Interestingly, there is a point of discontinuity around zero.
有趣的是，有一个点的不连续性在零附近。
2
In transient state signal and in image analysis, the point of discontinuity often is one of important characteristics, they are located the edge of the important structure frequently.
在瞬态信号与图像的分析中，突变点往往是重要的特征之一，它们常常位于重要结构的边缘部分。
3
This paper gives some properties of several special function discontinuitypoint and the first kind discontinuitypoint of ordinary real function. and points out their ap-plicaion in actual problems.