RegressionCalculator.java
/*
* Copyright (c) 2016, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
*
* WSO2 Inc. 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.wso2.extension.siddhi.execution.timeseries.linreg;
/**
* Abstract class for regression calculation.
*/
public abstract class RegressionCalculator {
protected double confidenceInterval = 0.95;
protected int eventCount = 0;
protected int xParameterCount = 0;
protected int batchSize = 1000000000;
protected int incCounter = 0;
protected int calcInterval;
public RegressionCalculator(int paramCount, int calcInt, int limit, double ci) {
confidenceInterval = ci;
batchSize = limit;
xParameterCount = paramCount - 1;
calcInterval = calcInt;
}
protected abstract void addEvent(Object[] data);
protected abstract void removeEvent();
protected abstract Object[] processData();
public Object[] calculateLinearRegression(Object[] data) {
addEvent(data);
// removing oldest events in order to maintain batchsize
if (eventCount > batchSize) {
eventCount--;
removeEvent();
}
// processing at a user specified calculation interval
if (incCounter % calcInterval != 0) {
return null;
}
return processData();
}
}