高斯正算和反算，都是自己写的代码，如有不足之处，请见谅-And inverse Gaussian positive operator, are to write their own code, if inadequate, please forgive me

线路设计时可以通过此程序由切线长、曲线偏角等曲线要素反算出曲线半径-Circuit design through this procedure by the tangent length, curve angle elements such as anti-calculated curve radius curve

角度转弧度，弧度转角度， 坐标的正算，坐标的反算(Angle turns radian, radian turns angle, The positive calculation of coordinates and the inverse of coordinates)