SOLR-11400: Add logNormalDistribution Stream Evaluator

solr/core/src/java/org/apache/solr/handler/StreamHandler.java

@@ -29,6 +29,7 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 
+import org.apache.commons.math3.distribution.LogNormalDistribution;
 import org.apache.solr.client.solrj.io.ModelCache;
 import org.apache.solr.client.solrj.io.SolrClientCache;
 import org.apache.solr.client.solrj.io.Tuple;
@@ -303,6 +304,8 @@ public class StreamHandler extends RequestHandlerBase implements SolrCoreAware,
         .withFunctionName("constantDistribution", ConstantDistributionEvaluator.class)
         .withFunctionName("weibullDistribution", WeibullDistributionEvaluator.class)
         .withFunctionName("mean", MeanEvaluator.class)
+        .withFunctionName("mode", ModeEvaluator.class)
+        .withFunctionName("logNormalDistribution", LogNormalDistributionEvaluator.class)
 
         // Boolean Stream Evaluators
 

solr/solrj/src/java/org/apache/solr/client/solrj/io/eval/LogNormalDistributionEvaluator.java

@@ -0,0 +1,48 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.solr.client.solrj.io.eval;
+
+import java.io.IOException;
+import java.util.Locale;
+
+import org.apache.commons.math3.distribution.LogNormalDistribution;
+import org.apache.solr.client.solrj.io.stream.expr.StreamExpression;
+import org.apache.solr.client.solrj.io.stream.expr.StreamFactory;
+
+public class LogNormalDistributionEvaluator extends RecursiveNumericEvaluator implements TwoValueWorker {
+
+  private static final long serialVersionUID = 1;
+
+  public LogNormalDistributionEvaluator(StreamExpression expression, StreamFactory factory) throws IOException {
+    super(expression, factory);
+  }
+
+  @Override
+  public Object doWork(Object first, Object second) throws IOException{
+    if(null == first){
+      throw new IOException(String.format(Locale.ROOT,"Invalid expression %s - null found for the first value",toExpression(constructingFactory)));
+    }
+    if(null == second){
+      throw new IOException(String.format(Locale.ROOT,"Invalid expression %s - null found for the second value",toExpression(constructingFactory)));
+    }
+
+    Number shape = (Number)first;
+    Number scale = (Number)second;
+
+    return new LogNormalDistribution(scale.doubleValue(), shape.doubleValue());
+  }
+}

solr/solrj/src/java/org/apache/solr/client/solrj/io/eval/ModeEvaluator.java

@@ -0,0 +1,64 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.solr.client.solrj.io.eval;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Locale;
+
+import org.apache.solr.client.solrj.io.stream.expr.StreamExpression;
+import org.apache.solr.client.solrj.io.stream.expr.StreamFactory;
+import org.apache.commons.math3.stat.StatUtils;
+
+
+public class ModeEvaluator extends RecursiveObjectEvaluator implements OneValueWorker {
+  protected static final long serialVersionUID = 1L;
+
+  public ModeEvaluator(StreamExpression expression, StreamFactory factory) throws IOException{
+    super(expression, factory);
+
+    if(1 != containedEvaluators.size()){
+      throw new IOException(String.format(Locale.ROOT,"Invalid expression %s - expecting exactly 1 value but found %d",expression,containedEvaluators.size()));
+    }
+  }
+
+  @Override
+  public Object doWork(Object value) throws IOException{
+    if(null == value){
+      throw new IOException(String.format(Locale.ROOT, "Unable to find %s(...) because the value is null", constructingFactory.getFunctionName(getClass())));
+    }
+    else if(value instanceof List){
+      List<Number> c = (List<Number>) value;
+      double[] data = new double[c.size()];
+      for(int i=0; i< c.size(); i++) {
+        data[i] = c.get(i).doubleValue();
+      }
+
+      double[] mode = StatUtils.mode(data);
+      List<Number> l = new ArrayList();
+      for(double d : mode) {
+        l.add(d);
+      }
+
+      return l;
+    }
+    else{
+      throw new IOException(String.format(Locale.ROOT, "Unable to find %s(...) because the value is not a collection, instead a %s was found", constructingFactory.getFunctionName(getClass()), value.getClass().getSimpleName()));
+    }
+  }
+}

solr/solrj/src/test/org/apache/solr/client/solrj/io/stream/StreamExpressionTest.java

@@ -6555,11 +6555,13 @@ public class StreamExpressionTest extends SolrCloudTestCase {
   @Test
   public void testWeibullDistribution() throws Exception {
     String cexpr = "let(echo=true, " +
-                       "a=percentile(sample(weibullDistribution(1, 10),5000), 50), " +
+                       "a=describe(sample(weibullDistribution(.1, 10),10000)), " +
-                       "b=percentile(sample(weibullDistribution(1, 50),5000), 50), " +
+                       "b=describe(sample(weibullDistribution(.5, 10),10000)), " +
-                       "c=percentile(sample(weibullDistribution(1, 100),5000), 50)," +
+                       "c=describe(sample(weibullDistribution(1, 10),10000))," +
-                       "d=percentile(sample(weibullDistribution(4, 10),5000), 50)," +
+                       "d=describe(sample(weibullDistribution(6, 10),10000))," +
-                       "e=percentile(sample(weibullDistribution(8, 10),5000), 50))";
+                       "e=mean(sample(weibullDistribution(1, 10),10000))," +
+                       "f=mean(sample(weibullDistribution(1, 20),10000))," +
+                       "g=mean(sample(weibullDistribution(1, 30),10000)))";
 
     ModifiableSolrParams paramsLoc = new ModifiableSolrParams();
     paramsLoc.set("expr", cexpr);
@@ -6570,17 +6572,68 @@ public class StreamExpressionTest extends SolrCloudTestCase {
     solrStream.setStreamContext(context);
     List<Tuple> tuples = getTuples(solrStream);
     assertTrue(tuples.size() == 1);
-    Number a = (Number)tuples.get(0).get("a");
+    Map a = (Map)tuples.get(0).get("a");
-    Number b = (Number)tuples.get(0).get("b");
+    Map b = (Map)tuples.get(0).get("b");
-    Number c = (Number)tuples.get(0).get("c");
+    Map c = (Map)tuples.get(0).get("c");
-    Number d = (Number)tuples.get(0).get("d");
+    Map d = (Map)tuples.get(0).get("d");
+
+    Number sa = (Number)a.get("skewness");
+    Number sb = (Number)b.get("skewness");
+    Number sc = (Number)c.get("skewness");
+    Number sd = (Number)d.get("skewness");
+
+    //Test shape change
+    assertTrue(sa.doubleValue() > sb.doubleValue());
+    assertTrue(sb.doubleValue() > sc.doubleValue());
+    assertTrue(sc.doubleValue() > sd.doubleValue());
+    assertTrue(sd.doubleValue() < 0.0);
+
+    //Test scale change
+
     Number e = (Number)tuples.get(0).get("e");
-    assertTrue(a.doubleValue() < b.doubleValue());
+    Number f = (Number)tuples.get(0).get("f");
-    assertTrue(b.doubleValue() < c.doubleValue());
+    Number g = (Number)tuples.get(0).get("g");
-    assertTrue(a.doubleValue() < d.doubleValue());
+
-    assertTrue(d.doubleValue() < e.doubleValue());
+    assertTrue(e.doubleValue() < f.doubleValue());
+    assertTrue(f.doubleValue() < g.doubleValue());
   }
 
+  @Test
+  public void testLogNormalDistribution() throws Exception {
+    String cexpr = "let(echo=true, " +
+        "a=describe(sample(logNormalDistribution(.1, 0),10000)), " +
+        "b=describe(sample(logNormalDistribution(.3, 0),10000)), " +
+        "c=describe(sample(logNormalDistribution(.6, 0),10000))," +
+        "d=mean(sample(logNormalDistribution(.3, 0),10000)), " +
+        "e=mean(sample(logNormalDistribution(.3, 2),10000)), " +
+        ")";
+
+    ModifiableSolrParams paramsLoc = new ModifiableSolrParams();
+    paramsLoc.set("expr", cexpr);
+    paramsLoc.set("qt", "/stream");
+    String url = cluster.getJettySolrRunners().get(0).getBaseUrl().toString()+"/"+COLLECTIONORALIAS;
+    TupleStream solrStream = new SolrStream(url, paramsLoc);
+    StreamContext context = new StreamContext();
+    solrStream.setStreamContext(context);
+    List<Tuple> tuples = getTuples(solrStream);
+    assertTrue(tuples.size() == 1);
+    Map a = (Map)tuples.get(0).get("a");
+    Map b = (Map)tuples.get(0).get("b");
+    Map c = (Map)tuples.get(0).get("c");
+
+    Number sa = (Number)a.get("skewness");
+    Number sb = (Number)b.get("skewness");
+    Number sc = (Number)c.get("skewness");
+
+    assertTrue(sa.doubleValue() < sb.doubleValue());
+    assertTrue(sb.doubleValue() < sc.doubleValue());
+
+    Number d = (Number)tuples.get(0).get("d");
+    Number e = (Number)tuples.get(0).get("e");
+
+    assertTrue(d.doubleValue() < e.doubleValue());
+
+  }
 
   @Test
   public void testMean() throws Exception {