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</o:shapelayout></xml><![endif]--></head><body lang=DE link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-family:"Verdana",sans-serif'>I have a polygon dataset which needs to be dissolved by a certain item. That works fine. But when I calculate the area size for the new created Polygons in the next step using v.to.db, I find that the system summarizes all the polygons with the same value in the dissolve item, even if they are remote from each other (I mean, they do not touch). That might be correct if I want to handle them like a multipart feature, but those are not present in GRASS as far as I know. What I need is the area for each single polygon after removing the inside borders, no matter what value the polygon has. How to calculate that?<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Verdana",sans-serif'>I found that polygons with the same dissolve item also have the same cat number, which might be the reason for the common area size. But I don't know how to clear that without losing the connection to the database table containing the dissolve item.<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Verdana",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Verdana",sans-serif;mso-fareast-language:DE'>Best regards,<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Verdana",sans-serif;mso-fareast-language:DE'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Verdana",sans-serif;font-variant:small-caps;mso-fareast-language:DE'>Uwe</span><span style='font-family:"Verdana",sans-serif;mso-fareast-language:DE'><o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Verdana",sans-serif;mso-fareast-language:DE'><o:p> </o:p></span></p></div></body></html>