DifferenceIndicator.java

/**
 * The MIT License (MIT)
 *
 * Copyright (c) 2014-2017 Marc de Verdelhan & respective authors (see AUTHORS)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
package eu.verdelhan.ta4j.indicators.simple;

import eu.verdelhan.ta4j.Indicator;
import eu.verdelhan.ta4j.Decimal;
import eu.verdelhan.ta4j.indicators.CachedIndicator;

/**
 * Difference indicator.
 * <p>
 * I.e.: first - second
 */
public class DifferenceIndicator extends CachedIndicator<Decimal> {

    private Indicator<Decimal> first;
    
    private Indicator<Decimal> second;
    
    /**
     * Constructor.
     * (first minus second)
     * @param first the first indicator
     * @param second the second indicator
     */
    public DifferenceIndicator(Indicator<Decimal> first, Indicator<Decimal> second) {
        // TODO: check if first series is equal to second one
        super(first);
        this.first = first;
        this.second = second;
    }

    @Override
    protected Decimal calculate(int index) {
        return first.getValue(index).minus(second.getValue(index));
    }
}