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<div><br></div>Thank you Moritz, this worked beautifully!<br><br><div><div id="SkyDrivePlaceholder"></div>> Date: Mon, 7 May 2012 18:00:01 +0200<br>> From: mlennert@club.worldonline.be<br>> To: lee@isi-solutions.org<br>> CC: tanya.dyck@hotmail.com; grass-user@lists.osgeo.org<br>> Subject: Re: [GRASS-user] Euclidean distance (grow.distance) on raster to certain extent?<br>> <br>> On 07/05/12 16:36, Daniel Lee wrote:<br>> > Hi Tanya,<br>> ><br>> > I would use r.distance rather than r.grow.distance and then reclassify<br>> > the results to include only areas with <=1108 m distance - that should<br>> > be a lot easier.<br>> <br>> I don't think r.distance gives what you want, however r.grow.distance <br>> should be exactly your tool:<br>> <br>> As a starting point you need a raster map with all pixels in the orchard <br>> non-null and all other pixels null Let's call that raster map <br>> 'orchard'. Then you can do the following:<br>> <br>> r.grow.distance input=orchard distance=distance_map<br>> <br>> Then, if you only want to see the distance from the orchard to 1108m, <br>> then you can use r.mapcalc:<br>> <br>> r.mapcalc "final_distance_map=if(distance_map>1108, null(), distance_map)"<br>> <br>> All this keeping in mind that I don't understand what you mean by "I <br>> recognize this tool does not allow a distance to be included".<br>> <br>> If this means that you also want to measure a distance _within_ the <br>> orchard, then instead of using a raster map of the orchard, use as input <br>> to r.grow.distance a raster map with only the center pixel of the <br>> orchard non-null.<br>> <br>> Moritz<br>> <br>> ><br>> > 2012/5/7 Tanya Dyck <tanya.dyck@hotmail.com <mailto:tanya.dyck@hotmail.com>><br>> ><br>> > Hello,<br>> ><br>> > I am trying to run the grow.distance command to create a raster that<br>> > displays the euclidean distance from an 'orchard' outward to 1108m.<br>> > I am not trying to measure the distance between 2 non-null<br>> > features, but simply wish to have the euclidean distance extend out<br>> > from the orchard to 1108m. I recognize this tool does not allow a<br>> > distance to be included so I created a buffer around my orchard<br>> > (1108m) and intended to run grow.distance on that, however it<br>> > outputs the distance as if it includes the full raster extent (so I<br>> > have an output raster of 1108m that is all yellow as opposed to a<br>> > range of values displaying varying distances) and not limited to my<br>> > buffer. I want it to assume the buffer extent is the raster extent,<br>> > so to speak. Is there another way to do this?<br>> > Any ideas would be much appreciated.<br>> ><br>> > Best,<br>> ><br>> > Tanya<br>> ><br>> > _______________________________________________<br>> > grass-user mailing list<br>> > grass-user@lists.osgeo.org <mailto:grass-user@lists.osgeo.org><br>> > http://lists.osgeo.org/mailman/listinfo/grass-user<br>> ><br>> ><br>> ><br>> ><br>> > _______________________________________________<br>> > grass-user mailing list<br>> > grass-user@lists.osgeo.org<br>> > http://lists.osgeo.org/mailman/listinfo/grass-user<br>> <br>> <br></div> </div></body>
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