Re: [GRASS-user] d.rast.arrows in high quality plot
Hi Nicolas, Thank you very much! The arrows are thicker now and are visible on the final plot. Cheers, Niklas Original-Nachricht Datum: Tue, 02 Nov 2010 23:26:01 +0100 Von: Nicolas Pérenne nicolas.pere...@free.fr An: Niklas Neckel nikn...@gmx.de CC: grass-user@lists.osgeo.org Betreff: Re: [GRASS-user] d.rast.arrows in high quality plot Hi Niklas, Same for me: the PNG driver draws thinner and thinner arrows when you increase the resolution. If you lower the resolution it's okay though. If you do need such a high resolution (for a poster?), you might try the CAIRO driver (g.manual displaydrivers) which behaves quite differently when producing PNGs. Arrows are drawn with a thicker pen indeed (even at high pixel resolution) but you might be surprised by the raster rendering... and files get very large. Nicolas Le mardi 02 novembre 2010 à 16:12 +0100, Niklas Neckel a écrit : Dear all, I'm trying to plot arrows, representing length proportional to magnitude in a printable high resolution map (with d.rast.arrows). Here is what I tried: #!/bin/sh export GRASS_WIDTH=1 export GRASS_HEIGHT=1 export GRASS_PNGFILE=testpng.png export GRASS_PNG_COMPRESSION=0 #export GRASS_RENDER_IMMEDIATE=TRUE export GRASS_TRUECOLOR=TRUE g.region fig_arrows d.mon start=PNG d.rast map=backgro...@permanent d.rast map=magnitude_...@permanent d.rast.arrow map=direction_...@permanent type=compass arrow_color=black grid_color=none x_color=black unknown_color=red skip=12 scale=20 magnitude_map=magnitude_...@permanent d.mon stop=PNG eog $GRASS_PNGFILE Unfortunately the plotted arrows are quite slim now... is there another solution to achieve this goal? Many thanks, Niklas ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user -- GRATIS! Movie-FLAT mit über 300 Videos. Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] v.buffer: circles around points
Hi Sharon, that sould be the radius, but: due to changing distances on latitude, the circle is not a true circle, as you can see when you reproject the map. The buffer distance is in degree. Hope, everything is correct, regards, Achim Am 03.11.2010 06:44, schrieb Sharon M: Hi, I'm starting to use v.buffer to create circles around points on Lat/Long vector maps. When entering a value for the distance parameter for v.buffer to create circles for points on lat/long maps, is the distance entered the radius of the circle or is it the diameter? or some other variable? Thanks in advance, Sharon ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Use of r.mode
Hi there, I have created a raster file from r.mode. It's a big image (is true) and it might me heavy but I'm not being able to get r.info information... In a 4GB RAM memory machine I have r.info raster and after 9 minutes It didn't printed anything. So I'm not being able to retrieve information from this raster. Any suggestion? Shall I create a copy of this file? and is this normal? Thanks Monica On Thu, Oct 21, 2010 at 11:32 AM, Monica Buescu monicabuescu1...@gmail.comwrote: Well, that's not good. Yes, maybe a problem with disk space or memory? l'll have to leave to someone more knowledgeable to answer here. Thanks Micha Probaby in this case is Memory space. Because for Smaller images I don't get any problem and bigger images I'm getting this problem. As anyone experienced such a problem? (GRASS takes too long to display an image or apply r.mapcalc? ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] Re: Deleting a signature file from a Script
Hi there, I have sent this email a couple of days ago. maybe no one nottest it :) has anyone implemented something similar in GRASS in a Python Script? 2010/10/29 katrin eggert katrineggert1...@gmail.com Greetings I need to have a script that automatically deletes a signature file associated with a designated group/subgroup. How can I do this from a Script? (e.g. Python) Thanks Katrin ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] r.out.pov scale question
Adam, find attached my (old) r.out.povscript script which does the needed calculations. Perhaps giving some ideas. the Povray scales are a bit tricky. cheers Markus On Wed, Oct 27, 2010 at 6:07 PM, Adam Dershowitz, Ph.D., P.E. adershow...@exponent.com wrote: I have been trying to use r.out.pov but something is not clear to me from the documentation, and examples I can find on the web. If I use hftype=0 (the default) then, as I understand it it, each step, from 0-65535 represents one map unit (meters in my case). That is giving me too much stair-stepping in POVRAY. I think that part of the issue is that there is too much rounding of elevations. So, I decided to try hrtype=1. As I understand it that will scale the height of the image to use more of the range (my map just goes from 61-1086 meters). But, I can't seem to figure out how much it scales by. There is also the scale= option in r.out.pov, but I am not sure if that is a multiplier or a divider? This is important because I need to then scale the heighfield in my POV file. If I use hrtype=0 then this is correct: scale dx, 65535, dy But, if I use hftype=1, what is the correct value for the above scale command? Is it 65535/1086 (max height in the map?) 65535/(1086-61) (vertical range of my map?) If I use scale=10 then should it be? scale dx, 65535/10, dy scale dx, 65535*10, dy scale dx, 10, dy Or should I use scale=0.1? Or should I use r.out.pov scale=65535/1086 Thanks, --Adam ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user r.out.povscript Description: Binary data ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] how to import idrisi vector map (.vct)
Hi everyone, I can't seem to find an answer to this (hopefully easy) one. How can I get an Idrisi vector map (.vct) into GRASS? Thanks a lot in advance, Márcia ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] Area weighting for vectors
Hi, I need to add some attributes from a soil polygon layer to a catchment polygon layer using area weighting. In other words, the contribution of the soil layer needs to be weighted by the amount with which its polygons overlap the catchment polygons. For example, suppose I want to weight soil infiltration rates. 30% of a catchment polygon overlaps with soil type 1 and 70% overlaps with soil type 2. Now I want a new attribute in the catchment polygon that takes 30% of the infiltration rate of soil type 1 and adds it to 70% of the infiltration rate of soil type 2. How can I do this in GRASS? Thanks Hanlie ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] r.out.pov scale question
Thanks. This is helpful for some ideas. Although, it uses a vertical scale that is just a constant of 65535. But, my followup email probably crossed with yours. --Adam On Nov 3, 2010, at 4:22 AM, Markus Neteler wrote: Adam, find attached my (old) r.out.povscript script which does the needed calculations. Perhaps giving some ideas. the Povray scales are a bit tricky. cheers Markus On Wed, Oct 27, 2010 at 6:07 PM, Adam Dershowitz, Ph.D., P.E. adershow...@exponent.com wrote: I have been trying to use r.out.pov but something is not clear to me from the documentation, and examples I can find on the web. If I use hftype=0 (the default) then, as I understand it it, each step, from 0-65535 represents one map unit (meters in my case). That is giving me too much stair-stepping in POVRAY. I think that part of the issue is that there is too much rounding of elevations. So, I decided to try hrtype=1. As I understand it that will scale the height of the image to use more of the range (my map just goes from 61-1086 meters). But, I can't seem to figure out how much it scales by. There is also the scale= option in r.out.pov, but I am not sure if that is a multiplier or a divider? This is important because I need to then scale the heighfield in my POV file. If I use hrtype=0 then this is correct: scale dx, 65535, dy But, if I use hftype=1, what is the correct value for the above scale command? Is it 65535/1086 (max height in the map?) 65535/(1086-61) (vertical range of my map?) If I use scale=10 then should it be? scale dx, 65535/10, dy scale dx, 65535*10, dy scale dx, 10, dy Or should I use scale=0.1? Or should I use r.out.pov scale=65535/1086 Thanks, --Adam ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user r.out.povscript ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] Re: Area Weighting for Vectors
Hi, I need to add some attributes from a soil polygon layer to a catchment polygon layer using area weighting. In other words, the contribution of the soil layer needs to be weighted by the amount with which its polygons overlap the catchment polygons. For example, suppose I want to weight soil infiltration rates. 30% of a catchment polygon overlaps with soil type 1 and 70% overlaps with soil type 2. Now I want a new attribute in the catchment polygon that takes 30% of the infiltration rate of soil type 1 and adds it to 70% of the infiltration rate of soil type 2. How can I do this in GRASS? Thanks Hanlie Hanlie, You would use v.overlay with operator=and to create a new vector that combines the two polygons. Then, add an area column to the new vector, and upload the area of the overlay to that column. You will also want columns to record the areas of the original two vectors (soil_area and catchment_area, for example). Use v.distance from your new polygon (from_type=centroid) to the original polygons (to_type=area and dmax=0) to upload the original areas into their respective columns. Also add a soil type column to the new polygon and, once again, use v.distance to record the soil type into the new polygon. You can then calculate percentages based on new_area/old_area. Richard ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
