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

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1answer
467 views

Is it possible to have auto-updating area fields?

I'm using QGIS 2.4.0 and I've noticed some problems with the derived area and the $area field. Firstly, I have a polygon which is a filled ring, inside another polygon. The derived area, and therefore ...
0
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1answer
82 views

How to set attribute to selected field?

I am trying to create a temporary point layer in memory using the following python code. # create layer vl = QgsVectorLayer("Point", "temporary_points", "memory") pr = vl.dataProvider() # add fields ...
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0answers
286 views

With QGIS, why use QT Designer tools for creating Slots/Signals/ etc, if plugin coding can do it alone

I am curious why there is facility within QT Designer to create signals and slots as, to my surprise, I did not need to do this. All of the necessary coding was accomplished completely within the ...
2
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1answer
71 views

Reprojecting from Wagner VII using QGIS

I have a shapefile in Wagner VII projection (well, the proj4 string really only is: "+proj=wag7 +datum=WGS84 +units=m"). I'd like to reproject it to WGS84 (EPSG:4326) using QGIS 2.6. However, when I ...
2
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2answers
401 views

Looking for guidance to create a hydrological map with QGIS and/or GRASS

I have QGIS and GRASS installed . Basically i need this program for making maps something like this: https://www.youtube.com/watch?v=5HuPX7JS7ZA I downloaded DEM from http://glcfapp.glcf.umd.edu:8080/...
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vote
1answer
275 views

How to label line features using python code?

I used the following code to label the line features(roads) in a layer.It works in the console, but not by python code(application) It works for the points too. What did I do wrong? Any help would be ...
3
votes
1answer
78 views

How to label states in QGIS with county-level shape

Hi I want to label state names in QGIS but my original shape file is built in county-level. If I simply label them with ``State'', my map shows multiple labels in each state as my original file (one ...
2
votes
3answers
146 views

Which monitor for working on printable maps?

I have a 24" monitor with a resolution of 1920x1080. Mostly I'm working on printable maps in QGIS. The size of some labels is sometimes smaller then 5mm on the final printed map. At my monitor this ...
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0answers
100 views

Is it normal that the installation of QGIS removes some graphical packages (12.04LTS)

When I install qgis with qgis.org deposit or ubuntugis ppa, apt wants to remove all of these packages : The following packages will be REMOVED: libgl1-mesa-dri-lts-quantal libgl1-mesa-dri-lts-...
2
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0answers
84 views

SHP, SHX and DBF files became empty (zero byte) overnight on QGIS

This literally happened overnight. I was working on a shapefile in QGIS 2.4 last night but my files (SHP, SHX and DBF) all become zero byte this morning. Has this happened to anyone before? How ...
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0answers
106 views

How to find a distance from a point to a polyline in QGIS?

Please show a sample Python code of finding a distance between a point to a polyline in QGIS. (without any plugin)
3
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0answers
51 views

QGIS isn't displaying dates in the attribute table

I have a QGIS project that links to data in a Postgres database. For some reason, QGIS is not displaying any data in date fields. The date fields appear to be fine in Postgres and I have performed ...
1
vote
1answer
303 views

How to add mdb geodatabase layer (feature class) to QGIS project using python?

I want to add a feature class of a personal geodatabase mdb to my qgs project by code (a plugin I am working on). I am using a command similar to that used for adding shapefiles, but this is not ...
4
votes
1answer
1k views

How to display multiple fields as labels if one field is null?

I am having some issues trying to show multiple fields for a single label in QGIS. In QGIS2.6, attempting to display labels for a feature consisting of multiple fields results in an empty label if one ...
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1answer
797 views

QGIS OpenStreetMap plugin: download failed. Server replied: bad request

I am trying to download Open Street Map data using the OpenStreetMap plugin in QGIS, and getting the following err: I'm kind of new on geoprocessing, so I have no clue what is going on here.
2
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1answer
31 views

How to allow the user to place a point as input for a geoprocessing model?

Is there an analogue to Esri's "Feature Set" in QGIS modeller. I am interested in creating a model that allows the user to place a point feature on a map as an input variable for a geoprocessing ...
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0answers
85 views

Why does repeatedly running the Difference Tool in QGIS stop working?

I'm having problems using the Difference tool in QGIS. When I progressively remove areas from a shapefile (a simple buffer) using the Difference tool, it seems to work fine until I get to the 5th to ...
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1answer
128 views

How to reference a return value from openProject macro?

It is very good to have available functions on startup.py, I created one to get the qgs project base name and referencing it as a Python expression on the composer thanks to all the information found ...
3
votes
1answer
242 views

How to start writing a QGIS Plugin?

I'm taking my first steps in writing a plugin for QGIS by following this tutorial: http://www.qgisworkshop.org/html/workshop/plugins_tutorial.html There is not even any functionality in this code, ...
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1answer
944 views

QGIS distance matrix in meter instead of decimal degrees

I'd be thankful for your help. i created a point layers of store locations and customers in Florida by given coordinates (WGS 84 EPSG: 4326). Now i need a distance matrix between stores and customers ...
1
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1answer
383 views

QGIS does not update data in Geoserver WFS-T

I am trying to edit a WFS from geoserver (using PostGIS data) within QGIS. This is the request as recorded by Fiddler <Transaction xmlns="http://www.opengis.net/wfs" xmlns:xsi="http://...
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2answers
738 views

How to import a .sid Raster File in QGIS 2.6.0 On Linux Mint 17

I need some help importing MrSID Raster files in QGIS. I am running 2.6.0 on Linux Mint 17. After an internet search I have found a couple of resources that are perhaps outdated. The most promising is ...
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0answers
270 views

Is there an easier way to refresh a joined CSV?

I'm working with data that gets updated sporadically. Essentially, I have a CSV which defines which postal codes belong to certain sales reps, and these postal codes might shift around. I made ...
2
votes
1answer
152 views

QGIS polygon outline color lighter

How can I make it so that the gradient classifer (look closely, there are bits of red in some places) is more pronouced? Or that the outlines of the zip codes are less pronounced?
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0answers
95 views

Creating an automatic connection to Microsoft SQL database instance in QGIS

I have connected to an MS SQL database in QGIS using the Add MS SQL table(s) tool. However I have a lot of feature in my database and so it is inconvenient to reconnect to the database every time I ...
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1answer
108 views

Saving text labels out of qgis

I have imported an OS mastermap text shapefile into qgis 2.2.0 (desktop). It only shows as points information, no text. I have edited labels so that they show (e.g. road names). The problem that I ...
6
votes
1answer
529 views

How to remove Commas from field values in multiple files?

I'm working in QGIS, presenting data in ArcMap, and Arc is having trouble with the attribute tables. I have a "species" column which lists the species found in that area and have added commas "," in ...
2
votes
1answer
456 views

QGIS field calculator expression: selecting min/max values within field groups

I am new to using QGIS (previously used Arc) and trying to get my head round the expressions and Python. I have series of polylines representing routes and require the linear distance from the ...
3
votes
1answer
274 views

How to calculate distances in QGIS field calculator?

So I'm using qgis 2.6.0 and I have a csv (converted into a .shp) with two geometry columns, I want to create a new column with the distance between the two geometry: shot.lat shot.lon haul.lat ...
2
votes
2answers
198 views

Versioning in QGIS?

Are we planning to have in QGIS implementation of Versioning like ESRI. How that can implemented? There is a general need for the the implementation where QGIS is used for planning and planned design ...
2
votes
1answer
95 views

How to export lines from ArcGIS to be used in QGIS

After a big bunch of bureaucracy we have been giving green light to request government geodata. The requested data includes mostly seperate landplots, roads and rivers. We originally were told we'd ...
2
votes
1answer
268 views

Generate territory polygon from sets of points

I'm looking for a simple way to generate contiguous "territories" from sets of points. Say, points A, B and C are in territory 1, and D, E and F are in territory 2, then generate polygons that lie ...
2
votes
2answers
186 views

How do I select a point imported from a GPX file?

I imported several GPX files and added a raster basemap for reference. The GPX files contains tracks so the points are sequentially numbered. I'd like to identify one of the points so I edit the GPX ...
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0answers
78 views

How to find QGIS or QT or Python object definitions

I am attempting a simple plugin, on QGIS 2.6, using the available QT Designer installed I have successfully loaded a plugin, and can display a dialog box with widgets, within, and now attacking ...
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0answers
925 views

Permission denied when clipping raster

Trying to use raster extraction clipper to prepare a selected area of the map for generating contours - keep getting the error message: ERROR 1: TIFFOpen:everest_gmted30.tif: Permission denied ...
2
votes
1answer
121 views

Is it possible to render a large number of shapefiles to a pdf document using Python?

I'm extremely new to GIS, and recently made a map by loading a bunch of shapefiles into QGIS using a python script. However, it took 15 mins to scroll in or out on the image, and the pdf export ...
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0answers
90 views

QGIS vector edition corrupts SpatiaLite attribute table

I have a problem with edit SpatiaLite Layer on QGIS. When I make a this set of editions: cut line, delete a part, insert a new line and save it, the attribute table is corrupted. I was thought that ...
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0answers
103 views

QGIS Processing Toolbox: otb provider XML

Good day, I am trying to integrate an OTB application into the processing toolbox. MANUALLY created a XML file for it but get : Could not open OTB algorithm: C:/OSGeo4W/apps/qgis/./python/plugins\...
2
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1answer
428 views

Fuzzy maps with QGIS/GRASSGIS

How to do fuzzy maps (FUZZY module in IDRISI) with QGIS/GRASSGIS?
4
votes
1answer
83 views

Unable to see map in QGIS?

I am new to QGIS but used to ArcGIS. I am working my way through the tutorial and have downloaded a map from earth explorer - following all the instructions. The map is in the left hand panel and ...
4
votes
0answers
385 views

Is there any reason not to upgrade to Windows 8.1? [closed]

I have the option to upgrade to 8.1, but before I do I want to see if anyone has had any compatibility issues. I mainly run ESRI, but occasionally use QGIS, and other open source products. Has anyone ...
2
votes
0answers
100 views

How do I show the file path on a map?

Can anyone tell me how to show the file path of a map when I'm composing my final map figure. Kinda of like in excel in the headers and footers options where you can show the file path of the excel ...
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0answers
224 views

QGIS Crashes with OpenLayers plugin

I've just updated to QGIS Brighton on Ubuntu 14.04, and I've noticed that when I open Openlayers plugin, in order to load google layers, the whole program suddenly crashes. The only log I see, when ...
3
votes
2answers
1k views

Calculate area in square meters from degrees?

I have a polygon shape file in geographic coordinate system, i would like to calculate area in square meters in QGIS using python. Is there any formula or equation to do this? Thanks
6
votes
2answers
902 views

ESRI Personal Geodatabases in QGIS 2.6

I am having an issue loading any ESRI personal geodatabase in QGIS 2.6. I have a number of files that worked in QGIS 2.4 and having done the upgrade I can't open them in 2.6. I have tried this with ...
4
votes
3answers
177 views

QGIS Composer thematic map : one (png, pdf, etc.) map per feature type

I've got a shapefile that contains thousands of features that can be group by categories. These features are sometime located in the same place so they overlap. An example of the content of my ...
2
votes
1answer
216 views

Convert Layer to Shapefile without losing Feature definitions

I have created a worldmap with custom defined Features, representing State/Zip-Code sales areas. I want to convert them into a Shapefile, so I can convert the Shapefile into a polygon definition file ...
0
votes
1answer
88 views

How do I measure the area difference between polygons in different shp files?

I have couple if shp files with 1000 polygons scattered in them (around 1k in each file) , each shp file represents a time frame (3 months period) and I want to show the a report with a progress of ...
1
vote
1answer
484 views

With QGIS Plugin Builder, receiving “ImportError: cannot import name”

While doing a first-time attempt to craft a simple plugin, I ran into the above error. I am using QGIS 2.6.0 for windows, the QT Designer that comes with that package, and the plugin builder plugin 2....
2
votes
1answer
2k views

How to Export to DXF and retain elevations of contours using QGIS?

I have shape files for a whole county, and have created a base map in Qgis. What I do for my projects is zoom into the area of interest then export to dxf. The same procedure was used when I used ...