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

learn more… | top users | synonyms (1)

5
votes
1answer
4k views

How to configure QGIS Sextante to use SAGA?

I have been trying to set up SAGA to work using Sextante in QGIS. I have followed the instructions to configure SAGA in Sextante, with the following input in the path for the SAGA folder C:\Program ...
5
votes
3answers
2k views

Add 3rd party repositories button not in version 1.8.0 Lisboa

The available manuals and other help sources all refer to the 'Add 3rd Party Repositories button' in Plugins>Fetch Python Plugins and then the Repositories Tab. My problem is that the installation of ...
5
votes
1answer
702 views

Custom Geographic Transformation on QGIS

Is there a way to create a custom geographic transformation with specifics parameters in QGIS like in ArcGIS? Okay, I want to tranform SAD69 system into WGS84. Well, I'm in doubt because in ArcGIS ...
5
votes
0answers
826 views

Does QGIS have these CAD editing functions? [closed]

I tried QGIS for the fist time today and it seems quite capable for the task that I have in mind. However, I really miss some basic editing functionality from another GIS software that I have to use ...
5
votes
2answers
3k views

Where to store (premade) styles?

I have downloaded a set of premade styles (*.qml). Where do I have to store this files for usage?. I am using QGIS 1.7 for windows. thank you! Updates @Underdark, thanks for answering, if found ...
5
votes
1answer
857 views

QGIS inside buffer with attributes

Fairly similar to ArcGIS: inside buffer with attributes? but in QGIS. It would be convenient if the buffer layer inherited the attributes of the parent. Also I am doing inside buffers (-ve distance ...
4
votes
1answer
643 views

QGIS won't install on Mac OSX, during install says “The Installation Failed.”

I have installed the requirements: GDAL Complete 1.11 framework package Matplotlib Python module and I've made sure these requirements are properly installed by checking library/frameworks and ...
4
votes
4answers
865 views

QGIS won't read table columns in CSV import on Mac OS

I am trying to import a CSV file to QGIS, but it ends up looking like my print screen below (program is in Swedish but in the preview window you can how QGIS won't read my data correctly). I can't ...
4
votes
3answers
564 views

In QGIS is there a keyboard shortcut to open/close the layers panel?

Is there a keyboard shortcut, or even something like a toolbar button, which would make it easier and quicker to open (and close) the layers panel in QGIS (2.6). I don't see one listed under the ...
4
votes
1answer
796 views

What's the QGIS Legend Format Syntax to label percentage values?

I asked a question about formatting legend text a while back and I'm happy to see the issue has been solved in QGIS 2.6: How to remove trailing zeros from QGIS Graduated Style Class labels? But I'm ...
4
votes
1answer
683 views

How to load a WMS layer using PyQGIS?

Although there are some posts on this matter, there is no answer in anyone of them. This is why I am asking it again. One post I found was Raster layer invalid I read information from the following ...
4
votes
1answer
644 views

How to properly open an ASTER data?

Yesterday i downloaded an Aster L1B image from USGS's website. If i load it in QGIS, it doesn't get displayed properly(location wise). Even after i've enabled "On the fly" option, it's not reading the ...
4
votes
2answers
583 views

Calculating flowpaths downstream of a point

I am assessing the flood risk posed by pipeline failure. I need to calculate the likely flow-paths for flood water downstream of critical locations along the pipeline using GIS. I'm familiar with ...
4
votes
2answers
774 views

How to programmatically delete all inner rings of a polygon layer?

I have many polygon layers, each layer containing many polygons with inner rings. I know that you can delete a ring manually with QGis (Edit -> Delete ring). I need the python equivalent to ...
4
votes
6answers
2k views

Clip in QGIS 2.4.0 resulting in empty output files

I'm seeing the same problem to Clip or Intersection tool - QGIS giving empty files trying to use the Clip tool since upgrading to QGIS 2.4.0, but have not been able to fix the problem based on the ...
4
votes
1answer
203 views

Pulling CSV file directly from website into QGIS?

I want to be able to automatically update my csv files in a QGIS project. My organization has an online database that can easily export csv files. These csv files are constantly updated with new ...
4
votes
2answers
2k views

How to add Georeferenced PDF as layer to QGIS 2.0?

I have some georeferenced pdf's that I would like to open in QGIS. I have read that GDAL version 1.8 and higher will support pdf, and I have GDAL 1.10 installed with QGIS 2.0 on Windows 7, but when I ...
4
votes
2answers
4k views

How to perform SQL queries and get results from QGIS python console?

I'm writing a python script using QGIS API. I have to get results from postgres database table. The table has geometry field and other non-geometry fields. I want to perform SQL queries on ...
4
votes
2answers
962 views

Create A Maximum-Value Composite QGIS

I am looking to create a Maximum-Value Composite raster in QGIS I have three raster images: Oct 2012 Nov 2012 Dec 2012 All are in TIFF Format, Float32, EPSG:4326 - WGS 84 I want to stack these ...
4
votes
1answer
745 views

Why is tiff different in epsg 3857 and epsg 900913 in gdal

When I transform tiff from 4326 to 3857 and from 4326 to 900913 in gdal, I get different result(when display in Qgis) eventhough these two projections(3857 and 900913) should be the same. What is ...
4
votes
1answer
322 views

How to programmatically detect a canvas refresh or pan/zoom in QGIS

For my python plugin I would like to remove a VertexMarker when the user pans/zooms there map. Which is the best way to detect a canvas refresh or pan/zoom carried out by the user? Can you suggest ...
4
votes
2answers
528 views

How do I snip/split polylines at chainages?

What is the best way to snip/split lines at chainages? E.g I have a csv with the uniq ID of the polyline item and a start and end chainage. I want to extract the lines between the chainages stated. ...
4
votes
1answer
2k views

How to add CSV data with no coordinates to a polygon layer in QGIS?

I would like to add attributes from an spss database (around 300 cases) to a polygon layer in QGIS. Both datasets have a column with unique IDs. I exported the spss data to a CSV file which does not ...
4
votes
1answer
556 views

Experiencing transformation anomalies when performing a Save As to convert coordinates between NAD83-Z14 and NAD27-Z13

Good morning all: I have recently discovered QGIS and have been hoping to find a solution for converting bacthes of xy coordinates between two projection systems for our mapping system. I have known ...
4
votes
2answers
4k views

Is there a zonal statistics tool to calculate median and mode raster values for each polygon?

I'd like to calculate zonal statistics for a raster where the zones are defined by polygons in a vector layer within QGIS. Specifically I'm interested in calculating the median and mode raster values ...
4
votes
2answers
3k views

QPJ files on ESRI software

We have some GIS data, which was converted from AutoCAD dwg to TAB using mapinfo, then converted to shapefiles as that's what we are required to create. Editing the data fields was done in the shape ...
4
votes
1answer
375 views

Personal shell launcher for PyQGIS

I have changed a shell launcher found at http://inasafe.linfiniti.com/html/id/developer-docs/platform_windows.html as to fit my wish: setting the system environment variables to be able to use PyQGIS ...
4
votes
2answers
1k views

Splitting DXF layers into Shapfile layers in QGIS?

When i load a dxf into QGIS all the layers are present in the attribute table. Is it possible to split this "entities" layer in QGIS into its component parts and save each component part as an ...
4
votes
5answers
3k views

Where can I download the exercise data for The Free Quantum GIS Training Manual?

Where can I download the exercise data for The Free Quantum GIS Training Manual? The pdf of the manual just mentions the sources of the data, but doesn't give any links.
4
votes
1answer
800 views

How to use scale -rule based renderer in QGIS?

I wish to render a shapefile of builindings such that at scales below 1:5000, they have a border, and above 1:5000, they do not have a border. For this, I went into layer properties, selected ...
4
votes
2answers
1k views

Spatial query of raster data

I have population distribution data as a raster layer and exposure contours as vector (polygon) layers. What I'd like to do is use the vector layer to estimate the population indicated from the raster ...
4
votes
2answers
2k views

QGIS exporting huge SVG [duplicate]

I'm having trouble exporting an SVG(or a PDF for that matter) from the QGIS print composer. I have a relatively simple map that should, when exported as an SVG, be maybe around 1MB in size, tops. But ...
4
votes
0answers
265 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 ...
4
votes
2answers
416 views

QGIS Two Raster Data Sets with black line between the two sets where they join?

Where the two Digital Raster Quad sets (topo maps 7.5 Quad) overlap there is a significant thick black line (not a single line but wide and is wider the further south you go on the map). I am looking ...
4
votes
2answers
516 views

Is it possible to add a new line in a non-spatial table using Qgis?

While using QGIS, and having loaded a non spatial table (from a dbf or a Spatialite table), is it possible to add a new row to its table attributes? Normally in a spatial layer you have to use "add ...
4
votes
1answer
3k views

pyqgis: How to get features of selected geometries

I wonder if anybody could provide an example how to get the attributes of selected Features? I tried the folowing Code in the python Console - but I'm stuck at the point where I'd like to get the ...
4
votes
3answers
1k views

How to split features?

I would like to split a shapefile in qgis according to how the polygons overlaps. Don't know how to though? See pic for explanation:
4
votes
2answers
2k views

Problem loading vector layer (pyQGIS)

I've installed the qgis on ubuntu 12.04 following the instructions on http://hub.qgis.org/projects/quantum-gis/wiki/Download. I am trying to test the Python API and try to do the follwoing from ...
4
votes
2answers
840 views

How to represent an imaginary flat world in QGIS without using a round-world CRS

Like one or two other users, I'm interested in using QGIS to map an imaginary flat world. A previous answer suggested simply refraining from defining a CRS for such a world, but I cannot seem to make ...
4
votes
1answer
602 views

Sub-dividing a polygon into smaller polygons

In OpenStreetMap data, some large areas are tagged with a residential=yes tag. Actually within this large polygon there are multiple smaller (rectangular) houses (which are actually not drawn as yet). ...
4
votes
1answer
617 views

Generate centroids for vector polygons based on raster and land-use data using QGIS

Although QGIS has the ability to generate centroids for polygons, I am not sure how to generate centroids based on land-use development using raster data. Here's an example of what I'm trying to do: ...
4
votes
2answers
1k views

How to show two different labels of a particular vector layer with the help of QGIS?

I am working under a government project in Kolkata with QGIS. I want to show two different labels of a particular vector layer. just like we can show two different labels in Arc GIS with the help of ...
4
votes
2answers
2k views

How to create an animated map?

I am seeking to create an animated map illustrating the simultaneous movement of different objects across a large area over time. The display should be capable of playing automatically, or by ...
4
votes
1answer
1k views

In QGIS map composer, how do I get the Item Properties dialog back?

Yes, well if there is button there, one is bound to click it.... I closed both the Item Properties dialogs in Map Composer. And I can't get them to give me any joy no more... QGIS Trunk
4
votes
4answers
2k views

How to open/display and extract NetCDF files info?

I am working with NetCDF files using R & Matlab and I would like to know if the GIS community is using them. I know that ArcGIS can open & display, however most of the times the results are ...
4
votes
1answer
4k views

Saving Google Earth Location: OpenLayers Plugin in Quantum GIS

I use the OpenLayers plugin to load Google Earth Layers in Quantum GIS to digitize/identify certain features. As my work is large occassionally I have to quit Quantum GIS to resume later. The problem ...
3
votes
1answer
58 views

Layout show label and each polygon make serrated image

I want to develop "Print lay out functionality", but in output system is giving me whole image, I want to print only selected polygon. Also it is not displaying label names on print image. Please ...
3
votes
2answers
72 views

Extracting Overlapping Parts of Single Polygon Layer using QGIS?

I have a single polygon layer with over 200 buffers with a lot of overlapping areas. I want to use QGIS to create a new layer representing the overlap. I've seen several questions that are similar, ...
3
votes
0answers
61 views

spatial index intersection with qgsrectangle only computes polygones

I have the problem, that i only get polygon features inside my defined rectangle. If i switch off my polygon layer(s) i get my lines. TOC: Line-Layer on, Polygon-Layer on: i only get Polygons which ...
3
votes
2answers
528 views

How to enable UI Theme Support in QGIS 2.12?

According to the 2.12 Changelog QGIS now ships with a light and a dark UI Theme. A longer description of the UI themes can be found at Nathan Woodrows blog on QGIS UI themes. However, when I install ...