Adding precision test.

Signed-off-by: jzonthemtn <[email protected]>

opensearch-search-quality-evaluation-plugin/src/main/java/org/opensearch/eval/metrics/PrecisionSearchMetric.java

@@ -40,15 +40,15 @@ public String getName() {
     @Override
     public double calculate() {
 
-        int numberOfRelevantItems = 0;
+        double numberOfRelevantItems = 0;
 
         for(final double relevanceScore : relevanceScores) {
             if(relevanceScore >= threshold) {
                 numberOfRelevantItems++;
             }
         }
 
-        return (double) numberOfRelevantItems / (double) k;
+        return numberOfRelevantItems / (double) k;
 
     }
 

opensearch-search-quality-evaluation-plugin/src/test/java/org/opensearch/eval/metrics/NdcgSearchMetricTest.java

@@ -20,9 +20,9 @@ public void testCalculate() {
         final List<Double> relevanceScores = List.of(1.0, 2.0, 3.0, 1.0, 2.0, 3.0, 1.0, 2.0, 3.0, 0.0);
 
         final NdcgSearchMetric ndcgSearchMetric = new NdcgSearchMetric(k, relevanceScores);
-        final double dcg = ndcgSearchMetric.calculate();
+        final double ndcg = ndcgSearchMetric.calculate();
 
-        assertEquals(0.7151195094457645, dcg, 0.0);
+        assertEquals(0.7151195094457645, ndcg, 0.0);
 
     }
 

opensearch-search-quality-evaluation-plugin/src/test/java/org/opensearch/eval/metrics/PrecisionSearchMetricTest.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+package org.opensearch.eval.metrics;
+
+import org.opensearch.test.OpenSearchTestCase;
+
+import java.util.List;
+
+public class PrecisionSearchMetricTest extends OpenSearchTestCase {
+
+    public void testCalculate() {
+
+        final int k = 5;
+        final double threshold = 1.0;
+        final List<Double> relevanceScores = List.of(1.0, 2.0, 3.0, 1.0, 2.0, 3.0, 1.0, 2.0, 3.0, 0.0);
+
+        final PrecisionSearchMetric precisionSearchMetric = new PrecisionSearchMetric(k, threshold, relevanceScores);
+        final double precision = precisionSearchMetric.calculate();
+
+        assertEquals(1.8, precision, 0.0);
+
+    }
+
+}