I fear it isn't possible to do it in one single step. If I had to do it in a rush I would:<div><br></div><div> - add a column to the grid layer and populate it with the square area. Your squares are fixed, so you can populate it manually, otherwise the field calculator could be used to do it</div>
<div> - do an intersect between you polygon and the grid (Vector -> Geoprocessing)</div><div> - add another column to the intersection result, and populate it again with the area, using the Filed Calculator.</div><div>
- AT this point you will have the original area and the new area. With Field Calculator populate a third column with the new area / original area ratio (x 100 if you want the precentage).</div><div> - Select the squares where the percentega is over 90.</div>
<div><br></div><div>How to obtain the unclipped, original, squares? You can do a spatial join between the original grid, and the selected squares (above 90) from the intersection result.</div><div><br></div><div>Giovanni<br>
<br><div class="gmail_quote">2013/4/11 Levy Vincent <span dir="ltr"><<a href="mailto:v.levy@cbnbl.org" target="_blank">v.levy@cbnbl.org</a>></span><br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<p class="MsoNormal">Hello,<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal"><span lang="EN-US">I have a layer with a big polygon and another layer which is a grid (made of squares 10X10m). The grid is larger than the big polygon and cover it entirely.
<u></u><u></u></span></p>
<p class="MsoNormal"><span lang="EN-US">I want to keep only the squares of the grid contained in the polygon. I know how to intersect my two layers to select all the squares of the grid inside my “big polygon”.<u></u><u></u></span></p>
<p class="MsoNormal"><span lang="EN-US">The problem is on the border : I would like to select only the squares which 90% of their surface is contained in the big polygon.<u></u><u></u></span></p>
<p class="MsoNormal"><span lang="EN-US">Is there any plug-in or another solution to do it easily?<u></u><u></u></span></p>
<p class="MsoNormal"><span lang="EN-US">I hope somebody could help me, thank you for your answer,<u></u><u></u></span></p>
<p class="MsoNormal"><span lang="EN-US"><u></u> <u></u></span></p>
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<br></blockquote></div><br><br clear="all"><div><br></div>-- <br>Giovanni Allegri<br><a href="http://about.me/giovanniallegri" target="_blank">http://about.me/giovanniallegri</a><br>blog: <a href="http://blog.spaziogis.it" target="_blank">http://blog.spaziogis.it</a><br>
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