Hi John! Assuming that your buildnings all are region objects, it may come as a pleasant surprise to learn that the area (and perimeter) are inherent attributes to such objects. On the other hand, if they are line objects they have by definition no area, even if they are closed. In that case, however, MapInfo can convert them to region objects. Back to assupmtion one: double click any building and you will se the area, expressed in the current unit.
If you need to explicitly list the area values in the table you need to first create a new column and then populate that with the area value. It would appear something like this in the MabBasic Window. Alter Table "Buildings" ( add Build_Area Float ) Interactive Update Buildings Set Build_Area = Area(obj, "sq m") But you need to know that the values thus exposed will lose the connection with the spatial object. They will not be updated if building footprints are changed or new buildings added. Yet another way is to create a temporary column, and populate it using the same expression. The drawback of this method is that the temp column is lost to other users unless you use the table from a workspace. On the other hand, the area values will be dynamic. H�lsning/ Best regards Mats.E ________________________ FB Engineering AB S�dra F�rstadsgatan 26 211 43 Malm� OBS nya telefonnummer! Tel: 040-660 2550 Mobil: 0705-27 60 27 Fax: 040-660 2599 e-post: [EMAIL PROTECTED] http://www.fbe.se "John Nott" <[EMAIL PROTECTED]> 2004-09-28 14:33 Till <[EMAIL PROTECTED]> Kopia �rende MI-L MaoInfo Area Calculator Hello!! Does anyone know a way to calculate the areas of a layer of building outlines and store them as an attribute automatically? I cann't go through them individually as there is over 2,000!!! Thanks, - john John Nott Consultant/GIS Analyst ROGER TYM & PARTNERS Fairfax House, 15 Fulwood Place, London, WC1V 6HU t 020 7831 2711 f 020 7831 7653 e [EMAIL PROTECTED] w www.tymconsult.com The information in this email is confidential. It may also be legally privileged. It is intended only for the stated addressee(s) and access to it by any other person is unauthorised. If you are not an addressee, you must not disclose, copy, circulate or in any other way use or rely upon the information contained in this email. Such unauthorised use may be unlawful. If you have received this email in error, please reply immediately to this effect and delete it (and all copies) from your system (with thanks). This message and any attached files have been scanned for the presence of computer viruses. However, you are advised that you open any attachment at your own risk. --------------------------------------------------------------------- List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 13527
