Using CAD/CAM for three-dimensional linear programming models

A software package has been developed for the Intergraph CAD/CAM system to illustrate three-dimensional linear programming models. The software, called LPVAX, allows a user to enter a linear programming model with three variables and receive a complete solution including sensitivity analysis. The use may then, by menu commands, enter the solution into a graphics file for the CAD/CAM system to convert into graphics displays. The user can display all of the constraints and the objective function in a three-dimensional graph. The solution solid can be viewed and rotated continuously, a key technique for user understanding of the feasible solution space. Constraints can be removed from or added to the display singly or in groups so that any number of the constraints may be displayed immediately. The system is menu-driven for ease of use.