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

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1answer
457 views

Calculating distance between coordinates [duplicate]

I would like to calculate the distances between a list of coordinates (classic GPS coord.). From coordinate A to B from B to C from C to D and so on, and so forth. Is there any program, or website, ...
1
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1answer
47 views

The graduated symbology doesn 't take into account the attribute I need in QGIS

I m working on a project on QGIS I have a point shapefile vector that represents my store In the attribute table, i have bunch of data such as size, unit per transaction and most importantly store ...
1
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1answer
1k views

Editing WFS with max feature limit in QGis

I'm serving a large layer (500 thousand polygons) using Geoserver WFS and what to be able to edit it using QGis. I've set a feature limit on the layer so I wont overload GeoServer with the request. I ...
2
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4answers
2k views

Combining different geometry types into same feature class?

I've searched the question in this blog. Maybe I don't use the right words but anyway my problem is not present in any post so I'll try to explain my question by opening a new one. I have a polygon ...
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0answers
430 views

Zoom to Selected Feature for point layers in QGIS 2.0

I find the QuickFinder plugin for QGIS 2.0 very useful to quickly search, find, and select data. However, I'm under the impression that checking the "scale" option doesn't seem to do anything. I ...
2
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1answer
1k views

visualize bounding box to a polygon

I try to make plugin in QGIS that compare 2 bounding box data, ex: (-32.61442167739459, -32.017601026186576, 13.015663782506067, 13.428145228091406) and (-38.6102467739459, -38.017601026186576, 33....
2
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1answer
849 views

Code works on python console in QGIS but same doesn't work in stand alone script

I'm trying map rendering with stand alone script, so I have small script which works fine in python console provided QGIS, however when I run same code in stand-alone script it executes without error, ...
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0answers
37 views

Able to circumvent QgsCredentials script called from Pre-execution

I've got a stored project that, when opened is connecting to my PostgreSQL DB, and is loading several layers. All good. I'm using a script that is called from Pre-execution (Processing/Options and ...
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0answers
37 views

What can I do in qgis to manage a WMS frequently unreachable?

In my project I have a layer linked to an external WMS server (provided by a local institution). The problem is that it is somewhat unreliable: it is down rather often. Is there something I can do to ...
2
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0answers
455 views

How do I catch PostGIS/PostgreSQL RAISE messages in QGIS?

I have a trigger set up in PostGIS/PostgreSQL which will show a RAISE WARNING when an inserted or updated polygon is within a certain distance of some predefined planning constraints. I want this ...
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4answers
2k views

How to change a CSV layer attribute value from text to number - once again?

i have read most of the related postings and answers allready ... (e.g. http://anitagraser.com/2011/03/07/how-to-specify-data-types-of-csv-columns-for-use-in-qgis/ and How to change a CSV layer ...
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3answers
169 views

How to add data to an attribute table?

I have a shape file (points) and would like to add points using the attribute table and not the Add Feature tool at the main screen. I went over the Qs here, but didn't find a similar problem to mine....
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1answer
3k views

QGIS v2. Convert longitude/latitude to UTM projection-Zone 51J - Southern hemisphere [duplicate]

Could somebody please let me know in QGIS version 2.0.1 How do I convert Longitude/latitude default setting to UTM projection. I am bringing in waypoints from a GPS device which is set to the above ...
0
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1answer
115 views

QGIS-Processing GRASS-tools don't work

When I try to use the processing grass tools like r.series I always get the following messege. I deinstalled QGis and reinstalled the program totally fresh without success.
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0answers
8 views

Simple solution for escaping the QGIS locked into fullscreen mode on Ubuntu 12.04 [duplicate]

" No crash in this case, but I made the mistake of toggling to fullscreen mode on my netbook running Ubuntu 12.04. It's now impossible to escape this "No Menus" view, and it seems to have disabled ...
1
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1answer
260 views

Can one batch-automate the creation of QGIS heatmaps?

I have 4k point shapefiles, from which I would like to generate heatmap TIFFs using the QGIS heatmap plugin (or a functional equivalent featuring triweigth, radius and cell size selection). Is there ...
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2answers
251 views

What output colour format is expected by the QGIS data defined properties widget?

I'm trying to write a python function that takes a BGSREF attribute from a BGS geology shapefile and uses it to colour up the geology polygons of a shapefile. I posted my non-code working as a part ...
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0answers
141 views

Turn vector layer in raster layer based on cost

Hy, I am trying to rasterize some vector layers into raster layers and I know this is possible with QGIS by using the rasterize function in the raster menu but I don't know how to do the following ...
0
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1answer
1k views

How can I change the precision in the attribute table? [duplicate]

I'm working with QGIS, v. 2.0.1. I opened a csv-table (from an Excel-file) and now the precision is very high but I don't need this. At the moment the values are for example 15.00000000000000, how ...
1
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1answer
123 views

Tick boxes for a qgis plugin written in python

in a python plugin for qgis I want the user to be able to select one or more of several options via tick boxes. I imagine it to look like e.g. Qgis 2.2 tool "Vector" -> "Data Management Tools" -> "...
0
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1answer
98 views

Best, fast and easy way to print multiple polygons?

I´m almost sure that this is to tricky to solve. Often I have multiple combined polygons that I want to print. Until now I´ve devided all the polygons by the "Split vector layer", because I need to ...
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1answer
124 views

GEOTIFF Binary File with Color Display Issues

I have a GEOTIFF in QGIS that shows values of 0 and 1 and I want the 0 values to have no fill so that background vector layers can show through and so I can easily overlay things in a print composer ...
2
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1answer
2k views

Using Affine Transformation to expand polygons in QGIS

I have a shape file, and I'd like to grow each feature by 13.7% or 14%. The program crashes every-time I try to use affine transformation. Any recommendations? I don't have a license for ARCgis. ...
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0answers
49 views

I want to reproject data from 0-360 to -180 - 180 [duplicate]

I've been downloading data from NOAA in a CRS that goes from 0-360. The rest of my data is in -180 to 180. What's the easiest way to reproject or shift the data in QGIS? It took 30 seconds in ArcMap, ...
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2answers
210 views

Create transparent background for svg marker in QGIS?

I have an image that I want to use as a SVG marker in Print Composer. I created it as a .png file in Inkscape and then saved it as .svg. But the background transparency does not come across from the ...
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2answers
3k views

How to join MySQL database to QGIS polygons

I Have an *.sql file that has no spatial information. For every record there is an id. I also have a Qgis project with polygons without any id. How can i connect the polygons with the database? I ...
1
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1answer
125 views

QGIS combine Vectorlayer and Rasterlayer to one shapefile

I have to create some Thematic Maps, especially Choropleth Maps on Matlab. Therefore i've found a shapefile which I can use, but need to draw some lines there. I've imported my shapefile as a Vector ...
4
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2answers
223 views

Where to find Documentation for developing QGIS Plugins?

I thought I would try to write a plugin for QGIS (some Python code that I hoped I could easily port) I started following http://www.qgisworkshop.org/html/workshop/plugins_tutorial.html but that turned ...
1
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1answer
310 views

pgrouting unexpected output

Thats my ways.shp file. I loaded this to PostgreSQL DB using PostGIS shape file loader. I ran pgr_anlayzeGraph() on it and found it had a lot of isolated segments. Next I ran pgr_nodeNetwork() to ...
4
votes
1answer
438 views

four color theorem for QGIS 2.0 or Leaflet?

I recently looked at some other posts relating to this topic but as far as I can tell there is currently not a working plugin or script for QGIS 2.0 to achieve a four color theorem for styling polygon ...
4
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3answers
2k views

Per-pixel (statistical) calculations on a raster stack using GDAL

In R, it's relatively trivial to perform per pixel calculations based on a raster stack (e.g., get std.dev for each pixel on a 12 layer GeoTIFF). Unfortunately, the speed is less than desirable when ...
0
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1answer
194 views

gdal's polygonize function (via qgis) is not turning monochrome rasters into readable shapefiles regardless of inversion of color scale

I've tried polygonizing this monochrome bitmap as this: and this: and either way it ends up looking like this when (zoomed in) after gdal's polygonize operation: Is there any way I can tell ...
1
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1answer
1k views

QGIS 2.2.0 install via OSGeo4W overwrote/lost qGIS ver. 2.0

Just installed ver 2.2.0 Valmiera through the OSGeo4W advanced installer for a test drive. It overwrote existing ver 2.0 in the process. Still want to have the previous to work from. How can i get ...
1
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1answer
486 views

how to create a map with oneway flows using FlowMapper for QGIS

my plan is to create a map that shows the top 50 (by amount of passengers) international flights departing the United States (e.g. New York -> London, Honolulu -> Tokyo...). I want to use the plugin ...
0
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1answer
67 views

How do I label my map with attributes?

help is always appreciated. I have a state map in QGIS 2.0 with all of the county names and some other info listed in the attributes table. I would like to have the name of the counties and one of ...
5
votes
2answers
473 views

Raster: mosaic first, or project first?

I have a thousand raster tiles in un-projected decimal degrees from which to build a seamless mosaic in a metres-based coordinate system. The final image will be about 70,000px by 50,000px. Which is ...
5
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2answers
970 views

Load and display a layer from SQL Server using PyQGIS

I'm having a go at using pyqgis from within the QGIS python console to load a layer from SQL Server and display it. I feel like I'm part way there but I'm having a real issue getting the layer to ...
2
votes
2answers
1k views

Conversion of Latitude/Longitude to different map projection

I have two m*n matrices coming from a WRF-ARW simulation: one exclusively with longitude values and one with only latitude values. For both matrices I know the originatin projection (lambert conic ...
2
votes
0answers
381 views

QGIS 2.2 saving layer as CSV with GEOMETRY=AS_WKT not working

Just upgraded to QGIS 2.2 and it looks like saving a layer as CSV doesn't support GEOMETRY=AS_WKT anymore. The new Layer Options portion of the save dialog is cool but it looks like GEOMETRY and ...
1
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1answer
264 views

data defined labeling with postgis layer

How to use the expression based (edit: data defined) labeling with postgis? I'm wondering, whats the best way to use expression based (edit: data defined) labels with postgis (I'm new to postgis). ...
1
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2answers
311 views

How can I add custom CRS with +proj=mercxx to QGIS 2.2.0 Valmiera?

i've builded a custom proj.4 library, tested it by command line (proj and cs2cs) and with postgres/postgis. All works fine. Now i'm trying to make the same with Qgis 2.2.0. I've replaced the original ...
2
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0answers
246 views

Bivariate Mapping (running a single variable regression and mapping r-squared value)

I am hoping to produce a bivariate map displaying the correlation between two variables (specifically percent SNAP participation by county against several social variables). I would like to produce ...
1
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2answers
690 views

QGIS Valmiera, Labels only show for part of polygons

Using 2.2.0-Valmiera on Ubuntu 13.10 I have for Croatia 21 Counties as polygons. Labels show only for 12 counties: here I see that no labels are shown for multipart features. So I checked "Show ...
2
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1answer
100 views

How to properly combine and export (as raster) vector lines on top of raster

I have a georeferenced TIFF with building plans on it. I then laid topo lines on top of it. it looks right in QGis. I now want to export this as an image (i.e. with the topo lines overlaid). How do I ...
3
votes
1answer
244 views

Is it possible to distinguish between points with the same coordinates?

I have several points with the same coordinates in one layer and of course they are located on top of each other. Is there a way to separate this points automatically (not manually)? I don't want to ...
6
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4answers
2k views

How to set the transparency for multiple layers or add a global transparancy preference?

How can I set the transparency to 27 % for all 245 layers in QGIS? The only way I know of is by right clicking on the layer name, selecting Properties, then Transparency and then moving the ...
1
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1answer
160 views

Display postgis data with qgis 2.2

I have a problem with some shapefile, PolygonZ type, I have imported with "shp2pgsql-gui". This is the output (note 'coord_dimension' value): mode=c, dump=1, simple=0, geography=0, index=1, shape=1,...
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1answer
4k views

Add file GDB in quantumGIS 2.2

In QGIS 2.2.0, while adding vector layer, 'ESRI FileGDB' option was missing under Source-Type, refer the attached screenshot.In this case, how can I attach a file GDB in QGIS 2.2.0?
2
votes
1answer
802 views

How to select by attributes and calculate aggregates using Modeler?

I need to know how I can select/aggregate equal attributes in a table. This is quite the same I want to do. But I want to do it with the modeler. How to group and count attribute data? The column "...
0
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1answer
512 views

QGIS 2.0 - can't select items in Print Composer

I am having an issue where I can create a print Layout in Print Composer, but once I have clicked away from an item (like map, legend, arrow, etc) I cannot select it again.