请问这个pow这个参数是啥

[chaofengustc]

请问这个pow这个参数是啥，请问这个代码相对于nips原文里面的算法有什么改变

[sunbelbd]

pow corresponds to the 2 in the denominator in Equation (2).
Usually pow=2 is good enough for most datasets.
We made pow as a tunable parameter for users who would like to obtain even better performance.