2014-04-05 Kun Ren
As we know, a Brownian motion is usually formulated as $$dx_t = \mu\,dt+\sigma\,dW_t$$ which is the continuous case of a random walk. In some cases, it is quite convenient to use this formulation to describe the characteristic of asset prices due to its highly unpredictable behavior. 继续阅读 »
2015-11-30 Alex Sun
8. series/parallel/parallelLimit async.eachOfSeries(arr, iterator, callback)是对arr中的每一项,调用iterator函数,最终调用callback。也就是说,所有的异步任务都是同一种类型,只是传入的参数不同。例如对于一个目录下的所有文件,统计每个文件的size。 继续阅读 »