As far as I know the Area() calculates the area using the spherical method, which sees the world as a globe, and therefor projects the area onto a vertical plane before calculating the area.
If your data has been surveyed and so often actual has been measured and projected to this vertical plane, you should use the cartesian area calcualtion. But maybe you should check whether the coordinates in MapInfo are the same as they were in Microstation - of course they should be, but maybe this is the reason why the calculation is wrong ? Peter Horsb�ll M�ller GIS Developer Geographical Information & IT COWI A/S Odensevej 95 DK-5260 Odense S. Denmark Tel +45 6311 4900 Direct +45 6311 4908 Mob +45 5156 1045 Fax +45 6311 4949 E-mail [EMAIL PROTECTED] http://www.cowi.dk/gis Har du husket MapInfo Konferencen d. 8 og 9. september 2004. Tilmelding samt yderligere information kan ses p�: http://www.cowi.dk/GIS -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Thursday, September 09, 2004 4:21 PM To: Peter Horsb�ll M�ller Cc: [EMAIL PROTECTED] Subject: RE: MI-L Area between CAD and MapInfo Peter Above all thank you for your answer. We have our in format DGN we export it to DXF. In MapInfo, we import the DXF, indicating them the mentioned spherical projection, the calculated area is using the function Area in direct form, since the layer has spherical projection I suppose that the spherical method is used of I calculate of area, in the same way for the perimeter. According to the calculations the area that returns me this inside the range but bigger not smaller as you mention. I wanted to know about my friends of MapInfo which it is the it formulates of the I calculate of the area in Cartesian and spherical, and their comments in this respect. Sincerely Javier Quispe Mensaje citado por Peter Horsb�ll M�ller <[EMAIL PROTECTED]>: > This sounds strange to me. Which calculation method do you use ? > Spherical or Cartesian ? > > Normally the spherical area will be approx. 0.5 % smaller than the > cartesian area. > > Have you made sure that the length of the side in the region are > exactly 100 meter when imported into MapInfo ? How do you import it > into MapInfo ? > > Peter Horsb�ll M�ller > GIS Developer > Geographical Information & IT > > COWI A/S > Odensevej 95 > DK-5260 Odense S. > Denmark > > Tel +45 6311 4900 > Direct +45 6311 4908 > Mob +45 5156 1045 > Fax +45 6311 4949 > E-mail [EMAIL PROTECTED] > http://www.cowi.dk/gis > > Har du husket MapInfo Konferencen d. 8 og 9. september 2004. > Tilmelding samt yderligere information kan ses p�: > http://www.cowi.dk/GIS > > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > Sent: Wednesday, September 08, 2004 12:26 AM > To: [EMAIL PROTECTED] > Subject: MI-L Area between CAD and MapInfo > > > Friends > > I have a great inconvenience regarding the way in that MapInfo > calculates the area of objects regions. In an ambient CAD we have a > squared object or rectangle of 10000 m2 or 1 hectare, when it is > imported in MapInfo with the wanted spherical projection (UTM PSAD 56 > Zone 18 South) the resulting area is bigger in 39 m2, being this too > big difference. Is my consultation as MapInfo it calculates the area? > which is the it formulates used in this I calculate?, this because > when it is changed to Cartesian system, the area between CAd and MapInfo is the same > > I expect your help > > Javier Quispe > > > .:------------------------------------------------------------:. > Proyecto Especial Titulaci�n de Tierras y Catastro Rural - PETT > Ministerio de Agricultura Lima -Per� > .:------------------------------------------------------------:. > > --------------------------------------------------------------------- > List hosting provided by Directions Magazine | www.directionsmag.com | > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: > [EMAIL PROTECTED] > Message number: 13241 > > > .:------------------------------------------------------------:. Proyecto Especial Titulaci�n de Tierras y Catastro Rural - PETT Ministerio de Agricultura Lima -Per� .:------------------------------------------------------------:. --------------------------------------------------------------------- List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 13269
