Given a constant c this function returns x if x is less than c and sign(x)*(c*log(abs(x)/c) + c) if its not. Notice this is a continuous odd ( f(-x)=-f(x) ) function with continuous first derivative. The main purpose is to perform log
鉴于恒定c这个函数返回x如果x是c和sign(x)*(c*log(abs(x)/c) + c)如果它不少。请注意这是一个连续的奇数(F(-X)= F(X))函数的一阶导数连续。其主要目的是执行log
用法----------Usage----------
hlog(x, constant=1)
参数----------Arguments----------
参数:x
a number.
一个数字。
参数:constant
the constant c (see description).
常数c(见说明)。
Details
详情----------Details----------
If constant is less than or equal to 0 log(x) is returned for all x. If constant is infinity x is returned for all x.
如果constant的小于或等于0log(x)所有的x返回。如果constant的无穷x返回所有的x。