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

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7
votes
2answers
420 views

Is there an open source alternative to ArcGIS for Desktop's Integrate tool?

I need to snap about 1000 lines in one layer to the lines in another layer (there are about 5000 lines in the second layer). The lines to be snapped are about 15 map units away from the base layer ...
3
votes
2answers
539 views

Is it possible to embed QGIS layer styles in a Spatialite database?

Spatialite is a great alternative to shapefiles - but how could I store the QGIS layer style together with the data so that it has a default style? For a shapefile I would just save a [name].qml with ...
0
votes
1answer
158 views

How to Resize the Qgis Main Window from python

I would like to write a plugin that simply resizes the qgis main window to make it small. How can I access the qgis main window through the qgis api? Use Case: We are having problems with qgis taking ...
1
vote
2answers
379 views

How to add a dynamic timeline to the QGIS canvas?

I am using the plugin Timemanager which works really great but there is one thing I'd like to improve. Instead of displaying the date and time on each frame, I would like to display a timeline ...
0
votes
1answer
322 views

How to convert OSM polyline data to polygons?

I just now downloaded OSM data .I am having the data as polylines. I want that polylines as polygons is it possible in Qgis?below I also posted the screen shot of the polyline also.
3
votes
1answer
671 views

Can Tiff files from ESRI Geodatabase be loaded into QGIS

I have been able to load an ESRI geodatabase which contains shape files into QGIS, however when I try to load a geodatabase containing tiff files I get an error message saying ...."is not a valid or ...
0
votes
1answer
191 views

eVis-Plugin centers mapwindow on coordinate origin

I have a QGIS-project with layers loaded from a postgis-database and also some shapefiles. I use the eVis-Plugin to display pictures. The displaying is working fine but after clicking on the geometry ...
3
votes
1answer
214 views

Field Value Mapping QGIS

I am wondering if there is a way to do field value maps that are filtered based on another attribute field? I know how to associate value maps, but not that are connected to another field. I have ...
0
votes
1answer
1k views

How to count number of polygons inside another polygon layer?

I am looking for a tool in arcgis 10.1 Qgis or R that allows me to count the number of polygons that are inside specific areas (defined also as polygons). My data consists in: 1 shape file with ...
2
votes
1answer
172 views

Is there any way to find the shortest distance from a point to a line?

I´m working with QGIS 1.8.0. I have a map divided into many features (thousands of small rectangles) and I have a point at the center of each of those features. I also have a map of the transmission ...
2
votes
1answer
387 views

How to handle crashes on save causing “Project file read error: unexpected end of file at line 1 column 1 for file [pathway]”?

QGIS 1.8.0 Tried to save a project and as I saved it gave me the "QGIS has experienced an error and needs to close" Next time I went to open the project I got this (well I was going to post an image ...
3
votes
1answer
69 views

Does Quantum GIS recognize QDGC information?

Good morning! So a bit of background on what I am working on: We are in the process of assisting a wildlife institution in South Africa with trying to take their information and surfacing it in a ...
1
vote
1answer
128 views

How to write a QGIS Action which opens a PDF from a server?

I need to open a PDF from an action in QGis. The PDF rests on a server, not local. So far I tried this (as Python): from PyQt4.QtCore import QUrl; from PyQt4.QtWebKit import QWebView; myWV = ...
0
votes
1answer
229 views

How to convert a .rik to .tif?

I have a quite large high-resolution map in a format called .rik from the Swedish land survey agency. I want that whole high resolution file in different format that can be used to print a map from a ...
2
votes
2answers
459 views

Is the derived area/length/xy values of a polygon/polyline layer in QGIS usable?

I have a raster that is projected to a state plane CRS and I am adding polygon/polyline shapefiles that are projected to WGS84. On the fly transformation is set to reproject to my raster CRS. When I ...
1
vote
4answers
181 views

What units are my coordinates in?

I opened a georeferenced NAIP photo to a new project in QGIS. The coordinates were expressed as: 2199240.6, 616858.7. The same point in Google Earth was expressed in degrees, minutes, seconds, as ...
1
vote
1answer
114 views

How can I create a basemap from an NAIP image using QGIS? [closed]

I unzipped the image and loaded it in QGIS as a raster. Now, how can I turn that image file into a basemap that lines up with a specific coordinate system?
1
vote
3answers
151 views

How can I create a simple basemap in QGIS that will allow me to trace a polygon with an accurate projection?

I need to find an aerial photograph, create a new vector layer, trace several fields in this aerial photograph, and find random coordinates within these polygons. I first tried this with the Google ...
0
votes
0answers
70 views

How to change API version from 9.0 to 8.1 to load PyGIS

Traceback (most recent call last): File "", line 1, in RuntimeError: the sip module implements API v9.0 to v9.2 but the qgis.core module requires API v8.1
1
vote
0answers
43 views

Why does exported map from print composer differ from map canvas? QGIS 1.8.0 [duplicate]

I have a small project consisting of a Google maps satellite open layer with two new shapefiles overlaid on it. I have then used print composer to add a grid and some labels. I have also selected lock ...
4
votes
0answers
204 views

QGIS does not read ESRI Geodatabase correctly

I have a geodatabase from the EPA that does not seem to me reading correctly with Quantum GIS. QGIS Version 1.8.0 (Lisboa) and GDAL/OGR 1.9.2 When I open the attribute table the first two columns ...
1
vote
2answers
186 views

Is it possible to change CRS without the .prj file?

I'm working with QGIS and trying to change the CRS of some maps. Is is possible to do it without the .prj file? Please let me know. Thanks.
2
votes
0answers
66 views

Loading a layer into the same position as an existing layer in QGIS

I understand that it is not possible to directly reload a shapefile layer in QGIS using the reload method in Python, since this method is not implemented for shapefile data providers. Thus, the ...
0
votes
1answer
132 views

How to divide a shapefile in QGIS

German original: ich beschäfte mich gerade mit QGIS. Ich habe über die Funktion mein Shapefile hinein geladen. Jetzt ist mein Problem: In dem Shapefile sind unterschiedliche Punkte, wie Punkte für ...
1
vote
0answers
195 views

Sources for German Standardized Symbols in QGIS

German Original: Gibt es für QGIS eine Phytonerweiterung "Planzeichenverordnung"? Zur Bearbeitung von Flächennutzungsplänen und Bebauungsplänen kommt man an den Planzeichen nicht herum. ...
1
vote
1answer
401 views

Import GPS data (text documents files) to QGis

I want to import GPS data (text document files) in to Qgis, what file format are you suppose to use ?
2
votes
1answer
198 views

Change Values of Georeferenced Raster

I am using QGIS to georeference B&W images. I have now done this and would like to set the black surround of the image (as a result of the georeferencing) to transparent but this does not work as ...
3
votes
3answers
865 views

Is there a Raster Equivalent of the Split tool?

I have the DEM of a State in ERDAS Imagine (.img) format. I have a shapefile containing the counties of that state. I want to split the whole raster into DEMs of the individual counties. The counties ...
1
vote
4answers
2k views

Python Error Message with OpenLayer Plugin

I have just recently downloaded QGIS version 1.9.90-Alpha, Alpha, 5155176. I then went to install the OpenLayers plugin. That successfully downloaded and installed, or so I thought, but when I went ...
2
votes
4answers
836 views

Unable to load GRASS plugin

I upgraded from QGIS 1.7.0 to 1.8.0, including updating GRASS to version 6.4.3. Since then, GRASS isn't any longer listed in the Fetch Python plugins. I uninstalled and re-installed the whole package ...
1
vote
1answer
795 views

Using Landsat 8 for quantitative analysis - what DNs does GRASS require?

Hoping someone can short circuit a lot of exploration Landsat 8 values are stored as unint16 since the sensors work on a range 0 to 4096 whereas the L7+TM was 8 bit and had a digital number range 0 ...
2
votes
2answers
4k views

Exporting shapefile to PostGIS database in QGIS

How do I export a vector shapefile to PostGIS database? I am asking what format I have to export it.
0
votes
1answer
75 views

how to select parts of a shape in QGIS

I have to have a Shapefile of France of the bigger regions: Ile-de-France, Bretagne, etc. and that is already included in my shape. But its only shown the Arrondissements (smaller regions) in France ...
0
votes
2answers
107 views

Attribute Table Doubt in Qgis

I am having a shape file which consists of various fields for example: shape area ,shape length, locality, sub-locality,district etc.In my company they are demanding seprate shapefiles say for example ...
3
votes
0answers
267 views

Create a path following a road, interpolating from a set of points

I have several hundred vehicular routes within a city from which I wish to create shapefiles. These take the form of directions such as "From Green Street, turn left into Brown Street, Right into ...
2
votes
1answer
112 views

Revert back from RGBA raster to original 1 band raster cell value

I have a number or single band raster grids that have been converted to RGBA (png). I no longer have access to the orignal single band raster data but have the png files. Is there a way to convert the ...
1
vote
0answers
55 views

QGIS: georeferencing report: tail cutted off

I'm using QGIS 1.8.0-2 to georeference some old maps and want to report residuals and other information via the PDF report function of the Georeferencer tool. If there's too much information, it's cut ...
0
votes
1answer
59 views

How can I use a tif and a SID to make a basemap in QGIS?

I am trying to add a basemap in QGIS, projected correctly for PA. I have been directed to PASDA. When I click on the FTP download link, it gives me the option to download TIF data or SID data. What ...
1
vote
2answers
353 views

Customise the splash image of QGIS

Where can I find the splash image which is shown while starting QGIS, and how to customise it?
3
votes
2answers
580 views

How to do a Point to Polygon analysis with multiple variables?

I have a database of almost 10k crimes, which are divided in to 10 categories and plotted on a map I also have a database of 12k addresses, which are also plotted on the map. I aim to perform a ...
2
votes
1answer
239 views

QGIS: Colour GPS track by speed

sorry íf I might ask this question the 101 time, but I didn't found anything with google or SE. I have a CSV file with WGS84 trackpoints and visualizing them with QGIS textplugin works fine. The log ...
3
votes
1answer
698 views

Manipulating Azimuthal Equidistant Projections in QGIS

I have a shapefile of world countries that is projected as Azimuthal Equidistant with Chicago, USA as the center. I would like to change the projection such that Edinburgh, UK is the center. One would ...
2
votes
0answers
241 views

How to render a transparent raster layer on top of one or more vector layers with PyQgis?

I been trying to render a map with a 3 vector layers and one raster layer. The idea is that the raster layer should be on top of the other 3 vector layers. The problem is that even when I add the ...
0
votes
1answer
86 views

Why are some features missing from Raster menu in QGIS for linux?

I am running QGIS 1.8 in Ubuntu/Linux (13.04), with GDAL 1.10 installed. There seem to be features missing from GDAL tools that are present in Windows version. For example, I can't find Rasterize or ...
3
votes
1answer
459 views

Changing the CRS of a shapefile

Im trying to convert shapefile from one CRS to another in QGIS. On the layer menu, I right click on the shapefile, save it as with other name and there I change the CRS to the desired one (WGS 84). ...
1
vote
1answer
48 views

Why are color settings not saved when exporting to a new file?

I extracted with QGIS a municipality from a state map, then divided it with a grid. I don't want the borders of the grid features to be seen so I changed the color of the map and the color of the ...
1
vote
4answers
435 views

Which UTM system do you recommend for Tamaulipas, Mexico?

I'm working with QGIS 1.8.0. Could anyone tell me which UTM system would be better to project a map of Mexico? There are too many to choose from. I have to convert my maps from WGS84 to UTM to do some ...
5
votes
2answers
1k views

How to calculate the number of cells with a given value?

I have a raster file where all cells have values between -3 and 7, no data value is -9999. Have can I calculate the number of cells with a specific value e.g. 6? Can I use the calculator?
4
votes
1answer
272 views

How can I accurately measure area of polygons using field calculator in qgis?

I have several polygon shapefiles, both set to WGS84 CRS. I have been using the google basemap with the Openlayers plugin, using the mercator CRS. On the fly CRS transformation is enabled. Should ...
1
vote
1answer
184 views

QGIS Extend Toolbar (GUI) Button Functionality via Python Plugin?

Is it possible to piggyback onto the QGIS split method via a python plugin? Are toolbar buttons accessible via the python API? This looks like the class that I need to access. Access ideas? ...