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@@ -44,12 +44,14 @@ of 45 degrees.
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<P>
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<P>
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GRASS aspect maps are measured using Cartesian conventions, i.e. in degrees
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GRASS aspect maps are measured using Cartesian conventions, i.e. in degrees
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counterclockwise from east. e.g.:
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counterclockwise from east. e.g.:
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-<pre>
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+
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+<div class="code"><pre>
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90 North
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90 North
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180 West
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180 West
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270 South
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270 South
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-0,360 East</pre>
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-<P>
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+0,360 East
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+</pre></div>
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+
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They can be created from a raster elevation map with <em>r.slope.aspect</em>.
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They can be created from a raster elevation map with <em>r.slope.aspect</em>.
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<P>
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<P>
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Compass type aspect maps are measured in degrees clockwise from north.
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Compass type aspect maps are measured in degrees clockwise from north.
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@@ -62,12 +64,12 @@ direction "to", as opposed to atmospheric conventions (direction "from").
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Convert U,V velocity component maps into magnitide,direction maps for use
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Convert U,V velocity component maps into magnitide,direction maps for use
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with <em>d.rast.arrow</em>:
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with <em>d.rast.arrow</em>:
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-<pre>
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- r.mapcalc 'magnitude = sqrt(U_map^2 + V_map^2)'
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- r.mapcalc 'direction = atan(U_map, V_map)'
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- d.rast.arrow map=direction type=grass magnitude_map=magnitude skip=3 grid=none
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-</pre>
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-<BR>
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+
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+<div class="code"><pre>
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+r.mapcalc "magnitude = sqrt(U_map^2 + V_map^2)"
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+r.mapcalc "direction = atan(U_map, V_map)"
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+d.rast.arrow map=direction type=grass magnitude_map=magnitude skip=3 grid=none
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+</pre></div>
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<H2>SEE ALSO</H2>
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<H2>SEE ALSO</H2>
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