go: Add an example.

Add an example (that will appear in Go doc) for a real use of the Go TensorFlow
APIs - using a pre-defined image recognition model for inference.

While at it a couple of minor tweaks:
- NewSession now accepts 'nil' for options as the documentation says it does
- Convenience accessors for the Outputs of an Operation
- Ability to extract (possibly partial) shapes from an Output

Another step towards #10
Change: 134560938

1 files changed, 10 insertions, 8 deletions

diff --git a/tensorflow/go/util_test.go b/tensorflow/go/util_test.go
index 2b13df008a..06b4e61d0f 100644
--- a/tensorflow/go/util_test.go
+++ b/tensorflow/go/util_test.go
@@ -18,18 +18,20 @@ func Placeholder(g *Graph, name string, dt DataType) (Output, error) {
 	b := newOpBuilder(g, "Placeholder", name)
 	b.SetAttrType("dtype", dt)
 	op, err := b.Build()
-	if err != nil {
-		return Output{}, err
-	}
-	return Output{op, 0}, nil
+	return Output{op, 0}, err
+}
+
+func Const(g *Graph, name string, t *Tensor) (Output, error) {
+	b := newOpBuilder(g, "Const", name)
+	b.SetAttrType("dtype", t.DataType())
+	b.SetAttrTensor("value", t)
+	op, err := b.Build()
+	return Output{op, 0}, err
 }
 
 func Neg(g *Graph, name string, port Output) (Output, error) {
 	b := newOpBuilder(g, "Neg", name)
 	b.AddInput(port)
 	op, err := b.Build()
-	if err != nil {
-		return Output{}, err
-	}
-	return Output{op, 0}, nil
+	return Output{op, 0}, err
 }