How can I create Boundaries/Polygons from Points for use in PROC SGMAP choromap statement

[tgrandchamp]

I am trying to create a dataset of geographic (Lat& Long based) polygon boundaries similar to the mapsgfk.us_counties data set. With the goal of displaying polygons of the resulting polygons using a choromap statement in PROC SGMAP.

The data I have to start with are individual latitude and longitude variables for data points within a given polygon. How can i use these individual Lat & Long datapoints to generate the boundry information necessary to use the choromap statement to create a polygon that overlays the area containing the individual data points.

Basically I am trying to take the plot data from the top image and create the boundry polygon on the bottom image:

[ChrisNZ]

That's a non-trivial modelling computation you are seeking here, imho.

Nothing that can be answered here unless someone already did the same thing and is ready to share (always worth trying...).

The way I would approach this is have the coordinates of the streets, see which street segments are INSIDE the zone, and make the boundary pass between INSIDE streets and the closest OUTSIDE streets.

Not trivial.

If just for graphing, plotting larger points might give you a good enough result.