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

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2
votes
2answers
49 views

Split Vector Points/Polygons by Vector Grid and assign to relevant grid

I have 3 vector shapefiles (1: Point, 2: polygon, 3: vector grid) that I would like to combine so that the points and polygons are 'assigned' to the relevant grid cell within which they are contained, ...
1
vote
0answers
36 views

How to automate the QGIS Raster Interpolation Plugin using python console?

I have a rainfall data from 1961 to 2015 for each day of this years. I need to create a raster for each day with this configuration. Do you know how to automate this using this plugin and python?
4
votes
1answer
65 views

How to get r.drain to run in QGIS/GRASS?

I use the GRASS GIS extensions for QGIS (QGIS version 2.12.3 with GRASS 6.4) and I have a problem with the r.drain algorithm: I simply cannot make it work with a given starting point as a vector ...
3
votes
2answers
143 views

latitude/longitude to linestring or points

I have a gps file that I have converted to csv, I would like to convert a longitude/latitude to linestring if the next row have a diferent longitude/latitude (if the car mooved) and if not convert it ...
5
votes
1answer
90 views

Merging .asc files = “The command line is too long”

Having problems merging LiDAR .asc folder files to produce a single GeoTiff file. I have followed various instructions e.g. the 2 methods of selecting input files for merging .asc files using ...
1
vote
1answer
45 views

How to write a string based rule, e.g. If “Name” contains 'NRG'

I have created a field called 'Name' in QGIS and I wish to create a rule-based style for a gridded vector. The grids are either 'NEP1' or 'NEP1NRG' etc. with values to 5000+. I want a rule to colour ...
1
vote
0answers
31 views

How to iterate through attribute visibility with PyQGIS?

I have a point shapefile with a timestamp that I would like to turn off and turn back on 1 by 1 with a new element of the attribute table appearing every second
1
vote
1answer
65 views

What's the best linux distro for QGIS? [closed]

What is the best linux distro for using QGIS? By best I mean: Easy to install latest version with all plugins. Includes QGIS map server and instructions for getting it running. Is easily updated to ...
4
votes
1answer
71 views

What is XYR in QGIS?

I am familiar with XY, XYZ, and XYZM, features but I created a spatial layer in PostgreSQL and added it to my QGIS. When I opened the Vertex Editor it showed me values for XYR and I am not familiar ...
4
votes
2answers
74 views

SLD styling in QGIS, elsefilter not working

I need to figure out how to make elsefilter work when imported into QGIS (2.8.3) via sld. <?xml version="1.0" encoding="UTF-8"?> <StyledLayerDescriptor xmlns="http://www.opengis.net/sld" ...
1
vote
0answers
52 views

QGIS not showing attribute updates

I have a feeling I know the answer to this but want to make sure before I start redoing all the work. I've recently started using QGIS to help with mapping of an estate. Last week a created a new ...
4
votes
0answers
51 views

QGIS Profile Tool shows no profile

I have installed and followed the process to produce an elevation profile from the Route Profile plug-in in QGIS, but for some reason I am getting no profile to appear. The grids are from OS ...
2
votes
1answer
45 views

IPython plugin not loading in QGIS 2.12

I am trying to run the IPython console plugin in QGIS 2.12 After installing the plugin there is this error: You need to install IPython 3.1.0 (and then restart QGIS) before running this ...
5
votes
2answers
123 views

Upgrading from Qgis 2.4 to 2.12 on Ubuntu 15.04

This should be a simple question. On Ubuntu 15.04 how can I get Qgis upgraded from 2.4 to 2.12?
3
votes
1answer
46 views

in QGIS how to add (join?) another table to a layer

Very new so bear with me. I have QGIS loaded with a TIGER/Line Shapefile at the Block level for a County, and need to join other detailed CENSUS data various tables (which also have a Block ID to ...
1
vote
1answer
31 views

rendering a single band raster - new maxvalue

I have a downloaded raster file, singlebandgray, and want to redefine it's maximum value to a higher integer value. Via the QGIS desktop it works smoothly by hand via the Properties. Via Python I was ...
2
votes
0answers
35 views

How can I convert a shapefile from a single line segment to separate side segments using PostGIS?

I have a shapefile (STC) which is a single line segment per street with information for both the odd and even sides of the street. This .shp file has to be converted to separate side segments. To do ...
2
votes
1answer
39 views

Actions undertaken in QGIS somewhere stored as Python code in a history file?

For practioners that are not willing to study all the methods for each class, it would be helpful if every action that was made within the QGIS interface can be looked up afterwards in a history file ...
2
votes
0answers
51 views

How to Georeference in QGIS 2.12.1 Lyon

I used to be able to Georeference in QGIS but now I can't. These are the steps I go through. At the end of it nothing happens. No layer is added to my Layers Panel and no document is created in the ...
1
vote
0answers
36 views

Is there any official OSM WMTS service?

The Geospatial Information Authority of Japan (GSI) started to provide national tiled maps in 2012. Initially we could not use the tiled maps with GDAL TMS minidriver because the tile URL naming ...
1
vote
0answers
18 views

Sampling within an area and creating table Qgis [closed]

What I am wanting to do is import two point files, one harvest data, another soil sample results. Once I have them I want to create a buffer area around the sample point (75ft) and determine the ...
6
votes
2answers
157 views

How to speed up this script in QGIS?

I am a new in PyQGIS, I want to create a Point layer from a raster layer. In table of point layer created, there is 3 fields by name of "X_coord", "Y_coord" and "Azimuth", each point in Point layer ...
3
votes
1answer
32 views

How to combine 2 vector shapes created from raster files

In Qgis 2.12 Lyon, using windows 10 I downloaded 2 raster files from an area of my interest. The rasters were on information about precipitation and evapotranspiration. Each cell had a value. I ...
3
votes
0answers
56 views

Python script to automate saving satellite images for different combinations of lat longs

PS. : This is my first try at a GIS application. Please forgive if my question is pedantic. I would like to get a series of satellite images all at the same scale centered around different points on ...
1
vote
0answers
33 views

QGIS polygonize tool not working [closed]

I am having a problem using QGIS ver 2.10.1 Pisa. I am trying to use the polygonize function on a raster .tif image, and it runs, but only produces a thin sliver of polygons at the top, then stops ...
1
vote
0answers
34 views

Generating continuous aspect surfaces from DEM with QGIS

I'm trying to extract aspect surfaces from different DEM sources at different resolutions in QGIS. I've had success working with SRTM-derived grids (3-arcseconds) and am trying to perform the same ...
1
vote
0answers
56 views

Discovering highest point in area using QGIS?

I'll preface by saying I've never used or even heard of GIS software previously, so I'm sorry for being very clueless. My goal is to find the highest point in Highgate (in London, England). I have ...
2
votes
1answer
72 views

Image in wrong location in qgis2web

I'm using the qgis2web plugin to display a Landsat image and some agricultural fields. Both raster and vector data are in EPSG:4326. In the QGIS canvas, the vector and raster line up (left side of the ...
4
votes
0answers
36 views

Custom forms feature in QGIS: QMessageBox.warning closes QDialog as well

I am attempting to work with custom forms in QGIS. I have included a validate function in my code that will pop a QMessageBox() if the validation fails. My problem is that when I close the QMessageBox ...
9
votes
2answers
208 views

Make several rasters more uniform

I have imported some rasters that is supposed to be continuously connected but instead they create some sort of bordered grid between them. I may assume that this is a matter of calibration between ...
3
votes
0answers
29 views

How to fill composer map with canvas data and export composition as png using Python script in QGIS

I'd like to create a Python script in QGIS that will take some data (shp + tif, in my example), use tamplate Map Composer (from a file) and export created composition to a png image. With almost no ...
1
vote
1answer
52 views

Change NODATA values to 0 in Qgis

I know this question has been asked already in this forum, but I couldn't find an easy (for me, a rookie) solution for my problem. I have an RGB 3 band file which, in some pixels, has i.e. R no data ...
3
votes
2answers
81 views

How to know if your script is executed in a QGis python console or a standard python console?

Is there any way to detect if a script is computed on QGIS python console or not? Any attribute or test to assess it?
5
votes
2answers
107 views

Field Editor with Python: select by attribute & open table (QGIS)

I want to search on number values (>, = etc.) within a column and open table for the selected ones. It's an easy task within field calculator, but I want to see how it's build up with the python ...
2
votes
1answer
40 views

Data defined Style gives not same color in toc as on the canvas

QGIS 2.12.0 Lyon I have a object with following attributes: shape [QString] ...circle, square size [integer] ...8, 10 color [QString] With the widget value map i fill these fields according csv ...
1
vote
1answer
24 views

Load postgis database with PK from two fields in QGIS [closed]

I have a PostGIS database having a Primary Key from two fields id_cat and id_cdad. When I load this database in QGIS in my computer under Linux there are no problem. I unmark "Select ID" and I can ...
1
vote
1answer
43 views

Is it possible to send an OpenLayers map to QGIS for printing?

I have an existing OpenLayers/GeoServer/PostGIS/GeoExt project and I am looking for a way to print an OpenLayers map that contains WFS layers, vector layers dynamically created by users, and WMS ...
0
votes
1answer
39 views

how to debug mapserver / postgis returning 0 results? ( MapServer WMS 1.1.1 / Google Earth / QGis )

user30184 answered the same question here Why is mapserver returning a blank image? user30184 answers to start by specifying SRID and that it often has to do with extent and projection. I imported a ...
1
vote
2answers
36 views

XyTools QGIS plugin for attribute export

I want to export an attribute table to Excel. I see XyTools is used for that (is there another plugin?). Since I installed QGIS from OSGeo4W, I have the required library. However, when I tell XyTools ...
1
vote
2answers
52 views

How can I ensure the image exported from Print Composer is accurate?

I'm using QGIS version 2.12.2, and using print composer to export my map to an image file (I've tried pdf as well). In the print composer it displays fine - just a basemap overlayed with land type ...
5
votes
1answer
107 views

How to cartographically generalise buildings/settlements in QGIS?

I have a set of buildings in a polygon layer which I'm going to use in a 50k map. Since the buildings are tiny I cannot show the actual form of the building, instead I'm taking the centroid of the ...
1
vote
3answers
138 views

Geoprocessing Tools - I can't get Intersect/clip to work

I desperately need to intersect two layers, one of 32 large polygons (towns) the other of many smaller areas with those towns, so that I can classify and make calculations on the smaller areas sorted ...
0
votes
0answers
11 views

How to access components on UIFileLayout?

I have followed How to programmatically associate a layer with a custom UI? and added successfully my custom *.ui file to the editing window in QGIS. Now I would like to add an action to my custom ...
1
vote
0answers
27 views

Python QGIS - How to add the classic edit Menu in the Menu Bar

I am doing a QGIS application. Here is the plan: I start QGIS with no menus, toolbars, panels, etc. With nothing ! For that I have modify the QGISCUSTOMIZATION.ini With a plugin who start with QGIS ...
1
vote
2answers
48 views

I can't find geotag and import photos plugin (QGIS plugin)

I am doing a project on mapping tourist attractions and would like to attach photos and videos to point locations. I have read about the Geotag and Import Photos plugin but I can't find it in my ...
2
votes
1answer
26 views

Qgis 2.8 filtering the ten most populated places for a specified altitude

I try to filter data combining settlement and altitudes. I try to filter the 10 most populated places for a specified altitude. I tried this expression without success: "altitude">1000 AND ORDER ...
1
vote
1answer
23 views

capture mouse movement on QgsMapCanvas

I have a python app that uses QgsMapCanvas as map display. I put it inside a QWidget, which is then inside another control. The problem is that there seems to be no way of tracking mouse move event on ...
2
votes
1answer
165 views

Trojan in QGIS 2.12.3?

I have installed the latest QGIS, version 2.12.3. However, when I open it, Symantec says that it has discovered the trojan SONAR.TCP!gen4. See ...
1
vote
2answers
51 views

check the “quality” for (poly-)lines (density of vertices)

I want to check the quality of digitized tracks. I suppose, that a track with a lot of regular vertices has got a good quality. And a track with less regular vertices has got a poor quality. Maybe, ...
1
vote
0answers
26 views

Geocoding and SRID - can't get desired SRID

I want to geocode a set of addresses with GoogleMaps, store the results in a different SRID in a PostGIS table and then project it in QGIS over a layer with the identical SRID. So far, it has been a ...