Hi Joe

Just noticed your comment re the catenary sag. Adding this feature to your software will make it exceptional.

The formula is widely cited the Wiki in this case is a good place to start.
https://en.wikipedia.org/wiki/Catenary#Equation

Once your measurement table is filled with points and the user has input a length The catenary sag allowance at each point can be added to the table. The weight of the wire and the tension applied to it need to be added, they do not change so can be stored constants.

Regards
John