I used -n flag. The surface is now more realistics and appears allineated to the narrower IDWs results: <a href="http://www.geospatial.it/allegri/IDW4.png" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">http://www.geospatial.it/allegri/IDW5.png</a> .<br>
I can't access your PhD thesis...<br><br>Giovanni<br><br><div><span class="gmail_quote">2008/2/13, Luigi Ponti <<a href="mailto:lponti@infinito.it">lponti@infinito.it</a>>:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Dear Paul,<br><br>I have found your PhD thesis excerpt very interesting: thanks for<br>sharing it.<br>> Date: Tue, 12 Feb 2008 21:31:44 +0000 (GMT)<br>> From: Paul Kelly <<a href="mailto:paul-grass@stjohnspoint.co.uk">paul-grass@stjohnspoint.co.uk</a>><br>
> Subject: Re: [GRASS-user] strange behaviour of v.surf.idw<br>> To: "G. Allegri" <<a href="mailto:giohappy@gmail.com">giohappy@gmail.com</a>><br>> Cc: grassuser <<a href="mailto:grass-user@lists.osgeo.org">grass-user@lists.osgeo.org</a>><br>
><br>> Also, have you tried running using the -n flag (no indexing) and comparing<br>> the results. I think they should be the same for all regions then but<br>> might turn up something else interesting.<br>><br>
I started using v.surf.idw (for irregularly spaced points) in grass6.0<br>with no -n flag, then in 6.1 I noticed that the output raster changed<br>from what it used to be (i.e., some stair-like artifacts appeared) and<br>
it was restored to the original look (i.e., a much smoother look) by<br>adding the -n flag. By looking at your PhD thesis excerpt, it looks like<br>the -n flag should only make the interpolation faster: I wonder if you<br>
have any idea why there may be differences, as you also say above.<br><br>Kind regards,<br><br>Luigi<br><br>_______________________________________________<br>grass-user mailing list<br><a href="mailto:grass-user@lists.osgeo.org">grass-user@lists.osgeo.org</a><br>
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