关于CDF图像的问题

问题如下：

How are quantile functions related to the CDF? When X is a continuous random variable, when does this relationship not hold?

解释：

The quantile function is the inverse of the CDF function.

That is, if $u = F_X(x)$ returns the CDF value of X, then $q = F_X^{-1}(u)$ is the quantile function.

The CDF function is not invertible if there are regions where there is no probability. This corresponds to a jump in the CDF.