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On 10/29/2010 11:26 PM, Ryan Michael wrote:
<blockquote
cite="mid:AANLkTikRz1CvNj9suOuyyS4w6DkA8yv0u_Vg4qF5fWgS@mail.gmail.com"
type="cite">I have a data set that I'm trying to interpolate, and in
some cases there are large swaths of area that are surrounded by
points, but don't contain any points. This produces a graph where
these interior regions have values determined by the nearest points.
<div><br>
</div>
<div>Rather than assuming that these points are accurately
represented by the surrounding points, I would prefer to not render
those grid points, and only show grid boxes which are actually
representative of data. Is there a way to do this? I was thinking I
could add second field and assign opacity to that, but I can't figure
out a way to get the field to be 'true' if there are points enclosed
and 'false' otherwise (or to simply count the number of enclosed
points.)</div>
<div><br>
</div>
<div>Any ideas?</div>
</blockquote>
<br>
Just a thought- You might create a buffer around all points at the max
distance you consider to be relevant for interpolation. The buffer will
thus cover only areas with a density of points of your choosing. The
"swaths" will be outside the buffer. Convert the buffer to a raster,
and make it a MASK. Now, after doing your point interpolation, use the
mask to set to null all the areas outside the buffer.<br>
<br>
<blockquote
cite="mid:AANLkTikRz1CvNj9suOuyyS4w6DkA8yv0u_Vg4qF5fWgS@mail.gmail.com"
type="cite">
<div><br>
</div>
<div>Thanks for any suggestions!</div>
<br>
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</blockquote>
<br>
<br>
<pre class="moz-signature" cols="72">--
Micha Silver
Arava Development Co. +972-52-3665918
<a class="moz-txt-link-freetext" href="http://www.surfaces.co.il">http://www.surfaces.co.il</a>
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