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

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2
votes
0answers
201 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
128 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
386 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
182 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
290 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
838 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
467 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
405 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
208 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
247 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
734 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
835 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
738 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
321 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
439 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
399 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
235 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
345 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
548 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 ...
2
votes
1answer
825 views

What happened to Live GPS Tracking in 1.8.0-Lisboa?

Dang, I was just getting used to Live GPS Tracking in 1.7.4-Wroclaw. I downloaded the new version 1.8.0-Lisboa on another computer. The Live GPS Tracking thing was in the View pull-down menu in ...
1
vote
2answers
1k 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 ...
3
votes
0answers
302 views

Freehand plugin query

I've installed the QGIS 'Freehand' plugin and I have a query regarding it. When drawing a polygon qgis automatically closes the polygon when the pen leaves the graphic tablet. Is there any way to ...
1
vote
2answers
916 views

How to access vector coordinates in GRASS GIS from python?

Is there a way to iterate over lines and their vertices using python? I'm new to GRASS GIS, and it looks like there are ways to read raster (for numpy), but I don't see a direct way to access ...
2
votes
1answer
1k views

Basic User Questions: Tracing a Border in QGIS

The project: I'm plotting a dilapidated cemetery, I'm using GPS waypoint data to plot the headstones in QGIS. The map I'm making is to show the orientation of the graves, and who is in them. I ...
3
votes
2answers
5k views

Calculating the minimum distance between points and polygons in QGIS

I have two vector layers: one point and one polygon and I want to calculate the minimum distance of each point from the polygons (ie the distance from the closest point of the closest polygon). Is ...
1
vote
1answer
922 views

Concatenate Fields into One Field in QGIS

I have seen some posts on this, but only for ArcMap. I am looking to take a range of values from two fields and concatenate them into one field to make a unique value. For example: XMAX YMAX ...
4
votes
1answer
863 views

How to reclassify in Rastercalc?

I now need to reclassify, I'm using rastercalc... but I can't get the syntax right!! I need that values >0 become 1 I found this example... eq( [relief]@1, [mask]@4, 150 ) so I tried: ( [raster A ...
5
votes
1answer
1k views

How to perform Ordinary Kriging in SAGA via QGIS SEXTANTE Plug-in?

I'm trying to learn how to apply the kriging analysis in QGIS using the SEXTANTE plug-in and SAGA tools. It appears that I have my SEXTANTE and SAGA folders configured properly according to the user ...
0
votes
1answer
223 views

How to find embedded Coordinate Reference system in a Layer

I want to find CRS in an added shape file. Ex. In Arc GIS if we go to Layer Properties and Source we can find embedded CRS to a layer. How to find in QGIS, embedded CRS ia a layer/ Shape file??? I ...
5
votes
1answer
2k views

Features to 3D from 2D in QGIS

Is there a way to convert 2D features to "3D" features in QGIS? I know there is a way to do this in ArcMap by using an attribute value in the attribute table, but I am looking to do this with ...
2
votes
1answer
214 views

How can i include program form (created in Designer ) to my QGIS plugin?

How can I include a form created in Designer in my QGIS plugin? And how to get controls values (textbox,label,etc)?
2
votes
1answer
1k views

How can I add button to the QGIS toolbox or create my own toolbox?

I want to create a button and add it to the QGIS toolbox or alternatively create my own toolbox and add the button here. A plugin should be started when the user clicks the button.
1
vote
0answers
2k views

download and installation of sample data [closed]

I have downloaded the sampe dataset under "my documents". When I extract the contents of the zip file, the only folders that are actually installed, are "gml", "gps" and "shapefiles". Thus, ...
0
votes
1answer
1k views

How to install sda4pp plugin with missing repository in QGIS

I see that the repository for the sda4pp plugin went down in 2011. Does anyone know if there is another way to download the plug-in with the repository missing? If this plug-in is no longer ...
2
votes
1answer
206 views

Can't load PYQGIS

I get this error; any comments Couldn't load PyQGIS. Python support will be disabled. Traceback (most recent call last): File "", line 1, in ImportError: ...
4
votes
1answer
158 views

Where are the Spatialite settings stored?

after moving a spatialite-database to another directory, qspatialite says "Can't connect to Database" / Error unable to open database file. Even no project is open or I try to create a new project. In ...
5
votes
5answers
9k views

How to break a single polygon into multiple polys?

I created voronoi polygons after which I dissolved them on the basis of one attribute. Now there are cases where in for one single attribute "abc" I have3 polygons at different places with same object ...