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

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4
votes
2answers
456 views

How do you create a CSVT on a Mac?

I am working with QGIS on a Mac, and understand the process for importing a CSV file. But I do not know how to create the CSVT file to define the CSV file's data types. Can someone please instruct me ...
5
votes
2answers
688 views

How to get UK postcodes for coordinates?

I m quite new with the GIS science and would like a bit of help. I m a weather forecaster and doing my MSc degree. I have a list generated with WRF and contains in a txt format the long and lats and ...
5
votes
1answer
868 views

How to reproject a raster in QGIS?

I am a history teacher and I like to make my own maps (I can never find exactly what I want). I am using QGIS 1.8 and Natural Earth data. I want to reproject their cross-blended hypso rasters into ...
5
votes
3answers
757 views

Is it possible, in QGIS, to create buffers with a set radius, but with individual values taken from the attribute table?

I am looking to create an output that consists of an 11KM buffer around a number of discrete points, where the buffer has a value defined by a column in the data sets attribute table. Is this ...
3
votes
1answer
237 views

How to buffer a point by cardinal distances to create a polygon?

I am trying to buffer a point by distances in a table to create a polygon or line for example For a point with known x,y buffer based on the following radius: North= 20m East= 21.5m South= 14m West= ...
6
votes
1answer
2k views

Sum values in a field

Using QGIS 1.8, I've got a shapefile with an integer field called AREA and I'd like to sum the values which are in this shapefile. Does anybody know how to ? Thank's a lot. Robert
2
votes
0answers
204 views

Error recognising password; importing OSM to PostGIS in QGIS

When selecting OSM Tools (Import into PostGIS) , attching my .osm file in the Input option, selecting my OSM Database, and then clicking run, I am prompted to enter a password for connection. "Enter ...
3
votes
0answers
284 views

How do I access layer attributes from within QGIS' manageR plugin?

This is probably a fairly basic question, but searches for manageR come up with a lot of noise, and there's no manageR tag. What I'd like to do is load the attributes from a particular field of a ...
0
votes
0answers
35 views

Select Move Label Tool in QGIS [duplicate]

Possible Duplicate: How to move labels in QGIS? I would like to manually move 6 labels but the Move Label Tool is unable to be selected. I have placed labels by selecting the layer and ...
3
votes
1answer
103 views

Why can't I add numeric(n,m) field values to PostGIS geometries in QGIS 1.7.1? [closed]

Actually I'm using QGIS 1.7.1 to create and visualise some geodata hosted by PostgreSQL 8.4 and PostGIS 1.4.0. The geodatatable is defined like this: CREATE TABLE u2_baum ( baum_id integer NOT ...
1
vote
0answers
161 views

Qgis 1.9 on Ubuntu 12.04 constant crashes as soon as I try to do anything

I can get a google earth physical layer open but as soon as I try to open a vector file it crashes-just goes away-no error message, nothing
1
vote
0answers
520 views

QGis CadTools CAD Console

I need help with the Qgis CadTools CAD Console commands. According to these help files there are six commands. I just can't get them to work. Can someone help me? Thanks
3
votes
1answer
245 views

QGIS 1.8 does not launch

QGIS 1.8.0-1 does not launch (nor its companions: Browser, Grass, etc.) neither on machine with Win XP SP3 nor with Win 7 (GRASS installed separately works well). Console displays a message on launch: ...
1
vote
0answers
91 views

How to get the geometry of a polyline to a specific precision?

In python, I use point = geom.asPolyline() but it looks like I am not getting any precision just whole numbers? How can I get the geometry and a certain precision?
5
votes
1answer
1k views

Remove duplicate nodes in QGIS

I am trying to create a polygon feature from an enclosed line feature using the Geometry Tool: Lines to Polygons. When I do this, I get several spikes with the newly created polygon. I then run the ...
3
votes
1answer
183 views

How to use the QgsDiagramRendererV2?

I'm writing a plugin for QGIS in python in the QGIS API doc, I can see the QgsDiagramRendererV2 class, under the qgs.core section http://www.qgis.org/api/classQgsDiagramRendererV2.html What I'm ...
5
votes
3answers
869 views

Convert Ordnance Survey NTF data to QGIS compatible format

Is there a way of converting Ordnance Survey NTF data to QGIS that will correctly import the data and build polygons? QGIS will read the data as is, but it imports the polygons only as ...
2
votes
0answers
34 views

How can I set python path and version for QGIS? [duplicate]

Possible Duplicate: Couldn’t load SIP Module When I'm starting QGIS I'm getting the problem: "Couldn't load SIP module. Python support will be disabled." And there is also: Python version: ...
8
votes
1answer
474 views

How to split two interscting polygons by the average linestring of the shared area (QGIS / python shapely)

I have two polygons, POLYGON((-5 -5,-5 5,5 5,5 -5,-5 -5)) POLYGON((1 1, 1 7, 7 7, 7 1, 1 1)) and wish to split them evenly. The result should be a split along the red marked line. I'm using ...
2
votes
0answers
276 views

Postgresql Query Plugins Not Returning Results in QGIS

I'm using the Fishnet function as described here to create a grid. If I use the following SQL to call the function to position a grid where I want it (I'm using NZGD2000 SRID = 2193) the query ...
1
vote
1answer
148 views

Taking a 'custom' map and transforming its x/y co-ordinates to 'real' long/lat co-ordinates?

I was wondering if someone could help me out with a little project I'm working on. I'll try to describe what I'm trying to achieve - if it doesn't make sense, please let me know. I have in front of ...
2
votes
1answer
3k views

How to setup QGIS Web Client?

So we've installed QGIS Server and things look to be working well (thanks Underdark for the great tutorial). Next up we want to get the QGIS Web Client working. It appears we're missing a step or ...
4
votes
0answers
260 views

How to symbolize vector features using RGB values stored in three fields? [duplicate]

I need to symbolize a vector layer in Arcmap based on RGB (or HSB - can do either) values found in fields in the attribute table. I'm working with up to 10 different datasets, each with over 100 ...
3
votes
1answer
1k views

How to use field calculator from QGIS Sextante plugin

I am trying to use the Sextante field calculator to calculate a field for a buffer radius using a categorical text field. The formula works fine when I run it using the standard QGIS field calculator ...
2
votes
0answers
43 views

How to set different label content for different scales? [duplicate]

Possible Duplicate: How to accomplish conditional labeling based on map scale and attribute in QGIS 1.7 I'd like to show different label content at different map scales. Zoomed in, I use ...
5
votes
2answers
601 views

How to accomplish conditional labeling based on map scale and attribute in QGIS 1.7

How can I label with qgis 1.7, based on attribute and scale of map? For example scale>1:1000 then label all those features whose area>100000 at font size 12 and those features whose area<99999 at ...
16
votes
1answer
186 views

Can we create views over a raster table in Postgis2.0?

Is it possible to create PostgreSQL views over a table that contains raster data? I have succeeded in creating the view but the entry in raster_columns is not correct (all the raster info is ...
5
votes
0answers
346 views

Can Quantum GIS replace Proprietary GIS? [closed]

I’m an MSc GIS student in the final year of my studies. I’m researching for my dissertation project which is entitled ‘Can Quantum GIS replace Proprietary GIS in large organisations?’ I’m primarily ...
5
votes
2answers
1k views

How to show a message box in QGIS?

I am starting to develop a plugin for Qgis using python, which i am very new at, and would like to view some results of variables by displaying a message in QGIS. How can I do this?
3
votes
1answer
621 views

Qgis problem clipping a raster .asc file, the output is unreadable

I am currently using QGIS (1.8.0) to prepare files for use in MaxEnt to predict species distribution in a new territory in Argentina. I need to a) cut the raster files (bioclim, and others) to a ...
9
votes
3answers
976 views

What are common methods for converting raster digital elevation data to vector contours?

In researching this I have found many references to the opposite, creating elevation data from contours, but nothing regarding contour creation. Preferably, I am looking for open source solutions like ...
8
votes
1answer
365 views

How to see what lines have changed in an updated Shapefile?

I'm using my county's GIS data to update the roads in OpenStreetMap. I have a copy they published last year and one that was just published, and I'd like to find all the LineStrings that have either ...
2
votes
1answer
1k views

How to change 2 rasters to have the same dimension?

I am new in Quantum Gis 1.8 and have the following problem. I have extracted two raster files(land_cover.asc and soil.asc) using a polygon of my study area (area.shp) Apparently the raster dimensions ...
2
votes
0answers
109 views

How to install QGIS on Linux NAS using IPKG

I have a Linux -Based NAS that I want to install QGIS onto. Since I am administering through a web interface from a Windows based PC, how can I install qgis? Is there a way maybe through IPKG? Or any ...
6
votes
3answers
1k views

How to split lines on vertex?

I've searched a lot but didn't find an answer: When editing lines with QGIS, I often need to split a linestring exactly on one of his existing internal vertices, but I can't find a way; I've tried the ...
5
votes
2answers
1k views

Shape-file encoding problem in QGIS 1.9.0 (built with GDAL 1.9.2)

I have googled a lot but failed to find the answer. My configuration is: Ubuntu 11.10 Quantum GIS - 1.9.0-Master 'Master' (caae7b7) GDAL 1.9.2, released 2012/10/08 Shape-files refuse to open in ...
2
votes
1answer
146 views

How to hide all fields at once in QGIS 1.7

Is there a way to hide all the fields at once in QGIS 1.7? I see where I can hide one field at a time but I would like a button which does it all at once.
7
votes
2answers
320 views

How to run a spatial query with a raster and vector layer in QGIS?

I have a soil map (vector-polygon layer) and a map of the crops farmed in the same area (raster layer, from the US Cropland Data Layer). I would like to calculate for a given soil type, the surface ...
3
votes
1answer
94 views

How to display the label with “Identify Features” in QGis?

I have been struggling for one hour with this simple problem : I have a raster layer. I would like to display the label and not only the band value when I use the "Identify Features" button. Is it ...
3
votes
1answer
2k views

How to export shp to kml?

I already browsed your FAQs, and could not come up with a good answer, I am trying to export shp files to kml to be placed on Google Earth. On a previous version of QGIS it was as simple as right ...
3
votes
1answer
171 views

How to get raster layer pixels contained in a shape defined in a vector layer

I am new in QGis python plugins dev and I have a "maybe stupid" question (in the title :-) ). I try to retrieve pixels (from a raster layer) which are "contained" in a polygon defined in a vector ...
7
votes
1answer
13k views

How to crop Shapefiles in QGIS?

I need to clip a large and very detailed .shp file in QGIS showing environmental data similar to a temperature map. Is there something like the very simple crop tool alike in photoshop where you can ...
4
votes
1answer
489 views

Why are the polygons in my GML not rendered?

I tried to view GML files from download services ( http://services.cuzk.cz/gml/inspire/cp/epsg-5514/ ) and I have a problem with viewing of polygons from layer "CP:CadastralParcel". This Layer ...
5
votes
3answers
166 views

How to make same installation on multiple machines?

What is the easy way to make the "same" Qgis installation (same menu, same plugins, same prefs...) on multi-PCs, 10 or 12 laptops ? thanks for your help.
9
votes
4answers
5k views

Tutorial on how to model flooding using data from gauging stations along rivers in QGIS?

Can someone please direct me to a tutorial where I can learn more about how to model flooding using data from gauging stations along rivers using QGIS?
2
votes
1answer
257 views

Visualizing KMZ network link in QGIS

Is it possible to open and visualize and kmz network link in QGIS. If so what are the setps involved? Thanks in advance Cheers
11
votes
2answers
1k views

polishing qgis map for publication using inkscape

I have a problem modifying the map I created in QGIS. I need to add some text on the map and axis labels. Apparently, labels cannot be rotated in qgis, so this I need to do in inkscape or in a related ...
4
votes
1answer
725 views

Can I disable mouse wheel zoom in QGIS?

I am having problems with the zoom in QGIS 1.8.0 where a slight move of the scroll wheel on the mouse zooms way way out. It will re-render at each zoom level and with large datasets it takes over the ...
3
votes
0answers
230 views

How to debug Quantum GIS PlugIn Visual Studio DLL?

I develop a Quantum GIS plugin layer using Microsoft Visual studio and placed it in my plugins folder of my customized quantum gis application. I now intend to debug the DLL using Microsoft Studio. ...
8
votes
3answers
1k views

How to fix “Unable to initialize ODBC connection to DSN for ALC_AV_CO”?

So I am new to the QGIS community, and I have been trying to bring in some rather large access databases with little to no success. I have windows 7, so I've gone in through administrative tools/Data ...