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

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3
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1answer
54 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
32 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
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0answers
24 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
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0answers
18 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
55 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 ...
0
votes
0answers
74 views

Tree counting using LiDAR data

Does anyone have any ideas on tree counting using lidar point data? I have a small set of lidar point data (plantation area about 500 hectares), from which I want to collect number of trees per ...
2
votes
1answer
38 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
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0answers
15 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
15 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
35 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
34 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
25 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
13 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 ...
0
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0answers
31 views

Snapping points to polylines and maintaining minimum distances between the points as well as meeting other parameters

I have thousands of locations that I would like to snap to be placed on top of a hundreds of polylines based upon matching attribute fields. Think of them exit signs located on every ...
1
vote
0answers
24 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
37 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") ...
1
vote
0answers
9 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 ...
1
vote
0answers
32 views

How to show two layers at the same time in Qgis

I have a question about Qgis layers. I want to see two layers at the same times. one is lines which are boundary lines and the other is polygon which are district. when i was surfing about this ...
1
vote
1answer
36 views

Is it possible to import .ecw images into QGIS 2.10 for UBUNTU?

We want to import .ecw images. We have done it using QGIS 2.8 for Windows in the past, but we can't using QGIS 2.10 for UBUNTU. Thanks.
2
votes
2answers
88 views

Problem with PostgreSQL View layer in QGIS

I have a PostgreSQL table and view: CREATE TABLE lines ( geom geometry(MultiLineString,4326), type character varying(254), login text, gid serial NOT NULL, ...
1
vote
0answers
12 views

How to SetVisible a layer without redraw all the mapcanvas

I am working with QGis 2.8.2 API c++/ QT 4.5 I am displaying a lot of layer in a mapcanvas, I am looking for a method like setVisible(boolean ) in order to setvisible or not a specify layer ...
4
votes
5answers
138 views

GPS Track Editor to crop tracks with select by clicking start and end points

I'm trying to take a bunch of gps tracks of mountain bike rides and turn this in to a trail map. I want a single track for each trail. I'm looking for an editor that will allow me to select a ...
1
vote
0answers
40 views

CSV file locked for editing after join

I have created a table join between a vector shape-file and a csv file using pyQgs. Now i want to edit the csv file (not from inside QGIS) . But when i double click on the csv file , it says that ...
2
votes
1answer
33 views

How to calculate the form (or shape) factor of a polygon?

I am using QGIS to calculate the form (or shape) factor of polygons following what Louf and Barthelemy did here: http://rsif.royalsocietypublishing.org/content/11/101/20140924 The form factor is ...
1
vote
1answer
35 views

QGIS export attribute table to csv and keep value relation

If i export my joined table to csv i get the numeric id value instead of the value relation name from the joined table. Can I export my table with the value relation value? Best regards
1
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0answers
34 views

Calculating minimum distance using “Distance Matrix” in QGIS

First of all, I'm very rookie in using QGIS. I want to calculate minimum distance between points and a line in QGIS. I use "Distance Matrix", point shape file contains 1337 points data, and I made ...
2
votes
1answer
61 views

How to add loading bar in QGIS Plugin development?

Every time i use tool or plugin in QuantumGIS, i saw a kind of bar like this for indicating loading progress : The different between that bar and Progress Bar is that progress bar will increase ...
1
vote
0answers
33 views

Projecting a world map on 6 segments to print on ball

Working with QGis and data from Natural Earth I would like to prepare a world map (1:50 000) for a globe that can be printed in 6 segments, which glued together build a ‘sphere’ (ball) according to ...
1
vote
2answers
68 views

Python and QGIS multiprocessing documentation?

Where can we find better documention for python QGIS multiprocessing. Especially regarding the multiprocessing of python and QGIS.
0
votes
0answers
30 views

Postgis ST_Azimuth only returning a small range of angles

I have a puzzler with postgis and ST_Azimuth. I have a table of points (taken from country borders, and run through the QChainage plugin). I want to find the azimuth from a fixed point (15.0,50.0) to ...
1
vote
0answers
43 views

Print/Export Attribute Table in Form View (QGIS 2.10.1)

Is there a means or available plugin which works to enable a direct print of the attribute table in form view? I recall this feature was on many a wishlist back around 2.6, but I'm unaware if the ...
0
votes
1answer
42 views

QGIS Vector Data with blank attribute tables

I have vector data shapefiles for Manitoba, but there is no names in the attribute tables. It seems Manitoba is still working on their attribute data. Is there a shapefile I can download to get these ...
1
vote
1answer
25 views

QGIS - Level curves - Voronoi Polygons

I am facing a difficulty in QGIS (2.8.2): I have three layers: layer 1: layer with points layer 2: layer of level curves (contour lines) layer 3: layer of Voronoi polygons obtained from the points ...
3
votes
1answer
49 views

Standard user interface for QGIS plugins

QGIS plugins found in "processing" all have the same user interface. In particular, to open a file, the selector either show the list of already downloaded files, or have a "..." button to browse and ...
1
vote
0answers
31 views

Opening shapefile and Tiff layer Coordinates do not match up

I am new to using QGIS and am having a major problem. I have the UK Ordnance Survey (OS) 1:25000 raster layer in Tiff format open. When I open a shapefile or mapinfo vector layer on top of it the ...
1
vote
1answer
40 views

I am using “Hindi and Gujrati” font then I am getting “Black Squre Dots”?

At the time of generating PDF file when I am using “Hindi and Gujrati” font then I am getting “Black Squre Dots”. Below I am using code. Here I am trying to convert in UTF-8 but it’s not converting. ...
2
votes
1answer
148 views

Same Raster but different min/max in ArcMAP and QGIS

since I am abandoning windows to stay only with Linux, I started learning how to use QGIS. So far so good. However, trying to reproduce a python script from Arcpy to PyQGIS I noticed something. When I ...
10
votes
5answers
180 views

Fisheye-like projection

I need a special projection for the purpose of effective presentation on a poster. I'd like to present the study area (Czech republic) in a context of whole Europe in such a way, that the Czech ...
0
votes
1answer
59 views

How to connect QGIS to PostGIS? [duplicate]

I want to establish connexion QGIS and PostGIS in order to run the pgRouting Layer, how can I do it?
1
vote
1answer
24 views

Convert Shapefiles into Raster — C++

I'm coding an algorithm which uses as an input a map from QGIS. The software has been implemented in C++ and my idea is to convert, automatically, a shapefile into a raster one. Is there any function ...
1
vote
0answers
37 views

What could be making QGIS 2.10 crash when loading a project file?

On QGIS 2.10, running on Ubuntu 15.04 Linux, I have a project file that has a fairly large number of mainly shapefile layers, which gets to 99% on the slider to the right of where it has a message ...
1
vote
0answers
28 views

Suggestions of route optimization algortihms to implement on QGIS

I need to compute routes on a QGIS project with time and distance associated. Is there any route optimization algorithm to compute routes given the points that one want to connect?
1
vote
0answers
29 views

QGIS 2.10.1 : Function editor tab indents generating errors …?

i'm trying the function editor in QGIS 2.10.1 (windows 32 bits). I always get "indents" error as the function editor inserts TAB indents instead of spaces ... How do i solve this issue ? Thanks ...
0
votes
0answers
26 views

QGIS Spatialite tabular updates are very slow

I am exploring Spatialite in QGIS (2.10.1), and it is very slow to save tabular edits (with 1200 records, several minutes once I click the pencil button, versus less than 1 second with the data as a ...
0
votes
0answers
22 views

Can we integrate QGis with Java? [duplicate]

Inegrateion of java with Qgis and its extensions? In case, If integration is possible can we use multi-threading qgis and java?
4
votes
2answers
158 views

How to correctly install QGIS 2.8.3 with GRASS plugin on Ubuntu 14.04?

I already tried to install QGIS 2.8.3 using the procedure described on: http://www.qgis.org/en/site/forusers/alldownloads.html#debian-ubunt, but grass-plugin do not compare on plugin list! I tried ...
1
vote
0answers
38 views

QGIS open tif file larger than 10 GB, '*.tif is not a supported raster data source'

When trying to use QGIS to open a tif file larger than 10GB, I encountered an error says "*.tif is not a supported raster data source." Is there any way or other software to open large tif files?
1
vote
0answers
20 views

QPyNullVariant when working with csv

id = 5 expr = QgsExpression("ID ="+str(id)) selected = csv_layer.getFeatures(QgsFeaturesRequest(expr)) features_list = [feature.attributes() for feature in selected] print ...
1
vote
0answers
54 views

How to integrate QT User Interface with QGIS Python Plugin?

I created a very simple python program using GDAL to calculate the summary and reduction between two raster value like this : import os from osgeo import ogr, gdal from gdalconst import * ...
1
vote
1answer
36 views

QGIS label spacing

Wondering how to space out the road names on my QGIS map to make it look cleaner?