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Hi, <br><div style="text-align: left; "><font class="Apple-style-span" face="Arial"><b><br></b></font></div><font class="Apple-style-span" face="Tahoma">I'm working with a database for the three-dimensional interpolation in</font><br><font class="Apple-style-span" face="Tahoma"> GRASS which is composed of data ranging from 0 to 100, and</font><br><font class="Apple-style-span" face="Tahoma"> coordinates x,y,z, to conduct a zoning 3D attribute.</font><br><font class="Apple-style-span" face="Tahoma"> I'm using v.vol.rst, but I'm having trouble finding the best</font><br><font class="Apple-style-span" face="Tahoma"> parameters for 3D interpolation.</font><br><font class="Apple-style-span" face="Tahoma"> I realized several simulations varying the parameters npmin,segmax, tension and smooth.</font><br><font class="Apple-style-span" face="Tahoma"> However, using as example the default parameters of v.vol.rst (tension =</font><br><font class="Apple-style-span" face="Tahoma"> 40, smooth = 0.1, = 50 segmax, npmin = 200 and dmin= 0.5) the results generate voxels with an</font><br><font class="Apple-style-span" face="Tahoma"> average of 77 and standard deviation equal 8.</font><br><font class="Apple-style-span" face="Tahoma"> But most of my input data is close to a range of values from 90 to</font><br><font class="Apple-style-span" face="Tahoma"> 100 (46% of vector points), but the volume voxels generated for</font><br><font class="Apple-style-span" face="Tahoma"> this interval has a ratio of 3%.</font><br><font class="Apple-style-span" face="Tahoma"> How these parameters influence the equation of the spline v.vol.rst?</font><br><font class="Apple-style-span" face="Tahoma"> What parameters could be influence this result?</font><br><font class="Apple-style-span" face="Tahoma"> Whereby the highest percentage of interpolated values is</font><br><font class="Apple-style-span" face="Tahoma"> between the range of values from 75 to 90 and not 90 to 100.</font><br><font class="Apple-style-span" face="Tahoma"> Why are the values from 90 to 100 may be having a small weight in</font><br><font class="Apple-style-span" face="Tahoma"> the interpolation?</font><br><font class="Apple-style-span" face="Tahoma"><br> Thanks</font><br><font class="Apple-style-span" face="Tahoma"> </font><div><font class="Apple-style-span" face="Tahoma">Vivian</font><br><font class="Apple-style-span" face="Tahoma"><br></font></div> </body>
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