| /* |
| * 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.sysds.runtime.functionobjects; |
| |
| import org.apache.sysds.runtime.instructions.cp.Data; |
| import org.apache.sysds.runtime.instructions.cp.KahanObject; |
| |
| |
| public class Mean extends ValueFunction |
| { |
| private static final long serialVersionUID = 1967222020396371269L; |
| |
| private static Mean singleObj = null; |
| |
| private KahanPlus _plus = null; |
| |
| private Mean() { |
| _plus = KahanPlus.getKahanPlusFnObject(); |
| } |
| |
| public static Mean getMeanFnObject() { |
| if ( singleObj == null ) |
| singleObj = new Mean(); |
| return singleObj; |
| } |
| |
| @Override |
| public Data execute(Data in1, double in2, double count) { |
| KahanObject kahanObj=(KahanObject)in1; |
| double delta = (in2-kahanObj._sum)/count; |
| _plus.execute(in1, delta); |
| return kahanObj; |
| } |
| |
| /** |
| * Simplified version of execute(Data in1, double in2) |
| * without exception handling and casts. |
| * |
| * @param in1 Kahan object input |
| * @param in2 double input |
| * @param count the count to divide by |
| */ |
| public void execute2(KahanObject in1, double in2, double count) |
| { |
| double delta = (in2-in1._sum)/count; |
| _plus.execute2(in1, delta); |
| } |
| } |