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

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2
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1answer
96 views

How to do a raster reprojection in QGIS with custom map parameter

I'd need to reproject a raster dataset in a new customized projection, but I'm fairly new at both QGIS and GDAL and I'm not exactly sure about how to proceed and what the exact syntax is. The ...
2
votes
1answer
238 views

How to calculate mean coordinates from big point datasets?

I know there are several questions related to speed issues in QGIS, but I am having problems when running Ftools. I have a vector with ~70,000 points in it. When I run the generate mean coordinates ...
1
vote
2answers
1k views

Style file to QML or SLD

I have downloaded a dataset from a government organisation. it comes with a .style file. I use QGIS 1.8 on windows 7. Is there a way to use the .style file as a qml or sld? I have tried simply ...
0
votes
0answers
49 views

How to change coordinates of entire geometries in QGis

There is similar question but for ArcGIS. So how to do it in QGis? I have dataset from WWF which use different shoreline than GHHSG, in short all geometries need shifted down and left slightly.
1
vote
0answers
185 views

How to sample a raster using the Point Sampling Tool in QGIS 2.0? [closed]

I have been trying to sample raster using the Point Sampling Tool in QGIS 2.0. Though the new shape file is getting generated it does not have the values unfortunately. How do I take care of this? ...
0
votes
1answer
133 views

Problem in calculating length

I am Digitizing road line in India using open layer plugin.When I calculate the length of line using field calculator it gives me the result in millimeter . I thought it is the projection problem and ...
0
votes
0answers
113 views

How to edit the PGDB data in QGIS

I have a small query regarding the Q-GIS software. I hope someone in the know would be able to answer them. I am using 1.9.0-Master q gis. My datasets are inside a ESRI personal Geodatabase. I am ...
3
votes
3answers
1k views

OSGeo4W and QGIS 2.0

I just ran the OSGeo4W installer to update my previous installation and I noticed that it was updating my QGIS installation from 1.8 to 2.0. I haven't been able to find any information on the web ...
0
votes
2answers
184 views

Is it possible to intall the opengeostack and QGIS nightly?

Did someone managed to get the opengeostack running alongside qgis so the plugin suite-qgis-plugin can be used? I am trying it on ubuntu1304, installing opengeostack works ok, but then when installing ...
1
vote
2answers
108 views

Coordinates system in degrees in plugins for QGIS

After adding a vector layer of coordinates of settlements of a part of the world INTO QGIS 1.8, I wish to add a topographic or other nice looking, colored map. Trying plugins like maps from Google ...
1
vote
1answer
72 views

Problem opening Natural earth quick start for QGIS

Trying to open the file "Natural_Earth_quick_start_for_QGIS.qgs" a window opens, listing 20 "bad layers". The window is entitled "Handle bad layers". Consequently I cannot even get started with ...
7
votes
4answers
265 views

How to compare areas in scanned historical land use maps

I am a relative beginner to using GIS, and am running QGIS 2.0.1 in Linux. I have two historical maps which I want to analyze, that show land use patterns in the same area at two different moments in ...
7
votes
0answers
769 views

GRASS v.Overlay/QGIS Intersect Speed intersecting line and polygon

Im currently trying to convert my scripts from ArcGIS to QGIS but one aspect that is extremely slow (imo) is trying to intersect a polygon with a line feature. I feel as though there must be a better ...
4
votes
2answers
1k views

Dissolve polygons in QGIS (GEOS) with tolerance

I have a polygon vector layer representing the area inundated in a flood. The layer has been produced in a such a way that some of the areas are composed of multiple smaller touching polygons (see ...
1
vote
1answer
218 views

Save as Image geotiff from OpenLayers plugin [closed]

Now i'm working with the new version of Qgis 2.0 but I have a problem with the OpenLayers plugin. I take a geotiff screenshot of an area in EPSG:3857 and then I load the image.I'd check out the CRS of ...
0
votes
1answer
262 views

Shapfile created in QGIS does not fit in ecognition project

I have various shapefiles - some created by others, some created by my self. They should all have the same size of the underlying Raster file. The shapefiles have been created on top of a Raster file ...
1
vote
2answers
160 views

how to set width & height of a polygon in QGIS

I can't setting width and height of a polygon How to do that in QGIS? Thank you
2
votes
1answer
202 views

How to find out whether a photo is geotagged or not?

I use a android app called OSMTracker. This app records the GPS track and can take pictures and notes. Using JOSM software, the photos are shown exactly at their coordinates (location) but i cannot ...
2
votes
1answer
1k views

Implementing geometry_columns table in SQL Server for QGIS

We are using QGIS 1.8 and Sqlserver 2008.Following http://hub.qgis.org/issues/8525 solution we have created table geometry_columns. since we already have lots of table how do I fill this table ...
0
votes
1answer
102 views

Custom python scripts do not appear in SEXTANTE QGIS

Custom python scripts do not appear in Scripts menu in SEXTANTE plugin unless they are either empty or are as simple (and useless) as: ##foo=group ##input=raster OS is openSUSE 12.3; QGIS 1.8 and ...
2
votes
0answers
60 views

Error importing NOAA’s National Geophysical Data Center as delimited text layer in QGIS version 1.02

I've been struggling with trying to import the most recent data from NOAA’s National Geophysical Data Center earthquake information into Quantum GIS 1.02 for weeks now for a class assignment. I'm ...
0
votes
1answer
950 views

Can not make qgis.db private copy

I've just installed Qgis 2.0.1 and the above error message appears. Does anyone know how to resolve this problem? I think I need to change the permissions of the relevant folder, but I'm not ...
3
votes
2answers
199 views

Can QGIS display individual WMS tiles as it fetches them?

I have a QGIS project accessing a base WMS layer with imagery. How can I tell QGIS to display the individual tiles as it fetches them so that I won't wait for the whole image to load until I see ...
1
vote
0answers
93 views

Getting an error when I try to import a loaded vector file to the QGIS GRASS Plugin

I am getting an error code when I try to import a contour line vector file GRASS via QGIS. I have been trying to create a DEM from the contour lines following this tutorial: ...
0
votes
0answers
151 views

How can I embed IPython into the QGIS console?

I would like to use Ipython in the console to perform tasks more easily. How can I do that? Thanks a lot!
1
vote
4answers
265 views

How to unpolygonize and remove outermost border?

QGIS has "polygon to line" but this isn't exact reverse engineering of "line to polygon". I want no overlapped border closed lines, just segmented (on each intersected point) lines. Additionally I ...
5
votes
2answers
182 views

Time Manage + Twitter in 2013

I am a geography teacher and would love to map tweets in QGIS for my pupils. I followed all the instructions but it seems Twitter have changed the way they stream their tweets. I can cope with the GIS ...
1
vote
1answer
224 views

Restricting Tin interpolation in QGIS

I am trying to do a bathymetric map for a lake using QGIS. However, I see no option to impose a mask so interpolation does not extending beyond the boundaries of my lake. I have traced around the ...
0
votes
0answers
58 views

Can the software be installed silently?

Can QGIS be silently installed and uninstalled? We are looking to deploy this to several users for evaluation.
2
votes
0answers
354 views

How to specify cost attributes for network analysis in QGIS using the GRASS plugin?

I have a road dataset with information about the length, speed and drivetime for each segment. I use QGIS 1.9 with the GRASS plugin to do different types of network analysis, but how do I set up the ...
1
vote
3answers
430 views

Join excel attributes to shape attribute

I am wondering if there is a way to join the attributes from excel tables to shapes in Qgis. I have abbreviations in the shape and want to add the associated complete names from excel file by ...
1
vote
1answer
84 views

Snap mean coordinate to layer in QGIS and creating MCs for multiple shapefiles

1: I wish to create a mean coordinate for a group of points. However, I would like the new point to be snapped to the nearest point from the set of points used to generate it. How might one go about ...
2
votes
1answer
1k views

PyQgis question: How to change or set active layer?

Developing a qgis plugin, I found that if no layer is selected in the Layers panel I can iterate over all layers and do anything to them, but "activate" them. Could someone give me a hint please? ...
0
votes
1answer
125 views

Why does the “Dissolve” tool in QGIS create an empty layer?

I have a shapefile containing cadastral data. I would like to dissolve the polygons using my field "OwnerName". My goal is to get one polygon per landlord's name. When I use the "Dissolve" tool, QGIS ...
4
votes
1answer
382 views

Can Spatialite SQL statements be issued with a python script in QGIS?

In my previous scripting environments (ms-access and Manifold GIS), it was possible to create and execute SQL queries from withing VBA or VB Script procedures. This is really useful for things such ...
1
vote
1answer
110 views

how can i install Semi-Automatic Classification plugin manually?

I try to install with Fetch Python Plugins. But fetch python plugins show only those which are installed? can i install manually when direct installation failed repeatedly?
4
votes
2answers
861 views

How to merge TopoJSON features?

I currently have a coordinate based map of the US and it's states for topojson (https://github.com/mbostock/topojson). The coordinates are a JSON array (as topojson works), data looks like this: ...
2
votes
0answers
88 views

Convert pixel value histogram to table

I am working in QGIS 2.1 with the National Land Cover Database 2006 land cover layer. It is a raster layer with pixel values corresponding to different land cover types. I have clipped this raster to ...
1
vote
1answer
115 views

Can't get the openlayer plugin to operate [closed]

I can't get the openlayer plugin to run. I've got QGIS V1.8 on Windows 7. I've tried various repo's recommended on different sites; http://plugins.qgis.org/plugins/plugins.xml & ...
3
votes
2answers
186 views

How to determine the location that has the most intersections with other polygons in a certain distance/buffer?

I have a very scattered map with a lot of very differently shaped polygons. Now I want to determine the location where a circle polygon of a certain size intersects the most surface of these scattered ...
2
votes
1answer
68 views

Why does Fetch Python Plugins responded with only the installed ones?

I use QGIS 1.8. Whenever I demand to install plugins through Fetch Python Plugins it displays only those the already installed. I couldn't find for example; point sampling, group stats and photo2shape ...
0
votes
2answers
193 views

Intersection between points and polygons in QGis

I have the following problem. I have a shapefile of points and a shapefile of polygons. I want to know WHAT points (not how many) fall inside EACH of the polygons of my multipolygon shp. I thought ...
0
votes
2answers
410 views

Deleting points that fall outside a polygon

I have a polygon that is my region of interest. I also have a database of observation points that I have imported into QGIS as a points layer. I'd like to exclude all the observation points that ...
1
vote
1answer
277 views

What's the correct transformation for Lambert Conformal Conic for Mexico?

I have a shp archive without the .prj file. I don´t know the proyection of this shp, but I think it is in lambert conformal conic. Can anybody helpme to proyect this shp? i´ve tried to proyect it in ...
1
vote
1answer
231 views

How to install two versions of Qgis on Ubuntu 12.04?

I would like to run multiple versions of QGIS on Ubuntu 12.04. Can I do that, and how if so?
4
votes
2answers
298 views

Best practice in writing automated tests for QGIS plugins

I'm looking for some best practice advice on writing automatic tests for QGIS plugins written in Python. I have written tests for Python scripts in the past using PyUnit (the unittest module), but ...
0
votes
1answer
125 views

qgis — style edges of layer shapefiles to have thicker borders

I have two layers I'm working with here, both of North Carolina. One is "townships" the other is "counties". I want the counties shapes to have thick edges with no fill-in color. I couldn't find ...
2
votes
2answers
303 views

Can QGIS use a non-spatial Oracle Database?

I'm building my first plugin in qgis, that needs to read some coordinates from an oracle database (not oracle spatial database) and create a shapefile with this points. I'm searching but only find to ...
2
votes
2answers
216 views

How to save colour (color) ramps in QGIS

This strikes me that it should be simple, but efforts in QGIS and research here and elsewhere are not providing a solution. I have a (vector) map which I have to mark out in colours according to the ...
0
votes
2answers
290 views

How to find and replace all null values in multiple columns?

To find and replace all null values in a specific column I am using: case when "myColumn" is NULL then '99999999' else "myColumn" end But how can I use the QGIS calculator to find and replace all ...