Bob: >I'm trying to overlay the 1990 block groups onto the 2000 block >groups. These are the geography/data cds that I bought from Caliper. > >What happens is the overlay starts to process. and then it stops with >the message "Encountered topological problems when processing >polygons 14708142 and 18188130. Error at or near coordianate (- >119571922,364891287) Click OK to continue. Reference info: >aggr,321,0."
This stems from errors in the original TIGER/Line files: they were not topologically correct there! >My goal is to calculate some changes in demographics. Like the growth >in hispanic population from 1990 to 2000. Please check out the Time Series Data at (http://www.caliper.com/DataCDs/PopulationEstimates.htm). We have done the heavy lifting for you. Peter ---------------------------------------------------------------- Peter H. Van Demark Director of GIS Products and Training Phone: 617-527-4700 Caliper Corporation Fax: 617-527-5113 1172 Beacon Street E-mail: [EMAIL PROTECTED] Newton MA 02461-9926 Web site: http://www.caliper.com Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Maptitude/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
