替代数据生成算法。包括常用的随机相位法(shuffle.m and surrogate.m)，周期随机相位法(cycleshuffle.m)和PPS算法(pps.m and findrho.m).-Surrogate data algorithms, including the usual approaches (shuffle.m and surrogate.m), the cycle shuffle version (cycleshuffle.m) and the PPS algorithm