反三角函数asin,acos,atan,atan2的实现，编写手机游戏的数学相关库时，经常会用到。 ,反三角函数asin, acos, atan, atan2 realization, the preparation of mathematics related to mobile phone games library, is often used.

Descr iption Scientific calculator. Allows to perform caclulation with high precicion and implements most populatr mathematical functions: sin, cos, tan, asin, acon, atan, exp, log, sqr, floor and ceil. Also it make it possible to define your ow