Started implementation of Take Op.

theano/tensor/basic.py

@@ -6811,6 +6811,45 @@ class AdvancedIncSubtensor(Op):
                               *inputs[2:]).outputs
 advanced_inc_subtensor = AdvancedIncSubtensor()
 
+class Take(Op):
+    """
+    Take elements from an array along an axis.
+    """
+    def __init__(self, axis, mode):
+        self.axis = axis
+        self.mode = mode
+
+    def __eq__(self, other):
+        return (type(self) == type(other) and
+                self.axis == other.axis and
+                self.mode == other.mode)
+
+    def __hash__(self):
+        return hash((type(self), self.axis, self.mode))
+
+    def make_node(self, a, indices):
+        a = as_tensor_variable(a)
+        indices = as_tensor_variable(indices)
+        return gof.Apply(self, (a, indices), [a.type()])
+ 
+    def perform(self, node, inputs, outputs):
+        a, indices = inputs
+        out, = outputs
+        out[0] = a.take(indices, axis=self.axis, mode=self.mode)
+
+    def infer_shape(self, node, input_shapes):
+        a_shape, indices_shape = input_shapes
+        if self.axis is None:
+            shape = indices_shape
+        else:
+            shape = a_shape[:self.axis] + indices_shape + a_shape[self.axis+1:]
+        return [shape]
+
+            
+
+def take(a, indices, axis=None, mode='raise'):
+    return Take(axis, mode)(a, indices)
+    
 #########################
 # Linalg : Dot
 #########################