Hi Pedro, Thank you very much for the explanation. That helped me to get a basic idea of what these files do. Then what I did was to change these files. I changed some records in wind speed and wind direction (the files in demomapset/cats). But what I observed was there was no change in the shape of spread even after the alterations. Is there anyone who willing to help me in crating custom files if I provide the relevent information. I need to crate wind, moisture, and fire origin files.
BR, Vidura Dantanarayana. On Sat, Sep 1, 2018 at 7:23 PM Pedro Venâncio <[email protected]> wrote: > Hi Vidura, > > You need to prepare the input data to r.ros algorithm > > https://grass.osgeo.org/grass74/manuals/r.ros.html > > The input data needs to be in raster format. > > First you need to use the standard NFFL 13 fuel models system ( > https://www.fs.fed.us/rm/pubs/rmrs_gtr153.pdf) as fuel model input raster. > > You also need the fuel moisture content for all sizes and response times > (dead 1h, 10h, 100h and live), in percentage. > > As Moritz explained to you, you can see that the 1hour_moisture raster of > the sample data is composed by: > > - 3% moisture in areas of fuel model 4; > - 15% moisture in areas of fuel model 8. > > You can give homogeneous fuel moisture content for each response times, or > different if you have that information, like in the sample data. > > Then you need an elevation raster (DEM), calculate slope and aspect (if > you don't have them yet, with r.slope.aspect), and a raster with wind speed > (in feet/minute) and another with wind direction (clockwise from north, in > degrees). > > With this data, you run r.ros and with the output rasters, run r.spread > > https://grass.osgeo.org/grass74/manuals/r.spread.html > > r.spread just need the an additional raster, with the ignition(s)/starting > sources. Pixels of starting sources raster needs to be only values of 1 > (ignition points/areas) and 0 (other areas). If you have the ignitions in > vector format, just use v.to.rast. > > I hope this helps. > > Best regards, > Pedro Venâncio > > > > Vidura Dantanarayana <[email protected]> escreveu no dia sábado, > 1/09/2018 à(s) 14:12: > >> Hi all, >> >> Thank you very much Moritz Lennert for the explanation and apologize for >> the mistake I've done. I will try what you suggest by myself. Hope It's >> okay to questioning again if I found a problem again. Have a wonderful day. >> Cheers!!! >> >> BR, >> Vidura Dantanarayana. >> >> On Sat, Sep 1, 2018 at 2:04 AM Moritz Lennert < >> [email protected]> wrote: >> >>> Hi Vidura, >>> >>> First of all, please keep discussions on the list. >>> >>> On 31/08/18 09:48, Vidura Dantanarayana wrote: >>> > Hi Moritz, >>> > >>> > Really appreciate your help as we are facing this problem for some >>> days >>> > now. First I'm a beginner user. Can you explain what are the >>> categories >>> > and how those used in GRASS GIS? >>> >>> GRASS GIS is an extremely wonderful and powerful tool, but it does need >>> some initial learning in order to understand how to use it. Just >>> answering the questions below will not provide that for you. >>> >>> I would suggest that you go through some of the basic introductory >>> material, just in order to get a feeling for GRASS GIS, before attacking >>> your specific problem. >>> >>> You could have a look at the following resources (at least for their >>> introductory parts): >>> >>> - https://grass.osgeo.org/grass74/manuals/helptext.html >>> - https://grass.osgeo.org/grass74/manuals/rasterintro.html >>> - https://grass.osgeo.org/grass74/manuals/vectorintro.html >>> - >>> >>> https://grasswiki.osgeo.org/wiki/From_GRASS_GIS_novice_to_power_user_(workshop_at_FOSS4G_Boston_2017) >>> - >>> >>> http://www.training.gismentors.eu/isprs-summer-school-2016/lesson1/grass-gis.html >>> >>> Or search for "GRASS GIS" in YouTube for some videos. >>> >>> > Let's say I need to create custom >>> > 1hour_moisture (or any other file), so how can I create these files? >>> >>> How you create these files depends on the data that you have as input. >>> >>> If you look at the metadata of the file in the demolocation >>> (right-click->Metadata or 'r.info 1hour_moisture' you will this >>> information at the end: >>> >>> | Data Description: >>> | >>> | generated by r.mapcalc >>> | >>> | >>> | >>> | Comments: >>> | >>> | if(fuel_class==4,3,if(fuel_class==8,15)) >>> >>> >>> This means that the authors had a raster file called 'fuel_class' and >>> used the raster calculator (r.mapcalc) to reclass that file attributing >>> the value 3 to those pixels who had class=4 in the original map and >>> value 15 to pixels with class=8. >>> >>> I have no idea what this original map contained, so cannot help you >>> further (I don't know much about fire spread modeling). >>> >>> > Can >>> > you look at the following problem again? >>> > >>> > >>> > # 1 categories -----------------------------------------------------> >>> (1) >>> > Map of Fire Origin of Bass River Fire --------------------> (2) >>> > >>> > 0.00 0.00 0.00 0.00 ---------------------------------------------> (3) >>> > 0:no data -----------------------------------------------------------> >>> (4) >>> > 1:fire origin >>> ---------------------------------------------------------> (5) >>> > >>> > I need to know how to customize the location of origin. I mean, I want >>> > to ignite the fire from another place rather the place specified in >>> demo >>> > data. >>> >>> If you have the origin location as coordinates, you can create a vector >>> point at the location using v.in.ascii: in the GUI of that module you >>> can enter coordinates interactively. Then you convert the map to a >>> raster map using v.to.rast. >>> >>> Moritz >>> >> _______________________________________________ >> grass-user mailing list >> [email protected] >> https://lists.osgeo.org/mailman/listinfo/grass-user > >
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