In the coordinate system, the numbers of "X" axis and "Y" axis represent the abscissa and ordinate of each point on the plane, that is, as long as an "X" and "Y" are determined, a point on the coordinate system plane can be determined.

Longitude and latitude should be in spherical coordinate system.

The engineering coordinate system is opposite to the mathematical coordinate system. Generally, the north direction is the X direction of the project and the east direction is the Y direction of the project, so the north coordinate number represents the X coordinate, the east coordinate number represents the Y coordinate and Z represents the elevation.