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2answers
68 views

Extract Elevation of Points from DEM using Python QGIS or GRASS

I am utterly new to GIS, so please bear with me if I am providing incomplete information here. I have a DEM file (.dt2). What I am looking to do is as follows: take a series of points specified as ...
0
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0answers
15 views

r.watershed outputs different depending on use of console and toolbox

I am returned two different outputs despite same input parameters from r.watershed depending on whether I run it from the console or from the GRASS toolbox. The threshold for both is 5000. They both ...
3
votes
0answers
77 views

Extract representative slope profiles from hillslope polygons

With the help of the Whitebox Geospatial Analysis Tools I was able to easily extract hillslopes from a river network in combination with a flow direction map. Now I would like to extract ...
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1answer
43 views

How to fix this “Sorry <1> is not a valid option” in GRASS-Ubuntu using r.water.outlet?

I am working with this .sh code (a while loop, extracted from: http://www.surfaces.co.il/) to create watersheds from drainage raster and outlet point of every watershed, but I obtain this error: ...
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0answers
54 views

Python script split up

I have a python script which works with Grass 6.4. At some point during the project I decided to split this big python script into several scripts. I have made all necessary variables global, created ...
1
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1answer
116 views

GRASS scripting for producing multi-band raster

I am trying to loop the r.sun function within a Python script. Anyway, I seem not to understand how I can stack the raster maps each loop would produce into a single multi-band raster (preferably in ...
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2answers
117 views

Problem with Bash loop in GRASS GIS

I'm new to GRASS GIS and programming and I'm running into a lot of what I imagine are beginners problems and something similar to this has been asked before, but not In a way that I understand. I'm ...
2
votes
1answer
91 views

How to use grass.script in MacOS

I have installed Python and Grass6.4 using Macports. When I tried to use "import grass.script" in python environment, it gives "no module found" error. I'd spend much time to fixed it but could not ...
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0answers
52 views

r.walk: Incorrect cost parameter values on GRASS GIS Windows version 6.4.3

GRASS GIS 6.4.3 (MS Windows OS): When I run r.walk (from command line), the cost parameters (a,b,c,d) come back like this: Walking costs are a=0.000000 b=-0.000000 ...
1
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1answer
110 views

How to batch-process attribute tables in QGIS (or GRASS)?

I'm using GRASS 6.4.3 in Linuxmint 16. I have a bash script for GRASS which I use to process almost 300 raster files. The script first imports some raster files (r.in.gdal), then does some ...
1
vote
1answer
19 views

Is my code for changing the resolution correct?

I have a raster files of daily minimum temperature (tmin) for the period 1962-2011 at a resolution of 1.125. I need to convert each single day raster file into 0.5 using inverse distance ...
1
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0answers
101 views

GRASS and r.viewshed

I'm trying to run the r.viewshed command using co-ordinates held in a .csv file I imported using v.in.ascii. It has over 200 rows and I'm looking to run viewsheds from each line, without doing it ...
0
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1answer
262 views

How to use python to set a variable to a value from a vector attribute table for GRASS

I'm adding to a python script for GRASS v.transects.py. I want to set a variable to equal a value from a field in the vector's attribute table using a for loop to cycle through each row. This is one ...
0
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0answers
163 views

How to process multiple images in Grass GIS

first of all, I have to mention that I'm almost new working with Grass and I'm using Grass 6.4.3 on Linuxmint 16. I need to process a large number (~300) of Landsat images. I have downloaded the ...
0
votes
0answers
74 views

Run this module in GRASS 6.4.3 command line in Windows 7 or QGIS Grass Module

I have GRASS 6.4.3 running and working in windows. I would like to use this script (http://grasswiki.osgeo.org/wiki/AVHRR) Scroll down to Import to see the code. I have the correct EPSG set but ...
0
votes
1answer
22 views

Problems installing r.roughness

I am trying to install r.roughness in GRASS 6.4.3. It starts compiling but at the end I get this error: ERROR: Module did not install properly I cannot identify the problem. Can somebody that has ...
1
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3answers
770 views

Problem with python script to control GRASS GIS from outside - How to import grass.script under Win 8.1?

I am working with GRASS 6.4.3 and python 2.7.6 under WIN 8.1. I am a novice with computer science and coding, and I have seen many posts including those:Is it possible to use GRASS GIS in Python ...
1
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1answer
141 views

Can one batch-automate the creation of QGIS heatmaps?

I have 4k point shapefiles, from which I would like to generate heatmap TIFFs using the QGIS heatmap plugin (or a functional equivalent featuring triweigth, radius and cell size selection). Is there ...
2
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2answers
245 views

How to do the loop when using GRASS module r.water.outlet?

I have seen this post:Watershed Analysis with GRASS, and I have a .txt file which contains coordinates of many points, and I want to use r.water.outlet to get basin area of each point. I type the ...
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0answers
73 views

Is there any GRASS command to measure the distance between a point in rastermap and another in vector map?

I have a question about WinGRASS 6.4.3. Is there any GRASS script command to measure the distance between a point in rastermap and another in vector map? I have a raster map and a vector map. Raster ...
0
votes
1answer
401 views

d.rast problem in GRASS command line

Update#1: @gene, thank you for your reply and I type d.mon in command line, getting a popout GUI look like this: I choose the top three flags(-l, -L, -p), and I got this: And I don't know what to ...
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1answer
120 views

g.list problem in GRASS command line

I am using GRASS 6.4.3 (installed with osGeo4w), and I have this question: As I type g.list, a function window will pop out, and all functions and results are fine. But when I type g.list rast, I got ...
1
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1answer
177 views

libfreetype-6.dll lost when using GRASS command line

Update#1: Following the instruction of Sorin Călinică, I have installed libfreetype-6.dll using the OSGeo4W Network Installer, and the command d.rast can launch successfully. I am using GRASS ...
2
votes
1answer
214 views

How to iterate GRASS region definition?

I am using GRASS r.skyview command (v.7, Windows) to determine "urban canyon effect" on pollution due to the presence of buildings. The command nicely works, unfortunately I need to process a very ...
1
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0answers
31 views

GRASS 6.4.2 define Geographic boundaries using MSYS

I am working with daily gridded rainfall data of 50 years. The initial data had the extension .nc.gz.tar which I have unzipped using MSYS in GRASS 6.4.2. Now I have 365*50 days of daily data. My ...
1
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1answer
163 views

Set Grass Region in Python grass.script

How can I set the Grass Region in Python without already having a map in the Mapset? Basically I am looking for the equivalent to this window Currently I am only able to extent an existing region, ...