Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange
The results are in! See what nearly 90,000 developers picked as their most loved, dreaded, and desired coding languages and more in the 2019 Developer Survey.

Questions tagged [qgis]

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

7
votes
3answers
3k views

Random value calculation in QGIS

Is there a way to do a random value calculation within a range in QGIS? I have been able to do this within ArcMap Field Calculator with the following code: Dim max, min max=20 min=5 x=(Int((max-min+...
2
votes
2answers
1k views

How do I create a negative to positive value raster with neutral 0?

I have a raster layer with a band with values from -137 to 9229. I want to create a color scheme showing how far from 0 the positive numbers are in one color, and how far from zero the negative ...
3
votes
2answers
572 views

How to visualize this country data in Qgis?

I have a csv table, with data in this format: "name","country". Country code is in the same format as the world map SHP file attribute table (both are in the ISO standard). I learned how to join the ...
7
votes
4answers
6k views

How can I reproduce Getis-Ord GI* hot-spot analysis tool in QGIS?

I'm trying to find a hot-spot analysis plug-in for QGIS that would perform similarly to the Getis-Ord (Gi*) hot-spot analysis tool used in Arc, but have not been successful. Does anyone have a ...
4
votes
1answer
4k views

In QGIS map composer, how do I get the Item Properties dialog back?

Yes, well if there is button there, one is bound to click it.... I closed both the Item Properties dialogs in Map Composer. And I can't get them to give me any joy no more... QGIS Trunk
3
votes
2answers
847 views

Configuring QGIS to show only toolbars wanted?

I friend of mine asked me a question the other day that I didn't knew the answer to. In his organization, they are using QGIS for non GIS-experienced people. He would like to configure QGIS to only ...
1
vote
1answer
761 views

How to handle geometry change in vector layer?

I'm building a plugin in Python that manage some lists of WKT from different intern sources (web services, bd, etc..). I can display every source without any problem. For displaying them, I use a ...
1
vote
2answers
155 views

How to display a single in a group of nodes with same attributes?

In QGIS, if I have some nodes with a name attribute is there a way to display only one node that would be in the middle of this group of nodes having the same name? For example, let's say i have 3 ...
4
votes
1answer
494 views

GPS problem in QGIS

I have a very strange problem that I cannot understand. I am trying to put together a demo-laptop with QGIS and gps. On other computers I have it working as expected, but on this particular box ...
2
votes
1answer
2k views

How to use SQLite db with QGIS plugin?

I would like to use SQLite for storing some information in my plugin for QGIS. I have a problem: if I put the db, let say test.db, among the resources as file, after compiled the resorce.qrc file, ...
2
votes
1answer
3k views

How do I automatically fill a table column?

I would like to solve a basic problem. I need to automatically fill a table in QGIS. Is it possible to fill a table according to this: if column "SPECIES" contains string "DOG" → write to column "CODE"...
1
vote
1answer
872 views

ImportError: cannot import name QgsVectorFieldSymbolLayer

I am using QGIS 1.7.4., downloaded April 2012, but receive an import error loading the class QgsVectorFieldSymbolLayer. As i understand this class has been added in the Python bindings on 2011-11-15. ...
6
votes
2answers
3k views

How to generate reports from a Shapefile?

i hope i can describe my problem. I´m into planning a guidiance system for hiking. And like it is, there will be signs with poi and the distance etc. on it. I´m collecting the data in a shape with a ...
2
votes
1answer
633 views

Why are layers not lining up with others with the same CRS? [closed]

I am creating a project on the UK and have downloaded various shapefiles. When I add a vector layer they are coming up as if they are not lining up. Some layers are nicely on top of each other with ...
1
vote
0answers
445 views

Polygon symmetry detection

I was wondering if there was any way to create main axis (axis of symmetry) lines for polygons. I have polygons that represents buildings. I will want to find main axes (axis of symmetry) for those ...
5
votes
2answers
2k views

QGIS affine - form of equation

I am at the mercy of a govt authority who have provided utility information in a cad format with a 0,0 origin and a nonsense grid. About a dozen files, the grid and origin are entirely arbitrary. To ...
2
votes
1answer
204 views

Keeping a vector layer always on top

I want to know how to keep a layer always on top of other layers! After adding a vector layer ( QgisInterface->addVectorLayer ), I want that layer to always be displayed on top of layers added later. ...
8
votes
2answers
12k views

How to get point attribute from polygon layer?

I have two layer, one (A) has point features and the other (B) has polygons. I need to produce a new table with some (the ID) or all the fields from the A table and some (the area code) or all from ...
5
votes
2answers
2k views

Display of zoomable image thumbnails instead of symbols on maps

sincere congratulations on your ingenous QGIS and the many extremely useful extensions. In my research on African archaeology I work a lot with geotagged pictures (drawings; photos; plates etc.) which ...
3
votes
3answers
2k views

How to create svg line style in QGIS?

I need to draw an telephone or energy lines as is done on the polish-core map. Thelephone line was drown by the polyline. I tried the SVG symbols, when I have a lot of single-lines, for each I 'put' ...
3
votes
1answer
873 views

Hyperlinking in QGIS - Add Data to current window

I am looking to add to my current action in QGIS so that a hyperlinked file will open in the current QGIS window, rather than in a new window. Here is what my action looks like: "C:/Program Files (...
1
vote
0answers
134 views

How to maintain schema when copying feature from layer 1 to layer 2, where both layers have same schema?

If I load two unique layers, wherein each layer contains unique data, but both layers share the exact same schema, why is it when I copy a feature from layer 1, and paste it into layer 2, the ...
4
votes
2answers
1k views

Why does the attribute Table not maintain input data?

for a longer time I have a problem with the attribute table. I create the polygons on the map, I fill up the table with attributes. Then, if I click "save", all the data from the table are being ...
4
votes
4answers
4k views

How to ceate a point layer from a table in PostGIS?

I have a table in PostgreSQL(postgis). This table has latitude and longitude values in it. Now I want to plot these point in qgis. The only thing I could get done was connecting to the database from ...
3
votes
1answer
6k views

How to open existing sqlite DB in QspatiaLite plugin?

Using QspatiaLite plugin in QGIS I'm able to create a new database and work with it (load/edit/import/export data). But how can I add a connection to an existing database? How to add an existing ...
16
votes
1answer
2k views

How to load Ordnance Survey OpenSpace in QGIS?

The version of gvSIG that I have on my Android tablet will load OS OpenSpace layers and I wonder whether or not it would be possible for QGIS desktop to do the same? And if so, how? I have my own ...
22
votes
1answer
24k views

Understanding QGIS buffer tool units?

I have been trying to figure this out for a couple weeks now and have had no luck getting the buffer tool to accept anything but degrees as units of measure. I have found lots of stuff saying the ...
2
votes
1answer
3k views

How does “Show only visible features” work in Map Composer?

If I tick show only visible, I get no features. I have created an attribute table in the Map Composer in QGIS trunk QGIS version 1.9.90-Alpha QGIS code revision 4d6cc6d I note recent feature update ...
1
vote
1answer
273 views

Python27 in Quantum GIS is missing SQL drivers in PyQT4

I am developing a QGIS plugin and need to create a table view in my GUI that I have been designing with QT Designer. I have PyQT4 installed but I have noticed that I have 2 Python directories. I have ...
1
vote
1answer
653 views

Why does Select Feature give nonsensical results?

I am a beginner with QGIS and with no previous experience or expertise in Geography or GIS. I have an ESRI shapefile of New Zealand census area units (CAUs). My goal is to obtain distances between a ...
2
votes
0answers
251 views

QGIS RGB raster layer: min/max-values defined by user not working?

I tried several times to define the min/max-values for the RGB-display under properties>style: Benutzer min/max-Werte (user min/max-values) but it is not working. By chance it worked once but now ...
5
votes
2answers
32k views

Adding points to point vector layer using QGIS?

I have a point layer with multiple data points in QGIS, but I want to add some extra data points to it and adjust some info that we missed because the ground was wet and we needed to go around it. I ...
7
votes
2answers
8k views

Labels cannot be moved although data-defined settings are active

I'm trying to manually move labels but having some trouble. I'm trying to move the labels while in edit mode. I've added fields for x coordinate (all null), y coordinate (all null), rotation (all =0), ...
44
votes
3answers
57k 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). This would avoid thematize the entire project.
7
votes
1answer
4k views

What sampling tools are available in QGIS?

I'm looking for a tool to generate a stratified random set of points within the boundaries of a polygon layer. In ftools 0.6.1 there is a tool which almost does what I need, but misses the stratified ...
3
votes
2answers
2k views

No file is created when I choose 'Save style …' in layer properties

First of all, I create a layer using the Add Delimited Text Layer plugin. The layer contains longitudinal and latitudinal data and a number that is assigned to each data point. When using a graduated ...
6
votes
5answers
22k views

How can I import georeferenced photos (jpg, kml, kmz) using QGIS or ArcGIS for Desktop?

I've got several georeferenced digital photos as jpg, kml, and kmz. How can I import them into my GIS projects (QGIS or ArcGIS for Desktop) so I can open them as a popup?
15
votes
5answers
13k views

How to split a vector into equal smaller parts in QGIS or similar?

i want to divide a shapefile with many tiles into a lot of smaller tiles. I am searching for a smart solution, because manual edits are out of questions Anyone can help or know a nice function?
2
votes
1answer
2k views

How to add USGS DRG WMS to QGIS?

Is there a WMS server, which I can be add to QGIS, that displays USGS Digital Raster Graphics (DRGs)? If so please explain how?
4
votes
1answer
375 views

Proper work flow to move manholes and pipes to surveyed location

I would like to know how to accomplish the following task using QGIS. I have an existing point shapefile representing sanitary sewer manholes and an existing polyline shapefile representing sanitary ...
1
vote
3answers
3k views

What is the problem with the merge shapefiles tool in QGIS?

I'm having trouble merging shapefiles in QGIS. I'm using plugin ftools 0.6.1 and I get this: Any workarounds someone may know of?
22
votes
2answers
16k views

Citing QGIS in formal publications?

What is the best way to cite QGIS in a formal publication? I mean, what text should be included in the References / Literature Cited section of a paper or report. I'm also specifically referring to ...
15
votes
7answers
9k views

Get Raster Values from a Polygon Overlay in Opensource GIS Solutions

I have two layers. A polygon-shape-layer with many tiles and a raster-layer containing CORINE 2006 land cover with many categories in a colourmap. I want to obtain for each polygon in the shapelayer a ...
0
votes
1answer
772 views

Tiff raster display with polygon layer

Does any body have an idea about why *.tiff images are not displayed when added as raster layer to QGIS after adding a vector layer which has a polygon geometry? SOLVED !! In fact the tiff is ...
3
votes
3answers
4k views

How to use SRTM30 Plus data with QGIS or other GIS tool?

I am trying to access the new Bathymetry data published here: http://topex.ucsd.edu/WWW_html/srtm30_plus.html Is there a way QGIS or similar tool can read these files. Nothing seems to be working, ...
4
votes
1answer
1k views

How to define a CRS using a projection rotated about a given point

I have a data set that uses a common projection, but has its own false easting and northing, and is rotated 315 degrees. I need to be able to work in this CRS and easily translate from one CRS to ...
11
votes
2answers
4k views

How to get FGDB support in GDAL 1.9 without compiling?

I was hoping that I could use the 'master' (nightly-build) version of QGIS to get fgdb support without compiliing (I'm not a developer and frankly have wasted days of productive time trying to get ...
3
votes
2answers
7k views

How to correct a wrong projection of shapefile?

I have a shapefile with UTM zone 16. This projection is wrong. It must be UTM zone 32. How can I correct the projection? When I convert (f-tool) to UTM zone 32, all the vector are rotated. The ...
3
votes
1answer
202 views

Why is the plugin list so short?

i have installed QGIS with GRASS and QDAL complete... I followed the instructions for additional QDAL configuration (adding usr/bin to the QDAL path). When i try to "fetch plugins" my list is short ...
1
vote
1answer
6k views

How to change the projection of a UTM-georeferenced raster in Quantum?

I have a project file in Quantum which contains some shapefiles and rasters that are properly georeferenced. However, I have started using GeoTiffs which are in UTM - WGS84 that don't seem to be ...