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@@ -82,8 +82,6 @@ for use with arbitrarily large input files<!-- without a small value for percent
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The default map <b>type</b>=<tt>FCELL</tt> is intended as compromise between
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preserving data precision and limiting system resource consumption.
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-If reading data from a <tt>stdin</tt> stream, the program can only run using
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-a single pass.
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<h3>Setting region bounds and resolution</h3>
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@@ -176,33 +174,32 @@ Typical commands to create a DEM using bsplines:
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<h2>EXAMPLE</h2>
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-Import the <a href="http://www.grassbook.org/data_menu2nd.phtml">Jockey's
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-Ridge, NC, LIDAR dataset</a>, and process into a clean DEM:
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+This example is analogous to the example used in the GRASS wiki page for
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+<a href="http://grass.osgeo.org/wiki/LIDAR#Import_LAS_as_raster_DEM">importing LAS as raster DEM</a>.
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+<p>
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+The sample LAS data are in the file "Serpent Mound Model LAS Data.las",
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+available at
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+<a href="http://www.appliedimagery.com/downloads/sampledata/Serpent%20Mound%20Model%20LAS%20Data.las">appliedimagery.com</a>
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<div class="code"><pre>
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- # scan and set region bounds
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- r.in.xyz -s fs=, in=lidaratm2.txt out=test
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- g.region n=35.969493 s=35.949693 e=-75.620999 w=-75.639999
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- g.region res=0:00:00.075 -a
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- # create "n" map containing count of points per cell for checking density
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- r.in.xyz in=lidaratm2.txt out=lidar_n fs=, method=n zrange=-2,50
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- # check point density [rho = n_sum / (rows*cols)]
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- r.univar lidar_n | grep sum
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- # create "min" map (elevation filtered for premature hits)
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- r.in.xyz in=lidaratm2.txt out=lidar_min fs=, method=min zrange=-2,50
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- # zoom to area of interest
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- g.region n=35:57:56.25N s=35:57:13.575N w=75:38:23.7W e=75:37:15.675W
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- # check number of non-null cells (try and keep under a few million)
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- r.univar lidar_min | grep '^n:'
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- # convert to points
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- r.to.vect -z feature=point in=lidar_min out=lidar_min_pt
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- # interpolate using a regularized spline fit
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- v.surf.rst layer=0 in=lidar_min_pt elev=lidar_min.rst
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- # set color scale to something interesting
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- r.colors lidar_min.rst rule=bcyr -n -e
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- # prepare a 1:1:1 scaled version for NVIZ visualization (for lat/lon input)
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- r.mapcalc "lidar_min.rst_scaled = lidar_min.rst / (1852*60)"
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- r.colors lidar_min.rst_scaled rule=bcyr -n -e
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+ # using v.in.lidar to print file info and to create a new location
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+
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+ # print LAS file info
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+ v.in.lidar -p input="Serpent Mound Model LAS Data.las"
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+
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+ # create location with projection information of the LAS data
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+ v.in.lidar -i input="Serpent Mound Model LAS Data.las" location=Serpent_Mound
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+
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+ # quit and restart GRASS in the newly created location "Serpent_Mound"
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+
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+ # scan the extents of the LAS data
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+ r.in.lidar -sg input="Serpent Mound Model LAS Data.las"
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+
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+ # set the region to the extents of the LAS data, align to resolution
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+ g.region n=4323641.57 s=4320942.61 w=289020.90 e=290106.02 res=1 -ap
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+
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+ # import as raster DEM
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+ r.in.lidar input="Serpent Mound Model LAS Data.las" output=Serpent_Mound_Model_LAS_Data method=mean
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</pre></div>
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<br>
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@@ -250,6 +247,7 @@ Development Team.
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<a href="r.to.rast3.html">r.to.rast3</a><br>
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<a href="r.to.vect.html">r.to.vect</a><br>
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<a href="r.univar.html">r.univar</a><br>
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+<a href="v.in.lidar.html">v.in.lidar</a><br>
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<a href="v.in.ascii.html">v.in.ascii</a><br>
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<a href="v.surf.rst.html">v.surf.rst</a><br>
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<br>
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