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diff --git a/vespajlib/src/main/java/com/yahoo/tensor/MapTensorBuilder.java b/vespajlib/src/main/java/com/yahoo/tensor/MapTensorBuilder.java
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+++ b/vespajlib/src/main/java/com/yahoo/tensor/MapTensorBuilder.java
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+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.tensor;
+
+import com.google.common.annotations.Beta;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Builder class for a MapTensor.
+ *
+ * The set of dimensions of the resulting tensor is the union of
+ * the dimensions specified explicitly and the ones specified in the
+ * tensor cell addresses.
+ *
+ * @author <a href="mailto:geirst@yahoo-inc.com">Geir Storli</a>
+ */
+@Beta
+public class MapTensorBuilder {
+
+    private final Set<String> dimensions = new HashSet<>();
+    private final Map<TensorAddress, Double> cells = new HashMap<>();
+
+    public class CellBuilder {
+
+        private final TensorAddress.Builder addressBuilder = new TensorAddress.Builder();
+
+        public CellBuilder label(String dimension, String label) {
+            dimensions.add(dimension);
+            addressBuilder.add(dimension, label);
+            return this;
+        }
+        public MapTensorBuilder value(double cellValue) {
+            cells.put(addressBuilder.build(), cellValue);
+            return MapTensorBuilder.this;
+        }
+    }
+
+    public MapTensorBuilder() {
+    }
+
+    public MapTensorBuilder dimension(String dimension) {
+        dimensions.add(dimension);
+        return this;
+    }
+
+    public CellBuilder cell() {
+        return new CellBuilder();
+    }
+
+    public Tensor build() {
+        return new MapTensor(dimensions, cells);
+    }
+}