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

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2
votes
1answer
446 views

How to load a postgres view using pyQgis?

Under Qgis 1.8 on Windows 7 I have this problem with my pyArchInit plugin: I need to load on the map canvas my geometries from a postgis layer. Till the 1.7.4 version I use the method explained on the ...
7
votes
1answer
2k views

Unable to Install External QGIS Plugins

I'm using: QGIS version 1.8.0-Lisboa on Windows XP, installed using OSGeo4W I am behind a proxy but I have configured it in Options > Network. When I go to Plugins > Fetch Python Plugins.. All of ...
0
votes
3answers
7k views

How to publish my map on the web? [closed]

I want to publish my map is created in QGIS 1.7.4 version on to the web.Can u pls suggest me how to publish the map with proper documentaion and screen shots if possible?
3
votes
1answer
258 views

how can I obtain the areas where my rasters overlap, using Qgis?

I have a bunch of raster files showing the distribution of different species of mammals, and I would like to obtain the areas where they overlap, the areas in whitch more than one species can be found ...
2
votes
0answers
174 views

Polygonize problem [duplicate]

Possible Duplicate: Polygonize function doesn’t overlay the shape file over the raster file When using "Polygonize" in Quantum GIS, I'm getting a polygon shapefile output that is a mirror ...
8
votes
4answers
1k views

How to run sextante algorithms outside of qgis python console?

I'm kind of stuck trying to figure out the way to run sextante from a standalone python from OSGeo4W distribution. The reason I want to do this is that I got tired entering parameters in the dialog ...
1
vote
2answers
402 views

Need help getting started with QgsComposition

I am using QgsComposition for the first time, but I fail at the first step :-( mapRenderer = iface.mapCanvas().mapRenderer() line 31, in mapRenderer = iface.mapCanvas().mapRenderer() ...
2
votes
1answer
410 views

How to add EPSG:5235 to QGIS?

First of all I should say I am new to EPSG and QGIS world.Then I want to Georeferced Raster image to EPSG:5235 in QGIS. But in Qgis I can't found above EPSG. How I add this EPSG to Qgis ? Pls help ...
1
vote
1answer
231 views

QGIS Projections

I am new to the GIS world and have faired pretty well with ArcGIS 9.3, learned and still learning on the job. I would like to get a better handle on QGIS though. I linked the files from my dropbox. I ...
5
votes
1answer
683 views

Qgis polygonize problem - DLL load fail

I have a raster file and I want to perform the method "polygonize". Then the problem occurs, that is shown on the screenshot. It doesn t have anything to do with the rasterfile format, I veryfied. ...
3
votes
2answers
3k views

How to add a google/OSM/bing etc style map layer to Quantum GIS

I am just getting started using QGIS. I am aiming to create a heat map of Census tracts in Georgia based on population. I have all of the data - the population for each census tract in Georgia. I've ...
7
votes
2answers
735 views

How to get latitude /longitude in Degree Minute Second (DMS) using QGIS field calculator?

I have come up with the following expression to convert 5.1234 to 5° 7`24.24" toint ($x) || '° ' || toint((($x) - toint ($x)) * 60) ||'`' || substr( (tostring(((($x) - toint ($x)) * 60) - ...
3
votes
2answers
653 views

How to create a polygon based on view extent in QGIS 1.8 ?

I am looking for a very simple thing. I want to create a polygon based on the current view extent of my project. In fact I want to 1) open google satellite layers 2) zoom to my area of interest ...
2
votes
3answers
507 views

Communication Between Browser and QGIS Server/QGIS API

Suppose I have QGIS server up and running with some vector data. Now a user accesses this data from a webpage. Would it be possible in some ways for the user to send a request to the QGIS Server and ...
3
votes
2answers
670 views

Normalize raster values to 0-255

I need to normalize the values attained from a band ratio to 0-255. I'm using QGIS. How do I do this? Any ideas?
4
votes
1answer
2k views

Performing Geoprocessing SQL Queries in QGIS from a PostGIS Database

This may be a dumb question, but is there way to run a PostGIS geoprocessing SQL query in QGIS? Specifically, I am thinking of running SQLs such as ST_Union, ST_Split etc etc. I have tried the ...
0
votes
1answer
281 views

How to convert the python plugins into dll file for QGIS application?

How to convert the python plugins into dll files for QGis application? Thanks in advance.
1
vote
1answer
504 views

Where is Table Manager in QGIS 1.7.x?

I would like to ask you, if is available funcionality like "Table Manager" for QGIS 1.7.x? I need to move fields in attribute table and then save changes. I don't see "Table Manager" or something ...
2
votes
0answers
198 views

How can I apply “natural breaks” classification to a raster symbology in QGIS?

Anyone knows how can I apply "natural breaks" to a raster symbology in QGIS? Cause I only see the "Equal interval" option.. I'm using QGIS 1.9
1
vote
2answers
127 views

Fetching field values from uncommitted features on Qgis

I'm trying to fetch a feature's field value on Qgis, I use QgsFeature.attributeMap().value(cont int & key).toDouble() This works fine for committed features but it always returns " 0 " if the ...
2
votes
1answer
380 views

QGIS apply style to shapefile

I'd like to create a Categorized style in QGIS, classify with it data in a shapefile and then save the shapefile with the new categorized style. Is it possible?
2
votes
0answers
180 views

QGIS: WMS misalignment

I am experiencing a small screen space offset when using a WMS layer (origin is GeoServer 2.1.4): The image shows a red square which is the top left pixel of a tile (GeoTIFF). An exact copy of the ...
1
vote
0answers
281 views

QGIS & WMS: Different aspect ratio between width/height and bbox

I am experiencing a small screen space offset when using a WMS layer (origin is GeoServer 2.1.4). Looking at the requests from QGIS (1.7.4) to my GeoServer I realised that the aspect ratio between the ...
1
vote
0answers
822 views

Which Open Source GIS Software is preferable either QGIS, mapWindow or gvSIG?

Which open source GIS software is preferable: QGIS, mapWindow or gvSIG. On the basis of: GIS analysis. Digitization. Quality checking.(Data correction). Store of data(i.e. storage in db as well as ...
1
vote
3answers
448 views

Automatically assign numbers to point file in various order in QGIS

I know how to automatically assign numbers to a new point files using the $rownum function in the field calculator. However it does it from the top-left over and down like reading a book. I could ...
0
votes
1answer
184 views

Will there be QGIS for Playbook?

Does anyone know if a mobile version of QGIS is planned for the Blackberry Playbook. I know there is an android version, I tried converting it to .bar and gave up when it wouldn't load because it ...
2
votes
2answers
390 views

QGIS Newbie Rendering Time

I am new to QGIS and have just installed 1.8.0 on a Gateway laptop that is about 2 years old. It is running Windows 7, has an Intel Core i3 2.13 GHz processor, 4 GB of RAM. I've just brought in my ...
2
votes
0answers
1k views

Qgis 1.8 fails to install

QGIS 1.8 will not start on Windows 7 Basically a similar issue as the above post. Version 1.8 fails to install with the standalone installer; with OSGeo4w, while it doesn't run into trouble during ...
1
vote
1answer
201 views

Map missing in map composer and when I print map

I am new to QGIS and am probably missing something but when I set up a new composer and add a map to the page nothing appears. I have pressed the render button and the up date with no results. When I ...
3
votes
2answers
244 views

Where to install python plugins without internet access?

I have a problem where I have no internet access. In the thread regarding a similar subject, it was mentioned that the plugin .zip file should be extracted to the ".qgis/python/plugins" in the home ...
6
votes
2answers
703 views

How to display an arrow pointing to a specific bearing in QGIS

I have a number of point features which contain an attribute I call "bearing" and another one called "slope". Each point has a bearing between 0 to 359 degrees. And the slope is either "+15" or "-15", ...
6
votes
4answers
7k views

How to export highlighted features from attribute table to an excel file?

When i selected some portion of the map in QGIS, in the attribute table the selected features gets highlighted... How to export the highlighted features from attribute table to an excel file ...
3
votes
3answers
2k views

How to define ITRF 92 and ITRF 2008 using Proj4 parameters in QGIS?

I know how to define a CRS, but this particular one is giving me a headache. I was unable to find the EPSG code at spatial reference. The main reason for asking this is that raster and vector data ...
5
votes
2answers
793 views

Is it possible to change the field length of a shapefile to over 255?

The maximum field length that I can specify is 255 and because of that I'm having problems with the input attributes, which have a size greater than 255. What alternatives are there for having longer ...
2
votes
1answer
727 views

qgis.core import error

I would want to use the Qgis api for custom desktop application. When I imported the qgis.core module, I get the following error >>> import qgis.core Traceback (most recent call last): ...
1
vote
2answers
1k views

QGis problem with raster transparent

I am new to QGIS. I found the problem impossible to solve the parts of raster data that are in TIFF format should be made transparent. What do I do?
1
vote
0answers
316 views

Trouble getting lat/lons from point layer

I am following this post about how to get lat/lon information from a point file, but without success. Does this metadata posted below provide information that changes the prescribed method for ...
5
votes
1answer
433 views

Is it possible to perform 3D vector editing in QGIS?

I've searched the manuals and plugins and done some tests.. Is it in any way possible to perform 3D drawing and editing of vector objects for 3D mapping e.g. in a 3D shapefile or PostGIS 3D table?
2
votes
2answers
3k views

QGIS 1.8 will not start on Windows 7 [closed]

I have downloaded QGIS 1.8 and installed it on my windows 7 system. When I click on the desktop icon, nothing happens. I am currently running QGIS 1.7.4 with no problems and the installs of previous ...
4
votes
3answers
6k views

How to import info from mdb file?

I need to import info on a QGIS project. The info are in a MDB file (population, mean age, number cars and so on per Town) that is possible to connect with a region shape from an ID (the ID is the ...
1
vote
0answers
244 views

What do I need to build a C++ plugin on windows 7?

I want to make a plugin in C++ and I need to write and build it in windows (Im better with *nix systems). While I have skimmed the various updated C++Plugin docs I can understand if I need to build ...
6
votes
3answers
1k views

How to group elements in QGIS legend side by side?

I would like to edit the legend in my map so that the entries of two polygons will appear together, i.e. the two entries in the legend should be displayed appear as "Study area and possible study ...
1
vote
0answers
392 views

Importing GPS coordinates correctly

I am importing a gsx set of waypoints with lat/lon taken in degrees, minutes, and thousandths of a minute. When they are added to my project, the waypoints are not showing up correctly - the ...
1
vote
1answer
227 views

QGIS Updating composer label text via python - problem with Item Properties panel

I am writing a plugin that replaces the text of a composer label based on its itemID. When I change the text of the label using: item.setText("Hello World") the label changes on the composer but ...
2
votes
1answer
1k views

Convert area from square meters to degrees globally

I have a global raster file with 3600x1800 pixels. I don't have any information about the projection used. The raster contains one band with a quantity with the unit "per square meter". How can I ...
5
votes
4answers
7k views

How do I load a .dbf file into QGIS?

I want to use QGIS to extract lat/lng data from the vertices of polygons. There are about 400 polygons, each with maybe 200 vertices. I am having trouble with step one, getting the data into QGIS. ...
1
vote
1answer
3k views

QGIS Web Client installation procedure

I have QGIS Server up and running and can successfully load WMS layers back into QGIS. I am attempting to set up the QGIS Web Client. Procedure: https://github.com/qgis/qgis-web-client I am having ...
2
votes
5answers
2k views

Is there any way to extract coordinates of a road segment using QGIS?

I add my own road vector data on top of Google map using open layers plugin with QGIS. The vector layer is generated using PostgreSQL DB. Is there any way to extract coordinates of a road segment ?
4
votes
1answer
335 views

Looking for a SVG library for construction

Would anyone be able to suggest a good library for svg symbols for construction please? To be used in QGIS. Ideally water and pipeline network symbols. ciao
6
votes
1answer
536 views

PostGIS query vs QGIS filter

I have a PostGIS dataset with around 3 million shapes. I only need to view about 1,500 of these shapes at any given time, but the shapes I need to see depends on which feature is selected in a ...