USE OF GRAPH

Graphs are regularly used to drive geometry in a Variable Section Sweep. More specifically, a graph typically controls a dimension which continuously changes as the sweeping section follows the primary driving trajectory of the Variable Section Sweep. In this context a graph is used in conjunction with the specific parameter trajpar which varies continuously from 0 to 1 as the section follows the primary trajectory. That is, it has value 0 at the start point of the Sweep, value 0.5 half way along the trajectory, and value 1.0 at the end. Usually this arbitrary 0-to-1 range is multiplied by some factor appropriate to the particular geometry. The graph itself is invoked using the specific EVALGRAPH call followed by the name of the graph in quotes, comma-delimited, then linked to the factor-multiplied trajpar parameter. A graph can be very powerful and useful because you can sketch a varying graphical relationship using lines, arcs, and splines that would be impossible to capture in a simple equation. This is an overview. For more detail look at Variable Section Sweep articles in the Help files and on the PTC website. You should find examples there. Good luck! These can be a lot of fun. David