度、弧度、百分度、角分、角秒等角度單位轉換
1 弧度 = 1rad
1 度 = 0.017453286279273523rad
1 百分度 = 0.015707957651346173rad
1 rad = 57.295800 °
1 ° = 1.111112 grad
1 grad = 54.000177 arcmin
1 arcmin = 60.000013 arcsec