Add trunc.

theano/scalar/basic.py

@@ -1719,6 +1719,18 @@ class Floor(UnaryScalarOp):
 floor = Floor(same_out_nocomplex, name='floor')
 
 
+class Trunc(UnaryScalarOp):
+    def impl(self, x):
+        return numpy.trunc(x)
+
+    def grad(self, (x,), (gz,)):
+        return None,
+
+    def c_code(self, node, name, (x,), (z,), sub):
+        return "%(z)s = %(x)s >= 0? floor(%(x)s): -floor(-%(x)s);" % locals()
+trunc = Trunc(same_out_nocomplex, name='trunc')
+
+
 class RoundHalfToEven(UnaryScalarOp):
     """
     This function implement the same rounding than numpy: Round half to even

theano/tensor/basic.py

@@ -2630,6 +2630,11 @@ def floor(a):
     """floor of a"""
 
 
+@_scal_elemwise_with_nfunc('trunc', 1, 1)
+def trunc(a):
+    """trunc of a"""
+
+
 @constructor
 def iround(a, mode="half_away_from_zero"):
     """cast(round(a,mode),'int64')"""

theano/tensor/inplace.py

@@ -131,6 +131,10 @@ def ceil_inplace(a):
 def floor_inplace(a):
     """floor of `a` (inplace on `a`)"""
 
+@_scal_inplace
+def trunc_inplace(a):
+    """trunc of `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

@@ -909,6 +909,16 @@ FloorTester = makeBroadcastTester(op=tensor.floor,
         #      yet it does not...
         grad=_grad_broadcast_unary_normal)
 
+TruncInplaceTester = makeBroadcastTester(
+    op=inplace.floor_inplace,
+    expected=lambda a: numpy.asarray(numpy.floor(a), a.dtype),
+    good=_good_broadcast_unary_normal_no_complex,
+    inplace=True)
+TruncTester = makeBroadcastTester(
+    op=tensor.floor,
+    expected=lambda a: numpy.asarray(numpy.floor(a), a.dtype),
+    good=_good_broadcast_unary_normal_no_complex)
+
 FloorInplaceTester = makeBroadcastTester(op=inplace.floor_inplace,
         expected=lambda a: numpy.asarray(numpy.floor(a), a.dtype),
         good=_good_broadcast_unary_normal_no_complex,