Episode #125 of the Stack Overflow podcast is here. We talk Tilde Club and mechanical keyboards. Listen now

Questions tagged [qgis]

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

Filter by
Sorted by
Tagged with
1
vote
1answer
328 views

Unable to edit PostGIS DB using QGIS 2.10, works on 2.8

I have data in PostGIS DB which I need to edit with QGIS. I created a project file with QGIS 2.10. I was able to connect and open the PostGIS database, but ran into problems when I tried to edit DB ...
1
vote
0answers
441 views

How to cut a raster with a polygon, but I'm interested in what remains after cutting?

I am using QGIS 2.14. What I have: A raster file and a polygon. What I need to do: Cut the raster using the polygon. Important: But I want to keep the remaining part of the raster from which the ...
1
vote
0answers
193 views

Why does QGIS 2.16 have longer load times than 2.8, especially working with tables?

I was previously running an LTR version of QGIS (2.8.9 I think). I installed 2.16 and found that opening tables takes a very long time. Deleting columns in tables now takes hours as opposed to seconds....
1
vote
1answer
429 views

Create GRASS Mapset in QGIS 2.12

How do you create a new GRASS mapset in QGIS 2.12? The GRASS panel has only the Open GRASS Tools button.I don't see any way to actually create a GRASS mapset in QGIS.
1
vote
1answer
6k views

Label features on hover/click with QGIS?

Simple question: Is there a built in/easy way to show labels for features based on a hover or click action with QGIS 2.0.1?
1
vote
2answers
159 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, I ...
1
vote
3answers
534 views

Fixing artifacts in rendered ocean polygons

I am trying to build a base map for North America with political boundaries, lakes&rivers, ecoregions, and oceans in QGIS. I can retrieve shapefiles from opensource websites that provide the data ...
1
vote
1answer
136 views

My Coordinate Reference System listing is in the wrong language

I just installed QGIS Desktop 2.0.1 on a desktop (Windows 8-64). All the menus are in English-US (as they should be), but the CRS listings -- when I try to change them for a project are a layer -- ...
1
vote
2answers
628 views

Centroids in QGIS 3.0 not using Python? [duplicate]

How do you calculate centroids in QGIS 3.0? In previous versions, there was an easily accessible tool in the vector geometry toolbar, but it is gone. I've seen ways to do it with Python on Stack ...
1
vote
1answer
268 views

QGIS batch affine transformations

I have multiple polygon and line shapefiles on which I would like to apply a translation so I was wondering if it is possible to batch process them (maybe with graphic modeler ?) or do I have to ...
1
vote
1answer
2k views

How to add legend in Qgis2Web plugin while exporting maps?

currently i am working with the publishing web maps with the Qgis2web plugin. but i didn't find any kind of legend window or event to add legend. Is there any other source to add Legend?below is ...
1
vote
1answer
132 views

Why does joining all layers in a group not work?

I am attempting to re-join all layers within a group to another layer ("Main.shp") outside of this group. The idea is for users to change values in one of the group's layers. As these layers are ...
1
vote
1answer
271 views

QGIS 2.14.3 export PostGIS layer to dxf issue

I am trying to export a PostGIS layer to dxf in QGIS (2.14.3) via Project>DXF-Export using the following settings (German GUI): When I open the resulting dxf in DWG TrueView 2016 I see nothing, but ...
1
vote
1answer
432 views

How to sum the values for bins with the same location?

I have two maps in CSV form, each has a latitude, longitude, and value column. Since not all the positions in one map are in another map, is there any way in QGIS to display a new map which only shows ...
1
vote
1answer
217 views

unable to append zero into id when updating attribute table

I want to update attribute table BID column using below line ($id +002) but it is not adding 00 at beginning. instead adding 2,3,4,5,...... I am very beginner and this is my first try to append zero ...
1
vote
0answers
399 views

QGIS 2.18.3 path and sip module cannot be load in ubuntu 16.04

I'm currently installing QGIS 2.18.3 it works fine at first, after upgrading my ubuntu the problems comes out every time I run my QGIS; it always shows "Couldn't load SIP module. Python support will ...
1
vote
1answer
253 views

Export raster with one band only using gdalwarp in extracting raster using shapefile via python script? QGIS 2.18

This code of mine is written to extract raster using a particular shapefile in PyQGIS: import subprocess, os, glob, gdal result_path = "/data/brent/bukidnon_hansen_data/result_path//" os.chdir("/data/...
1
vote
1answer
186 views

Unable to project GPM precipitation data correctly in QGIS?

After downloading the GPM (Global Precipitation Measurement) data from FTP, I tried opening the image in QGIS and I get a popup message saying CRS was undefined. As I know the projection is set to ...
1
vote
1answer
1k views

Why use QgsFeatureRequest() when iterating?

I am unclear on why one should use QgsFeatureRequest() when iterating over a file’s features. Let’s say I would like to print out all IDs in my currently active dataset. Now, most examples will ...
1
vote
2answers
4k views

Installing QGIS on Mac OS Sierra 10.12.5. “The GDAL 2.1 framework is required.”

I use the version on web("http://www.kyngchaos.com/software/qgis"). Whether I come to install QGIS 2.18.9-1 or QGIS 2.14.15-1, I click on the QuantumGIS.pkg and it opens the install dialogue box but ...
1
vote
0answers
1k views

How to fix “Unable to load GdalTools plugin. The required ”osgeo [python-gdal]“ module is missing.”

When I start QGIS, it display error message: Unable to load GdalTools plugin. The required "osgeo [python-gdal]" module is missing. Install it and try again. Couldn't load plugin 'processing' from ['...
1
vote
0answers
46 views

How would I build the syntax inside a request in the case I wanted to multiply 2 variables?

I would like add something to my previous question (here: How to build QgsExpressions in python?) How would I build the syntax inside this request in the case I wanted field_name to be also a ...
1
vote
1answer
411 views

Upgrade matplotlib used within QGIS

I'm using the Python Console within QGIS 2.14.3 (MacOS). When I import matplotlib, it imports version 1.4.3 from '/Library/Python/2.7/site-packages/matplotlib-override/matplotlib/init.pyc'. I would ...
1
vote
1answer
2k views

Calculating polygon area inside another polygon in QGIS

Is it possible to calculate the area of colorful polygons (yellow, yellowish/reddish and red) inside another shapefile (purple outline, also polygons) in QGIS. For example the polygon that is marked ...
1
vote
1answer
333 views

PyQGIS get existing ComposerAttributeTable from composition?

Working with QGIS 2.14.10x64 in Windows 7 in the QGIS Python Console I've managed to create a new print composer from a template, and update the layers in the map, and I'd now like to update the ...
1
vote
1answer
1k 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
223 views

QGIS symbology to ESRI

Does anybody know how to export the layer symbology from QGIS into a format that can be used by with ESRI products? I have been successful in exporting an XML but it quotes the file type as: !DOCTYPE ...
1
vote
1answer
934 views

Problems opening ASC files in QGIS

I am trying to open an .asc file (pick, for example, that one for 2014) from the German Federal Ministry of Transport and Digital Infrastructure. It contains information on the annual solar radiation. ...
1
vote
2answers
647 views

Rasters loaded in Postgres/PostGIS using raster2pgsql contain blank lines

I recently set up an Ubuntu Server as a Postgres/PostGIS database server. In an effort to serve a collection of aerial photos to my colleagues, I loaded 608 GeoTiffs (non-overlapping 1km tiles each ~...
1
vote
0answers
503 views

Is there way to define processing extent in QGIS?

Is it possible to define the extent of a processing tool, like it is in the "Environments" in ArcGIS? For example "Same as Display, or "Same as Layer..".
1
vote
2answers
694 views

How can I import open street map power grid data into QGIS?

I wanted to download power grid network of Cologne city from following url http://www.flosm.de/en/Power-Grid.html But I could only download in jpg format. I wanted to import this in GIS as vector (*....
1
vote
1answer
449 views

How can I serve data from a single PostGIS view, via WMS/WFS, in a way that allows users in a GIS client to filter based on attributes?

I have a materialized VIEW in PostgreSQL/PostGIS that contains observations for thousands of species. I am currently serving this view as a single WMS/WFS layer using Geoserver, and this works fine ...
1
vote
0answers
215 views

Parameters of projection for SMAP data [duplicate]

I need to extract geotiff from SMAP DATA (same without registration) I found example of gdal_translate command that do this task: gdal_translate -a_ullr -17334194 7356860 17334194 -7356860 -a_srs ...
1
vote
1answer
845 views

I can't see labels in GE of points exported from shp to kml in Qgis

I have created a shp layer in Qgis (version 2.12.3-Lyon) with points. I want to see it in Google Earth, so I saved the shp as a kml. When I open it in GE Pro, I don't see the labels, only if I click ...
1
vote
1answer
307 views

Python script to copy first row of certain attributes and paste in the newly digitised rows the copied features

Starting from this question, I need a script to be insterted in the processing graphical modeler that can copy some attributes from the first digitised row in all the newly digitised lines of a ...
1
vote
1answer
761 views

Restricting Tin interpolation in QGIS

I am trying to do a bathymetric map for a lake using QGIS. However, I see no option to impose a mask so interpolation does not extending beyond the boundaries of my lake. I have traced around the ...
1
vote
1answer
360 views

How to load an (updating) point layer from Access?

I have a database table linked to the QGIS project which contains X,Y & Z coordinate information, which I can display in the Map View window of the project, after having used the “Points Layer ...
1
vote
2answers
3k views

How to create/obtain district data for Singapore? [closed]

I am newbie in GIS and have started using QGIS. I am hoping to map all districts of Singapore and create a Shapefile and get GeoJSON details for all districts. I am not able to find that currently. ...
1
vote
2answers
753 views

Qgis2web fails to display points with SVG markers

I made a map and put some points on it and I symbolized some points as svg markers from QGis library.Now, when I wanted to display or export the map with the gis2web plugin (openlayers option checked),...
1
vote
0answers
87 views

Unable to obtain linear distance matrix [closed]

I am using QGIS 2.6 (Brighton) and when doing a distance matrix, the output csv file appears blank. Is it possible that somehow the shapefile I am using is corrupted?Has anyone please got any hints or ...
1
vote
1answer
770 views

Switch line direction for PostGIS-lines in QGIS or Pgadmin

I am trying to switch the line direction in a PostGIS-layer. The postgis-geometry column is e.g. "LINESTRING(0 0, 1 1, 2 1, 2 2)". The reason is that my symbology is direction-dependent, but I drew ...
1
vote
0answers
524 views

QGIS Layer Order Panel - add layers at top of layer order [duplicate]

I have a QGIS workspace in which the order of the layers is controlled by the Layer Order Panel. When I add a layer it automatically ends up at the bottom of the order and has to be manually shifted ...
1
vote
1answer
169 views

Where do I find the legend for netCDF files in QGIS?

I'm using QGIS to make maps of the maize, rice and wheat cultivated area at global level. I found these great netCDF files: http://www.geog.mcgill.ca/landuse/pub/Data/175crops2000/NetCDF/ Here's an ...
1
vote
1answer
368 views

Label only selected features with PAL PyQgis using an expression

I'm trying to label only selected features with an expression using PyQgis and the PAL functions, but I don't find any example and the API don't help me a lot (or I don't found it). My Qgis version is ...
1
vote
1answer
440 views

QGIS Polygon edge style based on adjoining feature?

Is there a way to change the style of only PART of a polygon's border in QGIS? I would like one or two edges of certain polygons to render a different color, or not at all, depending on the type of ...
1
vote
1answer
1k views

convert vector to raster in qgis

I'm trying to convert some vector layers(format shp) to raster, to do so I used the following method raster-->conversion-->(vector to raster) and the processing works without any problem. However the ...
1
vote
1answer
1k views

CAD line drawing to GIS polygons

I'm a (reasonably) proficient GIS user (mostly QGIS, but some Arc GIS) who has been thrown the conundrum of converting/importing CAD urban planning drawings (2D drawings produce in AutoCAD 2014) to ...
1
vote
1answer
294 views

Installing NextGIS Connect into QGIS 3?

Just acquired free version of NEXTGIS and trying to install the plugin for QGIS. It tells me it was not designed for version 3 of QGIS. How do I set up the QGIS-NEXTGIS interface then?
1
vote
2answers
629 views

How do I get UTM projected areas from a shapefile created in QGIS?

I create a polygon (or point or line) shapefile in QGIS and it is automatically saved as WGS84 (as I understand, correct me if I'm wrong). That is fine by me despite being a bit inconvenient. Then I ...
1
vote
2answers
470 views

WMS not loading in QGIS 2.6.1 Brighton

I'm using QGIS 2.6.1 Brighton, trying to load the following WMS layer: http://services.nconemap.com/arcgis/services/Imagery/Orthoimagery_Latest/ImageServer/WMSServer I can successfully load the WMS ...