More tests

2 files changed, 11 insertions, 2 deletions

diff --git a/vespajlib/src/main/java/com/yahoo/tensor/Tensor.java b/vespajlib/src/main/java/com/yahoo/tensor/Tensor.java
index 9863303caa2..4b17f65ea21 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/Tensor.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/Tensor.java
@@ -70,7 +70,12 @@ public interface Tensor {
     default Tensor join(Tensor argument, DoubleBinaryOperator combinator) {
         return new Join(new ConstantTensor(this), new ConstantTensor(argument), combinator).evaluate();
     }
-    
+
+    default Tensor rename(String fromDimension, String toDimension) {
+        return new Rename(new ConstantTensor(this), Collections.singletonList(fromDimension), 
+                                                    Collections.singletonList(toDimension)).evaluate();
+    }
+
     default Tensor rename(List<String> fromDimensions, List<String> toDimensions) {
         return new Rename(new ConstantTensor(this), fromDimensions, toDimensions).evaluate();
     }
diff --git a/vespajlib/src/test/java/com/yahoo/tensor/TensorTestCase.java b/vespajlib/src/test/java/com/yahoo/tensor/TensorTestCase.java
index 1b5507c1341..e403bb56d56 100644
--- a/vespajlib/src/test/java/com/yahoo/tensor/TensorTestCase.java
+++ b/vespajlib/src/test/java/com/yahoo/tensor/TensorTestCase.java
@@ -1,5 +1,6 @@
 package com.yahoo.tensor;
 
+import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import static org.junit.Assert.assertEquals;
 
@@ -18,7 +19,10 @@ public class TensorTestCase {
         assertEquals(MapTensor.from("{ {x:1,y:1}:15, {x:2,y:1}:35 }"), tensor1.multiply(tensor2));
         assertEquals(MapTensor.from("{ {x:1,y:1}:12, {x:2,y:1}:28 }"), tensor1.join(tensor2, (a, b) -> a * b - a ));
         assertEquals(MapTensor.from("{ {x:1,y:1}:0, {x:2,y:1}:1 }"), tensor1.larger(tensor2));
-        assertEquals(MapTensor.from("{{y:1}:50.0}"), tensor1.matmul(tensor2, "x"));
+        assertEquals(MapTensor.from("{ {y:1}:50.0 }"), tensor1.matmul(tensor2, "x"));
+        assertEquals(MapTensor.from("{ {z:1}:3, {z:2}:7 }"), tensor1.rename("x", "z"));
+        assertEquals(MapTensor.from("{ {y:1,x:1}:8, {y:2,x:1}:12 }"), tensor1.add(tensor2).rename(ImmutableList.of("x", "y"),
+                                                                                                  ImmutableList.of("y", "x")));
     }
 
 }