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

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2
votes
1answer
169 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
371 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
111 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
185 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 ...
10
votes
2answers
17k 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
565 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
168 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
6k 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
292 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
12
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 ...
5
votes
1answer
974 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
284 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
2k 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 ...
6
votes
3answers
716 views

How to extract area programmatically?

is there a possibility to extract the area covered by one geometry of a shapefile (polygon)? I tried with thepoly.area() but get "nan" as result. Ok. I think you are right and there is ...
2
votes
0answers
581 views

Is there an Offset function in QGIS for Polygons?

IS there an offset function in qgis similar to that in autocad for polygons. I have an irregular shaped pollygon which i want to offset at 100m out from the edges, effectively adding 100m out each ...
5
votes
2answers
4k views

How to install QGIS on Centos 6?

I'm new on this; I really tried a lot before ask.. but nothing works. I did all that the qgis page says. Install ELGIS. after that i investigate and tried diferents comands.. but nothing works..the ...
6
votes
1answer
5k views

How to measure area correctly?

I have now used my entire evening, but I can't figure out how to make areal calculations (eg. in km2). I have tried the 'field calculator', I have tried the 'measure area' function on the "attributes" ...
21
votes
4answers
3k views

How to calculate terrain Curvature?

I have an elevation raster and I would like to get some basic terrain variables, such as slope, ruggedness, aspect or curvature. The problem is that I don't seem to have the possibility to calculate ...
3
votes
3answers
1k views

How to join Shapefile and Excel data without unique ID column?

I have one huge shapefile with lots of roads (polylines) along with various attributes and I have an Excel file containing some of these roads by three same attributes (road no., section no., length) ...
4
votes
1answer
110 views

Why are selected features not highlighted in OSM layers?

I am experienced with GIS, but new to QGIS and Opensource data. I recently opened an Open Street Map (osm) file in QGIS 1.8 (on Kubuntu 12.04). I found that when I selected a feature, there was no ...
2
votes
2answers
2k views

How to classify/style rasters correctly?

I am using a GeoTiff raster data and trying to classify it. I was wondering what are the techniques that I can use in QGIS to do this? The raster I have looks like but I tried the reclassify tool ...
1
vote
1answer
348 views

How to connect QGIS to an online database on Mac OS X? [closed]

I'm a real beginner/dummy when it comes to QGIS and online databases. I have tried a variety of things trying to connect to Spatialite, PostGIS and MySQL but all attempts have failed due to my lack of ...
5
votes
2answers
596 views

Setting up an online map site [duplicate]

Possible Duplicate: Steps to Start Web Mapping I have taken on setting up a database which stores information of an annual country-wide survey of alien aquatic weeds, linked to a GIS ...
1
vote
1answer
328 views

How can I import geometries from an invalid GML quickly?

I have the following gml geometry : <gml:Polygon xmlns:gml="http://www.opengis.net/gml" srsName="EPSG:2154"> <gml:exterior> <gml:LinearRing> <gml:posList ...
3
votes
2answers
905 views

How to use SAGA Kriging in Sextante for QGIS? [duplicate]

Hello, I tried to use SAGA (Ordinary Kriging) via SEXTANTE in QGis. The Sextante log tells me the following problem. Does anyone have a solution for my problem? By the way I'm usually a SAGA user but ...
2
votes
1answer
195 views

Qspatialite plugin problems with queries using inner join

I'm trying to create a layer in QGIS from a sqlite database using a query from 2 tables: one has spatial data and the other doesn't. When I build the query using Qspatialite using the 'Advance SQL ...
4
votes
2answers
904 views

GPS-Plugin and Garmin data

I am an avalanche specialist and I use a GPS Garmin 62 for fieldwork. I for example use waypoints to measure snow depth in avalanches for volume calculations. When I add a waypoint in the garmin ...
4
votes
2answers
420 views

How to iterate over selected layers?

In QGis by pressing shift or ctrl keys a user can select multiple layers in toc. How can a python script iterate over selected layers? I'd expect a iface.selectedLayers() but I can find only ...
6
votes
4answers
6k views

Qgis - Is there a way to split a polygon layer with a line layer?

I am drawing administrative regions that have boundaries follow streets in another layer. As these streets are pretty long with many vertices, I don't want to re-trace them. I am looking for a way to ...
5
votes
0answers
381 views

What to do about Geoserver WPS Warning “Could not get a ServiceInfo”?

This is the warning i am getting when i try to use this WPS service from QGIS, and the processing take a long time, but doesn't terminate, what might be the problem? 17 Oct 12:33:25 INFO ...
5
votes
2answers
1k views

Where can I get information on QGIS beta versions?

While searching for information on some qgis functionality on the web, i noticed several times, people using version 1.9, however this version is probably some beta (or so i thought) but i cant seem ...
0
votes
1answer
919 views

How to create a custom projection of PRS92 and UTM 51N for the Philippines? [duplicate]

Possible Duplicate: How to define new custom projections in QGIS? How do I create a customized CRS parameter in quantum GIS? I'm try to create a projection of PRS92 and UTM 51N. This ...
3
votes
2answers
382 views

Can I Dynamically Update Symbol Ranges?

Background: I'm currently trying to dynamically change the ranges for a layer with new style graduated symbology. Problem: I thought it may be as simple as updating the ranges for the existing ...
1
vote
2answers
168 views

Has Action behaviour changed between 1.7.4 and 1.8.0?

I have an Action that loads raster layers (.jp2) into the current QGIS window. This action has been working great in version 1.7.4. I have now upgraded to 1.8.0 for many reasons, but the same Action ...
0
votes
3answers
777 views

Run function if item in QComboBox is selected

I got another issue writing a plugin to convert three shape files into an .obs input file. I created a UI (Qt) with a QComboBox to select a layer (that works fine). As soon as one of the layers in the ...
1
vote
1answer
243 views

Count the number of symbols in a 'new symbology' renderer from pyqgis

Background : I create a lot of symbology using 'saturation' ramps - for want of a better term, e.g. where the hue and value of each symbol stays the same, but the saturation changes. I couldn't figure ...
4
votes
3answers
2k views

How to sum raster image values with vector overlay

I'm new to this and haven't been able to figure out how to do this on my own. Here's what I want to do ... I have two files: a raster image of land use data and a vector-based shapefile of my ...
3
votes
3answers
1k views

QGIS How to use Query Builder with a Joined table

When I join a layer with another layer all the attributes are correctly displayed in the first layer. However when I use the Query builder (Layer - Query) and then use Zoom to layer, nothing is ...
0
votes
1answer
3k views

function, return, 'instancemethod' object has no attribute '__getitem__'

I'm still trying to write a python plugin to create an input file for an urban climate model out of three shape files. Now I stumbeled into another problem, that I think is an easy one, but I just ...
7
votes
1answer
359 views

How to migrate SVG-based styles for QGIS to other computers?

I'm working on a project that has involved creating many recolourable SVG icons and bringing them into QGIS. These are then used in layer symbologies, with these subsequent layer styles exported as ...
3
votes
3answers
9k views

Editing a KML file or converting KML to Editable format with attributes

I'm using QGIS. I'm trying to either edit a .kml file someone else created in Google Earth or convert it to another editable format (like a .shp file). I've read the following threads without really ...
3
votes
2answers
182 views

Can I Combine Areas in Quantum GIS?

I am working on a provincial annual health bulletin. I have a .shp file that has GIS data about the smallest divisions called "GN Area". Two or three GN Areas form one MOH area. I want to get the ...
1
vote
1answer
214 views

Analyse spatial data and extract results in tabular form in QGIS

I'm sorry if this question is badly framed, I only started with GIS and QGIS 2 days ago so I don't know any terminology yet - I'll try to explain as best I can. I have 2 layers in QGIS (1.8, on ...
4
votes
1answer
3k views

Installing QGIS on Mac OS 10.7. “The GDAL framework is required.”, and yet I have it

what did I miss? I'm trying to install QGIS on my MacBook (Mac OS 10.7). I'm following these instructions: https://sites.google.com/site/eospansite/qgis-installation/installing-qgis-1-6-on-macosx It ...
2
votes
1answer
991 views

How to fix The procedure entry point squlites3_open_v2 could not be located in the dynamic link library squlite3.dll? [duplicate]

Possible Duplicate: How to fix QGIS error “Entry Point could not be located”? I downloaded QGIS to my laptop (Window 7 64b) yesterday but when I click on the desktop logo I get the ...
1
vote
0answers
625 views

How to reproject a raster in QGIS? [closed]

I wanted to reproject raster file from UTM to decimal degree in QGIS version 1.7.1 or 1.8.0.. I could reproject one raster file before in QGIS Version 1.8.0. I have tried again, but now we cannot ...
16
votes
2answers
14k views

How to reproject a vector layer in QGIS?

I have some shape file which is in UTM. I wanted them to convert to Decimal Degrees in QGIS. Thanks.
2
votes
1answer
301 views

Hyperlinking to PostGIS Layers and Zip files with QGIS Actions

I previously asked a question about hyperlinking data in QGIS that gets loaded into QGIS (see post: Hyperlinking in QGIS - Add Data to current window). A user provided me with the code, which works ...
2
votes
0answers
62 views

QGis, add dialog and classes to plugin

what are the steps to add files that represent a uidialog(draw with QTDesigner), and add the necessary python class files, using the default makefile provided with qgis plugin builder? thanks,