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I would like to modify two polygon at the one time because these two data has same point and line. Is it possible??

In the present circumstance, I have to modify polygon one by one. First, I modify one polygon. After that,another polygon will be modified with snap function for overlapping to another polygon.

Thank you so much in advance.

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Are you using a shapefile that has line topology instead of polygon topology? You should just need to grab the vertex and drag that to a new position and change the shape of all the polygons. – JLP Wisc. Jan 23 '13 at 19:56
I might missed it, but could you name the GIS softwate that you are using?! – dof1985 Jan 23 '13 at 19:57
I am using QGIS 1.8.0. – Jermain Marthin Jan 24 '13 at 8:56

If you are using ArcGIS, use map topology for editing shared geometry of shapefiles.

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We're looking for long answers that provide some explanation and context. Don't just give a one-line answer; explain why your answer is right, ideally with citations. Answers that don't include explanations may be removed.

In QGIS go to Settings->Snapping Options and click on 'Enable Topological Editing' at the bottom of the dialog box.

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QGIS 2.0 bugs out on me (known bug Win 7 x64) So I dropped to 1.8 - Do you know if there is there a topology validation/checking tool? – Barrett Jan 13 '14 at 17:28
I believe this tool existed in V1.8 as well. However, if the 64 bit version of QGIS is giving you problem, you could use the 32 bit version. I use this on Windows 7 64 operating system on a daily basis with no problems. – MappaGnosis Jan 13 '14 at 19:46
wow thanks. didn't try 32 bit – Barrett Jan 13 '14 at 19:48

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