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@@ -16,11 +16,11 @@ it is impossible to determine interchangeable path from any cell.
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<p>
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The upstream method offers two alternative modes switched with <em>-n</em>
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-flag: the <em>nearest local maximum/divide</em>: is the shortest path to
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-the local maximum (default option); and the <em>farthest maximum/divide</em>:
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-is the longest path.
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-In hydrological sense, the <em>nearest</em> option means the shortest path which a
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-particle of water must run from the divide to reach a particular pixel,
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+flag: the <em>nearest local maximum/divide</em> is the shortest path to
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+the local maximum; and the <em>farthest maximum/divide</em>
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+is the longest path (default option).
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+In hydrological sense, the <em>nearest</em> option means the shortest path
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+which a particle of water must run from the divide to reach a particular pixel,
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while the <em>farthest</em> option means the possible longest path.
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<p>
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@@ -34,7 +34,8 @@ it calculates the distance only for the outlet (downstream).
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If the <em>subbasin</em> option is set on, it calculates the distance to
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outlet for every subbasin separately. The <em>subbasin</em> option acts
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similarly to a subbasin mask. The module <em>r.stream.basins</em> can be
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-used to prepare the stream network map taken in input by <em>r.stream.distance</em>.
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+used to prepare the stream network map taken in input by
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+<em>r.stream.distance</em>.
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In fact it can be used to individuate basins and subbasins.
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<p>
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@@ -79,16 +80,16 @@ shall be of integer type (CELL). </dd>
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DCELL. </dd>
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<dt><b>method</b></dt>
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-<dd>It is possible to calculate the distance with two method: <b>downstream</b> from
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-any raster cell to the nearest stream cell / junction cell or outlet or
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+<dd>It is possible to calculate the distance with two method: <b>downstream</b>
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+from any raster cell to the nearest stream cell / junction cell or outlet or
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<b>upstream</b> from any cell upstream to the nearest maximum or divide.</dd>
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<dt><b>difference</b></dt>
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-<dd>Name of output map of elevation difference to the targer (outlet, node,
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+<dd>Name of output map of elevation difference to the target (outlet, node,
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stream, divide, maximum) along watercoures. The map is of FCELL type.</dd>
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<dt><b>distance</b></dt>
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-<dd>Name of output map of distance to the targer (outlet, node, stream,
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+<dd>Name of output map of distance to the target (outlet, node, stream,
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divide, maximum) along watercoures. The map is of FCELL type.</dd>
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</dl>
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@@ -115,23 +116,25 @@ r.mapcalc expression = "dist_corrected = sqrt(distance^2 + elevation^2)"
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</pre></div>
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<p>
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-The module can work only if direction map, streams map and region have the same settings.
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+The module can work only if direction map, streams map and region have the same
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+settings.
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This is checked by default. If resolutions differ, the module informs about
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it and stops. Region boundary and maps boundary may differ but it may lead
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to unexpected results. The elevation map is not affected by this restriction
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and can have whatever resolution.
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<p>
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-It is also required that <em>stream_rast</em> and <em>direction</em> maps come
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-from the same source, e.g. both from <em>r.stream.extract</em>. If the stream network
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-was generated with MFD method also MFD direction map must be used.
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+It is also required that <em>stream_rast</em> and <em>direction</em> maps come
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+from the same source, e.g. both from <em>r.stream.extract</em>. If the stream
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+network was generated with MFD method also MFD direction map must be used.
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<p>
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-Probably one of the most important features of <em>r.stream.distance</em> is the ability to
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-calculate the distance not only for streams generated by <em>r.stream.extract</em>, but also
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-for any integer map, as long ast the resolution corresponds to that of <em>direction</em> map.
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-It can be a lake, swamp, depression and lake boundaries even divided into smaller fragments each
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-with its own category.
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+Probably one of the most important features of <em>r.stream.distance</em> is
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+the ability to calculate the distance not only for streams generated by
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+<em>r.stream.extract</em>, but also for any integer map, as long ast the
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+resolution corresponds to that of <em>direction</em> map.
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+It can be a lake, swamp, depression and lake boundaries even divided into
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+smaller fragments each with its own category.
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<h2>EXAMPLE</h2>
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@@ -165,9 +168,6 @@ r.stream.distance -o stream_rast=outlet direction=direction elevation=elevation
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<h2>SEE ALSO</h2>
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<em>
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-<a href="r.stream.extract.html">r.stream.extract</a>,
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-<a href="r.stream.order.html">r.stream.order</a>,
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-<a href="r.stream.basins.html">r.stream.basins</a>,
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<a href="r.mapcalc.html">r.mapcalc</a>,
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<a href="r.reclass.html">r.reclass</a>,
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<a href="r.stream.channel.html">r.stream.channel</a>,
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@@ -186,6 +186,7 @@ also <a href="http://grasswiki.osgeo.org/wiki/R.stream.*_modules">r.streams.*
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modules</a> wiki page.
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<h2>AUTHOR</h2>
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+
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Jarek Jasiewicz, Adam Mickiewicz University, Geoecology and Geoinformation
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Institute.
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