Comparison functions on tensors

8 files changed, 40 insertions, 60 deletions

diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/DoubleCompatibleValue.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/DoubleCompatibleValue.java
index 2bae382d5bd..f8dcd8a6127 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/DoubleCompatibleValue.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/DoubleCompatibleValue.java
@@ -39,8 +39,8 @@ public abstract class DoubleCompatibleValue extends Value {
     }
 
     @Override
-    public boolean compare(TruthOperator operator, Value value) {
-        return operator.evaluate(asDouble(), value.asDouble());
+    public Value compare(TruthOperator operator, Value value) {
+        return new BooleanValue(operator.evaluate(asDouble(), value.asDouble()));
     }
 
     @Override
diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/DoubleValue.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/DoubleValue.java
index 1cd65c3133a..35c210da0c0 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/DoubleValue.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/DoubleValue.java
@@ -98,16 +98,6 @@ public final class DoubleValue extends DoubleCompatibleValue {
     }
 
     @Override
-    public boolean compare(TruthOperator operator, Value value) {
-        try {
-            return operator.evaluate(this.value, value.asDouble());
-        }
-        catch (UnsupportedOperationException e) {
-            throw unsupported("comparison",value);
-        }
-    }
-
-    @Override
     public Value function(Function function, Value value) {
         // use the tensor implementation of max and min if the argument is a tensor
         if ( (function.equals(Function.min) || function.equals(Function.max)) && value instanceof TensorValue)
diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/StringValue.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/StringValue.java
index b2dc5e27b91..9d0f0b692c4 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/StringValue.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/StringValue.java
@@ -68,10 +68,10 @@ public class StringValue extends Value {
     }
 
     @Override
-    public boolean compare(TruthOperator operator, Value value) {
+    public Value compare(TruthOperator operator, Value value) {
         if (operator.equals(TruthOperator.EQUAL))
-            return this.equals(value);
-        throw new UnsupportedOperationException("String values ('" + value + "') cannot be compared except with '='");
+            return new BooleanValue(this.equals(value));
+        throw new UnsupportedOperationException("String values ('" + value + "') cannot be compared except with '=='");
     }
 
     @Override
diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/TensorValue.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/TensorValue.java
index dc422f2c8da..b1f4a7b20ca 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/TensorValue.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/TensorValue.java
@@ -89,30 +89,6 @@ public class TensorValue extends Value {
             return new TensorValue(value.map((value) -> value / argument.asDouble()));
     }
 
-    public Value min(Value argument) {
-        return new TensorValue(value.min(asTensor(argument, "min")));
-    }
-
-    public Value max(Value argument) {
-        return new TensorValue(value.max(asTensor(argument, "max")));
-    }
-
-    public Value atan2(Value argument) {
-        return new TensorValue(value.atan2(asTensor(argument, "atan2")));
-    }
-
-    public Value equal(Value argument) {
-        return new TensorValue(value.equal(asTensor(argument, "equal")));
-    }
-
-    public Value sum(String dimension) {
-        return new TensorValue(value.sum(Collections.singletonList(dimension)));
-    }
-
-    public Value sum() {
-        return new TensorValue(value.sum(Collections.emptyList()));
-    }
-
     private Tensor asTensor(Value value, String operationName) {
         if ( ! (value instanceof TensorValue))
             throw new UnsupportedOperationException("Could not perform " + operationName +
@@ -127,22 +103,37 @@ public class TensorValue extends Value {
     }
 
     @Override
-    public boolean compare(TruthOperator operator, Value value) {
-        throw new UnsupportedOperationException("A tensor cannot be compared with any value");
+    public Value compare(TruthOperator operator, Value argument) {
+        return new TensorValue(compareTensor(operator, asTensor(argument, operator.toString())));
+    }
+    
+    private Tensor compareTensor(TruthOperator operator, Tensor argument) {
+        switch (operator) {
+            case LARGER: return value.larger(argument);
+            case LARGEREQUAL: return value.largerOrEqual(argument);
+            case SMALLER: return value.smaller(argument);
+            case SMALLEREQUAL: return value.smallerOrEqual(argument);
+            case EQUAL: return value.equal(argument);
+            case NOTEQUAL: return value.notEqual(argument);
+            default: throw new UnsupportedOperationException("Tensors cannot be compared with " + operator);
+        }
     }
 
     @Override
-    public Value function(Function function, Value argument) {
-        if (function.equals(Function.min) && argument instanceof TensorValue)
-            return min(argument);
-        else if (function.equals(Function.max) && argument instanceof TensorValue)
-            return max(argument);
-        else if (function.equals(Function.atan2) && argument instanceof TensorValue)
-            return atan2(argument);
-        else if (function.equals(Function.equal) && argument instanceof TensorValue)
-            return equal(argument);
+    public Value function(Function function, Value arg) {
+        if (arg instanceof TensorValue)
+            return new TensorValue(functionOnTensor(function, asTensor(arg, function.toString())));
         else
-            return new TensorValue(value.map((value) -> function.evaluate(value, argument.asDouble())));
+            return new TensorValue(value.map((value) -> function.evaluate(value, arg.asDouble())));
+    }
+        
+    private Tensor functionOnTensor(Function function, Tensor argument) {
+        switch (function) {
+            case min: return value.min(argument);
+            case max: return value.max(argument);
+            case atan2: return value.atan2(argument);
+            default: throw new UnsupportedOperationException("Cannot combine two tensors using " + function);
+        }
     }
 
     @Override
diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/Value.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/Value.java
index 142cd650ee8..76daeccc5e0 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/Value.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/evaluation/Value.java
@@ -43,7 +43,7 @@ public abstract class Value {
     public abstract Value divide(Value value);
 
     /** Perform the comparison specified by the operator between this value and the given value */
-    public abstract boolean compare(TruthOperator operator,Value value);
+    public abstract Value compare(TruthOperator operator, Value value);
 
     /** Perform the given binary function on this value and the given value */
     public abstract Value function(Function function,Value value);
diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/ComparisonNode.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/ComparisonNode.java
index 882d16ebc1c..af05acb365a 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/ComparisonNode.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/ComparisonNode.java
@@ -8,10 +8,9 @@ import com.yahoo.searchlib.rankingexpression.evaluation.Value;
 import java.util.*;
 
 /**
- * A node which returns true or false depending on the outcome of a comparison.
+ * A node which returns the outcome of a comparison.
  *
  * @author bratseth
- * @since  5.1.21
  */
 public class ComparisonNode extends BooleanNode {
 
@@ -48,9 +47,9 @@ public class ComparisonNode extends BooleanNode {
 
     @Override
     public Value evaluate(Context context) {
-        Value leftValue=leftCondition.evaluate(context);
-        Value rightValue=rightCondition.evaluate(context);
-        return new BooleanValue(leftValue.compare(operator,rightValue));
+        Value leftValue = leftCondition.evaluate(context);
+        Value rightValue = rightCondition.evaluate(context);
+        return leftValue.compare(operator,rightValue);
     }
 
     @Override
diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/Function.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/Function.java
index b8e48dc2f05..cbea2ad627e 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/Function.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/Function.java
@@ -43,8 +43,7 @@ public enum Function implements Serializable {
     max(2)    { public double evaluate(double x, double y) { return max(x,y); } },
     min(2)    { public double evaluate(double x, double y) { return min(x,y); } },
     mod(2)    { public double evaluate(double x, double y) { return x % y; } },
-    pow(2)    { public double evaluate(double x, double y) { return pow(x,y); } },
-    equal(2)  { public double evaluate(double x, double y) { return x==y ? 1.0 : 0.0; } };
+    pow(2)    { public double evaluate(double x, double y) { return pow(x,y); } };
 
     private final int arity;
 
diff --git a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/TruthOperator.java b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/TruthOperator.java
index 60fe19f909f..932975f3b63 100644
--- a/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/TruthOperator.java
+++ b/searchlib/src/main/java/com/yahoo/searchlib/rankingexpression/rule/TruthOperator.java
@@ -15,7 +15,8 @@ public enum TruthOperator  implements Serializable {
     EQUAL("==")  { public boolean evaluate(double x, double y) { return x==y; } },
     APPROX_EQUAL("~=") { public boolean evaluate(double x, double y) { return approxEqual(x,y); } },
     LARGER(">")   { public boolean evaluate(double x, double y) { return x>y; } },
-    LARGEREQUAL(">=")  { public boolean evaluate(double x, double y) { return x>=y; } };
+    LARGEREQUAL(">=")  { public boolean evaluate(double x, double y) { return x>=y; } },
+    NOTEQUAL("!=")  { public boolean evaluate(double x, double y) { return x!=y; } };
 
     private final String operatorString;