Lighting Layout : 1-Unit from edge, 2-units in between

Have you ever worked on Electrical drawings, especially "Lighting Layout" drawing?
In a Lighting Layout drawing, the blocks representing the normal light will be placed in a room as ...
one unit from the edges of wall & two units in between them.
This is a common concept.

So a draftsman has to either calculate manually or either place a line touching both walls (towards the LENGTH or WIDTH) and then using AutoCAD builtin command DIVIDE, he can get the required points.
But, Its annoying to use a long procedure of dividing & putting/erasing the POINTS, Hence, I worked to develop a LISP routine.

So this LISP routine is actually ...
A command to DIVIDE a line/pline/arc in equal segments with 1-unit from both ends and 2-units in between segments.

* DIVIDE_ALTERNATE.LSP (2Kb)
This command will DIVIDE a line/pline/arc in equal segments with 1-unit from both ends and 2-units in between segments.

Sequence of command lines for this routine:-

Command: DVD
Pick LINE/PLINE/ARC:
Enter the number of POINTS:

Download : DIVIDE_ALTERNATE.LSP