<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Hi <div><br></div><div>should be something like (untested)</div><div><br></div><div><span class="Apple-style-span" style="font-family: Times; "><tt>r.mapcalc 'elevation300map=if((originalelevationmap > 300),originalelevationmap,NULL())'</tt></span></div><div><span class="Apple-style-span" style="font-family: Times; "><br></span></div><div><span class="Apple-style-span" style="font-family: Times; "><tt></tt></span><span class="Apple-style-span" style="font-family: Times; ">this means:</span></div><div><span class="Apple-style-span" style="font-family: Times; "><br></span></div><div><span class="Apple-style-span" style="font-family: Times; ">if originalelevationmap > 300 get the value from the originalelevationmap, otherwise the value should be NULL and all is wirtten to the map elevation300map.</span></div><div><span class="Apple-style-span" style="font-family: Times; "><br></span></div><div><span class="Apple-style-span" style="font-family: Times; ">Otherwise take a closer look to</span></div><div><font class="Apple-style-span" face="Times"><a href="http://grass.osgeo.org/gdp/html_grass64/r.mapcalc.html">http://grass.osgeo.org/gdp/html_grass64/r.mapcalc.html</a></font></div><div><span class="Apple-style-span" style="font-family: Times; "><br></span></div><div><span class="Apple-style-span" style="font-family: Times; ">I haven't used r.mapcalc for a long time so I don't know if there had been changes in the syntax - the trick is to use the if clause implemented in r.mapcalc. I have no QGIS/GRASS installed on this pc...</span></div><div><span class="Apple-style-span" style="font-family: Times; "><br></span></div><div><span class="Apple-style-span" style="font-family: Times; ">I hope that helps and merry christmas</span></div><div><span class="Apple-style-span" style="font-family: Times; ">Malte</span></div><div><span class="Apple-style-span" style="font-family: Times; "> </span><br><div><div>Am 26.12.2010 um 11:51 schrieb Catlike:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div><br>Thank you for reading.<br>I am trying to use r.mapcalc, through QGIS, to take an elevations raster<br>with a wide variety of values and create a new elevations raster which only<br>contains those cells that have a value over a certain number (in this case,<br>300 meters). <br>Unfortunately, the QGIS graphic user interface does not show me what the<br>actual command I create is. <br>What I get when I run the command is a new raster in which every cell has<br>been converted to equal 300 meters! <br>What should I do differently? <br>Again, thank you.<br>-- <br>View this message in context: <a href="http://osgeo-org.1803224.n2.nabble.com/Can-I-use-r-mapcalc-to-create-sorted-elevation-raster-tp5867462p5867462.html">http://osgeo-org.1803224.n2.nabble.com/Can-I-use-r-mapcalc-to-create-sorted-elevation-raster-tp5867462p5867462.html</a><br>Sent from the Grass - Users mailing list archive at Nabble.com.<br>_______________________________________________<br>grass-user mailing list<br><a href="mailto:grass-user@lists.osgeo.org">grass-user@lists.osgeo.org</a><br>http://lists.osgeo.org/mailman/listinfo/grass-user<br></div></blockquote></div><br><div> <span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>Malte Martin</div><div>----------------------------</div><div>+ 49 531 2258085</div><div>+ 49 177 3841416</div><div><br></div><div>Comeniusstr. 4</div><div>D-38102 Braunschweig</div><div>skype: maltehm</div><div><br></div></div></span></div></span></div></span><br class="Apple-interchange-newline"> </div><br></div></body></html>