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

learn more… | top users | synonyms (1)

0
votes
2answers
50 views

What Open Source Packages are available to provide routing

I am looking for ways to validate mileage charged by our contractors. They are paid from a central location to a customer, and then from the customer to a drop off location. I use QGIS for a bunch ...
2
votes
0answers
10 views

Best tool for interactively determining upslope and downslope areas on a DEM

I know SAGA GIS can be used to interactively generate maps of upslope and downslope areas for a cell within a DEM, but the output is pretty ugly. An upslope area is defined as all cells (for a ...
1
vote
1answer
212 views

clip one layer with the current map layers

I work in a little companie where the main goal of employees in GIS is to have a quick view of the issues on a study area. It would be very useful to have a tool wich clip all the layers of the ...
2
votes
0answers
56 views

How to design labels which look like a fraction (with a fraction line)?

I want to create labels like a fraction using data from two columns. I have tried to use: "Field" || '\n' || '――' || '\n' || "Field2" but it doesn't look good. How can I do it using other method? ...
2
votes
0answers
27 views

Is there an issue with Zonal Statistics calculating wrong mean values?

I tried to solve the following issue by myself but without success. On the one hand I have a raster file which is the result of the processing "shapes to grid" tool. On the other hand I have a ...
2
votes
1answer
35 views

What's wrong with my expression to control label colors?

I am struggling to alter the label colours according to field values (as strings) in the attributes table. In my mind what I want is: If the string in column X = 'Proposed' Then label the point ...
1
vote
0answers
28 views

Why does my clipped raster seem to be slightly moved?

I'm having some problems with clipping rasters. I started clipping my raster using extents, but I saw that the clipped raster is different from the original raster. I created a virtual raster to use ...
1
vote
1answer
22 views

How to use inbuilt tools in QGIS Modeler?

Is it possible to incorporate inbuilt tools like, for eg: vector grid of Research tools in QGIS model builder ?
0
votes
0answers
12 views

How to save a WMS layer at multiple resolutions as .tif using pyqgis

How can I export a wms-map-extent as a .tif from QGIS? Is it possible to call the "Save as.." function of a WMS-raster-layer from pyqgis? (E.g. by simulating right-clicking the layer, choosing "Save ...
1
vote
1answer
84 views

What's the purpose of wms_metadata.xml and admin.sld?

I've installed QGIS Server and it works fine. But in /usr/lib/cgi-bin/ folder I've found 2 additional files - wms_metadata.xml and admin.sld. What is the purpose of these file? I've never used them.
9
votes
1answer
3k views

How to display geoJSON from an URL in a layer?

I am looking for some type of plugin or code which would allow me to add a geojson URL, define the areas to input the lat/long variables from the visible Qgis canvas map and call/render the results ...
-3
votes
0answers
16 views

Script Not working only Blank result is created [on hold]

from qgis.core import * from qgis.utils import * from qgis.gui import * from PyQt4.QtCore import * from PyQt4.QtGui import * QgsApplication.initQgis() mapinstance = QgsMapLayerRegistry.instance() ...
2
votes
1answer
228 views

Showing unknown SRS (native SRS) when importing shapefile into GeoServer

I am facing a problem on an unknown SRS when I am importing a shapefile into GeoServer. I am trying to import a shapefile into GeoServer but when I am publishing the shapefile, it is giving the ...
1
vote
1answer
17 views

QGIS show gdal_polygonized file in EPSG:54004 instead of EPSG:3857

I am polygonizing a TIFF with the gdal_polygonize.py and the resulting Shape is shown in QGIS in the wrong projection - EPSG:54004 instead of EPSG:3857. I have a TIFF in EPSG:3857 and polygonize it ...
0
votes
1answer
46 views

Cannot load postgis layer from sql string in pyqgis

I'm trying to load a layer using the following code in qgis python console: sql = "(select the_geom, ID from mytable)" uri = QgsDataSourceURI() ...
2
votes
1answer
19 views

Calculating distances from points to the centre of cells

I am using QGIS 1.8.0 (using older version because I need the Qmarxan plugin which is not available for 2.4.0). I have a study area that has a vector laying of "planning units", or cells over the top ...
2
votes
0answers
21 views

How to develop a real-time navigation App using QGIS API?

I want to develop a navigation application based on QGIS using C++, for live tracking. I think it is quite normal for GIS to do such things, especially QGIS as it is a very mature GIS platform. But ...
1
vote
2answers
32 views

How can you create a depth raster from a DTM and a polygon in QGIS?

I have a DTM raster and a flood outline in polygon format - how do I create a depth raster for the flood outline (i.e. flood level minus DTM level)?
1
vote
1answer
291 views

How to export a geojson file with correct order of coordinates?

I was testing rendering of data via GitHub in geojson format, because I wanted to use it for INSPIRE data. INSPIRE data are in GML 3.2.1 format. I've downloaded one of datasets from ...
3
votes
1answer
134 views

Is it possible to label bar charts?

I have added bar charts to my map and this works fine. But I have no idea how to add values to the bar chart. For example one bar shows the value of 2000 and another shows the value of 2100. Is it ...
2
votes
1answer
28 views

In QGIS, is it possible to save graduated styles to use on different columns?

I'm using QGIS to produce thematic maps of 9 quantities (given in 9 columns in the attribute table) which have values broadly within the same range and I would like to plot them using the same ...
3
votes
1answer
29 views

Using QGIS to create a table of correspondence between two area layers

I have two area layers over a map of Australia, and I want to know if it's possible to use QGIS to create a table of correspondences between them. The Australian Bureau of Statistics provides ...
0
votes
0answers
17 views

How to reference a number variable in r.mapcalc within QGIS graphical modeler

I need to run the following formula in r.mapcalc: (xor(abs(A-B),abs(A-C))>120)*A I would like to however use a user defined number input variable instead of the 120. I already have this variable ...
1
vote
2answers
27 views

kml does not overlay correctly in QGIS

In QGIS, when I insert a kml contour that was created in Google Earth, it appears misaligned in respect to all the other layers. Note in this image how the red contour is moved upwards with respect ...
1
vote
1answer
97 views

Analyse slope gradient from LiDAR .asc data

I'm new to using QGIS. I have purchased some LiDAR data which downloads as .asc format, is there a way to analyse the terrain slope angle from this data or does it need to be converted into DEM? ...
10
votes
4answers
4k views

How to create equidistant points in QGIS?

I am trying to create points (new layer) at specific distance along the road (existing layer) in QGIS. This gives solution for ArcGIS. How to achieve this in QGIS? This one explains how to create ...
0
votes
0answers
19 views

insert row into postgis query table in QGIS

I find I am using QGIS (2.4) more and more as a client for PostGIS database tables with geometry, but also for tables without geometry, partly because it's good just to use the one application and ...
1
vote
0answers
15 views

How to create a svg item onto Map Canvas in QGIS API?

I'm working on a project with QGIS-2.4.0 API using C++. I need to load some svg files to the application for displaying as symbols. QGIS API has a class named QgsMapCanvasItem, which is an abstract ...
1
vote
0answers
25 views

Creating Form in QGIS

I want to create a form for editing attributes in QGIS. I have a lot of question and hope somebody can suggest how they work or where I can read about the next elements of form: Classification List ...
0
votes
0answers
16 views

Is there an editing function in qgis cloud? [on hold]

does someone know if an editing function exists in qgis cloud? or maybe is planned?
1
vote
1answer
32 views

Reprojected Shapefile does not align with Openlayers Plugin

I am based in NSW, Australia. I have a shapefile that when I underlay with the openlayer plugin (google satellite), the shapefile is skewed despite all my efforts to correct it. I changed the ...
1
vote
0answers
39 views

Dark Object Subtraction QGIS

I'm trying to do Dark Object Subtraction (DOS) for a Spot2 and 4. I have calculated the TOA reflectance and now want to get the at surface reflectance. Using QGIS I would like to know how I can do ...
2
votes
1answer
28 views

How to store a password during one QGIS work session?

I'd like to get into qgis-plugin development, but am rather new to both python and QGIS development. I intend to write a plugin which connects data from a mysql database to shapefiles. As the data is ...
3
votes
2answers
35 views

QGIS doesn't create the correct projections when creating new shp files

I received shapefiles exported from ArcGIS with EPSG:2227 as the CRS, which should be: +proj=lcc +lat_1=38.43333333333333 +lat_2=37.06666666666667 +lat_0=36.5 +lon_0=-120.5 +x_0=2000000.0001016 ...
1
vote
0answers
14 views

Can HTML annotations be autogenerated for each location in QGIS 2.4

Can HTML Annotation Boxes be autogenerated on the whole map, linked to locations, and always have the same html file loaded for all of them?
4
votes
0answers
250 views

How do I install Orfeo toolbox and Qgis 1.9?

I'm having a lot of trouble getting Orfeo toolbox and Qgis 2.0 working. I followed the qgis wiki instructios, added the ppa, installed qgis 1.9 (it's beautiful, great work!). But when i tried to ...
0
votes
1answer
119 views

Problem executing Mean Shift Segmentation

I have a problem executing the Mean Shift Segmentation in QGIS with Orfeo Toolbox. I put all the parameter to execute and then, nearly 5s after appear the message that SEXTANTE could not open the ...
0
votes
2answers
56 views

How to style graduated using size-scale field

Is it possible to style based on size-scale field using graduated symbol but instead of using color ramp, I would like to display its size. I would also like to display this in the legend in the map ...
2
votes
2answers
58 views

Deleting unconnected lines with QGIS

I am using a road map in shapefile format in order to calculate a route between two points. The map is downloaded from OpenStreetMap and it has small unconnected lines that are messing up my routing. ...
10
votes
4answers
9k views

Changing CSV layer attribute value from text to number in QGIS?

I read in a CSV file for linking to a .shp file. All the variables that are just numbers came in as text. How do I change the text variables to numeric in QGIS?
1
vote
1answer
48 views

Setting up QGIS Server at low cost for small user community?

I want to setup QGIS Server at a low cost for a small user community (mainly me). Parameters: Some data is private so something like qgis cloud not an option (not enough money for paid option). ...
1
vote
1answer
43 views

How to use bold text in QGIS font marker symbol?

Is it possible to use bold text with the Font marker symbol in a QGIS (point) layer?
1
vote
0answers
54 views

Cannot Save Edits to File Geodatabase Replica in QGIS 2.2

When trying to edit a File Geodatabase Replica in QGIS 2.2, everything works as expected until the user saves their edits. When pressing save, all edits revert back to their original state with no ...
4
votes
1answer
186 views

How to include streaming media into an OpenGeo system to monitor live-tracked animals?

I am wondering how to include streaming media (video), or camera feeds, into an OpenGeo system to monitor live-tracked animals. I am currently doing so with different applications, but I want to do ...
4
votes
1answer
115 views

Calculating a Unique ID on a Subgroup of Polygons

I would like to assign a unique ID to polygons in a dataset. The catch to my issue is that I would like polygons that fall within a polygon to have the same unique ID. My example is related to ...
0
votes
1answer
125 views

Merging Raster: ImportError: No module named _gdal_array

When I try to merge rasters I got following error message: _gdal_array = swig_import_helper() File "C:\PROGRA~1\QGISDU~1\apps\Python27\lib\site-packages\osgeo\gdal_array.py", line 18, in ...
2
votes
1answer
33 views

QGIS Intersection problem

The QGIS Intersection tool is not working for two shapefiles in Version 2.2 or 2.4 (haven't tried earlier versions). I get a new shapefile with all the attributes, but no features. However, when I use ...
1
vote
0answers
27 views

Is there a way to automate POI collection from websites?

I am searching for an easy method to get lots of points geotagged/georeferenzed into several shape files. I am working at a project where I need to collect all parcel shops in germany (but I will try ...
1
vote
1answer
33 views

What's the reason for this Invalid Layer “Cannot open GDAL dataset …” error

When adding a rasterfile with QGIS python console there appears an error when the first letter of a rasterfile to be added is not written in capital letters. Why this behaviour? Example case1: ...
0
votes
2answers
855 views

How to fix ImportError: cannot import name MAXREPEAT on Ubuntu 12.04

I have problem with installing qgis 2.0 on ubuntu 12.04. If I don't install qgis-python plugin then qgis starts normally but I can't access python console in plugins. If I install that plugin then I ...