randn

代码说明：

  产生各类随机数的一个C++类，包括均匀分布，泊松分布，指数分布，瑞利分布，伯努利分布，高斯分布等；相应的参数可以自己设置。(A C++ class that produces various types of random numbers, including uniform distribution, Poisson distribution, exponential distribution, Rayleigh distribution, Bernoulli distribution, Gaussian distribution, etc.; the corresponding parameters can be set by themselves.)