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

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4
votes
3answers
284 views

How to compute the outline of multiple tracks?

I have multiple gps tracks with depth data gathered from the lake. The tracks are overlapping/intersecting. I want to get an outline polygon. I have a multi-line shp. I've tried to diffuse it in qgis ...
1
vote
0answers
111 views

GeoTIFF Mosaic/Crop/Translate in QGIS?

I routinely have to mosaic multiple GeoTIFFs together, extract a rectangular area, and save that area as a JPG with a world file. Typically I've been using commercial software for that (Geographic ...
2
votes
1answer
52 views

Resolve polygon parent relationship in QGIS

I have a layer in which, following geometry processing, the polygon of a zone that is a full enclave to another seems to have become its child object, which I think will cause problems down the line. ...
1
vote
2answers
196 views

Any difference between EPSG:3003 and EPSG:102091?

I am working on QGIS 2.2.0. The PRS I am working on is Monte Mario / Italy zone 1 (EPSG:3003), with the following parameters: PROJCS["Monte Mario / Italy zone 1", GEOGCS["Monte Mario", ...
1
vote
1answer
367 views

How to get QGIS layers style in a single file

I have layers on my QGIS project. Rivers Water pipes Gas pipes ..... I set the color, width, size of these layers. All layers are different style. I want to use these styles in geoserver. I have ...
0
votes
2answers
92 views

Is there a way to run spatial join within tolerance?

I have some data that should be spatially joined, but from small precision differences (less than 1 in) they aren't joined. I've found no way to add tolerance to qgis spatial join operation. Is there ...
0
votes
0answers
142 views

Is it possible to get WMS feature info for the WMS layer in the QGIS web client?

When I load a wms layer in qgis, it's possible to get feature information. When I open the web-gis-client on my server, it's possible to get feature information for all layers but not the wms layer. ...
0
votes
1answer
41 views

QGIS GRASS vector simplification creates duplicate data rows

When simplifying polygons in QGIS (2.2.0) with the GRASS v.generalize tool the resulting layer duplicates some data rows many times. A shapefile of 657 zones/data rows: .. is simplified to one ...
1
vote
0answers
67 views

Is it possible to customize openFeatureForm of pyqgis?

I am a beginner in PyQgis. I am trying create a plugin, which will be used to AddFeatue,Delete Feature, and Edit the Feature. It is more customized than which is provided by Qgis (2.2). I am capturing ...
2
votes
2answers
190 views

How to get features based on their attributes using Python - special characters?

I want to get features based on their attributes and it works fine when I use this Python script: canvas = iface.mapCanvas() curLayer = canvas.currentLayer() it = ...
0
votes
2answers
228 views

How to show attribute table in the form

Is there any way to show the attribute table of a layer in a QtextBrowser or a QtableView on form? I did this but,(shows attribute table in a separate dialog) I have no idea, how to show it in my ...
3
votes
1answer
630 views

How to find the id of the last added feature using pyQGIS?

Is it possible to programmatically (in python) access the attribute info of the last added feature in QGIS 2.0 before edits are saved? I'm failing to find a way to get the ID and subsequently other ...
0
votes
0answers
36 views

Openstreet map loosing information

I succesfully created a shapefile from openstreetmap with the OpenStreetMap tool in QGIS 2.2. When I try to create a polyline layer, it says that there are 8000 values in the db file for the property ...
1
vote
1answer
155 views

draw extend of print composer map as rectangle in canvas

After defining the extend of my printed map in the printcomposer I can show the map center in the canvas by hitting "view extend in map canvas". So far so good. But is it also possible to show the ...
0
votes
1answer
58 views

Enhance the color associated with a band od an aerial photo?

I am using QGIS 2 on Windows 7 and have 4-band aerial photos loaded in to a project. I have switched the bands in order to make the photos display as color infrared. Does anyone know if you can ...
8
votes
1answer
1k views

Is the use of Google Earth imagery via the OpenLayers Plugin in QGIS legal?

I understand the terms and conditions WRT use of Google Earth imagery in external applications are strict. Years ago ArcBruTile offered such service in ArcGIS the legallity of which was ...
0
votes
0answers
36 views

Copy queried attributes of a shapefile to a new shapefile [duplicate]

I have a polyline-shapefile, which I have successfully read into python using pyshp module. My problem is to save the 2nd node of every line feature into a separate, single point file. I have ...
2
votes
1answer
185 views

How to generate routes that follow underlying road network?

I have a set of points (~2300 bus stops) and I have a network of roads that these bus stops lie on. When I have a bus route that goes from A to B, how do I generate the route such that it follows the ...
1
vote
1answer
81 views

Project one layer in qgis using projection CRS of another layer

I am using QGIS 1.6 and have imported a set of latitude, longitude points from a csv file as a layer. I also have another layer from a shape file. When I go to layer->properties for the second layer I ...
1
vote
1answer
143 views

QGIS custom action and button toggle

I've added a custom toolbar with some buttons to my QGIS 2 plugin. I'm wondering how to get the button toggled (pushed in-looking effect) using Python. I've gotten this to work for existing buttons ...
1
vote
1answer
121 views

Both dashed line and stroke line in parallel in the SLD

I just started in GIS. how can i draw in the GeoServer's SLD editor, both dashed and stroke line in parallel? like this, ----------------------------------- ___________________________________ ...
0
votes
1answer
98 views

PostGIS Group By Error [closed]

I am performing a pretty simple query in PostGIS 2.1.1 from within QGIS 2.2 for Windows (using the DB Manager plugin). I have a table with many columns and I am trying to perform a Group By function. ...
1
vote
2answers
67 views

PostGIS schemas doesn't show in QGIS

I try to use QGIS to display some data stored in PostGIS, some of schemas don't show except public; And it's a testing DB, so I have only one super user: postgres. I use PostgreSQL9.3. Anyone has some ...
2
votes
1answer
2k views

How to change GDAL version in QGIS to get ECW import to work

I’ve previously been successful in importing ecw into QGIS 2.0 but the same methods (for example How to add *.ecw files to QGIS 2.0 on Windows?) have failed with a fresh install of QGIS 2.2 with ...
1
vote
1answer
902 views

Exporting geodata from QGIS to Esri File Geodatabase?

For a project I need to create a set of vector data that I think I could do in QGIS. However the customer demands that the final data set needs to be delivered in a Esri File Geodatabase. Is there ...
0
votes
2answers
1k views

SLD parsing fail on GeoServer

I created a custom style on QGis and saved as SLD file. When i added to GeoServer, after validation it, i got an errors about parsing. Parsing failed for Filter: java.lang.RuntimeException: Unable ...
0
votes
1answer
158 views

QGIS and Oracle Spatial database - rule based system in future version?

I (a geographer not to familiar with IT stuff) want to start a pilot with QGIS at a municipality I work for. We store our data in Oracle databases. When trying to open these databases (QGIS 2.2) using ...
0
votes
1answer
236 views

How to use a .qpt made in another project?

I'm trying to make maps in print composer of several different projects. I would like the maps to look the same, just for different areas, so I tried to use the .qpt that I made in the first project ...
2
votes
1answer
53 views

How to display information when a certain dataset is loaded into QGIS?

I need to show the quality information of a dataset that was manually created by me, that is saved as a text file. The text file will "pop up" when the dataset is added into QGIS. I have no experience ...
0
votes
1answer
148 views

QGIS: Comparing 2 attribute tables to discern unmatched attributes

In QGIS, I am trying to compare two different attribute tables. One is simply the updated version of the other. Each feature has a unique identifier. How can I return the number of unmatched records? ...
0
votes
1answer
141 views

change the direction of the marker of a line in QGIS

I have a map with three lines. Each has a marker on it. I would like to reverse the direction of the topmost marker. So I open Style dialog and enter the expression "direction" * 180. The value ...
4
votes
2answers
136 views

“Levelling” elevation data coinciding with polygon?

I have a shapefile containing building geometries (polygons) and a elevation dataset. The elevation data doesn't perfectly match the buildings. I want to "flatten" the elevation data so that ...
3
votes
2answers
1k views

How to change the value of an attribute using QgsFeature in PyQGIS?

I would like to update one attribute of a feature. However, I don't know to update it using the feature object. I have to use data provider to update it. layers = ...
4
votes
1answer
157 views

Why is vector data not saved permanently in QGIS?

I'm using QGIS 2.2.0. I add a vector to a vector layer and save the file. After I reopen the .qgs file, the new vector is not shown. (1) Click 'Toggle Editing' (2) Click 'Add Feature' and draw a ...
1
vote
1answer
72 views

Create a point C from point A in the direction of point B

I am very new to QGIS and GIS in general. I hope someone could help me figure this out. I have pairs of coordinates which signify the start and end of a transect line. I am trying to adjust the end ...
1
vote
1answer
252 views

QGIS Scripting problem updating contrast enhancements for raster layers using bandStatistics

Found this function to update statistics for a raster layer : rlayer.setContrastEnhancement(QgsContrastEnhancement.StretchToMinimumMaximum, ...
0
votes
1answer
53 views

QGIS documentation in French?

I am working on a plugin in qgis and i have to make a document from A to Z about that but on French . and I am looking now for some documentation of python,QT , pyqt4, and QGIS in French.
0
votes
1answer
99 views

Repaint the map after updating a feature in QGIS

I update a feature in a vector layer using the following Python code: layers = QgsMapLayerRegistry.instance().mapLayers() layer = layers.get('my_vector20140614125509945') fid = 1 attrs = { 0 : ...
0
votes
1answer
130 views

How to turn WKBtype integer into text for memory layer creation in QGIS

I'm creating a memory layer in QGis python and I need to match the geometry of the memory layer that I am building to the geometry of another layer. After some investigation it seems to me that, as ...
1
vote
1answer
201 views

Plugin of Multiple buffers in QGIS

I hope to create a plugin to do multiple buffers in QGIS. This is my script: """/*************************************************************************** izisse_test ...
2
votes
0answers
106 views

Selecting only parallel lines along a center line

Read through the previous post how to find close and parallel lines but still looking for a simpler solution. Found several ArcGIS forums post on the topic but no answers there either. It seems ...
0
votes
1answer
42 views

Searching for features

Sorry for the newbie question. I'm trying to determine if I'm in the right place. With free, open source tools and data, I would like to be able to find (electronically, not by hand) properties (in ...
1
vote
0answers
28 views

How to: create a table containing point values (continuous) within polygons (continuous) [duplicate]

First off, than you very much for all the wonderful resources - you have all helped a novice GIS-er navigate and overcome a steep learning curve. What I am interested in doing is outputting a table ...
0
votes
1answer
589 views

How to overlay a jpg onto a google earth image?

I have produced a model from an online engine , and it is in a google earth picture. I want to georeference the below picture and apply the boundaries here on my google earth image. I'm using QGIS2.2. ...
1
vote
1answer
492 views

How to automatically fill a lat/long in attribute table

I´m not experienced in using QGis. I need to plot the distribution os a plant species on a map. I have created a shapefile for the species plots (name of file is PLANT). The coordinate system of this ...
1
vote
1answer
220 views

netcdf daily data to monthly raster layers

I have a netcdf (.nc) file of 95GB which consisted of daily data for a 50 years period. I tried to process this with ArcGIS (Multidimension tools – MakeNetCDFRasterLayer command) and it was not ...
0
votes
0answers
55 views

What is the QGIS 2.2 print layout map extent CRS?

I have project in ESPG:4326 with 2 layers (both in 4326), and map print layout. I've chosen current extent for layout map. Map is centered and prints as I expect. Next, I access this object via ...
2
votes
1answer
229 views

Smoothly interpolating Polygons from set of coordinates?

I'm still quite new to QGIS and I'm using it to display and analyze my soil data. I have point information on the distribution of the soils in a specific area and I need to create a soil map from ...
2
votes
2answers
108 views

“CRS selector” dialog after running a script

I add an empty vector layer using the following script. layer = QgsVectorLayer('LineString', 'MyLayer' , 'memory') QgsMapLayerRegistry.instance().addMapLayers([layer]) After I run the script, ...
3
votes
1answer
174 views

Generating polygons with streets as borders using QGIS?

I have searched online for almost a week and can not find an answer to my issue. I need to generate polygons from street borders in a given city. I have downloaded data from openstreetmaps and ...