Add OutputVector class and a more complex example to Tensorflow

CHANGELOG.md

@@ -1,4 +1,5 @@
 
+ * Add more samples for TensorFlow including a complete training example ([pull #563](https://github.com/bytedeco/javacpp-presets/pull/563))
  * Add helper for `PIX`, `FPIX`, and `DPIX` of Leptonica, facilitating access to image data of Tesseract ([issue #517](https://github.com/bytedeco/javacpp-presets/issues/517))
  * Add presets for the NVBLAS, NVGRAPH, NVRTC, and NVML modules of CUDA ([issue deeplearning4j/nd4j#2895](https://github.com/deeplearning4j/nd4j/issues/2895))
  * Link OpenBLAS with `-Wl,-z,noexecstack` on `linux-armhf` as required by the JDK ([issue deeplearning4j/libnd4j#700](https://github.com/deeplearning4j/libnd4j/issues/700))

tensorflow/samples/pom.xml

@@ -0,0 +1,24 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>org.bytedeco.javacpp-presets</groupId>
+    <artifactId>tensorflow-samples</artifactId>
+    <version>1.8.0-1.4.2-SNAPSHOT</version>
+    <name>JavaCPP Presets Samples for TensorFlow</name>
+
+    <properties>
+        <maven.compiler.target>1.7</maven.compiler.target>
+        <maven.compiler.source>1.7</maven.compiler.source>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>${project.groupId}</groupId>
+            <artifactId>tensorflow-platform</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+    </dependencies>
+
+</project>

tensorflow/samples/src/main/java/org/bytedeco/javacpp/samples/tensorflow/AddNExample.java

@@ -0,0 +1,83 @@
+package org.bytedeco.javacpp.samples.tensorflow;
+
+import static org.bytedeco.javacpp.tensorflow.Const;
+import static org.bytedeco.javacpp.tensorflow.InitMain;
+import static org.bytedeco.javacpp.tensorflow.TF_CHECK_OK;
+
+import java.nio.IntBuffer;
+
+import org.bytedeco.javacpp.Loader;
+import org.bytedeco.javacpp.tensorflow.AddN;
+import org.bytedeco.javacpp.tensorflow.GraphDef;
+import org.bytedeco.javacpp.tensorflow.Input;
+import org.bytedeco.javacpp.tensorflow.InputList;
+import org.bytedeco.javacpp.tensorflow.L2Loss;
+import org.bytedeco.javacpp.tensorflow.Output;
+import org.bytedeco.javacpp.tensorflow.OutputVector;
+import org.bytedeco.javacpp.tensorflow.Scope;
+import org.bytedeco.javacpp.tensorflow.Session;
+import org.bytedeco.javacpp.tensorflow.SessionOptions;
+import org.bytedeco.javacpp.tensorflow.StringTensorPairVector;
+import org.bytedeco.javacpp.tensorflow.StringVector;
+import org.bytedeco.javacpp.tensorflow.Tensor;
+import org.bytedeco.javacpp.tensorflow.TensorShape;
+import org.bytedeco.javacpp.tensorflow.TensorVector;
+
+/**
+ * Showcase the usage of OutputVector and the AddN operator.
+ *
+ * @author Nico Hezel
+ */
+public class AddNExample {
+
+    public static void main(String[] args) {
+
+        // Load all javacpp-preset classes and native libraries
+        Loader.load(org.bytedeco.javacpp.tensorflow.class);
+
+        // Platform-specific initialization routine
+        InitMain("trainer", (int[])null, null);
+
+        // Create a new empty graph
+        Scope scope = Scope.NewRootScope();
+
+        // (2,1) matrix of ones, sixes and tens
+        TensorShape shape = new TensorShape(2, 1);
+        Output ones = Const(scope.WithOpName("ones"), 1, shape);
+        Output sixes = Const(scope.WithOpName("sixes"), 6, shape);
+        Output tens = Const(scope.WithOpName("tens"), 10, shape);
+
+        // Adding all matrices element-wise
+        OutputVector ov = new OutputVector(ones, sixes, tens);
+        InputList inputList = new InputList(ov);
+        AddN add = new AddN(scope.WithOpName("add"), inputList);
+
+        // Build a graph definition object
+        GraphDef def = new GraphDef();
+        TF_CHECK_OK(scope.ToGraphDef(def));
+
+        // Creates a session.
+        SessionOptions options = new SessionOptions();
+        try(final Session session = new Session(options)) {
+
+            // Create the graph to be used for the session.
+            TF_CHECK_OK(session.Create(def));
+
+            // Input and output of a single session run.
+            StringTensorPairVector input_feed = new StringTensorPairVector();
+            StringVector output_tensor_name = new StringVector("add:0");
+            StringVector target_tensor_name = new StringVector();
+            TensorVector outputs = new TensorVector();
+
+            // Run the session once
+            TF_CHECK_OK(session.Run(input_feed, output_tensor_name, target_tensor_name, outputs));
+
+            // Print the add-output
+            for (Tensor output : outputs.get()) {
+                IntBuffer y_flat = output.createBuffer();
+                for (int i = 0; i < output.NumElements(); i++)
+                    System.out.println(y_flat.get(i));
+            }
+        }
+    }
+}