Unique Deviation Report

[CADTACULAR]

I'm trying to figure out if there is a way to create a deviation report based on a grid.  So Say I import points from a plane. Set a zero. Then overlay a gird to the points.  Optimally I would be able to automaticly have the closest point to each intersection picked and noted with a deviation from my zero. Or I would have to go through manually and pick the points closest to the grid.

What is the best way to do this?

More details:

This would be based off of scan data points

I'll add more as needed or asked....

[hencoop]

You might use your grid spacing to establish values for a series of selection windows specified as a set of X-Y coordinate pairs that bound the intersections and then step through your grid making a selection set with a crossing window that has each intersection at its center in turn.  You will need to increment your selection window coordinates by the grid spacing and then reset X or Y as you process subsequent rows or columns respectively.  The crossing window coordinates should probably be one grid square apart in each direction but land on midpoints between the intersections.

e.g.

(SSGET "C" [pt-list = list of points describing your crossing window] '((0 . "POINT")))

If any points are actually selected for a given intersection, examine each one to get their (DISTANCE [point-coordinate] [intersection coordinate]).  If there is only one then that is the nearest for that intersection.  If there are more, take the one with the minimum distance from the intersection and store it as the result for that intersection.

If the points are "AECC_COGO_POINTS" then there is a bit more effort necessary to extract the coordinates for them but it can be done.

The rest is just tabulating your results to suit your requirements