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

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6
votes
1answer
594 views

How to connect places (points) without crossing lines?

I have two sets of data. One with placemarks represented by blue dots in image below, and another set of geographic data with lines represented by grey lines. 1) For the first point in drawing, I'm ...
1
vote
1answer
396 views

How to add a progress bar to a python plugin?

I would like to add some type of progress bar to my Qgis python plugin. Can someone point me to an example?
3
votes
1answer
87 views

Is there a way to scale to 1:1 in QGIS Cloud?

Someone knows if with QGIS cloud Pro Plan, it's possible have a scale till 1:1. I use QGIS to draw small stuff on my gis (archaeological finds, as really small pottery's sherds) and I need a scale ...
15
votes
6answers
4k views

What's the best way to produce a density map from weighted points in QGIS?

I'd really like to repeat the functionality of the ArcGIS Kernel Density tool - how could I do that? I would like to limit answers to easy-to-install free-and-open-source software – i.e. QGIS ...
4
votes
1answer
323 views

How to use the OGR/GDAL configure options in QGIS python environment

I’m looking for a solution how to use the OGR/GDAL configure options (--config) in the qgis python environment. http://trac.osgeo.org/gdal/wiki/ConfigOptions Setting special configure options is ...
2
votes
0answers
56 views

Is there a way to distinguish between digitized and pasted features?

Is there a way to tell if an added feature in QGIS is in fact a newly digitized one or a pasted feature? I think QGIS is treating both cases in the same way, emitting the same signal: ...
3
votes
2answers
177 views

How can I create a portable script for coordinate conversions to run from USB?

I would like to be able to convert Lat long values in wgs84 to the swedish RT90, the values are in CSV files under headings X and Y. I would like to have this portable, an eg runned in a script in ...
1
vote
1answer
111 views

Projection Transformations [duplicate]

Possible Duplicate: How can I measure area from geographic coordinates? I created my spatial tables in WGS-84 with SRID:4326, I want to transform them to UTM Projection to measure length ...
5
votes
1answer
639 views

Can QGIS handle .adf attribute data?

I have been using QGIS for about 4 months now and its been great to learn a new package. I have been trying to open a source raster (*.adf) files in QGIS. I can display the raster set itself, ...
5
votes
1answer
484 views

Error Installing libgdal1 Package

I'm trying to install the libgdal1 package on Ubuntu 12.04, but the apt is returing this error: dpkg: error processing /var/cache/apt/archives/libgdal1_1.9.1-2~precise4_amd64.deb (--unpack): ...
4
votes
1answer
1k views

How can I duplicate a layer in QGIS?

I'd like to display the same vector data in different ways as different layers. While it's very handy to be able to copy and paste the layer style in 1.8+, it would be nice to be able to select a ...
5
votes
3answers
3k views

New QGIS install can't find GISBASE

At QGIS startup I get the message: "QGIS couldn't find your GRASS installation. Would you like to specify path (GISBASE) to your GRASS installation?" (Windows 7) No amount of rooting around the ...
8
votes
1answer
2k views

How to reproject a raster file in QGIS with datum transformation?

I want to reproject a tiff raster file from projection A (ETRS89/UTM Zone 32) to projection B (DHDN/Gauss-Kruger zone 2). The two projections have a different datum so I have to use a datum ...
4
votes
2answers
186 views

What is the fastest way to iterate through a list of features?

I have written a QGIS plugin and it iterates through all features in a layer using provider.select() and compares geometry. The problem, the plugin is very slow. If there are 114 features in a ...
7
votes
0answers
67 views

How can I automatically split a spatial layer to a grid [duplicate]

Possible Duplicate: Divide vector in equal smaller parts in QGIS or similar I am a software engineer and the company I work for has a project that needs some spatial data manipulation in ...
6
votes
2answers
341 views

Why is this spatialite polygon layer not displayed properly?

In QGIS, I have a spatialite multipolygon layer that have full objects in attribute table but do not display random ones as I scroll and pan around: Vietnam map at zoom level 1:16000000 - some ...
5
votes
1answer
94 views

Is it possible show the feature attributes dialog when I add a feature in code?

I want to know if it is possible to make the feature attributes dialog in Qgis show up when I add a feature by code using: QgsVectorLayer::addFeature( tFeature ) This is available when I add ...
2
votes
1answer
363 views

Flattening JP2 files to single band (i.e. averaging bands)?

I have created thousands of png tiles using ArcGIS and have merged groups of them into large jp2 files for serving via GeoServer. I need to flatten these to a single band so that I can apply a colour ...
5
votes
2answers
5k views

How to connect to Postgres with QGIS?

Oddly, it should be simple, but I can't connect to a local PostGIS database. My installation is with Mac OS X (10.8), Postgres.app (in doc it's said to have PostGIS included) and Quantum GIS 1.8. ...
4
votes
1answer
196 views

How can I fix DLL loadfailed with Polygonize in QGIS 1.8? [duplicate]

Possible Duplicate: Qgis polygonize problem - DLL load fail I'm getting the following error message when I try to use the polygonize tool in QGIS 1.8 (windows 7): Traceback (most recent ...
2
votes
1answer
70 views

Is there a version of merge in QGIS that works like “Difference”?

I can't seem to find a tool to merge files from the active TOC into one file... The datamanagement --> Merge Shape files only allows you to choose a directory of shapefiles to merge which is really ...
1
vote
2answers
2k views

What do I need to change to get scale bar units other than degrees?

Measurements done in QGIS on my project are done properly using whatever unit is set in: Settings > Options > Map Tools > Preferred measurements units but the scale bar decoration and scale bar in ...
1
vote
1answer
91 views

Need to generate ids to connect points and polygons

I have a simple question as I am just getting my head into GIS. I am trying to compare the demographics of charter schools to traditional public schools. I have universe listings (lat,long) of US ...
1
vote
0answers
28 views

Access to Attribute join via command

I have 1.8 Quantum GIS, the menu "attribute join from the FTOOLS" no appears in the screen , is there a way to access via command?. thanks in advance
4
votes
1answer
1k views

GEOS and Shapely installation on Windows

When trying to install Shapely on my Windows 64bit computer, I cannot get the GEOS library to work. So far, I have run the OSGeo4W installer from which I installed GDAL (I believe the geos library ...
4
votes
4answers
786 views

TIN interpolation crash in Qgis

I have problems using the function TIN(linear) interpolation in Qgis. The program crashes when larger areas is interpolated. Map properties: vector map, Geometry typ = Point, features in this ...
4
votes
1answer
357 views

Disable sounds/beeps in QGIS?

Is there any way to disable, mute, or otherwise change the incessant message 'beep' in QGIS? I need volume on the PC for other unrelated notiifications yet am tired of apologising for the echoing ...
6
votes
2answers
719 views

How to get correct area calculation using Google Mercator?

i use QGIS with openlayers-plugin and i´ve loaded google satellite as a layer. what i want to do is making a shape-layer (polygon) with the goal to get the area values of the polygons. i´ve activated ...
5
votes
2answers
3k views

Calculate area of intersecting polygons in QGIS

I have two collections of shapefiles: 1 - postal codes, administrative and political areas 2 - various land use categories like parks & allotments, and points like trees I want to produce ...
10
votes
1answer
489 views

How to render a table with mixed geometry types in QGIS?

I created a table with geometry type "GEOMETRY" AND inserted data of point, line and polygon type. My question is how to show this spatial data Qgis not supporting for geometry type "GEOMETRY".
7
votes
1answer
593 views

How to reopen hidden panels in print composer?

I unfortunately deleted the menu (Qgis 1.8.0) in print composer (settings for labels etc) . Now I am wondering how to display it again? The menu is gone in all my projects and I could not find a ...
3
votes
1answer
305 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
610 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
672 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
662 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
209 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
1k 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
193 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
260 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
31 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
97 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
468 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
244 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
83 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
902 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
168 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
772 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
33 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
447 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 ...