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I have a polygon layer which looks like this enter image description here.

I used the QGIS multiparts to singleparts tool and also polygon to lines. In both cases i got this type of result

enter image description here.

I want to extract polygon into individual lines like thisenter image description here

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this looks like a similar question, which may answer the question -… – Mark Sep 4 '13 at 8:11
I don't think the question is similar, and the answer is not useful as well. I use sextante in qgis. – neogeomat Sep 4 '13 at 8:15
not even if you convert the polys to lines first? – Mark Sep 4 '13 at 8:28
up vote 7 down vote accepted

You could use line-to-polygon tool (See How can I transform a polygon to a linestring in QGIS?) followed by v.clean command (See

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Is there something for qgis – neogeomat Sep 4 '13 at 8:59
The first tools is from QGIS and is available through sextante analysis tools; Second comand is from GRASS, but is also available through Sextante (You need to have grass installed and configured in sextante). – Alexandre Neto Sep 4 '13 at 11:28
take a look at :… – Kurt Sep 4 '13 at 15:17
first i used v.clean with break tool, then v.clean with rmdupl tool. The result are as i want but there are duplicates. – neogeomat Sep 4 '13 at 17:26

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