Go: Add PartialRun support.

Change: 147783087

1 files changed, 65 insertions, 0 deletions

diff --git a/tensorflow/go/session_test.go b/tensorflow/go/session_test.go
index 14ecca402b..9afa2be3b4 100644
--- a/tensorflow/go/session_test.go
+++ b/tensorflow/go/session_test.go
@@ -181,3 +181,68 @@ func TestConcurrency(t *testing.T) {
 		t.Errorf("Close() 2: %v", err)
 	}
 }
+
+func ExamplePartialRun() {
+	var (
+		// Create a graph: a + 2 + 3 + b.
+		//
+		// Skipping error handling for brevity of this example.
+		// The 'op' package can be used to make graph construction code
+		// with error handling more succinct.
+		g        = NewGraph()
+		a, _     = Placeholder(g, "a", Int32)
+		b, _     = Placeholder(g, "b", Int32)
+		two, _   = Const(g, "Two", int32(2))
+		three, _ = Const(g, "Three", int32(3))
+
+		plus2, _ = Add(g, "plus2", a, two)       // a + 2
+		plus3, _ = Add(g, "plus3", plus2, three) // (a + 2) + 3
+		plusB, _ = Add(g, "plusB", plus3, b)     // ((a + 2) + 3) + b
+
+	)
+	sess, err := NewSession(g, nil)
+	if err != nil {
+		panic(err)
+	}
+	defer sess.Close()
+
+	// All the feeds, fetches and targets for subsequent PartialRun.Run
+	// calls must be provided at setup.
+	pr, err := sess.NewPartialRun(
+		[]Output{a, b},
+		[]Output{plus2, plusB},
+		[]*Operation{plus3.Op},
+	)
+	if err != nil {
+		panic(err)
+	}
+
+	// Feed 'a=1', fetch 'plus2', and compute (but do not fetch) 'plus3'.
+	// Imagine this to be the forward pass of unsupervised neural network
+	// training of a robot.
+	val, _ := NewTensor(int32(1))
+	fetches, err := pr.Run(
+		map[Output]*Tensor{a: val},
+		[]Output{plus2},
+		nil)
+	if err != nil {
+		panic(err)
+	}
+	v1 := fetches[0].Value().(int32)
+
+	// Now, feed 'b=4', fetch 'plusB=a+2+3+b'
+	// Imagine this to be the result of actuating the robot to determine
+	// the error produced by the current state of the neural network.
+	val, _ = NewTensor(int32(4))
+	fetches, err = pr.Run(
+		map[Output]*Tensor{b: val},
+		[]Output{plusB},
+		nil)
+	if err != nil {
+		panic(err)
+	}
+	v2 := fetches[0].Value().(int32)
+
+	fmt.Println(v1, v2)
+	// Output: 3 10
+}