Working translation

9 files changed, 83 insertions, 2 deletions

diff --git a/vespajlib/src/main/java/com/yahoo/tensor/functions/CompositeTensorFunction.java b/vespajlib/src/main/java/com/yahoo/tensor/functions/CompositeTensorFunction.java
index fa4a70d264a..23cdc0e6051 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/functions/CompositeTensorFunction.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/functions/CompositeTensorFunction.java
@@ -6,6 +6,6 @@ package com.yahoo.tensor.functions;
  * 
  * @author bratseth
  */
-public abstract class CompositeTensorFunction {
+public abstract class CompositeTensorFunction extends TensorFunction {
 
 }
diff --git a/vespajlib/src/main/java/com/yahoo/tensor/functions/Constant.java b/vespajlib/src/main/java/com/yahoo/tensor/functions/Constant.java
new file mode 100644
index 00000000000..113247be3bb
--- /dev/null
+++ b/vespajlib/src/main/java/com/yahoo/tensor/functions/Constant.java
@@ -0,0 +1,24 @@
+package com.yahoo.tensor.functions;
+
+import com.yahoo.tensor.MapTensor;
+
+/**
+ * A function which returns a constant tensor.
+ * 
+ * @author bratseth
+ */
+public class Constant extends PrimitiveTensorFunction {
+
+    private final MapTensor constant;
+    
+    public Constant(String tensorString) {
+        this.constant = MapTensor.from(tensorString);
+    }
+    
+    @Override
+    public PrimitiveTensorFunction toPrimitive() { return this; }
+
+    @Override
+    public String toString() { return constant.toString(); }
+
+}
diff --git a/vespajlib/src/main/java/com/yahoo/tensor/functions/Join.java b/vespajlib/src/main/java/com/yahoo/tensor/functions/Join.java
index 421ea631ee3..4d945963fdf 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/functions/Join.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/functions/Join.java
@@ -26,5 +26,10 @@ public class Join extends PrimitiveTensorFunction {
     public PrimitiveTensorFunction toPrimitive() {
         return new Join(argumentA.toPrimitive(), argumentB.toPrimitive(), combinator);
     }
+    
+    @Override
+    public String toString() {
+        return "join(" + argumentA.toString() + ", " + argumentB.toString() + ", lambda(a, b) (...))";
+    }
 
 }
diff --git a/vespajlib/src/main/java/com/yahoo/tensor/functions/Map.java b/vespajlib/src/main/java/com/yahoo/tensor/functions/Map.java
index cb0615693ae..22dd08504d7 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/functions/Map.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/functions/Map.java
@@ -26,4 +26,9 @@ public class Map extends PrimitiveTensorFunction {
         return new Map(argument.toPrimitive(), mapper);
     }
 
+    @Override
+    public String toString() {
+        return "map(" + argument.toString() + ", lambda(a) (...))";
+    }
+
 }
diff --git a/vespajlib/src/main/java/com/yahoo/tensor/functions/PrimitiveTensorFunction.java b/vespajlib/src/main/java/com/yahoo/tensor/functions/PrimitiveTensorFunction.java
index 1c41990af23..9c0c9abaeb7 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/functions/PrimitiveTensorFunction.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/functions/PrimitiveTensorFunction.java
@@ -3,6 +3,7 @@ package com.yahoo.tensor.functions;
 /**
  * A primitive tensor function is a tensor function which cannot be expressed in terms of other tensor functions.
  * All tensor implementations must implement all primitive tensor functions.
+ * Primitive tensor functions are fully inspectable.
  * 
  * @author bratseth
  */
diff --git a/vespajlib/src/main/java/com/yahoo/tensor/functions/Product.java b/vespajlib/src/main/java/com/yahoo/tensor/functions/Product.java
index a95eea213c7..09038a294ce 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/functions/Product.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/functions/Product.java
@@ -6,4 +6,22 @@ package com.yahoo.tensor.functions;
  * @author bratseth
  */
 public class Product extends CompositeTensorFunction {
+
+    private final TensorFunction argumentA, argumentB;
+    
+    public Product(TensorFunction argumentA, TensorFunction argumentB) {
+        this.argumentA = argumentA;
+        this.argumentB = argumentB;
+    }
+    
+    @Override
+    public PrimitiveTensorFunction toPrimitive() {
+        return new Join(argumentA.toPrimitive(), argumentB.toPrimitive(), (a, b) -> a * b);
+    }
+
+    @Override
+    public String toString() {
+        return "product(" + argumentA.toString() + ", " + argumentB.toString() + ")";
+    }
+
 }
diff --git a/vespajlib/src/main/java/com/yahoo/tensor/functions/Reduce.java b/vespajlib/src/main/java/com/yahoo/tensor/functions/Reduce.java
index 327234701ad..4b306d376a6 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/functions/Reduce.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/functions/Reduce.java
@@ -30,4 +30,9 @@ public class Reduce extends PrimitiveTensorFunction {
         return new Reduce(argument.toPrimitive(), dimension, reductor, postTransformation);
     }
 
+    @Override
+    public String toString() {
+        return "reduce(" + argument.toString() + ", " + dimension + ", lambda(a, b) (...), lambda(a, b) (...))";
+    }
+
 }
diff --git a/vespajlib/src/main/java/com/yahoo/tensor/functions/TensorFunction.java b/vespajlib/src/main/java/com/yahoo/tensor/functions/TensorFunction.java
index bce2e237e6a..95fca95a042 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/functions/TensorFunction.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/functions/TensorFunction.java
@@ -1,7 +1,7 @@
 package com.yahoo.tensor.functions;
 
 /**
- * An inspectable representation of a tensor function which is able to be translated to a set of primitive
+ * A representation of a tensor function which is able to be translated to a set of primitive
  * tensor functions if necessary.
  * All tensor functions are immutable.
  * 
diff --git a/vespajlib/src/test/java/com/yahoo/tensor/functions/TensorFunctionTestCase.java b/vespajlib/src/test/java/com/yahoo/tensor/functions/TensorFunctionTestCase.java
new file mode 100644
index 00000000000..501397e89bc
--- /dev/null
+++ b/vespajlib/src/test/java/com/yahoo/tensor/functions/TensorFunctionTestCase.java
@@ -0,0 +1,23 @@
+package com.yahoo.tensor.functions;
+
+import org.junit.Test;
+import static org.junit.Assert.assertEquals;
+
+/**
+ * Tests translation of composite to primitive tensor function translation.
+ * 
+ * @author bratseth
+ */
+public class TensorFunctionTestCase {
+
+    @Test
+    public void testTranslation() {
+        assertTranslated("join({{x:1}:1.0}, {{x:2}:1.0}, lambda(a, b) (...))", 
+                         new Product(new Constant("{{x:1}:1.0}"), new Constant("{{x:2}:1.0}")));
+    }
+    
+    private void assertTranslated(String expectedTranslation, TensorFunction inputFunction) {
+        assertEquals(expectedTranslation, inputFunction.toPrimitive().toString());
+    }
+
+}