Including the commonly used functions (trigonometric, inverse trigonometric func...

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包括常用的函数（三角函数、反三角函数、双曲三角函数、绝对值.......），甚至是 一些复杂无比的表达式也能计算，如：ln e + rnd(2) + 3(2)4 * (log(tan (itan 1))) 等。值得一提 的是，它还有函数绘图、数据统计和自定义常数等功能。另外，程序经过我汉化（仅在界面上），更易 懂。-Including the commonly used functions (trigonometric, inverse trigonometric functions, hyperbolic trigonometric functions, absolute value .......), even extremely complex expressions can be calculated as: ln e+ rnd (2)+ 3 (2) 4* (log (tan (itan 1))) and so on. It is worth mentioning that it also has the function mapping, data statistics, and custom constants and other functions. In addition, the program after I finished (only at the interface), more understandable.