fix boolean ops to return the input element::type instead of float32 (#356)

src/ngraph/ops/maximum.cpp

@@ -28,9 +28,8 @@ void ngraph::op::Maximum::generate_adjoints(autodiff::Adjoints& adjoints,
 {
     auto x = get_input_op(0);
     auto y = get_input_op(1);
-
     adjoints.add_delta(
-        x, delta * make_shared<op::Convert>(make_shared<op::Greater>(x, y), element::f32));
+        x, delta * make_shared<op::Convert>(make_shared<op::Greater>(x, y), x->get_element_type()));
     adjoints.add_delta(
-        y, delta * make_shared<op::Convert>(make_shared<op::Greater>(y, x), element::f32));
+        y, delta * make_shared<op::Convert>(make_shared<op::Greater>(y, x), y->get_element_type()));
 }

src/ngraph/ops/minimum.cpp

@@ -29,8 +29,8 @@ void ngraph::op::Minimum::generate_adjoints(autodiff::Adjoints& adjoints,
     auto x = get_input_op(0);
     auto y = get_input_op(1);
 
-    adjoints.add_delta(x,
-                       delta * make_shared<op::Convert>(make_shared<op::Less>(x, y), element::f32));
-    adjoints.add_delta(y,
-                       delta * make_shared<op::Convert>(make_shared<op::Less>(y, x), element::f32));
+    adjoints.add_delta(
+        x, delta * make_shared<op::Convert>(make_shared<op::Less>(x, y), x->get_element_type()));
+    adjoints.add_delta(
+        y, delta * make_shared<op::Convert>(make_shared<op::Less>(y, x), y->get_element_type()));
 }

src/ngraph/ops/select.cpp

@@ -56,9 +56,10 @@ void ngraph::op::Select::generate_adjoints(autodiff::Adjoints& adjoints,
     auto x = get_inputs().at(1).get_output().get_node();
     auto y = get_inputs().at(2).get_output().get_node();
 
-    auto p_as_float = std::make_shared<op::Convert>(p, element::f32);
-    auto not_p_as_float = std::make_shared<op::Convert>(std::make_shared<op::Not>(p), element::f32);
+    auto p_as_x_type = std::make_shared<op::Convert>(p, x->get_element_type());
+    auto not_p_as_y_type =
+        std::make_shared<op::Convert>(std::make_shared<op::Not>(p), y->get_element_type());
 
-    adjoints.add_delta(x, delta * p_as_float);
-    adjoints.add_delta(y, delta * not_p_as_float);
+    adjoints.add_delta(x, delta * p_as_x_type);
+    adjoints.add_delta(y, delta * not_p_as_y_type);
 }