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

learn more… | top users | synonyms

0
votes
0answers
4 views

How to quickly add a DWG with multiple layers?

In QGIS 2.14 "Essen", I need to add a DWG with multiple layers. So I choose "add vector layer" feature in QGIS 2.0 to import the .dwg/.dxf file. However, QGIS adds all layers from the DWG file ...
0
votes
0answers
19 views

GDAL Raster plugin doesn't work

I am connected to Oracle, using QGIS and can see the vector data table. I am trying to use the GDAL Raster plugin to view raster data, in QGIS. When I click on the Oracle GeoRaster plugin, get a ...
2
votes
1answer
22 views

QGIS 2.14.4 attribute table fields not visible in Statist plugin

I had one point shapefile to which I joined new numerical attributes by a csv text file. I saved it by right clicking and everything works fine, I use it for calculations etc. But when I use the "...
0
votes
0answers
10 views

Grid Reference autotext expression

I am trying to create some extremely user friendly print composer templates that have an awful lot of autotext data that updates for each composer without having to manually type it in. I ave done ...
1
vote
1answer
46 views

how to join a road network into as few lines as possible?

I am processing a polyline file that contains multiple lines representing city roads. I would like to join the lines together into as few lines as possible. I've tried using the 'join multiple lines' ...
0
votes
0answers
8 views

How to add legend to rasterlayer in Qgis2Web plugin while exporting maps?

Is it possible to add a legend for Rasterlayer directly from the Qgis2Web Plugin or do I need to add the code manually?
4
votes
0answers
37 views
+50

Problem executing vectorgrid (from processing) in a standalone script using QGIS 2.8.6

I have the following piece of code which I execute within QGIS 2.8.6 import processing import ogr restrLayer = QgsVectorLayer("/home/usr/Desktop/trial/EligibleAreas_polygons_filtered.shp", "...
2
votes
1answer
106 views

Finding list of all shapefiles that overlap with single shapefile using QGIS?

I have a list of 34 shapefiles. These shapefiles are range maps for different species. I would like to take 4 of these shapefiles and document a list of those shapefiles (within the 30 shapefiles), ...
2
votes
1answer
36 views

QGIS vector clip extremely slow?

I'm trying to clip a large polygon shapefile (nearly 440,000 features, 0.5GB) to a shapefile containing a single polygon. Both shapefiles use the same CRS (EPSG:27700). With QGIS, using Vector > ...
1
vote
2answers
52 views

Add attributes to layer

I'm trying to add a new attribute to a vector layer in my plugin. But it does not work.. Why? selectedLayerIndex = self.dlg.comboBox.currentIndex() selectedLayer = layers[selectedLayerIndex] name = "...
2
votes
1answer
27 views

Re-import custom functions without restarting QGIS

I have a python file (in [user]\.qgis2\python) with some functions that I'm working on. It's just a .py file with a bunch of def function_1, def function_2 etc. in it. On startup I import the .py file ...
1
vote
2answers
28 views

Setting up rulebased labelling programmatically in QGIS?

In my plugin I do some labelling a vector layer with QgsPalLayerSettings. This works fine for me with QgsMapRenderer::setLabelingEngine. But now I also want to implement the rulebased labelling. In ...
0
votes
0answers
12 views

QGIS - moving projects (server to local hard disk or removable drive)

I have a QGIS project on a desktop that I need to move to a laptop to take into the field. Whilst in the office, both PCs talk to the project on server via a persistent mapped drive (L:) - ie. ...
0
votes
0answers
12 views

Getting HTML webpage into QGIS layers panel

I have created a webpage that capture information from heremaps and write to DB using Heremaps API and PHP. How do i run this webpage into QGIS like other WMS or WFS and do the same mechanism which it ...
1
vote
0answers
16 views

QGIS - Loading custom functions automatically

Is there a way to have custom functions automatically load in QGIS on start up? I've got a custom function for the print composer that prints out copyrights, but every time I start QGIS up and go to ...
1
vote
0answers
15 views

Add attribute column with road's altitude

I have some vector layers with a set of latitude and longitude coordinates.Is it possible to add a new column to the attributes table containing the altitudes of the road? (the data was collected ...
0
votes
2answers
46 views

Calculate distance between two points with QGIS 2.14.0

I need your help. I don’t use QGIS that much, so I’m a little bit lost. I have two shapefiles with the following information: List A: ID 1, xA, yA, ID 2, …. List B: ID 1, xB, yB, ID 2, …. x/y ...
1
vote
0answers
15 views

Three dimensional Routing

I have created a route by hand using the Tracing Tool available in QGIS. I wanted to export all the coordinates to another program, so I saved them in a CSV file. The problem is that I can only see ...
1
vote
2answers
36 views

Import shapefiles from Manifold to Qgis

is it possible to import a shapefiles from manifold to Qgis with the same projection.?
0
votes
0answers
8 views

QGIS Atlas turning on/off raster layers

I'm attempting to create a series of maps in qgis atlas with the same coverage and background data but different raster outputs (flood mapping outputs for a range of scenarios). I've created a .shp ...
2
votes
1answer
57 views

Clipping of a Raster changes Range of Cell Values

I'm facing a strange problem. I created a mosaic of two landsat scenes which contains values from ~ -5 to ~11 (Biomass estimation). As my study area is much smaller then the mosaiced Landsat8 scenes, ...
0
votes
0answers
29 views

Corrupted Shapefiles when saving edits in QGIS

Has anyone experience regular corruption of Shapefiles when saving edits in QGIS? Since testing the new LTR, we have had regular occurrences of the Shapefile being corrupted, and "_packed" SHP and ...
1
vote
1answer
25 views

QGIS: “Data source is invalid” error when calling method

QGIS 2.14 on Windows 7. I'm trying to call a method in a python script from the QGIS python console. I've put the directory in which the scripts resides in the PYTHONPATH in both the windows system ...
0
votes
0answers
13 views

Install unstable Qgis-master alongside release version [duplicate]

Good day I have the release version of Qgis (2.16) installed into Mint and it can be updated just with apt install qgis whenever a notification comes out that a new version is released. I want to ...
1
vote
2answers
289 views

How to compile QGIS from source with Grass?

I recently decided to reinstall QGIS and build against the latest version of GDAL - something I have been putting off for ages because I suspected it would be a nightmare. Lo and behold it has been, ...
5
votes
4answers
1k views

How do I rename Shapefiles in QGIS?

I have a huge list of layers in a project that are named in a foreign language. I want to translate and add the English title to the name. When I right click on a layer and choose Properties -> ...
2
votes
2answers
16 views

Correct syntax for loading virtualxl spatialite table?

I believe I have successfully loaded a virtual Excel table into a spatialite database using the SQL below - typed into the qspatialite plugin for QGIS. create VIRTUAL TABLE MyVirtualTable1 USING ...
0
votes
1answer
14 views

Direct access to DGPS data in QGIS?

I'm heading out to the Arctic Circle (Spitsbergen) I have a Sokkia DGPS and Magnet on a tablet device (connects to the DGPS and logs the data), they connect via blue tooth etc. Can I bring the data ...
3
votes
1answer
197 views

Is it possible to create tiles with transparent background using Qtiles?

I had created the tiles from shapefile using qtiles plugin in QGIS and that shapefile layer is a label layer created using MMQGIS plugin. But the thing is I want that tiles with transparent background....
1
vote
1answer
32 views

Why is the legend symbol alignment in Print Composer worse than in the main window layer list?

I created a point layer where point-symbols' size depends on a column of the attribute table. When they appear in Layers Panel, symbols look like this (every circle's centroid has the same "X-value" ...
2
votes
1answer
140 views

QGIS crashing/failing when dissolving multiple shapefiles in a Python loop

I am using QGIS 2.10 (but I've also tried 2.8) to loop through all the shapefiles in a folder (those ending in .shp) and perform a dissolve function on each of them. However, when I run the following ...
1
vote
1answer
65 views

Extract height values from vector to CSV

I have generated a CSV file (using the MMQGIS plugin) expecting to obtain all the coordinates of a vector layer that I have created. But the output file only contains the latitude and longitude ...
1
vote
1answer
26 views

Can't normalize LiDAR point cloud with lasheight and -replace z (LAStools)

When I try to use lasheight with -replace z to normalize the point cloud, the height of points are changed (destroyed heights; see pictures below). Without using -replace z everything is ok, but the ...
2
votes
1answer
222 views

Trouble Converting from a shp. to gpx file and up loading to GPS

Currently I have a series of random points within a shapefile that I would like to upload to my GPS. Every time I try to upload the points via "Save file" it come up with an error message (posted ...
-1
votes
0answers
20 views

Join attributes by location - QGIS

I am trying to perform an attributes join by location between a shapefile (with points) and a second shapefile (with polygons). The points are hydrometric gauges, whereas the polygons are catchments. ...
3
votes
2answers
1k views

How to connect a PyQGIS plugin with Postgres?

I have some questions for you: I created a python-plugin in QGIS, then I created a Qt gui fom my plugin and at last I created a Postgres DB now I need to make a connection between Qt-gui and ...
2
votes
1answer
26 views

Why does my reprojected globe visualisation not draw?

I have followed all of the instructions in QGIS Map Design, Graser and Peterson, Locate Press 2016, and cannot get the visual of the reprojected shapefiles clipped to Rome coordinates to draw as in ...
3
votes
2answers
285 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 ...
1
vote
1answer
19 views

QGIS: SAGA-GIS module “Add raster value to point” Error: unknown option 'INTERPOL'

I encountered an error while using the "Add raster value to point" SAGA-GIS module in QGIS (2.16) to retrieve altitude values from a raster DEM previously interpolated from TIN points (as vector ...
2
votes
0answers
35 views

QGIS GRASS: Error when converting vector to raster

I am trying to convert a vectorial layer (a grid of regular points with values, representing probabilities, associated to each point). I tried to use QGIS, but I got this error: ERROR 1: Attempt to ...
0
votes
1answer
22 views

Furthest point from polygon/point

I want to calculate distance between smaller dots (they represent towns, villages etc.) and these larger red dots (capital cities of admin. region). My goal is to show wich location is the furthest ...
11
votes
1answer
327 views

PyQGIS save raster as rendered image, then use GDAL tools on it

I have tried to use the code from QGis Save Raster as Rendered Image. i is a raster layer: pipelayer = i pipeextent = pipelayer.extent() pipewidth, pipeheight = (pipelayer.width(), ...
0
votes
0answers
25 views

Amending existing plugins to match Qgis 2.16+ fTools removal

Part-time development started about a year ago to create an add-on for Qgis. Many of this plugins capabilities are written with fTools commands. I am wondering if there is a recommended document to ...
4
votes
0answers
45 views

How to show labels exactly around a circle in QGIS?

I found an interesting way of proportional symbol mapping and labeling, I think this was made by Adobe Illustrator but I couldn't find out if it can be done in QGIS. What I am interested in the most ...
3
votes
2answers
77 views

How to organise complex styling rules in QGIS?

For example, my "roads" vector layer has the following attributes: road type: primary, secondary, local, track, or path surface: sealed, or unsealed segment type: road, bridge, tunnel, floodway, ...
3
votes
1answer
57 views

Why are QGIS field calculator statements (both IF and CASE) giving strange results?

Using the field calculator, I'm trying to update an attribute only if it equals to zero: CASE WHEN "Z" = 0 THEN "Z" = rand(1,100) END This let the 0 values as they are and updates all others to "...
5
votes
1answer
68 views

What does the “trusted” flag mean for QGIS plugins?

Can anyone provide some insight into the meaning of the "trusted" flag (true/false) that is listed on the QGIS plugin website when viewed here - http://plugins.qgis.org/plugins/plugins.xml?qgis=2.14 ...
6
votes
3answers
2k views

How to enable multithreaded processing in QGIS?

I have found multiple links that appear to say that this now exists in QGIS 2.2, but it appears that it's only using one core to full capacity. This is running on Ubuntu 14.04 The current process is ...
1
vote
1answer
74 views

Is QGIS multi-threaded?

Is QGIS (2.16) multi-threaded? I do not see multiple processes on the console while running it on Ubuntu. It only uses one CPU. Is there anything to do to enable it?
0
votes
2answers
27 views

How to filter features based on scale?

Shape file has visibility attribute. This attribute is generated by algorithm and there is a manual override. In QGIS, is there a way to apply global (per project) or local (per layer) filtering to ...