Questions tagged [qgis]
QGIS is a cross-platform GIS application licensed under the GNU General Public License.
39,740
questions
208
votes
6
answers
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Adding basemaps in QGIS
ArcGIS Desktop has the option of using basemaps from ArcGIS Online.
Does QGIS have any such options?
- 3,319
184
votes
7
answers
229k
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Installing File Geodatabase (*.gdb) support in QGIS
I have spent around 2 days to find the way to open GDB (ESRI Geodatabase) in QGIS (or any other open source software) but still without success.
I have downloaded the newest OSGeo4W installer and ...
- 9,566
117
votes
8
answers
318k
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Calculating polygon areas in shapefile using QGIS
How do I calculate areas of an area shapefile in square meters (m²) or in acres (ha)?
I didn't find that functionality in the Vector Tools.
- 2,261
112
votes
5
answers
274k
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Merging multiple vector layers to one layer using QGIS
I've imported several shapefiles which where exported from a Mapinfo .tab. Several .tab-files are imported resulting in 20+ layers.
Afterwards I want to export it to GeoJSON; but I'm reluctant to ...
- 2,269
94
votes
5
answers
134k
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Renaming attributes/fields in shapefile attribute table using QGIS
I would like to rename some fields in my attribute table:
Like rename "XRF_N3"in something else. It seems quite a easy issue but I don't find any information about how can I do that.
- 2,048
87
votes
6
answers
57k
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Visualising WKT geometry string in QGIS
Is there a simple tool in QGIS to graphically visualise geometry formatted as text?
Example geometry:
POLYGON((571178 6337246,571178 6402217,598061 6402217,598061 6337246,571178 6337246))
Result:
A ...
- 4,450
87
votes
13
answers
228k
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Creating point features with exact coordinates in QGIS
How do I create point features with exact (manually entered) coordinates in QGIS?
I get precise GPS coordinates from a survey team which I need to add to a point layer. What I want: add point, type in ...
- 879
71
votes
7
answers
47k
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Generating Map Tiles with QGIS
Is it possible to generate map tiles from QGIS?
I guess QGIS Server must have a way to do it, but is there a way to just generate the tiles and save them to disk?
With the new symbology renderer and ...
- 2,917
68
votes
3
answers
78k
views
Uninstalling QGIS that was installed using OSGeo
I installed QGIS using OSGEO4W, and would love to know how to uninstall it, because when I go to "Control Panel > Programs > Uninstall" the program does not appear in the list of installed programs.
...
- 681
68
votes
5
answers
127k
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Clipping raster with vector boundaries using QGIS
In QGIS I would like to clip a raster precipitation layer using an admin boundary layer that is vector data. However the Geoprocessing tools seem to be usable only for vector data.
How can I clip this ...
- 681
65
votes
5
answers
47k
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Building effective heat-maps?
Using ArcGIS, QGIS, Grass, and/or GVSIG:
What are some of the tools and processes involved in building effective heat maps?
What are the plugins involved?
What are the major data requirements?
What ...
65
votes
3
answers
103k
views
Installing latest QGIS version on Ubuntu? [closed]
I am relatively new to Linux, so can you indicate the exact commands (step-by-step) that I need to type to get the latest QGIS installed on Ubuntu 14.04.
I have tried to follow the instructions ...
- 759
63
votes
2
answers
138k
views
Selecting features within polygon from another layer using QGIS
I'm using QGIS 1.8 with a PostGIS database and I have three PostGIS layers in QGISL: a lines, a points, and a polygon.
I'm trying to select features in the polygon layer and mark all points within ...
- 631
58
votes
7
answers
215k
views
Importing DWG into QGIS project?
I have a lot of DWG files like basemap, and water and wastewater network.
How do I import these files into my QGIS project?
- 637
57
votes
9
answers
87k
views
Missing Processing Tools in Vector Menu of QGIS
I'm missing all the usual processing tools in the Vector menu in QGIS 2.16 (e.g. Vector Overlay, Analysis, etc). They do appear in the processing toolbox but there's no sign of them in the Vector menu....
- 906
57
votes
7
answers
157k
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Getting list of coordinates for points in layer using QGIS?
I've got a layer in QGIS that is comprised of points. Its attribute table doesn't have (show) the corresponding x and y coordinates for each point. Is there a way for me to extract a list of ...
- 3,137
56
votes
8
answers
75k
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Сreating polygons with straight lines and right angles in QGIS
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 instance, how do I create a perfect square or ...
- 3,137
55
votes
5
answers
52k
views
Is there an automatic function in QGIS to package all files in a project for transferability?
In my project, I use a lot of geodata from different directories.
Now I want to give the QGIS project to a colleague (eg on a CD).
Is it possible to copy the shapes from different directories ...
- 559
54
votes
4
answers
42k
views
Making spatial view in PostGIS and adding it as layer in QGIS?
In PostGIS 2.0, I am seeking an efficient way to create a spatially enabled view that is viewable in QGIS.
I followed the context of Part 2 of @Mike Toews answer to How to create a table from ...
- 23k
53
votes
8
answers
18k
views
Switching line direction in QGIS
I would like to be able to swap the direction of a polyline/line in QGIS. I made a custom tool to do this in MapInfo, however I can't seem to find anything for QGIS.
Does anyone know of a tool to do ...
- 34.6k
53
votes
13
answers
19k
views
Seeking QGIS user interface tutorials and web resources
I wish to familiarize myself with the capabilities of QGIS up to and beyond QGIS version 3.0.
Can you recommend some good web resources and tutorials that would show me QGIS' capabilities?
I am ...
53
votes
3
answers
70k
views
Reprojecting vector layer in QGIS
I have a series of layers of lines (shapefiles) in My Project. The CRS of some are different and to merge them they all must have same CRS.
When I use Processing > Toolbox > Qgis_algorithims >...
- 531
52
votes
3
answers
56k
views
Choosing between QGIS and GRASS for simple thematic maps with different layers
I was working with GIS and remote sensing in a university and professional environment some ten years ago (ArcInfo etc), so I have some experience even though somewhat outdated.
Now I am looking for ...
- 553
51
votes
8
answers
61k
views
Using continuous color band for raster legend in QGIS composer legend?
I'm looking for a way to insert continuous colour legend for a raster layer.
I managed to create discrete symbols with values along the bar, but I would like to have a continuous bar with some values ...
- 801
51
votes
2
answers
80k
views
Understanding difference between Polygon and Multipolygon for shapefiles in QGIS?
Creating Scratch layer gives me a choice between Polygon and Multipolygon, so I started wondering how should I make use of them.
Reading a new book "Mastering QGIS" (through this answer by Joseph to ...
- 30.4k
50
votes
9
answers
49k
views
Identifying duplicate attributes in field using QGIS
I have a point shapefile with thousands of points. It has an "ID" code field that is supposed to be unique. Every now and then the data entry clerk wrongly type the "ID" creating ...
- 503
50
votes
5
answers
33k
views
Change style properties of several layers simultaneously?
I'm working on bulk data. I have a few hundred GeoTIFF images imported into a QGIS project, and I'd like to modify their layer properties - things like the no-data-value, transparency of certain pixel ...
- 621
50
votes
5
answers
88k
views
Smoothing/generalizing polygon in QGIS
Is it possible to smooth or generalize a polygon in QGIS, perhaps by using a plugin like the Generalizer Plugin for lines?
I could convert my polygons to lines, smooth them and convert them back to ...
- 8,196
50
votes
4
answers
63k
views
Where does QGIS write its error log messages?
I want to read and copypaste the error log for the crashes I am experiencing in QGIS 2.0. The error I am getting freezes QGIS so I have to ctrl-alt-del. I can see the last message in the panel, but ...
- 1,363
50
votes
4
answers
59k
views
Joining non-spatial CSV file to spatial data (shapefile) using QGIS
I have a CSV file which has postcode data in a field, but it is non-spatial e.g. no Easting and Northing.
I have a shapefile with postcode in a field and some additional data.
I want to join the ...
- 545
49
votes
4
answers
49k
views
Selecting features with NULL attributes in QGIS
How do I identify which features have NULL attributes in the attribute table of a shapefile?
When i try [field]= 'NULL' it selects the features with value = 0 (see picture)
- 5,522
49
votes
7
answers
47k
views
OpenLayers low resolution and/or shifts in QGIS print composer?
I'm having trouble with the OpenLayers Plugin of Qgis and the map composer:
If I create an OSM-background layer and if I want to export this, the OSM-Layer looks perfectly all right in the normal ...
- 2,261
49
votes
2
answers
75k
views
How do I check which version of GDAL I have and how many?
I have installed in my computer the following software:
PosgresSQL 9.3.2.3
PostGIS 2.1.1.1
QGIS 2.0.1 Dufour (this one installed through the OSGeo4w package)
QGIS 1.7.0 Wroclaw
As far as I know all ...
- 1,535
49
votes
4
answers
84k
views
Converting ArcGIS (*.mxd) file to QGIS (*.qgs) file
I recently tried to use QGIS and I wondered if you can convert a draft ArcGIS map (*.mxd file) into a QGIS project (*.qgs file). Are there any solutions available?
This would avoid thematize the ...
- 491
49
votes
1
answer
18k
views
Using GeoPackage instead of SpatiaLite, and vice-versa?
I am using now QGIS 2.18, which includes support for GeoPackage format.
I know that GeoPackage is like a replacement for Shapefile but not quite so, as GeoPackage has database capabilities. At same ...
- 644
48
votes
8
answers
172k
views
Exporting attribute table to Excel from QGIS
I have seen all the questions for how to export an attribute table to Excel from QGIS, and I try all the answers like copy paste, CSV (in fact this I do not know where to find), but none seems to be ...
- 841
48
votes
11
answers
75k
views
Is there a way of auto_increment for the ID column in QGIS
I'm creating a fictive map and so I need to create lots of points, lines and for sure polygons. Later on I export my data as geojson. But before that I aways have to go and give every element an ...
- 947
48
votes
4
answers
59k
views
Filling column with consecutive numbers in QGIS
I make a new column in my attribute table and it has a default value (for example 0). I want to (probably using the Field Calculator) have the result that row 1 has the value 1, row 2=2 and so on, ...
- 2,270
48
votes
5
answers
24k
views
Smoothing DEM using GRASS?
I have a SRTM DEM and I want to create a shaded relief from it. I created the shaded relief in GRASS and the result is very nice, but a little rough because the area is near flat and the DEM is 90m in ...
- 9,797
48
votes
8
answers
27k
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Comparing QGIS and gvSIG? [closed]
Many debutant GIS users are asking me which one is better QGIS or gvSIG. Since I use Qgis and I don't have any experience in gvSIG, I aways say that both are very nice softwares and the chose is a ...
47
votes
8
answers
33k
views
How to create svg symbols that have modifiable fill color, stroke color and stroke width?
I want to create some svg symbols for Qgis using Inkscape, those symbols must have attributes as described in the question. For the last two days, I have been experimenting as instructed by Sourcepole ...
- 1,974
47
votes
5
answers
90k
views
Splitting shapefile into separate files for each feature using QGIS or SAGA
I have a polyline shapefile with about 20 kinds of roads.
I would like to know how can I create automatically a vector file for each one.
I am aware of how to do it using ArcGIS Desktop - see ...
- 479
46
votes
3
answers
59k
views
Manually placing labels in QGIS?
Is there a way to manually place labels in QGIS?
I have a map which has almost-duplicate labels in some places (e.g. E 1st St and 1st St) and I'd like to remove some of them.
Also, I'd like to ...
- 2,917
46
votes
1
answer
64k
views
Installing QGIS plugin when offline
Due to various IT policies at my workplace, QGIS is installed on a machine that is not connected to the Internet. I wish to install a couple of QGIS plugins on this system.
I have downloaded the ...
- 41k
45
votes
9
answers
45k
views
GRASS not working with QGIS says This algorithm cannot be run
I updated QGIS to version 3.6 using OSGEO4w
When I try to run any GRASS script, I get the following error message :
This algorithm cannot be run :-( The specified GRASS 7 folder
"C:\OSGEO4~1\...
- 1,917
44
votes
10
answers
100k
views
Determining the centroid of polygons in QGIS
I have a polygon vector and I want to quickly attain the centroid of this polygon for insertion in a text document. I am working with QGIS. I searched through other questions and although some are ...
- 731
44
votes
5
answers
27k
views
Calculating average width of polygon? [closed]
I'm interested in examining the average width of a polygon that represents the road surface. I also have the road centerline as a vector (which is sometimes not exactly in the center). In this example,...
- 16.2k
44
votes
3
answers
74k
views
Displaying only selected features on map in QGIS
Not sure if this option ever existed, but the new QGIS version hides a lot of things somewhere else and this seems so simple that I'm kind of convinced it was possible to do this before.
I have quite ...
- 1,073
44
votes
3
answers
59k
views
Ignoring invalid input features with Intersection tool in QGIS?
In QGIS 2.18, when I used the Vector > Geoprocessing Tools > Intersection tool, I was able to check an option which said "Ignore NULL geometries [optional]".
Now I've downloaded QGIS 3.2 and that ...
- 2,251
43
votes
7
answers
136k
views
Creating new layer from selection in QGIS
Is it possible to create layers from selection in QGIS? I am using QGIS 1.7.4-Wroclaw.
To make it easier for others to see this, here are some pics. I used QGIS 2.0.1-Dufour.
Selecting
Saving
Adding
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