need help writing a lisp to calculate slope

hi, i'm still pretty new to lisp writing, so this is a little out of
my league. i am wondering if i can get any help.
what i need is a lisp routine that will allow me to type in both
elevations, select the two points (for a distance) and then it will
create a line of text (preferably mtext) at the midpoint that look
something like: 30 LF @ 3.00%

if anyone is willing to help, it would be greatly appreciated.
thanks in advance

 

I have a '2d grading plan' lisp on my site called "topo" that has various
functions in it. One of them labels the slope between two points, given
existing text or attribute info for the elevation and points picked on
screen for the X and Y. It uses a leader to show the direction, and labels
the midpoint of the leader with text reading "x.xx %" based on preferences
set in the routine.

It's one of my most powerful routines. You are welcome to grab the code and
modify to suit your purposes.