GRASS GIS (Geographic Resources Analysis Support System) is a free, open source geographical information system (GIS) capable of handling raster, topological vector, image processing, and graphic data.

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Loading GRASS gives error installing QGIS Chugiak on Windows 8.1?

I am experiencing a problem installing QGIS 2.4 Chugiak on Windows 8.1, resulting in a error loading Grass. This may be a problem only affecting certain installations, I'm not sure. I am a noob on ...
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18 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 ...
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65 views

How to modify existing grass gis tools and run them in QGIS?

I would like to take an existing tool of the grass tool box and modify the code to the specific needs of my task. As I´m struggling to start some kick-off would be great. How to access code? What do I ...
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126 views

Empty signature file after i.gensig in GRASS

I'm trying to make a supervised classification in Grass 6.4.3 under Linuxmint 16. After digitizing the training areas, I transformed them from vector to raster. Then I've done the following: just in ...
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1k views

“Missing dependency.This algorithm cannot be run :-(” QGIS + GRASS Windows 7

Windows 7, OsGeo4W pack installed including QGis 2.4.0 and GRASS. I Qgis when i try to execute a GRASS geoprocessing algorithm i get this popup: "Missing dependency.This algorithm cannot be run :-( ...
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113 views

GRASS GIS: auto-completion fails in commande line

I'm running GRASS GIS 6.4.3. on Win 7, SP1, 64 bit. The path to my grass-DB is: D:\grassdb Within the GRASS GIS Commande Line, if I press the tab-key to auto-complete only folders, files and ...
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35 views

GRASS GIS 3D - Inconsistent number of attributes

I am trying to automate my 3D plotting of GRASS GIS 7 results, also to make them more consistent in size and view angles. So for m.nviz.image elevation_map=DEM -a mode=fine resolution_fine=1 ...
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47 views

Problems running grass.mapcalc

I am using the GRASS Python Scripting Library on Ubuntu 14.04 with the packages available from the Universe repository. I have the following block of code: try: ...
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60 views

Combining several rasters before r.surf.contour?

I have been trying to generate an elevation model from contour lines using first v.to.rast.attr and then r.surf.contour. Generally, it works pretty well, execpt for one issue. My data contains a lot ...
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87 views

How to batch interpolate many shp´s to DEM

Here´s the problem: I have about 40 shapefiles of contourlines (type line) and I need to interpolate them to create DEM's (tiff, or better some grid format). To do so, some batch scripting would be ...
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237 views

Create a common scale for different raster layers in GRASS, SAGA or QGIS

I have a number of layers that represent the temperature variability of the water in a lake. They have been generated trough interpolation and have different values as they represent temperatures ...
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72 views

How to mask the images in GRASS

I have MODIS NDVI images, which needs to be masked with VI_Quality. I am using GRASS software and executing GRASS commands using shell scripts. I need to perform raster calculation (multiplication) ...
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100 views

How to number points along a line consecutively

I have a line and along this line I have different points which are max. 20m away from that line. Now I would like to number the points along the line, like shown in the grafic. Any suggestions how to ...
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114 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 ...
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314 views

How to make GRASS and SAGA tools capable to use in QGIS?

As my title, I installed Qgis, GRASS and GDAL by osGeo4w package, and as I finish the installation, I want to use GRASS tool, I face this problem: But I already installed GRASS and SAGA, how to make ...
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87 views

Is there a tool to buffer features with more than one distance value in GRASS GIS?

I´m looking for a tool like Multiple-Ring-Buffer in ArcGIS, but for GRASS GIS to be able to buffer with different distances but only having to start the process once.
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369 views

When trying to convert an .e00 file into a shapefile with ogr2ogr, getting “ERROR 4: This looks like a compressed E00 file”

When I ran this command: ogr2ogr topo.shp flowe86hyp.e00 I got this error: ERROR 4: This looks like a compressed E00 file and cannot be processed directly. You may need to uncompress it first ...
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280 views

How to get additional subbasin areas designated by points in the river network?

Update 14/1/9:I follow this post:Watershed and Stream Network Delineation, and here's my workflow: use Batch Point Generation to create batch points related to designated points(green dots) Batch ...
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494 views

Calculate distance of points along a route QGIS

I have a line layer and a point layer, I need the distance between the first and the last point measured along the line. How can I do that using QGIS? Do I need to know linear reference? I don't ...
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515 views

What is the best way to ortho-rectificate image from the plane?

I am very new in GIS and I am trying to ortho-rectificate my images. But after putting it on the map I see that results are not precise. We have images taken from the airplane, it's longitude, ...
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229 views

No such file or directory PERMANENT\\MYNAME from Python+Grass?

I have an existing Python script that processes raster images with Gdal / Numpy. Now I want to extend the script with Grass. The python script is developed on Windows 7 with Eclipse/Pydev. The script ...
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179 views

How to compare accuracy of two DEM using GRASS

How do I compare accuracy of two DEM data (lidar and srtm) (possibly through rmse) using GRASS GIS? thanks
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134 views

How to set opacity for GRASS layers using command line?

In the process of learning GRASS, I am finding that I can learn many of the command-line methods that I need for scripting tasks from using the wxGUI, as it conveniently shows most of the underlying ...
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2answers
102 views

Neighborhood analysis based on occurrence of value

How can I do, either in ArcGIS, grass or another tool, the following: for each cell (pixel), if there is at least one cell with value '4' in a neighborhood of 5 cells around it, reclassify that cell ...
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359 views

How to debug “Unable to load GDAL library” error in QGIS 2.0?

I have a problem with r.surf.contour. I create a DTM with v.to.rast.attribute and then use the r.surf.contour and it works fine in QGIS 1.9 but with QGIS 2.0 doesn't work. I have a contour shapefile ...
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107 views

Calling GRASS 6 in GRASS 7 (shell)?

I am running a shell script for batch processing in GRASS 7 (calling it with sh [...sh] in the command line window), which creates a series of rasters through classifications, raster calculator and ...
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153 views

create POV-Ray image from DEM-file in grass

I am working on r.out.pov Tool of grass 6.4 creating a POV-ray(beautiful 3D) image from an elevation raster. You can see this link for more information about 3D analysis of GRASS. r.out.pov manual ...
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783 views

Using Landsat 8 for quantitative analysis - what DNs does GRASS require?

Hoping someone can short circuit a lot of exploration Landsat 8 values are stored as unint16 since the sensors work on a range 0 to 4096 whereas the L7+TM was 8 bit and had a digital number range 0 ...
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107 views

GRASS 6.4.3 Landsat processing

what are the pre-processing steps required for landsat etm+ with GRASS 6.4.3 prior to land cover change detection? The product used is L1T.
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206 views

Importation of .csv on grass gis converts numeric data to string data

When importing a csv file on grass7, the numeric data is converted into a data of type string. My csv looks like this : id_core value 1 F1 83.0611472396 2 F2 98.8584345936 3 F3 ...
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123 views

Use of Grass and R w.r.t. Land Use Prediction

In my data mining term project I need to conduct a work on geospatial data related to a big city to show possible urbanization fields in next years. I've used GRASS lately on other projects so I'm a ...
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204 views

Grass 6 extension installation in Grass 7 error

I am trying to install the extension r.roughness from the Grass 6 repository, but in Grass 7. When trying g.extensions, the error "make: * No rule to make target ...
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193 views

Add-ons on GRASS (win7)

Can someone help me to install an add-on for GRASS 6.4.3RC3, on Windows 7? I tried several approaches, but wasn't able to install the add-on. I found several topics here and on the web but the ...
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200 views

contour lines from point shape attribute

I have a point shape file and one of the attribute refers to the altitude. Is is possible to obtain a contour lines shape file in GRASS?
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57 views

GRASS: shift point locations in a random direction

I have a vector map that contains 100 points. For each point, I would like to shift it 250 units in a random location. It's easy enough to shift all points in a specified direction using v.edit ...
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553 views

import grass.script as grass under windows 7

OS: Windows 7 64bit GIS: QGIS 1.8 (qgis.org/downloads/QGIS-OSGeo4W-1.8.0-2-Setup.exe) I have created a plugin for QGIS, with the QGIS plugin builder. Now i would like to import grass.script into ...
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818 views

QGIS, Euclidean distance analysis [duplicate]

i wanna generate euclodian distance map for my road data. I 'll use it for multi criteria analysis. I can get it by using Arcgis Euclodian Distance tool but i wanna generate it in QGIS environment. I ...
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162 views

How to remove terracing from Civil3D GeoTIFF export?

I've received a GeoTIFF DEM that was exported from Civil3D and at every contour there is a distinct terrace created when I process an aspect or slope in QGIS with the GRASS plugins. I've looked ...
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320 views

Installing GRASS on MINT 14?

I'm very new to mint/linux/GRASS and have no clue how to deal with these errors. Can I just change the URL somewhere? Here is the simplest reproducible command to produce a failure: sudo apt-get ...
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123 views

Set certain amount of pixels to 1 inside of a polygon (GRASS)

I have a rather coarse vector map with polygons and want to calculate a (sufficiently) finer raster map defined by spatial extension and resolution. Every polygon of the vector map has a value ...
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210 views

Why is transparancy of GRASS rasters missing when imported into QGIS?

I have a raster map in QGIS imported from a GRASS mapset with the QGIS GRASS plugin. The problem is that I have null() cells in the GRASS map that appear "colored" in QGIS. How can I set the ...
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84 views

Hydrograph in GRASS

How to make hydrograph for a basin in GRASS? While surfing the GRASS home page, I came to know that some time back in GRASS 4.x a command r.water.fee exist. I understand, it is missing in GRASS 6.4. ...
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115 views

How to extend lines in Grass

I have a set of vector lines in grass which I need to convert into polygons. However, because of bad base data, the polygons don't always close. To fix this, I need to extend each disjointed line by ...
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646 views

Python script for GRASS - executing from PHP

I wrote the following python script: #!/usr/bin/env python import os import sys gisbase = os.environ['GISBASE'] = "/usr/lib/grass64" gisdbase=os.path.join("PATH") location=LOCATION NAME ...
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4answers
503 views

Determining gradient of road segment

I've a shapefile of roads data. It contains information about terrain of road segments, i.e., hilly, flat, undulating, etc. I want to determine gradient of every road segment. I know this might ...
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77 views

Is there a way to access ps.map in python?

i am wondering whether its possible using python interface to load layers and edit them in Print/Cartographic Composer without displaying, and finally export to PDF? something that can be done via ...
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236 views

v.dissolve renames the attribute table column and does not produce a dbf

When I run v.dissolve on my vector... v.dissolve --o input=pass2@mapset1 layer=1 column=fttcp output=pass3 The dissolving appears to work but the column name in the attribute table has changed from ...
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494 views

r.sim.water G_malloc error

I've been trying to run r.sim.water on a 3 meter LiDAR-generated DEM I have, but keep getting G_malloc errors: r.sim.water --verbose elevin=meterDEM.final@Sediment_Simulation ...
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290 views

Automatically apply topology rule to only selected portions of a .shp file?

I am looking for some examples/tutorials on how to apply a topology rule to only a selected portion of a shp file using a script in ArcGIS/GRASS. Using ArcGIS seems to always require an interactive ...
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135 views

Blank Vector Selection Dropdown in QGIS GRASS Plugin

I realise there are some issues which getting vectors into the GRASS module in QGIS, but is the behaviour i am getting expected? I have loaded the vector shapefile via GRASS, closed G and reopened ...