Introduction - If you have any usage issues, please Google them yourself
Including some space algorithms, such as calculating the distance between the two coordinates to determine whether the same two coordinates to calculate cross product, point multiplication calculation to determine whether point p on line l above the calculation point to point op for bp counterclockwise rotation center dAlpha (units : radian) after the location where the coordinates of points, calculated on the specified radius of a round angle specified chord length, calculated from the starting point coordinates and end coordinates of the line constitutes a specified distance and specified direction of the vertical space coordinate algorithm