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

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5
votes
1answer
558 views

How to handle spatial join 10 chars field name limit?

When I try to perform a spatial join between a point and polygon file, I get a notice saying spatial join will not be performed because following field names exceed 10 Characters. Kindly help to ...
2
votes
1answer
959 views

How to draw lines, dashed lines, routes and add images to the QGIS mapcanvas?

I need to draw a rectangle in a map canvas and inside it draw routed dashed lines and add small images to it. These actions are to be performed using the QGIS API. Is there any place with examples ...
1
vote
1answer
398 views

Adding table from Postgis

While trying to import a table containing raster data in QGIS , Raster column is not being imported ... I am getting following messages: Database connection was successful , but the accessible ...
1
vote
1answer
741 views

QGIS WMS ver 1.3.0 Exception with GeoServer

I'm trying to load WMS layers from a local GeoServer into QGIS so that I can edit them. I can access and edit the same layers if I access them directly from a PostGIS database. However, trying to load ...
11
votes
5answers
5k views

How can I map a matrix of origins and destinations in QGIS?

I have a central point on a map, and I have other points in a separate layer (the location of a venue, and the origin cities of the venue visitors). Is there a plugin which would generate output ...
2
votes
1answer
341 views

How to connect QGIS to a WMS-C with python?

I would like to connect my QGis to a WMS-C server when my python plugin load. How can I do that ? BTW, the method: addRasterLayer do not seams to handle WMS-C layer...
9
votes
2answers
2k views

Trouble with graduated symbols after joining shapefile with csv file

I have successfully joined data from a csv file to a shapefile in QGIS but for some reason I am having trouble symbolizing my data. I want to use a graduated symbology however this option is not ...
7
votes
2answers
8k views

ECW for QGIS 1.8 in Ubuntu 12.04

I have followed various online help guides on how to make ecw for QGIS 1.8 work in Ubuntu 12.04. I had it all working in Ubuntu 10.04 but since migration to 12.04 no such luck. Is there a guide that ...
3
votes
1answer
459 views

Use QGIS to visualize OpenStreetMap data

I have a osm map for a certain region. Also using osm2po I extracted the graph which includes edges and nodes into the database. Now I want to visualize the map and then visualize the shortest path. ...
2
votes
1answer
131 views

Reproject an aerial layer in QGIS and then open with ArcEngine?

I have an Aerial layer (.SID file) which I would like to re-project in QGIS, then I would like to open it in ArcEngine. I've figured out how to do this with vector layers in GGIS, its just a right ...
2
votes
1answer
534 views

How Can I get the Open Modeller plug-in for Quantum GIS 1.7.4?

I would appreciate if you can tell me to install the plug-in of Open Modeller in Quantum GIS 1.7.4. It is not in the list of plug-in in the spanish version of the QGIS. Thank you,
2
votes
1answer
3k views

How to find polygons centroids? [duplicate]

Possible Duplicate: Get list of coordinates for points in a layer? Sorry for another basic question - my map is almost done but now my boss wants me to enter new outbreaks (that we don't ...
2
votes
1answer
207 views

After re-open of old project file, several layer selections no longer available

I'm new to QGIS. I created a QGIS project, loaded 1 to 3 shapefiles via Add Vector Layer (from 2008 TIGER/Line Shapefiles http://www2.census.gov/cgi-bin/shapefiles/state-files). The maps look fine ...
4
votes
0answers
754 views

Does QGIS have these CAD editing functions? [closed]

I tried QGIS for the fist time today and it seems quite capable for the task that I have in mind. However, I really miss some basic editing functionality from another GIS software that I have to use ...
11
votes
1answer
594 views

QGis raster terrain analysis - The curvature filter puzzles me

I am a french Master student at university Grenoble INP, and during my master project I have worked on DEM (raster) terrain analysis. Thus, I have read the source code of several QGis-1.7.4 raster ...
4
votes
1answer
516 views

How to add attribute data up?

Sorry if this question is too simple/easy for you guys, but I'm still learning QGIS and pretty much teaching myself where I can. Is there a way to add data from 2 columns into one new column inside ...
1
vote
0answers
692 views

Symbol rotation by using rotation-field [closed]

I want to rotate my symbols using the rotation-field in my atribute-table. After choosing the rotationfield, my symbols become invisible (the text is still there). What happend? Thank you! Martin
2
votes
1answer
6k views

Convert a Tif raster file to vector shp file in QGIS

So I've been trying to convert a georeferenced Tif raster file into a vector shp file using QGIS. It's seems to complete this but it ends up giving me a feature class that has over 500,000 features, ...
2
votes
0answers
142 views

Does QGIS preserve Feature Class Relationships (1to1 or 1to many or Many to many relationships)?

Does QGIS preserve Feature Class Relationships (1to1 or 1to many or Many to many relationships) and can the related attributes be clicked and viewed through the identify feature tool?
11
votes
4answers
5k 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 ...
1
vote
1answer
2k views

Projection in QGIS - Scale bar and measurement

When I load a *.csv file (delimited text) as a layer in QGIS, the scale bar shows degrees (for example 0 to 10 degrees). When I uncheck On the fly projection and change the units for feet or meters, ...
6
votes
1answer
476 views

How to find the shortest path within a polygon? [closed]

I am trying to find a way to calculate the shortest path from one point to another without crossing the boundaries of a polygon. I would like to do it with QGIS as I do not have access to ArcGis. It ...
4
votes
2answers
831 views

How can I add OpenLayers layer from the python console?

I am new to the python console. How can I add a layer from the OpenLayers plugin from the python console? Thank you
2
votes
2answers
618 views

How to recreate Mapinfo labels in QGIS?

I try to convert a mapinfo tab-file containing textobjects wich are positioned and rotated in mapinfo into a shapefile or something similar without loosing all information. All information is located ...
5
votes
1answer
5k views

Trouble exporting from QGIS to Illustrator

I am having trouble getting my files to transfer or export to a vector file. When I open the file in Adobe illustrator there is a lot of information missing. I have tried to "save selection as a ...
2
votes
1answer
204 views

Qgis C++ plugin translation

I'm having issues with the translation of my Qgis plugin. static const QString sName = QObject::tr( "Editeur Monoscopique 3D" ); MyClass::MyClass( QgisInterface * theQgisInterface ): ...
2
votes
1answer
672 views

How to display local file's geometries as rubber bands in QGIS

I'd like to get geometries from a local file (e.g. GML) displayed as rubber bands (QgsRubberBands) in QGIS. However, I wouldn't like to load the layer into the map because in the real scenario there ...
23
votes
1answer
18k views

How to install a QGIS plugin when offline?

Due to various IT policies at my workplace, QGIS is installed on a machine that is not connected to the internet. I wish to install a couple of QGIS plugins on this system. I have downloaded the ...
2
votes
3answers
638 views

vector tool missing when install QGIS 1.7.4 on new computer

I installed QGIS version 1.7.4 a few months ago. Under the menu Vector > Data Management Tools I have two options to make a join: 'Join Attributes' and 'Join attributes by location' (see screenshot). ...
3
votes
1answer
1k views

How can I add a grid (from projection MTM8) on my layers

I need to add a grid on a map I created with my own layers and GPS data. How can i do this? I know how to do it in Arcgis, but not in QGIS.
2
votes
1answer
382 views

How do you calculate positional accuracy in qgis?

How to you compare two layers in QGIS to get the positional accuracy?
1
vote
0answers
151 views

How to call a PNG file with MapServer and a Google base layer? [closed]

How can I call a png file from map path including a Google map as base layer? I'm working with MapServer and I have some shapes made with Quantum GIS and ArcView. I can call those shapes in a url and ...
2
votes
3answers
1k views

Transforming Visio polygon to shapefile?

I am a complete newb at this stuff and don't know what I don't know. I may use incorrect language. Essentially, I want to convert the shapes in a Microsoft Visio diagram into a shapefile. I pretty ...
6
votes
2answers
1k views

How to copy a group of layers between QGIS projects?

In ArcGIS I am used to being able to have a couple of MXD documents open and copy-paste groups of layers from one MXD's table of contents to another. This can save a LOT of time ensuring consistent ...
14
votes
8answers
10k views

How do I create a shapefile showing footprints of Rasters?

I have around 1,000 satellite images in tiff format, and I want to create a shapefile which will serve as an index to the rasters. This is something similar to a raster catalog, but I do not want to ...
4
votes
1answer
1k views

How to style a layer from console?

I am new to the QGIS python console. I am trying to load a raster layer from the console, set the crs and a specific style from a qml file. layerPath = os.path.join(raster_dir,raster_name) fileInfo = ...
3
votes
1answer
212 views

Create new polygon layer based on areas of varying numbers of stacked polygons

I have several species range maps (as polygons) that overlap/stack. From this, I am trying to identify areas of highest biodiversity. Ideally, I'd like to create a new polygon layer, where 1 part is ...
2
votes
1answer
94 views

“Find by attribute” plugin error

This is the error message, when launching the plugin. I hope this is the right place, where to report this kind of message. Any help would be appriciated! An error has occured while executing ...
6
votes
2answers
1k views

Can QGIS preserve layers when exporting a PDF? [duplicate]

I saw this posted about a year ago (Can QGIS preserve layers when exporting to PDF?) but figured it was worth asking again -- is this possible? My usual workflow with ArcGIS is to export to AI then ...
3
votes
1answer
3k views

How do I clip/mask a satellite photo to a polygon?

Given a shapefile composed of contiguous polygons, I'd like to clip (or mask) regions of satellite photo to the polygon outlines, and export each resulting raster in medium resolution for further ...
1
vote
2answers
3k views

How do I open a shapefile in QGIS for upload to Garmin GPSmap 62?

I now have a polygon and have succesfully raised 25 random sample points and saved as a shape file. I have checked that GPS utility and the shape file are set at 27700 BNG but when I try and open the ...
1
vote
1answer
392 views

Rasterize difference between QGIS and FWTools

I am wanting to use FWTools to rasterize a large number of Shapefile polygons. I have used the Rasterize tool in QIS and it works great. But when I use the generated code in FWTools the process does ...
0
votes
1answer
895 views

Problem adding WFS Layer to QGIS project

I want to load data using an WFS into qgis 1.7.4. After connection to the server is established, data seems to be downloaded, but no data is displayed in qgis, neither geometry nor attributes. The ...
0
votes
1answer
116 views

QgsLegend link error when building

I'm developping a software using QGIS. When building my software there is a LINK error. 1>mainwindow.obj : error LNK2019: symbole externe non résolu "public: __thiscall ...
2
votes
1answer
186 views

Sandbars feature extraction from satellite image

I want to know if we can analyse the permanancy of sandbars from a satellite image? Whether the formation of the sandbar is permanent or temporary.
3
votes
1answer
225 views

Is it possible to change the year range of time manager in QGIS?

I have a shapefile with a start and end time field, properly formatted. However my dates range from 1864-1995. When I try to use the shape file with the QGIS time manager plugin I keep getting this ...
1
vote
1answer
412 views

Quantum GIS Garmin Maps62 device and GPS utility - making a polygon for random point

I have a Garmin GPSMaps62 unit and GPS utility. I have logged tracks and need to get these to load as polygon layers in Quantum so that I can then ask Q to give me random sample points and upload ...
12
votes
4answers
3k views

How to place elevation numbers on contours with uphill orientation and position?

I want to orient my elevation labels uphill. Is that possible? I'm currently using the labeling tool from QGIS (not that one in layer settings). I want the labels curved and uphill oriented (and I ...
5
votes
3answers
2k views

How to generate colorful images using GDAL?

I am using gdal_translate -of JPEG -scale -co worldfile=yes ndvi.tiff output.jpg command to convert tiff images to jpg and resize it. But it generates only black and white images. How can I generate ...
3
votes
2answers
868 views

How to study qgis generated tiff images for water flow/resources ?

I am new to qgis. I have created tiff images from modis data using qgis. I want to study the water flow/resources from those images. As I am new to this field I don't understand how to study those ...