asarray(numpy.round(x), dtype = 'int64')
-    def c_code(self, node, name, (x, ), (z, ), sub):
-        return "%(z)s = round(%(x)s);" % locals()
-iround = IRound(int_out_nocomplex)
-
 class RoundHalfToEven(UnaryScalarOp):
     """
     This function implement the same rounding than numpy: Round half to even

theano/tensor/basic.py

@@ -1574,9 +1574,20 @@ def ceil(a):
 def floor(a):
     """floor of a"""
 
-@_scal_elemwise
-def iround(a):
-    """int(round(a))"""
+@constructor
+def iround(a, mode="half_away_from_zero"):
+    """cast(round(a,mode),'int64')"""
+    return cast(round(a,mode),'int64')
+
+@constructor
+def round(a, mode="half_away_from_zero"):
+    """round_mode(a) with mode in [half_away_from_zero, half_to_even]"""
+    if mode == "half_away_from_zero":
+        return round_half_away_from_zero(a)
+    elif mode == "half_to_even":
+        return round_half_to_even(a)
+    else:
+        raise Exception("round mode %s is not implemented."%mode)
 
 @_scal_elemwise
 def round_half_to_even(a):

theano/tensor/inplace.py

@@ -124,10 +124,6 @@ def ceil_inplace(a):
 def floor_inplace(a):
     """floor of `a` (inplace on `a`)"""
 
-@_scal_inplace
-def iround_inplace(a):
-    """int(round(a)) (inplace on `a`)"""
-
 @_scal_inplace
 def round_half_to_even_inplace(a):
     """round_half_to_even_inplace(a) (inplace on `a`)"""

theano/tensor/tests/test_basic.py

@@ -445,14 +445,6 @@ FloorInplaceTester = makeBroadcastTester(op = inplace.floor_inplace,
                                          grad = _grad_broadcast_unary_normal,
                                          inplace = True)
 
-IRoundTester = makeBroadcastTester(op = iround,
-                                  expected = lambda a: numpy.asarray(numpy.round(a),dtype='int64'),
-                                  good = _good_broadcast_unary_normal)
-IRoundInplaceTester = makeBroadcastTester(op = inplace.iround_inplace,
-                                         expected = lambda a: numpy.asarray(numpy.round(a),dtype='int64'),
-                                         good = _good_broadcast_unary_normal,
-                                         inplace = True)
-
 RoundHalfToEvenTester = makeBroadcastTester(op = round_half_to_even,
                                   expected = numpy.round,
                                   good = _good_broadcast_unary_normal_float)