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

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Sextante Modeler Error “global name os is not defined” [duplicate]

I want to generate a model whic reclassify radter values. So i added Saga reclassify grid values tool to Modeler and saved the model. When i run the model i got this error both on Ubuntu OSgeolive 6.0 ...
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1answer
116 views

In QGIS can I show just the lines in a Postgis query? How can I do that?

I have three tables in Postgresql, each table with one layer of lines. I want to show the path of an initial line to another final. Is it possible executing a SQL query? Thanks My three tables are ...
0
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2answers
291 views

Why is QGIS reading in my CSV numeric data as string data, and how do I change it? [duplicate]

QGIS keeps reading in my numeric data from .csv files as string data. This means I have to figure out how to read it in with the proper data type, or convert it back to numeric inside of QGIS, ...
2
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3answers
253 views

How to delete polygons less than a certain area?

I'm trying to delete all polygons with an area smaller than a certain give value. Is this possible in qgis? The goal here is to delete all the islands off a map.
3
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2answers
161 views

Why is it so hard to download only a part of OSM data by attribute tag?

Is there any online service that allows to download only one thematic layer of the OSM data for a specific geographic region? For example all objects related to vegetation (trees, grassland,...), but ...
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2answers
343 views

SAGA, GRASS Raster values to null

I want to make the cells which values "1" to null in QGIS with Grass or Saga tools (exactly Saga).
0
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1answer
88 views

Is it possible to export an image that can be zoomed-in on?

I am using QGIS on a Mac. I would like to export my map so that the viewer can zoom in on it, just as I view the map on my QGIS canvas. I am not sure how to word what I want. If you see the map ...
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0answers
39 views

Print Composer doesn't display my map! [duplicate]

So I have created a map that I need to share with my coworkers. When I open Print Composer and add map, my map does not appear in the rectangle that I create. It is just blank. I try updaing the ...
8
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5answers
2k views

What is the best free web GIS browser?

Hi I have created several projects for several different clients. Each project has OS maps, shapefile layers from Government Bodies, Shapefile layers created, AutoCAD dxf loaded in (in various ...
2
votes
2answers
173 views

merging layer stored in PostGIS

I have a bunch of layers stored in PostGIS that I want to merge. I have spent quite some time investigating various approaches but I ket tripping over getting the GIDs to update properly. In the end ...
1
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0answers
509 views

Line to Polygon via Polygonizer in QGIS

My question is in the same vein as this one. I'm attempting to convert precipitation lines (Precipitación Media Anual) to a polygon for Mexico in QGIS using the Polygonizer plugin. After running the ...
0
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1answer
240 views

QGIS Trace Tool; Error

I have installed the traceDigitize tool from the experimental repository in QGIS 1.9.0 Lisboa. My understanding of the tool is that you have to: Add 2 layers to QGIS Desktop. My empty shapefile to ...
2
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2answers
204 views

How to determine the coordinates of the corners of the raster layer

How can we determine the coordinates of the corners of the raster layer? The image opens function QgsRasterLayer.
8
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3answers
919 views

Howto setup and use a remote GIS workstation (QGIS,GRASS,PostGIS)?

I'm using QGIS (and sometimes GRASS and PostGIS) on my 2009 MacBookPro for my thesis project. I was wondering (during an endless batch generalizing in QGIS) if I can set up a server so I can work from ...
1
vote
1answer
75 views

Is there any “proper” way of setting the viewport for QGis Time Manager?

I'm working on video visualisation for some geo data. Everything works fine for me except the viewport that the time manager plugin is using for image frames. It makes image frames size of actual map ...
9
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1answer
293 views

How to find the buildings (polygons) a user can see from a given location (point) and orientation (angle range)?

I would like to retrieve the set of buildings I can see from a given location (point -lat,lng) and orientation (interval of angles) + certainly with a given depth (e.g. 100 meters). Ideally I would ...
2
votes
2answers
447 views

How to calculate area in sq km of an ellipsoid shapefile

In QGIS, I often find myself setting up projects with an ellipsoid coordinate system (e.g. WGS84) so that the resulting maps have lat lon scales, etc. Often in these projects I also need to do some ...
3
votes
2answers
2k views

How to reclassify a float raster?

I have three rasters which represent distance (in metres) from certain things (bus stops, parks, libraries). I would like to reclassify these rasters so that they get integer values based on the ...
0
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1answer
78 views

Full Easting and Northing coordinates values cannot be encoded in GRASS r.water.outlet in SEXTANTE-QGIS

The Easting or Northing coordinate parameter accepts only 5 digits. The Easting and Northing values for my outlet are 6 and 7 digits long (integer). How can they be encoded in r.water.outlet? Can ...
3
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0answers
371 views

Error in uploading data in QGIS cloud

I want to publish my .shp file using QGIS Cloud plugin. I signed in to qgiscloud.com (free). On create new database it will auto create dbname='fbeudp_mfaphk' user='fbeudp_mfaphk' ...
2
votes
0answers
104 views

Raster area (QGIS) problem explained

I would like to know the area that each value in a raster has... The raster I have has values from 2-15 and I would like to know the area that each value is occupaying within my polygon... Thanks! I ...
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2answers
221 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 ...
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0answers
234 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
2k 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. ...
10
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2answers
439 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
182 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 ...
15
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6answers
1k 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
165 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 ...
1
vote
2answers
218 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
53 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
131 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 ...
1
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0answers
378 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
402 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
536 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 ...
8
votes
1answer
158 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
vote
0answers
297 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
vote
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
vote
1answer
203 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
125 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
76 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
vote
1answer
157 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
votes
1answer
159 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
vote
1answer
240 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
votes
1answer
224 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
votes
0answers
109 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
244 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 ...