This command fits a curve between two tangent lines and a known
external secant distance.
It prompts for the P.I. and points on the two tangent lines then the
external distance.
[int on] Pick P.I. of curve: pick
a
point
[nea on] Pick Point on 1st Tangent
Line: pick a point
[nea on] Pick Point on 2nd Tangent
Line: pick a point
External Distance <50.00>: press
Enter
Pulldown Menu Location: Draw > Arc
Keyboard Command: 2tanlex
Prerequisite: Tangent lines should be drawn before execution
File Name: \lsp\2tanlex.lsp