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From SofTutor for MicroStation 2D - Part 1: Rectangular Coordinates And Commands
Topics & Keywords covered in this video are:

Polar Coordinates - Placing An Element DI Key-in Design Plane Draw Relative
Relative Coordinates - Placing An Element XYZ Key-in Delta Design Plane Drawing
Absolute Coordinates - Placing An Element XYZ Key-in Design Plane Drawing
Part 1: Rectangular Coordinates And Commands DI Key-in Design Plane Draw Relative
Polar View Coordinates - Placing An Element DX Key-in Design Plane Draw Relative