The Place Coordinate System by Three Points command defines a geographical reference that you can use to specify distances for
input, read positions for output, and view orientation of the model. Use this command
instead of the Place Coordinate System when you need to place the coordinate system rotated about the X-, Y-, or Z-axis. The need for a rotated coordinated system can occur when orienting profiles on a hull, for example.
Generally, you create all of your needed design coordinate systems at the beginning of a project. However, you can place design coordinates systems at any time during a project.
The software represents each design coordinate system that you place using a triad showing the X-, Y-, and Z-axes (Ship type coordinate systems) or the north (N), east (E), and elevation (EL) axes (Grids type coordinate systems).