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<p class=MsoNormal>Are there any gdal/geos based utility out there that do a
topological union between two sets of geometry (shape files)?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>A topological union results in existing geometry being split
into multiple pieces and each new resulting polygon having all of the
attributes of both source polygongs. For example in a Venn diagram, 2
overlapping circles would result in 3 polygons.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>A non-topological union results in all geometry being in the
same set, but w/o any new areas being created where there is overlap. For
example, in a Venn diagram, even though two circles are overlapping, the
overlapped portion would not result in a new polygon; there would only be the
two original circles as polygons.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks for the help,<o:p></o:p></p>
<p class=MsoNormal>Craig<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
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