感谢大神！刚才在Matlab上试过了，感觉图像有点像股票走势了，但是为什么用rand（）来做效果更好呢？更像股票数据呢？

感谢大神！刚才在Matlab上试过了，感觉图像有点像股票走势了，但是为什么用rand（）来做效果更好呢？更像股票数据呢？

大神，这是用调整后 mu=0.15  sigma=0.3 lt=15之后Matlab做出来的数据，感觉为啥有点不像股票数据走势图呢？谢大神！！

That's it. This is correct. If you want to make it better, choose a smaller time interval, as small as possible (as long as you do not run out of memory). Another thing is your time horizon is 15 years... try some shorter time horizon like 1 year as I recommended. You usually do not see a 15 years stock graph, that's probably the reason why you don't feel it looks like a stock process.