Add dynamically settable default

3 files changed, 74 insertions, 12 deletions

diff --git a/model-evaluation/src/main/java/ai/vespa/models/evaluation/FunctionEvaluator.java b/model-evaluation/src/main/java/ai/vespa/models/evaluation/FunctionEvaluator.java
index caa2db13ff2..c0f96dfb161 100644
--- a/model-evaluation/src/main/java/ai/vespa/models/evaluation/FunctionEvaluator.java
+++ b/model-evaluation/src/main/java/ai/vespa/models/evaluation/FunctionEvaluator.java
@@ -60,10 +60,31 @@ public class FunctionEvaluator {
         return bind(name, Tensor.Builder.of(TensorType.empty).cell(value).build());
     }
 
+    /**
+     * Sets the default value to use for variables which are not bound
+     *
+     * @param value the default value
+     * @return this for chaining
+     */
+    public FunctionEvaluator setUnboundValue(Tensor value) {
+        if (evaluated)
+            throw new IllegalStateException("Cannot change the unbound value in a used evaluator");
+        context.setUnboundValue(value);
+        return this;
+    }
+
+    /**
+     * Sets the default value to use for variables which are not bound
+     *
+     * @param value the default value
+     * @return this for chaining
+     */
+    public FunctionEvaluator setUnboundValue(double value) {
+        return setUnboundValue(Tensor.Builder.of(TensorType.empty).cell(value).build());
+    }
+
     public Tensor evaluate() {
         for (Map.Entry<String, TensorType> argument : function.argumentTypes().entrySet()) {
-            System.out.println("Checking " + argument.getKey() + " default " + context.defaultValue() + " is assignable to " + argument.getValue() +
-                               "? " + context.defaultValue().type().isAssignableTo(argument.getValue()));
             if (context.isMissing(argument.getKey()))
                 throw new IllegalStateException("Missing argument '" + argument.getKey() +
                                                 "': Must be bound to a value of type " + argument.getValue());
diff --git a/model-evaluation/src/main/java/ai/vespa/models/evaluation/LazyArrayContext.java b/model-evaluation/src/main/java/ai/vespa/models/evaluation/LazyArrayContext.java
index 51daf278a4a..84606146f79 100644
--- a/model-evaluation/src/main/java/ai/vespa/models/evaluation/LazyArrayContext.java
+++ b/model-evaluation/src/main/java/ai/vespa/models/evaluation/LazyArrayContext.java
@@ -13,6 +13,7 @@ import com.yahoo.searchlib.rankingexpression.evaluation.Value;
 import com.yahoo.searchlib.rankingexpression.rule.CompositeNode;
 import com.yahoo.searchlib.rankingexpression.rule.ExpressionNode;
 import com.yahoo.searchlib.rankingexpression.rule.ReferenceNode;
+import com.yahoo.tensor.Tensor;
 import com.yahoo.tensor.TensorType;
 
 import java.util.Arrays;
@@ -47,6 +48,14 @@ public final class LazyArrayContext extends Context implements ContextIndex {
     }
 
     /**
+     * Sets the value to use for lookups to existing values which are not set in this context.
+     * The default value that will be returned is NaN
+     */
+    public void setUnboundValue(Tensor value) {
+        indexedBindings.setUnboundValue(value);
+    }
+
+    /**
      * Puts a value by name.
      * The value will be frozen if it isn't already.
      *
@@ -90,10 +99,7 @@ public final class LazyArrayContext extends Context implements ContextIndex {
 
     @Override
     public double getDouble(int index) {
-        double value = get(index).asDouble();
-        if (value == Double.NaN)
-            throw new UnsupportedOperationException("Value at " + index + " has no double representation");
-        return value;
+        return get(index).asDouble();
     }
 
     @Override
@@ -144,11 +150,14 @@ public final class LazyArrayContext extends Context implements ContextIndex {
         /** The names which needs to be bound externally when invoking this (i.e not constant or invocation */
         private final ImmutableSet<String> arguments;
 
-        /** The current values set, pre-converted to doubles */
+        /** The current values set */
         private final Value[] values;
 
-        /** The value to return if not set */
-        private final Value defaultValue;
+        /** The object instance which encodes "no value is set". The actual value of this is never used. */
+        private static final Value missing = new DoubleValue(Double.NaN).freeze();
+
+        /** The value to return for lookups where no value is set */
+        private Value defaultValue;
 
         private IndexedBindings(ImmutableMap<String, Integer> nameToIndex,
                                 Value[] values,
@@ -178,7 +187,7 @@ public final class LazyArrayContext extends Context implements ContextIndex {
             this.arguments = ImmutableSet.copyOf(arguments);
             this.defaultValue = defaultFeatureValue.freeze();
             values = new Value[bindTargets.size()];
-            Arrays.fill(values, this.defaultValue);
+            Arrays.fill(values, missing);
 
             int i = 0;
             ImmutableMap.Builder<String, Integer> nameToIndexBuilder = new ImmutableMap.Builder<>();
@@ -203,6 +212,10 @@ public final class LazyArrayContext extends Context implements ContextIndex {
             }
         }
 
+        private void setUnboundValue(Tensor value) {
+            defaultValue = new TensorValue(value).freeze();
+        }
+
         private void extractBindTargets(ExpressionNode node,
                                         Map<FunctionReference, ExpressionFunction> functions,
                                         Set<String> bindTargets,
@@ -241,7 +254,11 @@ public final class LazyArrayContext extends Context implements ContextIndex {
             return reference.getName().equals("constant") && reference.getArguments().size() == 1;
         }
 
-        Value get(int index) { return values[index]; }
+        Value get(int index) {
+            Value value = values[index];
+            return value == missing ? defaultValue : value;
+        }
+
         void set(int index, Value value) {
             values[index] = value;
         }
diff --git a/model-evaluation/src/test/java/ai/vespa/models/evaluation/ModelsEvaluatorTest.java b/model-evaluation/src/test/java/ai/vespa/models/evaluation/ModelsEvaluatorTest.java
index e8620670dd6..4e31dd89e6a 100644
--- a/model-evaluation/src/test/java/ai/vespa/models/evaluation/ModelsEvaluatorTest.java
+++ b/model-evaluation/src/test/java/ai/vespa/models/evaluation/ModelsEvaluatorTest.java
@@ -7,7 +7,6 @@ import com.yahoo.filedistribution.fileacquirer.MockFileAcquirer;
 import com.yahoo.path.Path;
 import com.yahoo.searchlib.rankingexpression.ExpressionFunction;
 import com.yahoo.searchlib.rankingexpression.RankingExpression;
-import com.yahoo.searchlib.rankingexpression.rule.ReferenceNode;
 import com.yahoo.tensor.Tensor;
 import com.yahoo.tensor.TensorType;
 import com.yahoo.vespa.config.search.RankProfilesConfig;
@@ -19,6 +18,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
 
 /**
  * @author bratseth
@@ -36,6 +36,30 @@ public class ModelsEvaluatorTest {
         assertEquals(32.0, function.evaluate().asDouble(), delta);
     }
 
+    /** Tests a function defined as 4 * (var1 + var2) */
+    @Test
+    public void testSettingDefaultVariableValue() {
+        ModelsEvaluator models = createModels("src/test/resources/config/rankexpression/");
+
+        {
+            FunctionEvaluator function = models.evaluatorOf("macros", "secondphase");
+            assertTrue(Double.isNaN(function.evaluate().asDouble()));
+        }
+
+        {
+            FunctionEvaluator function = models.evaluatorOf("macros", "secondphase");
+            function.setUnboundValue(5);
+            assertEquals(40.0, function.evaluate().asDouble(), delta);
+        }
+
+        {
+            FunctionEvaluator function = models.evaluatorOf("macros", "secondphase");
+            function.setUnboundValue(5);
+            function.bind("match", 3);
+            assertEquals(32.0, function.evaluate().asDouble(), delta);
+        }
+    }
+
     @Test
     public void testBindingValidation() {
         List<ExpressionFunction> functions = new ArrayList<>();