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

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2
votes
0answers
80 views

Using Terrain Profile plugin with an interpolated raster

I am very new to QGIS and the goal of this exercise is to view an elevation profile of a river from a set of discrete points taken from surveying records. Steps taken: A vector layer was created ...
2
votes
0answers
49 views

Prevent polygon feature (catchment) overlap for land-use extraction using QGIS?

My aim is to calculate catchments for around 150 points and to extract land-use variables for them. In order to do so I need a vector dataset where no polygons overlap. This, however, seems to be a ...
2
votes
3answers
120 views

How to find the extent of (many) EPSG CRSes?

I want to map the geographic extents / bounding boxes of a lot of EPSG CRSes. At least, those with a rectangular geographic extent. For example, take epsg:2004, visiting that page shows the extent (...
2
votes
1answer
795 views

How to group points in QGIS?

I need to group 400 points in 10 groups with 40 points each. The goal is to get the 40 points geographicly together like this: Any idea how to do this with Qgis Pisa?
0
votes
2answers
161 views

How to save layer as dbf using pyQGIS?

Is it possible to save layer as dbf? Or even better convert .csv to .dbf? I have some .csv files, no geometry just attributes and I need it as .dbf as I want to edit them (I found that Qgis doesn't ...
2
votes
2answers
331 views

Project file read error: Unexpected end of file at line 9957 column 1

On reading the answers from a similar question earlier i still cannot retrieve my project. I last used this project in June and obviously something went wrong when saving or creating the new layer ...
1
vote
1answer
61 views

How to add a point in a empty vetorLayer creadted in memory

I am working in c++/qt 4.5 and qgis api c++ 2.8.2 I had to create and empty vectorLayer and add Point I saw in the qgis cookbook that it is possible to create a vector layer in memory ,I did that, and ...
1
vote
0answers
31 views

Clip Categorized Polygon with another Polygon

Ok, so first off, I've gone through the forum, and looked at every post that sounds similar. They have all been solved, but none of the solutions have worked for me. Basically, I have created a ...
1
vote
1answer
89 views

Qtiles won't work with Range Scale?

I am using QGIS with QTiles plugins. It was working perfectly, until I use Scale Range within my style. When I do so, the Scaled Range layer is not printed at all on the generated png. Do you know ...
1
vote
0answers
90 views

How to load and execute python scripts from a local path after python console is triggered in QGIS?

I had created a file named "startup.py" in users python home directory (... .qgis2/python) and i had triggered the python console in startup.py file by import qgis qgis.utils.iface....
0
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0answers
16 views

Problem in export as a imagefeat in QGIS print composer [duplicate]

I am trying to overlay the sluice map with background of google satellite. Everything working fine when I do it in Print composer. But when I export as a image, the whole map gets shifted and it is ...
0
votes
1answer
67 views

How to use SpatialOperator in filter expression in QGIS

In a python script I want to specify a request filter expression using a spatial operator. I am following the general syntax "field name" operator condition. For example: setFilterExpression('$...
1
vote
0answers
15 views

How can I check If Features do not have an SRID set or are similarly malformed? [duplicate]

QGIS does not display all Features of Layer and behaves weird instead I got the comment: "How did you create the other features in PostGIS (as opposed to the ones that were edited)? My initial ...
1
vote
1answer
53 views

Why is the heatmap color not showing in TileMill?

I created a heatmap on QGIS (2.8) and styled it using singleband pseudocolor. I want to turn it into map tiles, so I added the TIFF as a layer in TileMill. However, when it's in TileMill, it loses ...
1
vote
1answer
213 views

QGIS corrupting shapefiles?

I'm hoping someone out there might be able to help or suggest some tests to try and resolve some very odd QGIS behaviour of late... Our core GIS team of 4 users has been testing v2.10 prior to roll-...
1
vote
1answer
415 views

Autocad DXF to Qgis and exporting to KML for viewing in Google Maps

/ Background: I have a DWG trace made in AutoCad using Gauss-Kruger coordinate system ( a CRS used in Slovenia ). I'm using AutoDesk Map 3D to transform the coordinate system to WGS84.PseudoMercator ...
1
vote
0answers
86 views

Use cython in QGIS?

I've wondered for some time how to use Cython in QGIS. I know I can integrate a Cython code in python, but I want Cython to handle QGIS classes. QGIS is built upon QT, every qgis object is a qobject ...
-1
votes
1answer
71 views

Marker line in CartoCSS

I'm trying to symbolize a line layer in CartoDB using CartoCSS. I need my line to be a series of diagonal lines, something like this -> ///////////// In QGIS I would do this as a marker line with a ...
0
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0answers
68 views

Error's while retrieving data from postgres to Qgis using python?

This is my code of python in qgis from qgis documentation docs uri = QgsDataSourceURI() uri.setConnection("localhost","5432","gis_data","postgres","vajja") uri.setDataSource("","poi_sv1","long","","...
3
votes
1answer
283 views

QGIS 2.10 with ubuntugis dependecies Grass issues Ubuntu 14.04

I saw in How to correctly install QGIS 2.8.3 with GRASS plugin on Ubuntu 14.04? how to get Qgis 2.10 running from the non ubuntugis repository with grass features but I'm still having problems with ...
1
vote
1answer
34 views

Creating a new layer from a spreadsheet and an existing shape file in QGIS

I have a map of US zip codes and a spreadsheet that associates data with specific zip codes. I want to show the zip codes where the most data exists using a gradient, but I am not even sure how to get ...
0
votes
0answers
49 views

GIS route creation from street names

I have a list of streets comprising 300+ routes. Each route (in text) lists 4-5 street names where the route should take place. I would like to create each route, that is, plot the street names and ...
1
vote
2answers
73 views

Combining several mask rasters to obtain one single mask with binary values

I have a series of separate rasters which represent the cloud cover over the same area but in different months. Each raster has 2 values: nan for "no cloud" and 255 for "cloud". What i want to do is ...
1
vote
1answer
84 views

PostGIS Query returns duplicated rows

I'm trying to create a shape file of a state. I have a map of US zipcodes that I downloaded from the US Census and I want do create a shapefile of zipcodes in Florida. I ran this query which ...
2
votes
1answer
186 views

Cartogram not working: “Cancelled by user” - Why?

I am using the QGIS Cartogram plugin, but unfortunately something is not working as it should. First, the demo works just fine. But when I want to create a cartogram with my own layer. But as soon ...
1
vote
1answer
265 views

QGIS 2.10.1-Pisa [duplicate]

Since the version QGIS 2.8, each time I start to open it it begin wth this error message. I have Mac OS X 10.7.5 MacBook Pro, late 2011. It works but what do it means, and what should I do, I install ...
2
votes
1answer
173 views

Is it possible to open WMC(Web map Context) file in QGIS?

I am new to WMC and in our application we had a requirement to extend the WMC functions. For that I need to know whether QGIS have the support of WMC files. Or we need any plugins for WMC support ...
2
votes
0answers
228 views

Qgis delimited text layer from an excel file converted to .csv

I'm trying to add a delimited text layer using coordinates. The file has been created in excel and then converted to a csv file in the saving. When I put it into Qgis it doesn't recognise the headings-...
3
votes
2answers
435 views

Join and export .csv file as .shp in QGIS?

Here's what I'm trying to achieve: Load the required GIS layer (*.shp file) Load the .csv file in QGIS Perform the join based on common attributes in the two files Export the mapped .csv file as a ....
0
votes
1answer
24 views

Error while displaying qgis project via qgis2leaf plugin?

couldn't see the map on the browser while using QGIS2LEAF Plugin in QGIS 2.10 Pisa. It gives error on web page saying: error at line 8: L is undefined. Please let me know if anyone knows the ...
1
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0answers
37 views

Is it possible to interact with a running instance of QGIS from the command line?

I just started looking at QGIS on MacOSX. I installed the MacPorts package and found the executable: /Applications/MacPorts/QGIS.app/Contents/MacOS/QGIS* Unfortunately it appears that the command ...
1
vote
1answer
152 views

pixel values beyond valid range in QGIS

I opened a sub-dataset of an HDF file (NDVI layer of MODIS HDF file) in QGIS, but pixel values are beyond the valid range (-2000,10000). I see many pixels way less than -2000 and way over than 10000. ...
2
votes
1answer
85 views

Difference between qgis.utils and qgis.core?

Please, can you tell me what is the difference between qgis.utils and qgis.core ? I'd like to understand step by step the QGIS API Document.
0
votes
1answer
74 views

Error while connecting qgis with postgres?

sql="select long,lat from poidata.poi_ca from where city LIKE '%unnyvale'" uri = QgsDataSourceURI() uri.setConnection("localhost","5432","gis_data","postgres","vajja") uri.setDataSource("",sql,"long","...
2
votes
0answers
96 views

QGIS does not display all Features of Layer and behaves weird instead

I have a weird problem with QGIS trying to load a Layer from a Postgis Database When I open the Layer from Postsgis I have two choices: Method one: Either, I use the Panel "Browser", where I can ...
3
votes
1answer
90 views

Need to include GPS data in a GIS system

I work for a small telematics company and we received a request from one of our clients about integrating their vehicle GPS locations to their ArcGIS system. Our current system simply displays this ...
1
vote
1answer
57 views

CategoryList attribute for predefined color ramp in pyQgs

I am trying to style my vector layer in QGIS using the following python code: layer = iface.activeLayer() myStyle = QgsStyleV2().defaultStyle() defaultColorRampNames = myStyle.colorRampNames() ramp = ...
1
vote
0answers
41 views

Creating Origin Destination Matrix from Station Locations

I am attempting to create an origin destination matrix in python for all of the London Underground Stations. I have the station name and the lat, lng of its location. It is in the following csv format ...
1
vote
0answers
54 views

Export Feature with attribute to dxf

I'm trying to export features with at least one attribute to dxf, is that possible? E.g. I need the name or layer name of the feature in the CAD application.
1
vote
1answer
111 views

Presentation of terrain and sub-terrain data in 3D using Qgis

I have DEM of karst and .shp files of caves in that area exported from "speleoGIS" Therion http://therion.speleo.sk/ Qgis2threejs is amazing in making visualisation of 3D sourface, which is easy to ...
2
votes
1answer
224 views

Show Log of the Sql statements that QGIS generates to retrieve Data from Postgis

Is there a ways to - make QGis log its generated SQL Statement or to - force POSTGIS to log all interaction with QGIS? There is something strange happening to the WFS layer I retrieve in QGIS, since ...
1
vote
0answers
36 views

Rendering problem in qgis

I have fetch data from database and draw it on qgis 2.8 as vector layer it works fine with limited data but for large data it will not work and goes into not responding stage, I am unable to ...
1
vote
1answer
52 views

QGIS Relations loss of form style

I'm currently creating a project for management of highway drains in QGIS which involves the recording the feature attributes and logging of multiple inspections against a feature. I have a layer for ...
1
vote
1answer
52 views

What data format to do temporary editing with QGIS before committing it to a RDBMS?

I am trying to create a temporary spatial data from a PostGIS database that a user can do the editing on. Currently, I have a service that returns GeoJSON from the PostGIS database. But I don't think ...
1
vote
1answer
363 views

Rule based labels using QGIS?

I couldn't find an option of "rule-based"-labeling in QGIS 2.10. For example that big cities are also labeled bigger than smaller cities. Am i missing something or doesn't it exist?
1
vote
0answers
82 views

Inputting Longitude and Latitude in CSV from Geotagged, Photo Coordinates (WGS 84)

I am trying to take Geotagged picture coordinates and put them into a CSV file to display in QGIS as point values. Using Picasa, I can see that the picture coordinates are in the correct locations on ...
0
votes
0answers
27 views

Is it possible to set up the atlas coverage layer to automatically clip other layers contained in the project?

Lets say I have two layers, one with county limits and another with roads for that same area. I'm trying to set up an atlas with counties as the coverage layer, so that I get a set of maps, one for ...
1
vote
0answers
52 views

How to write a loop selection by location and export in QGIS?

I would like to be able to make selections in sequence between buffers and surrounding areas. This would lead to areas (polygons) being selected repeatedly by 2 or more buffers and I want to be able ...
2
votes
1answer
45 views

I tried to run QGIS using python but I couldn't get any output on screen?

uri ="C:/Users/rajagopalv/Desktop/poi_sunnyvale.csvdelimiter=%s&xField=%s&yField=%s" % ("|", "x", "y") vlayer = QgsVectorLayer(uri, "address_sunny", "delimitedtext") QgsMapLayerRegistry....
1
vote
0answers
10 views

QGiS 2.8.2 Graduated style symbology [duplicate]

I'm having trouble inQGIS with the symbology. I can classifify and categorized my data. But i cannot with the graduated symbology? I've try different format in Excel. And i cant find the problem ...