I am currently trying to perform the following steps in a MapBasic 5.0 program for MapInfo Professional 5.0: 1. open road coverage (polylines) 2. open county coverage (polygons) 3. open modeling grid coverage (polygons) 4. use Select statement to overlay county coverage onto road coverage, with the goal of breaking all roads at county boundaries: Select [field list], ObjectLen(road.obj,"mi") "calcroad", ObjectLen(Overlap(road.obj,county.obj),"mi") "seglength" from road, county where county.obj contains part road.obj into ctyroad 5. commit ctyroad, close ctyroad, open ctyroad to make ctyroad a base table 6. use Select statement to overlay modeling grid coverage onto ctyroad coverage Select [field list], ObjectLen(ctyroad.obj, modelgrd.obj),"mi") "gridctyrdmi" from ctyroad, modelgrd Where modelgrd.obj contains part ctyroad.obj into gridctyroad The lengths I am getting in (6) are the lengths of the original roads in the grid cell, not the length of the road segments in the grid cell. I need to resolve this matter because I need to overlay the county boundaries on the roads only once, but then I have multiple grids that I need to overlay onto the road segments. Later calculations depend on road segments by county and grid cell, not just roads by grid cell. What am I missing? How can I get step (4) to save objects that are the road segments, instead of the full roads for each road segment? TIA, Jo Ellen Brandmeyer ---------------------------------------------------------------------- To unsubscribe from this list, send e-mail to [EMAIL PROTECTED] and put "unsubscribe MAPINFO-L" in the message body, or contact [EMAIL PROTECTED]
