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union polygons

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phtj
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I have a bunch of adjacent coplanar polygons that I want to union together to make one big polygon. Any ideas how to do this? See attached file for an example.

Attachments:
union_polygons.hipnc (44.9 KB)

Patrick
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tamte
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try Divide SOP with Remove Shared Edges checked
Tomas Slancik
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phtj
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thanks - that works great

Now I have a slightly more complicated union problem. I want to find that area of a bunch of co-planar polygons that are possibly overlapping, but the total area should only count overlapping areas once. See attached file for an example.

So I need to union them into a set of one or more larger polygons, and find the area of these (measure SOP followed by promote SOP)

So my question is now do I do the union.

Attachments:
union_polygons_2.hipnc (40.6 KB)

Patrick
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tamte
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you can union them with cookie SOP
but not all at once

to do it automatically you need to use foreach SOP
look at the example

Attachments:
union_polygons_2_fix.hipnc (53.5 KB)

Tomas Slancik
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Framestore, NY
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phtj
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Thanks tomas - that is a nice example

Just to get the hang of it, I re-did it in python, using 3d closed shapes instead of 2d closed shapes. See attached file.

Attachments:
union_boxes.hipnc (53.4 KB)

Patrick
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