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

learn more… | top users | synonyms

3
votes
1answer
19 views

Stop Qgis layer from refreshing every time I pan

I've got a layer in a QGIS project which source is a PostGIS view. It's a quite complex view and needs like 20 seconds to load (it makes several spatial analysis). My problem is that the QGIS project ...
0
votes
0answers
5 views

Troubleshoot with “Split selected features with selected line from another layer”

I am trying to use the "Split selected features with selected line from another layer" tool from the plugin Digitizing Tools in QGIS. Sometimes, this tool works with my shapefiles but sometimes it ...
0
votes
0answers
5 views

Problem with rendering polygons Qgis2threejs

I have a polygon shapefile cotegorised according to a specific field. I want to present that 3D with the help of Qgis2three.js (sth like that). I have installed the plugin and have chosen the polygon ...
1
vote
1answer
222 views

Adding Esri imagery to QGIS using “services.argisonline.com”

I'm trying to add this particular imagery in QGIS: http://services.arcgisonline.com/arcgis/rest/services/World_Imagery/MapServer/3 But when i write the phyton srcipt i get the message that the URL ...
0
votes
0answers
14 views

How to add WMS Layer in custom projection to Qgis?

I published layer from ms-sql server on Geoserver. In sql table i have srid=60900. On Geoserver srs=60900. In Layers Previews layer looks nice. Now i tried show it in Qgis. I add projection and call ...
5
votes
2answers
85 views

QGIS 2.16 Merge lacks folder option

I've installed QGIS 2.16 and have noticed that the Merge (Vector Menu>Data Management) doesn't appear to have a Folder option anymore. This was the option that allowed you to process/merge a complete ...
4
votes
3answers
536 views

How to emulate the modulo operator in a style rule?

I have SHP layer loaded in QGIS. It consists of lines with attribute column z, containing integer value associated with line elevation in meters. Lines are drawn at 10 meter increment, and I want to ...
8
votes
4answers
1k views

QGIS choose contour line labels

Is it possible to select only one contour line for labelling? I have numerous labels for each line and I'll prefer to label only the main ones, such as 1000 m and 1500 m
2
votes
1answer
40 views

QGIS Calculate Field with Function Editor invalid expression

I have some data which is built like this: a,bbb,ccc where bbb and ccc vary in length. I want to extract the last segment of the string, after the second ",". Using the Function Editor: from qgis....
2
votes
1answer
65 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
4 views

Creating a COM object from QgsMapCanvas

I want to embed a QgsMapCanvas object to a Windows Form. I did some digging but couldn't find much about if anyone has done it before. Is this theoratically possible and/or practical?
0
votes
1answer
8 views

GRASS dependecies issues in Windows QGIS (i.vi for instance)

I have QGIS (2.14.3) and GRASS (7.0.4) desktop installed on windows 7 and have successfully installed the "GRASS" plugin in QGIS (using plugin manager). However, some of the GRASS dependencies, such ...
0
votes
0answers
7 views

QGIS Legend in print composer is corrupted

The legend in the print composer seems to be corrupted. It only shows a few items and when generated; stretches to a massive size and cannot be made smaller. This is a frustrating problem and I just ...
0
votes
1answer
17 views

QGIS Topological editing error - the new polygon overwrite the existing one after saving layer edits

I'd like to digitalizing a map and when I draw a new polygon which overlaps an existing one, at first it merges the boundaries correctly, but after i'm saving the layer edits, the new boundaries ...
1
vote
1answer
33 views

How to use the QGIS GDAL Toolbox Offset lines?

I try to create a single sided Offset line for a line. I used the GDAL-Tool "Single sided buffer and offset lines for lines" but I fail. The error message says "wrong number of arguments to function ...
0
votes
1answer
23 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? I added an image of an example (DEM raster) and a Vector Layer. It doesnt ...
0
votes
0answers
3 views

laszip batch process in qgis extension lastool

i am using qgis 2.16 in that lastool plugin contains laszip option. please tell how to run batch process in laszip. ill not able to add multiple files at a time in batch process.result came only for ...
1
vote
0answers
25 views

Three-Dimensional Routing [on hold]

I have created a route by hand using the Tracing Tool available in QGIS, placing the waypoint on top of an Open Street Map layer. I wanted to export all the coordinates to another program, so I saved ...
0
votes
0answers
20 views

QGIS “error: Grid file could not be opened” when filling sinks

When trying to run "Fill sinks" for SRTM30 data, there is a error and the log shows there was an "error:Grid file could not be opened". For the parameters: DEM: SRTM30 data; Sink route: [Not selected]...
1
vote
1answer
30 views

Why is QGIS project in recent projects greyed out?

When I open Qgis the project not able to choose. They are able when I start browser of files and click in director where projects are. Is there options to change it?
1
vote
1answer
297 views

How do you extract the data behind a raster histogram

Bit of a newbie, so this may be a daft question. I have an .ecw picture - it is has no CRS, as it is a picture taken at ground level with an NIR camera. It was originally converted from a RAW image. ...
10
votes
5answers
8k views

Qgis - Is there a way to split a polygon layer with a line layer?

I am drawing administrative regions that have boundaries follow streets in another layer. As these streets are pretty long with many vertices, I don't want to re-trace them. I am looking for a way to "...
0
votes
0answers
24 views

coordinate system are same unit also meters, but maps are not overlap [duplicate]

coordinate system are same unit also meters, but maps are not overlap WGS_1984_UTM_Zone_44N Projection: Transverse_Mercator False_Easting: 500000.000000 False_Northing: 0.000000 Central_Meridian: 81....
1
vote
2answers
279 views

Shapefile to KML Conversion Problems in QGIS 2.6.1 on Mac

I am currently using QGIS 2.6.1 on a Mac with OS 10.9.5. I am trying to export a shapefile using QGIS to KML format. I am having success with the export but the data is skewed halfway across the ...
4
votes
1answer
7k views

DXF format for QGIS

I am trying to import some DWG files into QGIS. I am using ODA to convert the DWG files to DXF and then want to use the Dxf2Shp converter plugin in QGIS. The ODA converter has many options for the ...
10
votes
3answers
10k views

ECW for QGIS 1.8 in Ubuntu 12.04

I have followed various online help guides on how to make ecw for QGIS 1.8 work in Ubuntu 12.04. I had it all working in Ubuntu 10.04 but since migration to 12.04 no such luck. Is there a guide that ...
1
vote
0answers
214 views

Problems installing libgdal-ecw package

I have problems to visualize ecw files for qgis 2.3.0 using ubuntu 12.04 LTS. From terminal, following the instructions for qgis 1.8 found at ECW for QGIS 1.8 in Ubuntu 12.04, because launching the ...
7
votes
1answer
698 views

How to get rpy2 for QGIS on OSX?

I am a new QGIS user, have installed QGIS on a Mac running Snow Leopard OSX 10.6.8 following all the instructions. QGIS seems to work well for everything other than when I boot up I get the message "...
0
votes
0answers
32 views
+100

Qgis globe plugin (2.16) missing on Ubuntu 14.04

I just upgraded from Qgis 2.14 to 2.16 and I can't get the Globe plugin to work. Apparently, under Ubuntu it is necessary to install it separately. But in the Ubuntugis repository, only version 2.14 ...
0
votes
0answers
24 views

QGIS get shape at position in shapefile

Im trying to develop an API to complement a geolocation app but I'm very new to GIS as a whole. I have a shapefile which subdivides Australian states into land zones (classifying them as Residential, ...
2
votes
1answer
156 views

QGIS: SPIT plugin not loading

Using QGIS 2.12 Lyon on a Mac (Intel, 2013). I check the SPIT line in plug-ins, but the plugin does not appear in the menu bar as promised. Log out, restart, nothing helps. Other plug-ins work fine ...
1
vote
0answers
14 views

QGIS 2.16.0 - issues with styles and rearranging attribute table columns

I'm finding QGIS 2.16.0 is not honouring attribute table column order once saved styles are applied to tables edited using Table Manager/Refactor field. E.g a new column will shift to the far right in ...
1
vote
1answer
23 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 ...
3
votes
2answers
501 views

Different definition of EPSG:3857 in GeoTools and QGIS

I want to do some checking if my point lies in any of the polygons defined in shapefile. So, I thought that I will determine CRS from shapefile (created in QGIS), and use it for transformation (where ...
9
votes
2answers
2k views

What is the difference between != NULL and IS NOT NULL?

I have a shape layer with an attribute containing NULL values to which I would like to apply a filter for values different from NULL. Using the available gui for such query construction, one would ...
2
votes
1answer
213 views

SAGA Cluster Analysis for grids projection issue

I am having an issue with the SAGA cluster analysis for grids tool within QGIS 2.4. I am actually taking this as an online class through Del Mar and we are going over supervised and unsupervised ...
0
votes
0answers
25 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 ...
0
votes
0answers
13 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 ...
1
vote
2answers
62 views

Calculate distance between two points with QGIS 2.14.0

I don’t use QGIS that much. 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 = lat/lon I want to calculate the ...
1
vote
0answers
46 views

How does NULL data effect weighted mean calculations?

I am using QGIS. I've been calculating weighted means based off a database. The database was created by combining two different sets of Data together. The Attribute Table then shows Null values for ...
1
vote
2answers
35 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 ...
1
vote
0answers
42 views

How to remove the white border of polygons using QGIS

I use the graduated color style for the polygons. But there are white borders between polygons. I tried to set Border: transparant, Border stype: No pen, Border width: 0. It did not work. I found a ...
2
votes
1answer
38 views

Why do I get “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 ...
2
votes
1answer
47 views

How to speed up QGIS vector clip?

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
0answers
28 views

How to move projects from a 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
2answers
45 views

Is it possible to import a Shapefile from Manifold into QGIS with the same projection?

is it possible to import a shapefiles from manifold to Qgis with the same projection?
1
vote
2answers
557 views

How to connect an oracle 10g database to QGIS? (TNS:Could not resolve the connect identifier specified)

Trying to connect an oracle 10g database to QGIS. I'm getting the error below: ORA - 12154: TNS:Could not resolve the connect identifier specified Anybody ever seen this error, or could provide some ...
1
vote
0answers
29 views

Is there a way to have custom functions automatically load in QGIS on start up?

I have a custom function for the print composer that prints out copyrights, but every time I start QGIS up and go to the Print Composer for the first time, I have to the Insert Expression > Function ...
13
votes
3answers
10k views

How to create polygons with straight lines and right angles in QGIS?

I am running QGIS 1.7.0 on Mac OS X 10.6.8. When creating a polygon, how do I do it so that the lines are straight (90, 0 degrees, etc.) and when I create corners they can be right angles? For ...
5
votes
1answer
233 views

Permanent Histogram Stretch with QGIS or FWTools

Is there a way to permanently stretch a histogram of a raster within QGIS or gdal? I would like to stretch a satellite image with a Standard Deviation 2.5 stretch. I would prefer to use QGIS or ...