public List <Double> getSARLineDatas(List <HSIFutures> list, float step, float maxStep)
{
List <Double> sarList = new List <Double>();
//记录没有没有初始化过
double INIT_VALUE = -100;
//加速因子
double af = 0; //加速因子
//极值
double ep = INIT_VALUE; //极点价
//判断是上涨还是下跌 false：下跌
bool lasttrend = false;
double SAR = 0;
for (int i = 0; i < list.Count() - 1; i++)
{
//上一个周期的sar
double priorSAR = SAR;
HSIFutures item = list[i];
if (lasttrend)
{
//上涨
if (ep == INIT_VALUE || ep < item.GetHigh())
{
//重新初始化值
ep = item.GetHigh(); //当这个周期为上涨，前一个周期的 ep为 最高价
af = Math.Min(af + step, maxStep); //af
}
SAR = priorSAR + af * (ep - priorSAR); //这以周期的的SAR值
double lowestPrior2Lows = Math.Min(list[Math.Max(1, i) - 1].GetLow(), list[i].GetLow());
if (SAR > list[i + 1].GetLow())
{
SAR = ep;
//重新初始化值
af = 0;
ep = INIT_VALUE;
lasttrend = !lasttrend;
}
else if (SAR > lowestPrior2Lows)
{
SAR = lowestPrior2Lows;
}
}
else
{
if (ep == INIT_VALUE || ep > list[i].GetLow())
{
//重新初始化值
ep = list[i].GetLow();
af = Math.Min(af + step, maxStep);
}
SAR = priorSAR + af * (ep - priorSAR);
double highestPrior2Highs = Math.Max(list[Math.Max(1, i) - 1].GetHigh(), list[i].GetHigh());
if (SAR < list[i + 1].GetHigh())
{
SAR = ep;
//重新初始化值
af = 0;
ep = INIT_VALUE;
lasttrend = !lasttrend;
}
else if (SAR < highestPrior2Highs)
{
SAR = highestPrior2Highs;
}
}
sarList.Add(SAR);
}
//确保和 传入的list size一致，
int size = list.Count() - sarList.Count();
for (int i = 0; i < size; i++)
{
sarList.Insert(0, sarList[i]);
}
//返回了一个包含所有SAR值的数组
return(sarList);
}
