说明：  浮点数处理包，提供了很多浮点数处理函数，如比较、取整、截断、转换、计算浮点数点间的距离等，有一定参考价值
(Float package deal, with a lot of floating-point processing function, such as comparison, rounding, truncation, conversion, calculation of floating-point numbers, such as the distance between points, has a certain reference value)