Fixed a bug in sigmoid(null). PLT-4718

scripts/ddl/define-all-as-permanent.hive

@@ -454,7 +454,8 @@ CREATE FUNCTION to_ordered_map as 'hivemall.tools.map.UDAFToOrderedMap' USING JA
 ---------------------
 
 DROP FUNCTION IF EXISTS sigmoid;
-CREATE FUNCTION sigmoid as 'hivemall.tools.math.SigmodUDF' USING JAR '${hivemall_jar}';
+CREATE FUNCTION sigmoid as 'hivemall.tools.math.SigmoidGenericUDF' USING JAR '${hivemall_jar}';
+-- CREATE FUNCTION sigmoid as 'hivemall.tools.math.SigmoidUDF' USING JAR '${hivemall_jar}';
 
 ----------------------
 -- mapred functions --

scripts/ddl/define-all.hive

@@ -450,7 +450,8 @@ create temporary function to_ordered_map as 'hivemall.tools.map.UDAFToOrderedMap
 ---------------------
 
 drop temporary function sigmoid;
-create temporary function sigmoid as 'hivemall.tools.math.SigmodUDF';
+create temporary function sigmoid as 'hivemall.tools.math.SigmoidGenericUDF';
+-- create temporary function sigmoid as 'hivemall.tools.math.SigmoidUDF';
 
 ----------------------
 -- mapred functions --

src/main/java/hivemall/tools/math/SigmoidGenericUDF.java

@@ -0,0 +1,76 @@
+/*
+ * Hivemall: Hive scalable Machine Learning Library
+ *
+ * Copyright (C) 2015 Makoto YUI
+ * Copyright (C) 2013-2015 National Institute of Advanced Industrial Science and Technology (AIST)
+ *
+ * Licensed 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 hivemall.tools.math;
+
+import hivemall.utils.hadoop.HiveUtils;
+import hivemall.utils.math.MathUtils;
+
+import java.util.Arrays;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+import org.apache.hadoop.hive.ql.exec.Description;
+import org.apache.hadoop.hive.ql.exec.UDFArgumentException;
+import org.apache.hadoop.hive.ql.metadata.HiveException;
+import org.apache.hadoop.hive.ql.udf.UDFType;
+import org.apache.hadoop.hive.ql.udf.generic.GenericUDF;
+import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
+import org.apache.hadoop.hive.serde2.objectinspector.PrimitiveObjectInspector;
+import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory;
+import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorUtils;
+import org.apache.hadoop.io.FloatWritable;
+
+@Description(name = "sigmoid", value = "_FUNC_(x) - Returns 1.0 / (1.0 + exp(-x))")
+@UDFType(deterministic = true, stateful = false)
+public final class SigmoidGenericUDF extends GenericUDF {
+
+    private PrimitiveObjectInspector argOI;
+
+    @Override
+    public ObjectInspector initialize(@Nonnull ObjectInspector[] argOIs)
+            throws UDFArgumentException {
+        if(argOIs.length != 1) {
+            throw new UDFArgumentException("_FUNC_ takes 1 argument");
+        }
+        this.argOI = HiveUtils.asDoubleCompatibleOI(argOIs[0]);
+        return PrimitiveObjectInspectorFactory.writableFloatObjectInspector;
+    }
+
+    @Nullable
+    @Override
+    public FloatWritable evaluate(@Nonnull DeferredObject[] arguments) throws HiveException {
+        assert (arguments.length == 1) : "sigmoid takes 1 argument: " + arguments.length;
+        DeferredObject arg0 = arguments[0];
+        assert (arg0 != null);
+        Object obj0 = arg0.get();
+        if(obj0 == null) {
+            return null;
+        }
+        double x = PrimitiveObjectInspectorUtils.getDouble(obj0, argOI);
+        float v = (float) MathUtils.sigmoid(x);
+        return new FloatWritable(v);
+    }
+
+    @Override
+    public String getDisplayString(String[] children) {
+        return "sigmoid(" + Arrays.toString(children) + ')';
+    }
+
+}

src/main/java/hivemall/tools/math/SigmodUDF.java → src/main/java/hivemall/tools/math/SigmoidUDF.java

@@ -25,9 +25,10 @@
 import org.apache.hadoop.hive.ql.udf.UDFType;
 import org.apache.hadoop.io.FloatWritable;
 
+@Deprecated
 @Description(name = "sigmoid", value = "_FUNC_(x) - Returns 1.0 / (1.0 + exp(-x))")
 @UDFType(deterministic = true, stateful = false)
-public final class SigmodUDF extends UDF {
+public final class SigmoidUDF extends UDF {
 
     public FloatWritable evaluate(float x) {
         return val(1.0f / (1.0f + (float) Math.exp(-x)));