Terry, I don't know if you've had a reply to this but in case not, I'll throw in my 2p worth.
I'm not clear whether you're after a utility that will select the corresponding zone when you select an ESU, or whether you simply want to update the ESU table with the ID of the corresponding zone. Presumably it's the later, because otherwise you should be able to see on screen which zone an ESU is in. To update the ESU table, use the 'Update Column' command (from the 'Table' menu). Table to update being the ESU table, Get Value from Table is the Zone table. The Column to Update will then default to a temporary column - choose the correct one if you have set one up for the purpose. Click on the Join button and set it up so that the Object from table Zone contains object from table ESU (meaning the centroid of the ESU is inside the zone boundary). Click OK. Set 'Calculate' to 'Value' (the default) and then in the 'of:'list, select the column from the Zone table that you want to update the ESU table, presumably an ID column. Click 'OK' and that should do it. You might get some anomalies depending on your data - e.g. if the shape of an ESU is mostly inside one boundary, but because of the shape of it and / or the zones, the centroid is actually within another zone. This type of thing should be rare but some checking on the results is advisable. Please note that temporary columns are not saved, so you'll either have to 'Save a Copy As' of the ESU table or Alter the table structure to include a new column for the purpose and then save after using Update Table.. I don't think the different projections will cause a problem, but I could be wrong. Hope this helps, Keith -----Original Message----- From: Terry McDonnell [mailto:[EMAIL PROTECTED] Sent: 23 February 2004 12:10 To: [EMAIL PROTECTED] Subject: MI-L Getting corresponding info from superimposed map layer Hello, All. I'm fairly new to MapInfo and MapBasic but I'm picking it up pretty well. I have this nice problem that you may be able to solve or point out to me that it's an easy, common requirement. I have 2 map layers: Streets, and Zones. "Streets" comprises lots of Elementary Street Units (ESUs) - polylines representing contiguous sections of road. "Zones" comprises lots of irregular polygons, representing geographical areas, and the roads run through these. My problem is that, as I select ESUs on one layer, I need to identify, in the other layer, what zone(s) the roads go through (these are to be stored in a Foxpro database). BUT, the 2 maps have no data or key linking them. To my inexperienced mind (possibly I'm wrong), the problem is further exacerbated by the fact that the 2 maps have different projections ("Streets" is British National Grid and "Zones" is Long/Lat). Can anyone please help TIA Terry This email and any attached files are confidential and copyright protected. If you are not the addressee, any dissemination of this communication is strictly prohibited. Unless otherwise expressly agreed in writing, nothing stated in this communication shall be legally binding. --------------------------------------------------------------------- List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 10584
