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

learn more… | top users | synonyms (1)

-2
votes
1answer
31 views

Identifying projection for shapefile with unknown coordinate system, no z values and no measures?

I am attempting to create a GIS Project with multiple Brazilian cities. I have been collecting, and am interested in, shapefiles that delineate the neighborhood boundaries of said cities. One city's ...
0
votes
0answers
13 views

Comparing geographical coordinates of two GML files in a .bat file

I am transforming large files from a projection(pr1) to ETRS89 and back to the projection(pr2). In order to see if the transformation is consequent I am trying to compare the coordinates of pr1 before ...
2
votes
1answer
34 views

QGIS : How to cover a number of points with disks?

I have to cover some points with disks. These disks are not of a fixed size, they have to constraints: - a maximum diameter, and - a maximum number of points covered. I would like to ...
0
votes
2answers
29 views

How to create spline in QGIS

I want to create spline in QGIS. I have tried to use Cad-tools - Create spline line\poligon but I can only draw it and can't save. What is wrong I am doing? Is there other way to create spline?
0
votes
0answers
4 views

Tiled raster image to be placed in an OSM/ Leaflet.js map

I have a mapoverlay in a custom projection which I need to add as a layer to an open street map map within a website. Since I was not able to change the projection earlier, I decided to manipulate the ...
1
vote
1answer
26 views

How to scale with radius attribute

new user of QGIS. I would like to style vector data based on an attribute (radius). The actual unit is in nautical miles. I don't want to use size-scale field or buffer to style the point rather I ...
1
vote
1answer
57 views

Why is feature.geometry() None in my user-defined expression function?

I'm trying the user-defined expression functions for QGIS, as listed on Nathans blog: http://nathanw.net/2012/11/10/user-defined-expression-functions-for-qgis/ I always get the feature.geometry() as ...
1
vote
0answers
33 views

My map is little bit off

I am pretty new in GIS things and i have been learning how to use QGIS. Most of the maps are fine, but yesterday I went to GIS center at my University and I got the maps of my country that I will be ...
0
votes
0answers
12 views

Holes in Rasterized DEM from QGIS [duplicate]

I converted vector contours to a raster DEM using the rasterize command in QGIS. Generally the DEM looks correct, but the are a large number of holes in the DEM. The holes have a value of zero when ...
3
votes
2answers
42 views

How to set Zero values to NULL using QGIS pycalc?

I'm using QGIS 2.4 pyclac and windows 7 OS. I have columns that should show NULL value but instead of that they show Zero (0) value, I need those fields to be NULL. This far I have seen a script that ...
1
vote
0answers
30 views

Scaling features based on an attribute

I would like to scale polygon features by a specific factor I have calculated for each feature in a feature class. I know of the Scale tool, however it only allows for manual entry of a scale factor ...
0
votes
0answers
27 views

How to set image size with Image Map Plugin on QGIS 2.4?

I use QGIS 2.4, but I have noticed that the "Set Map/Image Size" feature on the HTML Image Map Plugin no longer seems to work. No matter what you set the "Set Map/Image Size" for, your image will ...
2
votes
0answers
35 views

3D visualization of terrain data and orthophoto using GRASS NVIZ via QGIS

How can I make 3D visualization of terrain data and orthophoto using GRASS NVIZ via QGIS? I am quite new with GRASS. I have only managed to get a 3D view of the terrain so far.
0
votes
0answers
14 views

How to access the map in QGIS Web Client WEB interface

Once you have done all the instructions in this link below, I can access the WMS in QGIS smoothly http://anitagraser.com/2012/04/06/qgis-server-on-windows7-step-by-step/ Now how do I get access to ...
1
vote
1answer
24 views

gdaltools in qgis v2.4?

Where's the GDALTools plugin for QGIS 2.4? It's not listed in list of available plugins, and it's seemingly not installed out of the box. Is it just that it's not yet compatible?
1
vote
0answers
13 views

How to install the QGIS Raster Lang plugin?

I´m trying to install the rasterlang plugin for QGIS. I tried several things on this website but it seems to be quite complicated because I need to install binary files and other files. The idea ...
0
votes
0answers
11 views

QGIS plugins - how to use a custom behaviour on right click and actionPan on left click?

I have been struggling with this problem for quite a long time. Here we go : I implemented a maptool that draws a red cross on the point that is being right-clicked on. There are good how-tos, such ...
1
vote
1answer
17 views

Performing transformation from GHANA GRID to WGS 84 using QGIS?

I have a shapefile which was referenced using Ghana's grid system. I imported it to QGIS and specified WGS 84 but the coordinate bar still displays the Ghana grid values in the coordinate bar. Is ...
2
votes
1answer
18 views

QGIS Processing - Additional Creation Parameter for GdalWarp

I am having a hard time getting the "Additional Creation Parameters" to work when using GdalWarp through the processing toolbox. I am trying to set the nodata value to 0 for the output raster. ...
3
votes
2answers
67 views

Unable to zoom beyond scale of 1:2,256 in QGIS?

In QGIS, whatever might be the source, I couldn't zoom beyond the scale of 1:2256. Whether it's a raster or vector, result is the same. Does anyone know how to fix this ? Edit: Thanks to Chris. ...
2
votes
1answer
31 views

Rasterizing Contours - How to remove 0 values

I want to convert vector contours to a DEM. From other posts, I wanted to utilise the Grass r.surf.contours tool. Initially I converted the vector contour layer to a rasterized contours using the ...
2
votes
2answers
47 views

Date-format conversion

I'm using Time Manager and QGIS 1.8.0 and I am stuck at date-format conversion. Time Manager needs Gregorian format YYYY-MM-DD HH:MM:SS.ssssss in text field and I have thousands of records in ...
3
votes
1answer
33 views

How to install Apache Web Server from OSGeo4W?

Good morning, I'm trying to create a QGIS web client on my Windows 8 But with OSGEO4W not appear the option to make Apache installs Web Server, as of this writing in several tutorials and ...
3
votes
1answer
34 views

Why is the OSM map itself is not visible in my qgis window?

I'm new in working with QGIS. I have tried to download an OSM map of Rome and its surroundings into my QGIS. As far as I am concerned, I have followed each step which I could find on various ...
3
votes
1answer
126 views

Using Engineering symbols (*.svg) in QGIS?

QGIS looks straight forward except for the symbols or icons. I have created SVG symbols and when I place my pointer to the obvious blank areas in the symbol library a pop-up says that my symbol is ...
1
vote
0answers
33 views

Where can I find “QGIS Training Manual” data? [duplicate]

I can't find data for this lesson in Quantum GIS: 9.4 Lesson: Supplementary Exercise. Can anybody help me?
0
votes
1answer
19 views

Gdal_sieve not working?

I'm using the Sieve command within QGIS (Raster > Analysis > Sieve), but when I run the command with any variation of parameters, it completely changes the histogram of my raster data from between ...
2
votes
1answer
38 views

Best Landsat band for forest classification?

Using Qgis and the Semi-Automatic Plugin for Classification, which are the best Landsat bands to use to classify trees species (in central Argentina)? In Landsat 5, 7 and 8?
2
votes
0answers
37 views

Setting up qgis web client

I have a problem with setting up a qgis web client on remote server. I set it up on localhost and it runs smoothly, but when I done exactly the same on remote server it is just not working, even a ...
2
votes
1answer
36 views

PyQGIS - Start/Stop Editing with data Provider - Commiting changes

I want to edit a specific field for a QgsVectorLayer, within a QGIS application. I am facing inconsistent results from my code, ie: changes are not alway commited. Please could someone point me to ...
4
votes
1answer
66 views

How do you set the position of a plugin window when you start the plugin?

I'd like to set the position of a plugin's window or dialog relative to the map canvas frame. For example, if I start a plugin, I want it to appear somewhere in the left upper corner of the map ...
3
votes
0answers
52 views

How to calculate percentages using QGIS field calculator expression?

I am new to QGIS. I am wanting to calculate a field using other fields and some operators. Here is my expression: case When "RVM_CAT" = 'B' OR "RVM_CAT" = 'C' Then ("PC1" /100) * "RE_ha" When ...
1
vote
0answers
16 views

Contour generation using Interpolation - Correcting edge Effects

I utilised the Interpolation feature in QGIS to prepare contours from a DEM I had generated. Sometimes when contours intersect the edge of the DEM area, they run along the edge for some distance. ...
0
votes
0answers
26 views

How to add new columns with attributes in existing Qgis layer?

How to add new columns with attributes in existing Qgis layer? Doing the "same thing" here described
3
votes
1answer
78 views

Reverting QGIS to version 2.2 from 2.4

I have QGIS 2.4 installed on a machine running Windows 7 64-bit "by accident". I was using 2.2 and when I added some package(s) it also installed the 2.4 version. Can anyone provide some advice with ...
0
votes
0answers
19 views

OpenGeo Explorer error publishing layers to geoserver

I want to use Opengeo Explorer to publish layers to geoserver but i am getting an error report. I create workspaces with no problems and i publish styles with no problems. Can you pls help? Error ...
4
votes
1answer
29 views

Can QGIS map canvas update while python script is running?

I want to automate a periodic refresh of the QGIS map canvas with updated shapefiles. A Python plugin or console script does not allow the map to update until the script terminates. Is there a way to ...
2
votes
2answers
45 views

Help projecting Austria data with QGIS

I'm trying to reproject this dataset from Austria Statistik Geodata. Data comes in "MGI_Austria_Lambert", and I'm trying to reproject to WGS84 What I'm doing is Saving layer as... and selecting ...
1
vote
1answer
25 views

Density slice/Colour slice in QGIS?

Can you do Raster Color Slices (like in ENVI) in QGIS? I.e. Where the histogram can be divided up into discrete units to represent different classes based on the values of the pixels.
4
votes
1answer
39 views

Is there a maximum length of pdf file QGIS composer can plot?

In QGIS 2.4 is there a maximum dimension in milimeters composer can produce while exporting to pdf? Trying to produce a 3000 x 900 mm or 2800 x 900 mm map. The QGIS composer displays all the map area ...
2
votes
1answer
58 views

Python console not working at all

My python console won't work at all. I can't open it. My QGIS version is 2.4. OS is win7 64. I've reinstalled QGIS a few times but I always get the same result. Strange. Something went wrong with the ...
4
votes
0answers
25 views

Workflow for adding Pipe Systems to QGIS

I want to layout a concept design for a sewer main in QGIS. I have a variety of background information: Aerial Imagery Services from various sources DEM from LIDAR Lot Boundaries I want to ...
2
votes
1answer
33 views

Using QGIS to access data delivered by ArcGIS for Server?

Can I use QGIS to access data delivered using ArcGIS Server? The following servers don't seem to be compatible with QGIS http://www.topofthesouthmaps.co.nz ...
1
vote
1answer
21 views

QGIS 2.4 Layout View pdf/raster file export moves points

I created a map, using a google basemap (openlayer plugin) and imported a table as a csv file (containing a name of a city, latitude, longitude for wgs84 and a row named "amount"). It displays ...
1
vote
1answer
20 views

Clipping a TIGER Census Tract by Vector Outline

So I have recently downloaded the 2011 Tiger Census Tract for the 5 Boroughs of Manhattan which I would like to process for a future visualization. The Tract Shp file includes water areas, which I ...
2
votes
2answers
32 views

Rasterize line shapefile

I'm trying to convert a line shapefile to a raster image at QGis, but my attempts have been unsuccessful. I've tried to use Raster/Conversion/Rasterize and SAGA/Grid - gridding/Shapes to grid, but to ...
1
vote
0answers
60 views

How to import a map consisting of pictures

I want to built some sort of Fantasy Map with Quantum GIS. The whole map is built out of 128x128 single pictures, 16384 in total. It should be a flat map. How do I import these pictures and align ...
1
vote
0answers
13 views

Annotation/Label size adjusting to map scale in QGIS

I'm trying to label the street names for a map I'm working on but I do not want the labels to automatically adjust to the map scale when zooming in or out. My question is: In QGIS how do I set a fixed ...
1
vote
0answers
24 views

GDAL WMS in QGIS 2.4

I'm trying to add in QGIS a layer shown here : propluvia When I watch in my console I see this request corresponding to the layer I need. The server is not able to respond to a getCapabilities ...
1
vote
2answers
48 views

Why is the data missing in my new shapefile?

I've made a new shapefile from a part of a attribute table. Marked all the rows that i needed and clicked on "save selection as", added the new layer in my project. All the data is missing, there is ...