QGIS is a user-friendly, cross-platform GIS application licensed under the GNU General Public License.

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2answers
209 views

Qgis 1.8 is not recognizing sdw file

I'm running qgis 1.8, and trying to load a sid file into my map. It imports fine, but seems to ignore the sdw file that comes with it, as the raster shows up without any apparent georeferencing. Is ...
0
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0answers
208 views

Hardware specifications for QGIS

New to QGIS, running on a Mac with adequate RAM & HD space. Looking to future I find no real hardware specifications. I want to find more information, can someone point me towards QGIS forum that ...
3
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0answers
73 views

How to analyze the signatures for a Landsat clasification with Sextante in Quantum Gis

I’m defining my training data for a Landsat classification. I´m digitalizing the polygons with the field data in QGis and I want to analyze the signatures of the Landsat images to avoid errors. In ...
7
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1answer
1k views

OpenLayers Plugin Error: latitude or longitude exceeded limits

I'm aware the 'traceback' OpenLayers plugin error has been dealt with before, so apologies for raising the issue once again. Unfortunately for me, the solutions posted were way over my head, e.g. ...
9
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2answers
416 views

Can I add an ArcToolbox tool to QGIS?

I have been using a publicly available tool in ArcGIS called SPreAD-GIS. It is a series of python scripts that are "implemented as an ArcGIS toolbox" (with tbx file). I am new to QGIS. Is there a ...
0
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1answer
176 views

Sextante grass folder incorrect?

What is the correct grass folder in Sextante? I alway get this message: The specified GRASS folder does not contain a valid set of GRASS modules. Please, go to the SEXTANTE settings dialog, and ...
14
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6answers
897 views

Can I transfer custom QGIS settings from one computer to another?

Can I export custom general settings from my QGIS installation to a file so that I can transfer the settings to QGIS on a different computer? Does QGIS have them already saved to a file located ...
0
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1answer
159 views

Saving part of OSM shapefile in QGIS as GeoJSON strips 'name' field to 25 characters long [duplicate]

I want to copy part of OSM data in ESRI Shapefile (downloaded from http://download.geofabrik.de/europe/ukraine.html ) and save in in GeoJSON to style later in Tilemill. After saving, I see that ...
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2answers
198 views

Is it possible to change a Geotiffs CRS?

Hi I have created a Geotiff from the Bing Aerial photography. As it is automatically in WGS 84 it inserts perfectly into QGIS, however this image is of no use to me outside of QGIS. I need to ...
0
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0answers
38 views

Why are areas of raster and polygon after digitization not matching? [duplicate]

I have followed the answer given in this question:How to calculate the area of rasters in QGIS? I vectorized and calculated the area using geometry columns but I a faced a strange problem. When I ...
1
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1answer
51 views

Removing Plugin Repository sites that fail to load

New here & to QGIS. Loading several plugins I noted that several sites seem to not load ( example "catais.org" or "GIS-LAB.info". Cannot actually find this site(s), I assume they are defunct, ...
1
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1answer
128 views

How to change delimiter in attribute table of QGIS?

I have imported a .kml file into QGIS, and the data is all shoved together into a single field like this: Fine, it's pipe delimited - easy to change the delimiter like in LibreOffice calc imports I ...
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0answers
349 views

How to calculate average value within a polygon(in Qgis with Python)?

Now I have a point and polygon shapefile and I want to calculate the points' average value within each polygons How to do it with python? I tried to find out but google gives me a lot of raster ...
1
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2answers
365 views

area values determined with field calculator become null when saving

using field calculator in Qgis 1.8.0 to get the area, it shows just right at first but when I save it, the values become Null. help please
1
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2answers
472 views

cannot see map in composer

Sorry if this is a repeat, but I couldn't find an answer here. And sorry if the answer is completely obvious, but I do appreciate your assistance with my first QGIS map. When I try to use composer ...
7
votes
1answer
153 views

How to save python session in QGIS?

After running a lot of scripts in QGIS' python console, I have more than 10 dictionaries and lists, and I need these for further analysis. Is there a way to save python session, with all these ...
1
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0answers
283 views

SAGA kernel density error with Sextante Modeler

I can succesfully perform SAGA kernel density analysis with Sextante (1.0.7) in QGIS 1.8.0. But i want to built an automated tool for this job with Sextante Modeler. But i got foolish errors. This ...
2
votes
1answer
54 views

why can I only define 6 custom CRS?

Using Q GIS 1.8.0 - I am trying to create several custom CRS definitions for the purpose of rectifying several split areas of a census shapefile. In the "Custom Coordinate Reference System Definition" ...
1
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1answer
44 views

QGIS - Importing USGS DRGs

I have asked about this before. If I import a USGS DRG raster for Anchorage, Alaska using EPSG:26706 - NAD27 / UTM zone 6N all the UTM coordinates are correct. Now if I want to look at the ...
1
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1answer
191 views

Sorting points with QGIS

I have a very good idea of what I would like to do but I really do not know if it is possible with QGIS. I have points that each one corresponds to a group size and I would like to use GIS to sort ...
0
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2answers
124 views

Query for Creating a buffer around a particular point

I am working on a project for ambulance management using GIS. using Qgis,Postgresql,Postgis I am finding it difficult querying using St_dwithin as well as St_buffer. My aim is to find any hospitals ...
4
votes
3answers
75 views

varying size of symbol depending on number of datasets

i am trying to map archaeological finds with qgis. some of them have the same coordinates since they are from the same site or very close to each other. is it possible to automatically display the ...
1
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1answer
137 views

I have detached the layer panel — how do I get it back to the side bar?

I accidentally clicked on the detach icon on the layer side panel and now it floats and I can not get it back to the side bar where I want it. There has to be a simple answer but I can't find it :(
2
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1answer
154 views

Why does QGIS 1.8.0 crash when I try to set up CRS on Win XP?

I have a problem with my qgis 1.8.0. When I click on any button that set CRS or try to set the coordinates on the fly, qgis crash. I try to uninstall the program and re-install it again using ...
3
votes
1answer
2k views

How to convert OSM relation xml data to shape file [closed]

I would like to transform the xml data here : http://wiki.openstreetmap.org/wiki/Berlin/Transportation into shape files or load into postGIS. I think the thing I am missing is how these xmls files, ...
1
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1answer
229 views

How to add MS SQL table using python console?

I have MS SQL Server 2008 R2 database. How to add MS SQL Table using python console in QGIS?
2
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1answer
198 views

Cannot find my schemas in QGIS's “Add PostGIS layers”

When I connect to my PostGIS database using QGIS's Add PostGIS Layers, I see only public topology pg_catalog information_schema My other schemas that I have created are not shown here. Anyone else ...
2
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0answers
108 views

Storing features in PostGIS and then creating layers using queries

I have a whole set of line segments or tracks that represent real tracks or, in some case, boundaries between areas. These segments form a network of lines on the map. I have a number of GIS layers, ...
3
votes
3answers
216 views

Can one load multiple GPX files at once?

I have a whole bunch of GPX files that I need to load into qgis and loading them one at a time using the GPS plugin is a bit painful. It will not allow one to select multiple files -- is there ...
2
votes
1answer
106 views

Join attributes by date in Qgis

I learned (thanks!) to use the join feature built into the layer properties, but in my case it doesn't work because data do not match perfectly. Infact shape refers to geotagged photos, csv is a log ...
1
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0answers
175 views

How can I move two layers at once in QGIS?

I'm trying to move two digitized layers, one containing points, the other polygons to a different location at the same time. QGIS doens't seem to allow this. Even if I select both layers and features ...
1
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1answer
73 views

How do I get a decent easy to use watermark from an image in Quantum?

Our users need to be able to put a graphic watermark onto maps they create in the print composer. Currently we get them to georeference the image as a raster and then create a transparency. This is ...
0
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1answer
334 views

qgis plugin: “WindowsError: [Error 6] The handle is invalid”

OS: Windows 7 64bit GIS: QGIS 1.8 (qgis.org/downloads/QGIS-OSGeo4W-1.8.0-2-Setup.exe) path variable: GISBASE=C:\Program Files (x86)\Quantum GIS Lisboa\apps\grass\grass-6.4.3RC2 ...
0
votes
1answer
394 views

Problems using v.split in SEXTANTE toolbox to split lines

I got this error: Or don't click "open output file after running algorithm", but there is no new shapefile created on my desktop. How to solve this problem and split lines at a specified distance? ...
0
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1answer
221 views

Using the API of QSpatiaLite plugin

I am using the popular QSpatiaLite plugin for QGIS. Since I am creating and modifying SpatiaLite tables directly with Python (using pyspatialite), I wonder whether I can automate tasks such as ...
1
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1answer
185 views

How to set the path to shapely?

I am using QGIS 1.8.0 on Mac OS 10.8.3 with python 2.7. Thanks to other threads in the forum, I have successfully installed shapely here: ...
3
votes
1answer
785 views

How to split line at a specified distance and getting coordinates of start and end points of each line segment?

I tried v.split in GRASS: and my notebook ran a lot of time but showed this error:bad allocation, then I click "OK", and got nothing. Are there other ways to split lines?and I hope to get 2 new ...
1
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1answer
45 views

Is there a way to traverse and select all vectors connected to a starting vector?

Preferably using QGis I'd like to remove errors from a road network .shp file and was wondering if there was a away to perform a flood fill or traversal on a vector layer to select all connected ...
4
votes
1answer
756 views

Why does Google satellite layer change the project CRS?

I have a project and a topomap in WGS84 (EPSG4326). On the fly CRS transformation is activated. I open Google satellite layer from the OpenLayers plugin. The Google layer is WGS84 / Pseudo Mercator ...
1
vote
1answer
399 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 ...
2
votes
1answer
40 views

Is it possible to always see all band values with Identify Features?

Does anyone know if it is possible to get the Identify Features tool in QGIS to show the band values for all the layers shown in the results window? To clarify, whilst I have several bands "showing" ...
0
votes
0answers
118 views

How to join edge of International Date Line in world file?

I am currently using world file (http://www.ngdc.noaa.gov/mgg/shorelines/gshhs.html) for international boundary information. Now I have difficulty with map projection that the map ends with ...
1
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1answer
66 views

How to identify to which polygon a point belongs to?

I have 3-4 polygons containing lots of lon/lat points. I want to identify to which polygon a specific point belongs. Any help in this matter is appreciated.
1
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0answers
150 views

How to fix “Error processing specified tolerance!” in Polygon Centroids tool?

I am using QGIS 1.8.0 to find the centroids of 92 features (i.e. smaller polygons) in a polygon layer. However, while using (Vector -> Geometry Tools -> Polygon centroids), I encountered the ...
0
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3answers
315 views

clipping polygons (vector) map with a polygon (vector) layer

A frustrated newbie with QGIS Lisboa version in Windows 7. I want to clip a soil map (multiple polygon vectors) with a single polygon (rectangular polygon vector). The project projection is set at ...
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0answers
358 views

GRASS Plugin to QGIS error

I am installing QGIS and GRASS as part of an FOSS GIS class I'll be teaching this summer. I used the OsGeo4W installer. This installer has always worked flawlessly for me except on the machines at the ...
1
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1answer
344 views

Problem to clip a raster with a shapefile

I need to clip a rasterlayer with a vector layer. When I try this, the following error appears: **ERROR 1: Attempt to create 0x0 dataset is illegal,sizes must be larger than zero.** What am I ...
2
votes
2answers
211 views

Data points Imported into QGIS are in the middle of ocean

I'm new to QGIS and tried importing some GTFS data in the CSV format (stops.txt). The project CRS, base map CRS and GTFS CRS have all been set to Google Mercator, but the points that are supposed to ...
1
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1answer
724 views

How to create a 3D shapefile from a raster?

I´m trying to make a 3D shapefile from a raster feature but not working. Tried already to run the command in OSGeo4W but nothing happen. I'm using the Qgis 1.8.0 Lisboa. The purpose is to get a final ...
1
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2answers
157 views

How to handle adding a PostGIS layer in pyQgis without saving password?

I'm writing python plugin and trying to find the right way to add PostGIS layer on the map without storing user password. After adding layer on the map, I strip out the password from uri like this: ...