Re: [GRASS-user] Suggestion for creating a script to create a map of agricultural capacity
On 28/05/13 21:33, Glynn Clements wrote: But for this specific case, it's probably simpler to just generate an integer version of the slope map (if it isn't already) and use r.reclass, e.g. r.reclass input=slope output=slope.reclass rules=-EOF 0 thru 2 = 1 3 thru 5 = 2 6 thru 10 = 3 11 thru 15 = 4 16 thru 45 = 5 46 thru 70 = 6 * = 7 EOF Or keep the FCELL or DCELL and just use r.recode: r.recode input=slope output=slope.recode rules=-EOF *:2:1 2:5:2 5:10:3 10:15:4 15:45:5 45:70:6 70:*:7 EOF ? Moritz ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Suggestion for creating a script to create a map of agricultural capacity
Glynn wrote: But for this specific case, it's probably simpler to just generate an integer version of the slope map (if it isn't already) and use r.reclass, e.g. r.reclass input=slope output=slope.reclass rules=- EOF 0 thru 2 = 1 3 thru 5 = 2 6 thru 10 = 3 11 thru 15 = 4 16 thru 45 = 5 46 thru 70 = 6 * = 7 EOF note that r.reclass can read floating point maps too, but it's a bit buggy/weird, https://trac.osgeo.org/grass/ticket/1525#comment:10 Hamish ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Suggestion for creating a script to create a map of agricultural capacity
Hamish wrote: But for this specific case, it's probably simpler to just generate an integer version of the slope map (if it isn't already) and use r.reclass, e.g. r.reclass input=slope output=slope.reclass rules=- EOF 0 thru 2 = 1 3 thru 5 = 2 6 thru 10 = 3 11 thru 15 = 4 16 thru 45 = 5 46 thru 70 = 6 * = 7 EOF note that r.reclass can read floating point maps too, but it's a bit buggy/weird, https://trac.osgeo.org/grass/ticket/1525#comment:10 Right; r.reclass just generates the table, the actuall reclass is performed by lib/raster. If the base map is floating-point, it will be coerced to integer using its associated quantisation rules. Note that r.reclass doesn't pay any attention to the map's quantisation rules (even if it did, they could be changed between the reclass being created and being used, and the rules at the time of use would have effect). The buggy rounding code should probably be replaced with e.g. *v = (CELL) floor(fv + 0.5); or: *v = (CELL) ceil(fv - 0.5); or: *v = (CELL) (fv 0 ? floor(fv + 0.5) : ceil(fv - 0.5)); These differ on whether values lying exactly on a 0.5 boundary are rounded toward positive infinity, toward negative infinity, or away from zero respectively. The last one mimics the behaviour of C99's round() function. -- Glynn Clements gl...@gclements.plus.com ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Suggestion for creating a script to create a map of agricultural capacity
On 27/05/2013 22:36, Marcello Benigno wrote: Hi Micha, About: Not sure I understand the logic of taking the highest value This was defined by an agronomist, I also do not understand why =/ However, your answer is exactly what I need, did not know r.series, thank you! If you can help me also in this tip, I would be very grateful, I'm reclassifying the slope as follows: r.mapcalc class_1 = 'if(slope = 2.0, 1, null())' r.mapcalc class_2 = 'if(2.0 slope = 5, 2, null())' r.mapcalc class_3 = 'if(5 slope = 10, 3, null())' r.mapcalc class_4 = 'if(10 slope = 15, 4, null())' r.mapcalc class_5 = 'if(15 slope = 45, 5, null())' r.mapcalc class_6 = 'if(45 slope = 70, 6, null())' r.mapcalc class_7 = 'if(slope 70, 7, null())' r.mapcalc slope.reclass = class_1 + class_2 + class_3 + class_4 + class_5 + class_6 + class_7 How do I create a single _expression_ for this problem? How about using r.reclass ? Create a text file "slope_reclass.txt" which contains rows: 0 thru 2 = 1 2 thru 5 = 2 5 thru 10 = 3 ... 70 thru 100 = 7 then run r.reclass in=slope out=slope_rc rule=slope_reclass.txt Be aware that the reclass map is not a "real" raster. If you need to use it for other things, then a second r.mapcalc _expression_ will be necessary to create on on-disk raster map. Such as: r.mapcalc slope_reclass=slope_rc Regards, Micha Regards -- Marcello Benigno B. de Barros Filho Prof. do Curso Superior de Tecnologia em Geoprocessamento - IFPB Mestre em Cincias Geodsicas e Tecnologias da Geoinformao - UFPE Doutorando em Tecnologia Ambiental e Recursos Hdricos - UFPE http://profmarcello.blogspot.com http://about.me/marcello.benigno This mail was received via Mail-SeCure System. -- Micha Silver GIS Consulting 052-3665918 http://www.surfaces.co.il ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Suggestion for creating a script to create a map of agricultural capacity
Micha, Thank you very for helping me. Regards, -- *Marcello Benigno B. de Barros Filho* Prof. do Curso Superior de Tecnologia em Geoprocessamento - IFPB Mestre em Ciências Geodésicas e Tecnologias da Geoinformação - UFPE Doutorando em Tecnologia Ambiental e Recursos Hídricos - UFPE http://profmarcello.blogspot.com http://about.me/marcello.benigno ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Suggestion for creating a script to create a map of agricultural capacity
Marcello Benigno wrote: If you can help me also in this tip, I would be very grateful, I'm reclassifying the slope as follows: r.mapcalc class_1 = 'if(slope = 2.0, 1, null())' r.mapcalc class_2 = 'if(2.0 slope = 5, 2, null())' r.mapcalc class_3 = 'if(5 slope = 10, 3, null())' r.mapcalc class_4 = 'if(10 slope = 15, 4, null())' r.mapcalc class_5 = 'if(15 slope = 45, 5, null())' r.mapcalc class_6 = 'if(45 slope = 70, 6, null())' r.mapcalc class_7 = 'if(slope 70, 7, null())' 1. Note that a b = c is wrong; you need to use a b b = c. 2. You could optimise the above by using a single r.mapcalc command, e.g. (assuming Unix shell syntax): r.mapcalc EOF class_1 = if(slope = 2.0, 1, null()) class_2 = if(2.0 slope slope = 5, 2, null()) class_3 = if(5 slope slope = 10, 3, null()) class_4 = if(10 slope slope = 15, 4, null()) class_5 = if(15 slope slope = 45, 5, null()) class_6 = if(45 slope slope = 70, 6, null()) class_7 = if(slope slope 70, 7, null()) EOF This will generate all 7 output maps in one go, reading the input map only once (most r.mapcalc calculations spend more time reading and writing raster maps than performing calculations). 3. This: r.mapcalc slope.reclass = class_1 + class_2 + class_3 + class_4 + class_5 + class_6 + class_7 will result in an all-null map, as arithmetic operators return null if either input is null. Changing the null() with 0 in the calculation of the class_* maps would fix this, or you could just use r.patch instead of r.mapcalc. Sticking with r.mapcalc, it would be simpler (and more efficient) to generate the output map directly from the input, without generating any intermediate maps, e.g.: r.mapcalc EOF slope.reclass = \ if(slope = 2, 1,\ if(slope = 5, 2,\ if(slope = 10, 3,\ if(slope = 15, 4,\ if(slope = 45, 5,\ if(slope = 70, 6,\ 7)) EOF [The above could be written on one line, but splitting the expression with backslash-newline improves legibility.] But for this specific case, it's probably simpler to just generate an integer version of the slope map (if it isn't already) and use r.reclass, e.g. r.reclass input=slope output=slope.reclass rules=- EOF 0 thru 2 = 1 3 thru 5 = 2 6 thru 10 = 3 11 thru 15 = 4 16 thru 45 = 5 46 thru 70 = 6 * = 7 EOF -- Glynn Clements gl...@gclements.plus.com ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Suggestion for creating a script to create a map of agricultural capacity
On 27/05/2013 16:41, Marcello Benigno wrote: I'm working on the preparation of the statement of Agricultural Capacity in general terms the final map has classes ranging 1-8. To get this map I use three themes with their respective notes: Map of Slope: with classes ranging 1 to 8; Soil Map: with classes ranging 1 to 8; Map of flood risk: with classes ranging 1 to 8; I - After converting all to a vector format and "merge" the three layers, I have multiple polygons with various combinations, eg: a) 1,3,1 b) 5,2,1 c) 4,2,1 d) 1,1,8 II - To determine the final value of the class is chosen the highest value: a) 3 b) 5 c) 4 d) 8 Not sure I understand the logic of taking the highest value, but you can do this simply with the original rasters using: r.series input=slope,soils,floods out=agri_risk method=max Then convert to vectors only at the end. I need to automate this task because the last step (II) is very slow (actually manually), which would be the best way to do this? I think the whole process can be done with the data in raster format, but have not found a formula that I can apply in r.mapcalc to this problem. Thanks in advance, -- Marcello Benigno B. de Barros Filho Prof. do Curso Superior de Tecnologia em Geoprocessamento - IFPB Mestre em Cincias Geodsicas e Tecnologias da Geoinformao - UFPE Doutorando em Tecnologia Ambiental e Recursos Hdricos - UFPE http://profmarcello.blogspot.com http://about.me/marcello.benigno This mail was received via Mail-SeCure System. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user This mail was received via Mail-SeCure System. -- Micha Silver GIS Consulting 052-3665918 http://www.surfaces.co.il ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Suggestion for creating a script to create a map of agricultural capacity
Hi Micha, About: *Not sure I understand the logic of taking the highest value * This was defined by an agronomist, I also do not understand why =/ However, your answer is exactly what I need, did not know r.series, thank you! If you can help me also in this tip, I would be very grateful, I'm reclassifying the slope as follows: r.mapcalc class_1 = 'if(slope = 2.0, 1, null())' r.mapcalc class_2 = 'if(2.0 slope = 5, 2, null())' r.mapcalc class_3 = 'if(5 slope = 10, 3, null())' r.mapcalc class_4 = 'if(10 slope = 15, 4, null())' r.mapcalc class_5 = 'if(15 slope = 45, 5, null())' r.mapcalc class_6 = 'if(45 slope = 70, 6, null())' r.mapcalc class_7 = 'if(slope 70, 7, null())' r.mapcalc slope.reclass = class_1 + class_2 + class_3 + class_4 + class_5 + class_6 + class_7 How do I create a single expression for this problem? Regards -- *Marcello Benigno B. de Barros Filho* Prof. do Curso Superior de Tecnologia em Geoprocessamento - IFPB Mestre em Ciências Geodésicas e Tecnologias da Geoinformação - UFPE Doutorando em Tecnologia Ambiental e Recursos Hídricos - UFPE http://profmarcello.blogspot.com http://about.me/marcello.benigno ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
