<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Hi<div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On 08 Jul 2016, at 11:30 AM, Zoltan Szecsei <<a href="mailto:zoltans@geograph.co.za" class="">zoltans@geograph.co.za</a>> wrote:</div><br class="Apple-interchange-newline"><div class="">
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Hi again,<br class="">
OK - it's not an index thing. More than one 'a' polygon has received
the 'b' attribute from the wrong 'b' polygon even though the
coordinate is inside the correct 'b' polygon.<br class="">
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So the next step is to suspect the index.intersects result.<br class=""></div></div></blockquote><div><br class=""></div><div>Could you share a small testable dataset that replicates it? I made a noddy test dataset here when playing with it last night which worked fine, but it only had 2 polygons in it...</div><br class=""><blockquote type="cite" class=""><div class=""><div bgcolor="#FFFFFF" text="#000000" class="">
Note the coords are in LatLong "small numeric values. I can see we
are using a null-length box (ie: a point) to select from 'b'.<br class="">
What is the internal precision of the QgsPoint?<br class=""></div></div></blockquote><div><br class=""></div><div>the x and y properties of QgsPoint are both doubles...it depends on your platform what that means but typically</div><div><br class=""></div><div><a href="http://qgis.org/api/2.6/classQgsPoint.html" class="">http://qgis.org/api/2.6/classQgsPoint.html</a></div><div><br class=""></div><div>According to wikipedia on a 64 bit machine it should be:</div><div><br class=""></div><div><ul style="margin: 0.3em 0px 0px 1.6em; padding: 0px; list-style-image: url(data:image/svg+xml,%3C%3Fxml%20version%3D%221.0%22%20encoding%3D%22UTF-8%22%3F%3E%0A%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20version%3D%221.1%22%20width%3D%225%22%20height%3D%2213%22%3E%0A%3Ccircle%20cx%3D%222.5%22%20cy%3D%229.5%22%20r%3D%222.5%22%20fill%3D%22%2300528c%22%2F%3E%0A%3C%2Fsvg%3E%0A); color: rgb(37, 37, 37); font-family: sans-serif; font-size: 14px;" class=""><li style="margin-bottom: 0.1em;" class=""><a href="https://en.wikipedia.org/wiki/Sign_bit" title="Sign bit" style="text-decoration: none; color: rgb(11, 0, 128); background-image: none; background-position: initial initial; background-repeat: initial initial;" class="">Sign bit</a>: 1 bit</li><li style="margin-bottom: 0.1em;" class=""><a href="https://en.wikipedia.org/wiki/Exponent" class="mw-redirect" title="Exponent" style="text-decoration: none; color: rgb(11, 0, 128); background-image: none; background-position: initial initial; background-repeat: initial initial;">Exponent</a> width: 11 bits</li><li style="margin-bottom: 0.1em;" class=""><a href="https://en.wikipedia.org/wiki/Significand" title="Significand" style="text-decoration: none; color: rgb(11, 0, 128); background-image: none; background-position: initial initial; background-repeat: initial initial;" class="">Significand</a> <a href="https://en.wikipedia.org/wiki/Precision_(arithmetic)" class="mw-redirect" title="Precision (arithmetic)" style="text-decoration: none; color: rgb(11, 0, 128); background-image: none; background-position: initial initial; background-repeat: initial initial;">precision</a>: 53 bits (52 explicitly stored)</li></ul><div class=""><br class=""></div><div class=""><br class=""></div></div><br class=""><blockquote type="cite" class=""><div class=""><div bgcolor="#FFFFFF" text="#000000" class="">
My coord attributes are 'double Real 19,10' <br class="">
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In a script, when you select with a point, what is the snapping
tolerance?<br class="">
</div></div></blockquote><div><br class=""></div><div>To use snapping you would need to use the QGIS snapping api - otherwise absolute geometry operations are being done.</div><br class=""><blockquote type="cite" class=""><div class=""><div bgcolor="#FFFFFF" text="#000000" class="">My project CRS is epsg 4326 - so it should be OK.<br class=""></div></div></blockquote><div><br class=""></div><div>Yup. If you wanted to be fancy, you could extract a layer of the tie points (FptnLat. FptnLong) so that you can actually visualise the points in relation to the polygons. Maybe you have some that don't actually intersect a poly...</div><br class=""><blockquote type="cite" class=""><div class=""><div bgcolor="#FFFFFF" text="#000000" class="">
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FWIW, b.name is string 60 which is copied into a.name string 32 -
but the contents are shorter that 32 chars.<br class=""></div></div></blockquote><div><br class=""></div><div>I think QGIS will just truncate it if the name is longer than 32 chars.</div><div><br class=""></div><div>T</div><br class=""><blockquote type="cite" class=""><div bgcolor="#FFFFFF" text="#000000" class="">
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Any thoughts anyone?<br class="">
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Regards,<br class="">
Zoltan<br class=""><br class=""></div></blockquote></div><br class=""></div></body></html>