最近做的项目需要实现EMA和MACD，但苦于网上没有具体的实现算法。所以自己尝试着编写了一套。

已经和通达信等主流股票分析软件核对过结果，并将其开源放在GitHub上，含Junit 测试用例。

GitHub地址：https://github.com/wizardbyron/finance-indicators

/**

* Calculate EMA,

*

* @param list

* :Price list to calculate，the first at head, the last at tail.

* @return

*/

public static final Double getEXPMA(final List list, final int number) {

// 开始计算EMA值，

Double k = 2.0 / (number + 1.0);// 计算出序数

Double ema = list.get(0);// 第一天ema等于当天收盘价

for (int i = 1; i < list.size(); i++) {

// 第二天以后，当天收盘 收盘价乘以系数再加上昨天EMA乘以系数-1

ema = list.get(i) * k + ema * (1 - k);

}

return ema;

}

/**

* calculate MACD values

*

* @param list

* :Price list to calculate，the first at head, the last at tail.

* @param shortPeriod

* :the short period value.

* @param longPeriod

* :the long period value.

* @param midPeriod

* :the mid period value.

* @return

*/

public static final HashMap getMACD(final List list, final int shortPeriod, final int longPeriod, int midPeriod) {

HashMap macdData = new HashMap();

List diffList = new ArrayList();

Double shortEMA = 0.0;

Double longEMA = 0.0;

Double dif = 0.0;

Double dea = 0.0;

for (int i = list.size() - 1; i >= 0; i--) {

List sublist = list.subList(0, list.size() - i);

shortEMA = Indicators.getEXPMA(sublist, shortPeriod);

longEMA = Indicators.getEXPMA(sublist, longPeriod);

dif = shortEMA - longEMA;

diffList.add(dif);

}

dea = Indicators.getEXPMA(diffList, midPeriod);

macdData.put("DIF", dif);

macdData.put("DEA", dea);

macdData.put("MACD", (dif - dea) * 2);

return macdData;

}