I am not getting any responses. :-) Am I doing something really dumb? Is this the right forum for this kind of question?<div><br></div><div>Thanks,</div><div><br></div><div>Aren<br><br><div class="gmail_quote">On Sun, Feb 13, 2011 at 8:02 AM, Aren Cambre <span dir="ltr"><<a href="mailto:aren@arencambre.com">aren@arencambre.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Maybe I could clarify. Here's the command:<div><b><font face="'courier new', monospace" color="#3366FF">v.kernel --verbose input=master_grass7 output=master_grass7a_heatmap stddeviation=.0001</font></b></div>
<div><br></div><div>Here's the command output:</div><div><div><b><font face="'courier new', monospace" color="#3366FF">STDDEV: 0.000100</font></b></div><div><b><font face="'courier new', monospace" color="#3366FF">RES: 200.000000<span style="white-space:pre-wrap"> </span>ROWS: 1000<span style="white-space:pre-wrap"> </span>COLS: 1000</font></b></div>
<div><b><font face="'courier new', monospace" color="#3366FF"><br></font></b></div><div><b><font face="'courier new', monospace" color="#3366FF">Writing output raster map using smooth parameter=0.000100.</font></b></div>
<div><b><font face="'courier new', monospace" color="#3366FF"><br></font></b></div><div><b><font face="'courier new', monospace" color="#3366FF">Normalising factor=0.000000.</font></b></div>
<div><b><font face="'courier new', monospace" color="#3366FF">Maximum value in output: 0.000000e+000.</font></b></div></div><div><br></div><div>If I change stddeviation to <b><font face="'courier new', monospace">100</font></b>, here's what I get:</div>
<div><div><b><font face="'courier new', monospace" color="#3366FF">STDDEV: 100.000000</font></b></div><div><b><font face="'courier new', monospace" color="#3366FF">RES: 200.000000<span style="white-space:pre-wrap"> </span>ROWS: 1000<span style="white-space:pre-wrap"> </span>COLS: 1000</font></b></div>
<div><b><font face="'courier new', monospace" color="#3366FF"><br></font></b></div><div><b><font face="'courier new', monospace" color="#3366FF">Writing output raster map using smooth parameter=100.000000.</font></b></div>
<div><b><font face="'courier new', monospace" color="#3366FF"><br></font></b></div><div><b><font face="'courier new', monospace" color="#3366FF">Normalising factor=64826.350188.</font></b></div>
<div><b><font face="'courier new', monospace" color="#3366FF">Maximum value in output: 0.000000e+000.</font></b></div></div><div><br></div><div>Either way, the resulting raster is a large salmon/pink square. I have no idea what I'm doing wrong. I've tried varying the <b>stddeviation </b>parameter from 100 to .0001 and some values in between, and I don't get anything different. Heck, I just now used 1000000 and .000001 and got nothing different.</div>
<div><br></div><div>I was really hoping to make a high res heat map of these 2.5 million points and overlay on to a street map layer.</div><div><br><font color="#888888">Aren</font><div><div></div><div class="h5"><br><br>
<div class="gmail_quote">On Fri, Feb 11, 2011 at 9:45 PM, Aren Cambre <span dir="ltr"><<a href="mailto:aren@arencambre.com" target="_blank">aren@arencambre.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">I am not clear how to get useful results out of v.kernel. I have a vector layer imported from PostGIS that has about 2.5 million points. I want to make a high density raster to show where these points are clustered. I can get the vector layer to display in GRASS just fine, albeit without attributes because of <a href="http://trac.osgeo.org/grass/ticket/1274" target="_blank">http://trac.osgeo.org/grass/ticket/1274</a>.<div>
<br></div><div><div>It's not clear to me, based on <a href="http://grass.fbk.eu/gdp/html_grass64/v.kernel.html" target="_blank">http://grass.fbk.eu/gdp/html_grass64/v.kernel.html</a>, how you can get it to do something besides make a big, pinkish (salmon-red?) square?</div>
<div><br></div><font color="#888888"><div>Aren</div></font></div>
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