[Py] Enable ngraph-cpp ops in Python API (#820)

* Enable BatchNorm op

* Enable function call op

* Enable get output element op

python/ngraph/__init__.py

@@ -22,6 +22,7 @@ from ngraph.ops import add
 from ngraph.ops import asin
 from ngraph.ops import atan
 from ngraph.ops import avg_pool
+from ngraph.ops import batch_norm
 from ngraph.ops import broadcast
 from ngraph.ops import ceiling
 from ngraph.ops import ceiling as ceil
@@ -35,7 +36,9 @@ from ngraph.ops import divide
 from ngraph.ops import dot
 from ngraph.ops import equal
 from ngraph.ops import exp
+from ngraph.ops import function_call
 from ngraph.ops import floor
+from ngraph.ops import get_output_element
 from ngraph.ops import greater
 from ngraph.ops import greater_eq
 from ngraph.ops import less

python/ngraph/ops.py

@@ -20,11 +20,12 @@ import numpy as np
 from ngraph.impl import AxisSet, AxisVector, Coordinate, CoordinateDiff, Node, NodeVector, \
     Shape, Strides
 
-from ngraph.impl.op import Abs, Acos, Add, Asin, Atan, AvgPool, Broadcast, Ceiling, Concat, \
-    Constant, Convert, Convolution, Cos, Cosh, Divide, Dot, Equal, Exp, Floor, Greater, GreaterEq,\
-    Less, LessEq, Log, Max, Maximum, MaxPool, Min, Minimum, Multiply, Negative, Not, NotEqual, \
-    OneHot, Pad, Parameter, Product, Power, Relu, ReplaceSlice, Reshape, Reverse, Select, \
-    Sign, Sin, Sinh, Slice, Softmax, Sqrt, Subtract, Sum, Tan, Tanh
+from ngraph.impl.op import Abs, Acos, Add, Asin, Atan, AvgPool, BatchNorm, Broadcast, Ceiling,\
+    Concat, Constant, Convert, Convolution, Cos, Cosh, Divide, Dot, Equal, Exp, Floor, \
+    FunctionCall, GetOutputElement, Greater, GreaterEq, Less, LessEq, Log, Max, Maximum, MaxPool, \
+    Min, Minimum, Multiply, Negative, Not, NotEqual, OneHot, Pad, Parameter, Product, Power, Relu, \
+    ReplaceSlice, Reshape, Reverse, Select, Sign, Sin, Sinh, Slice, Softmax, Sqrt, Subtract, Sum, \
+    Tan, Tanh
 
 from typing import Iterable, List
 
@@ -761,3 +762,33 @@ def reverse(node, reversed_axes, name=None):  # type: (Node, List[int], str) ->
     :return: The new node with reversed axes.
     """
     return Reverse(node, AxisSet(reversed_axes))
+
+
+@nameable_op
+def batch_norm(eps,             # type: float
+               gamma,           # type: Node
+               beta,            # type: Node
+               data,            # type: Node
+               mean=None,       # type: Node
+               variance=None,   # type: Node
+               training=False,  # type: bool
+               name=None,       # type: str
+               ):
+    # type: (...) -> Node
+    """Return batch normalization node."""
+    if mean is None and variance is None:
+        return BatchNorm(eps, gamma, beta, data)
+    else:
+        return BatchNorm(eps, gamma, beta, data, mean, variance, training)
+
+
+@nameable_op
+def function_call(function_to_call, args):  # type: (Node, NodeVector) -> Node
+    """Return Function call op."""
+    return FunctionCall(function_to_call, args)
+
+
+@nameable_op
+def get_output_element(data, index):  # type: (Node, int) -> Node
+    """Return the `n`th element of the input tuple."""
+    return GetOutputElement(data, index)

python/pyngraph/ops/batch_norm.cpp

@@ -33,6 +33,14 @@ void regclass_pyngraph_op_BatchNorm(py::module m)
                             const std::shared_ptr<ngraph::Node>&,
                             const std::shared_ptr<ngraph::Node>&,
                             const std::shared_ptr<ngraph::Node>&>());
+
+    batch_norm.def(py::init<double,
+                            const std::shared_ptr<ngraph::Node>&,
+                            const std::shared_ptr<ngraph::Node>&,
+                            const std::shared_ptr<ngraph::Node>&,
+                            const std::shared_ptr<ngraph::Node>&,
+                            const std::shared_ptr<ngraph::Node>&,
+                            bool&>());
 }
 
 void regclass_pyngraph_op_BatchNormBackprop(py::module m)

python/test/ngraph/test_basic.py

@@ -19,6 +19,7 @@ import json
 
 import ngraph as ng
 from test.ngraph.util import get_runtime, run_op_node
+from ngraph.impl import Function, NodeVector
 
 
 @pytest.mark.parametrize('dtype', [np.float32, np.float64,
@@ -48,6 +49,26 @@ def test_simple_computation_on_ndarrays(dtype):
     assert np.allclose(result, np.array([[630, 704], [782, 864]], dtype=dtype))
 
 
+def test_function_call():
+    runtime = get_runtime()
+    dtype = int
+    shape = [2, 2]
+    parameter_a = ng.parameter(shape, dtype=dtype, name='A')
+    parameter_b = ng.parameter(shape, dtype=dtype, name='B')
+    parameter_c = ng.parameter(shape, dtype=dtype, name='C')
+    parameter_list = [parameter_a, parameter_b, parameter_c]
+    ops = ((parameter_a + parameter_b) * parameter_c)
+    func = Function(NodeVector([ops]), parameter_list, 'addmul')
+    fc = ng.function_call(func, NodeVector(parameter_list))
+    computation = runtime.computation(fc, parameter_a, parameter_b, parameter_c)
+
+    value_a = np.array([[1, 2], [3, 4]], dtype=dtype)
+    value_b = np.array([[5, 6], [7, 8]], dtype=dtype)
+    value_c = np.array([[9, 10], [11, 12]], dtype=dtype)
+    result = computation(value_a, value_b, value_c)
+    assert np.allclose(result, np.array([[54, 80], [110, 144]], dtype=dtype))
+
+
 def test_serialization():
     dtype = np.float32
     manager_name = pytest.config.getoption('backend', default='CPU')