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

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1answer
2k views

QGIS: creating lines from starting to arrival points?

Is it possible in QGIS to create lines from a table storing the X,Y-coordinates of starting and arrival points? So that a line.shp is automatically created? Or exists a plugin to achieve that? ...
5
votes
2answers
1k views

How to link to external files with relative path in QGIS actions?

Objective: I have point layers with attributes contain paths to external files (visio, autocad dwg...). I want to put them all in one folder together with the project file, compress the folder into a ...
3
votes
1answer
259 views

How can I reload a csv-file within qgis

I use Qgis to illustrate the results from my Matlab simulation. Matlab produces a csv-file which is connected to a shapefile within Qgis. At the moment I have to close and reopen Qgis to show the new ...
1
vote
1answer
208 views

How can I recalculate an attribute based on overlap with another layer?

I have 2 layers: The first one is a point Layer (converted from SRTM) with height information. The second one is a polygon layer (shows the forest). I want to reduce the height value - let's say ...
2
votes
2answers
583 views

How do I fix an error starting QGIS 1.8.0 on Windows XP?

I note that the installation of qgis completed successfully. However, the log procedure returns this message: "...... Estrazione: wvhpgn.gsb Estrazione: wyhpgn.gsb Cartella di destinazione: ...
3
votes
1answer
550 views

QGIS custom CRS for map of manufacturing shop floor

I'm working on a web app that shows a map of a manufacturing plant's shop floor. I've built it in Inkscape and QGIS, but when I try to load it into Tilemill, I get a CRS error. Specifically, it ...
2
votes
2answers
203 views

Why does the map legend not update in print composer?

I'm having trouble with the QGIS map composer: If I change the map in QGIS and reopen the map composer and click on update, the legend elements DON'T update! For example: Before one certain country ...
4
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2answers
863 views

How do I get the path of a project, or layer file in PyQGIS?

I am generating new raster files from vector layers on a project. I would like to save them in the same directory as the project or layer files. How do I find this path using PyQGIS?
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0answers
38 views

Only one row displayed when opening attribut table

When running the example data for Alaska, the attribute table view for Lakes only shows the first row. All lakes are displayed in the map view.
0
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1answer
243 views

How to debug QGIS installation problems on XP? [closed]

I'm installing Qgis (Standalone 1.8) on all the PCs of the town planning office where I work. All good for 4 computers, on the fifth installation does not work. Computers have all XP with SP3. In ...
4
votes
2answers
1k views

Create custom projection using either QGIS (or ArcGIS)?

I have searched for an answer to this but don't see anything relating to what I am trying to do. What I have are a series of Geographic Coordinates, Latitude, Longitude, Ellipsoid heights. What I ...
1
vote
1answer
135 views

QGIS python plugin, segmentation fault, what can I do?

I'm trying to write a python plugin to create an input file for an urban climate model out of three shape files. Unfortunatelly QGIS closes when I try to load the plugin. When I start QGIS from the ...
2
votes
2answers
1k views

How to create a map with states by attribute value?

I'm using Qgis, but I am quite familiar with R and python. So I could use any of these. I want a map of mexico but want to color the stats according to a certain variable. It goes from 0 to 100. So ...
2
votes
2answers
321 views

How to identify image footprints of an aerial photograph

I need a tool that will take aerial images with Lat, Long, and Alt in their EXIF data and produce foot prints of the images. We need to verify that the images cover the photographed area with proper ...
10
votes
2answers
4k views

How to check Topology in QGIS?

I have two Shapefiles with Polygons ( City and Forerst) Is there a Plugin who is able check the topology (QGIS)? Like "Knots do not overlap" or something like that? I dont want that they overlap. ...
4
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3answers
2k views

Loading geotiffs into PostGIS using raster2pgsql

I have an issue with loading some Ordnance Survey raster data into PostGIS. I have been using the following raster2pgsql command to load a tif that I have placed in my C:\Program ...
3
votes
2answers
539 views

How to densify a polyline according to a specific length? [duplicate]

Possible Duplicate: Add vertices to lines I am using QGis 1.8.0 I would like to densify a polilyne according to a particular length of segment (ex. 200 m). I know it is possible with other ...
5
votes
1answer
508 views

Create point between two points with given distance or length

What I have: Coordinates of Point A and Point C and therefore vector and azimuth from A to C What I want: Coordinates of Point B (between A and C) with a distance from A to B of 35.2 meters. ...
3
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2answers
300 views

Looking for qml specification

Where I can find qml specification which is used for store symbology information in QGIS? Try to googe it - no result.
0
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1answer
664 views

Ogr2Ogr doesn't work with QGIS 1.8

I'm trying to use Ogr2Ogr.exe to import some shapefiles. It came installed with QGIS 1.8. When I try and run it, i get the following error: C:\Program Files (x86)\Quantum GIS Lisboa\bin>ogr2ogr ...
6
votes
2answers
5k views

How do I change the data type in attribute table in QGIS

I have county data in which the FIPs (actually State FIPS and County FIPS combined). I have data imported as CSV with the sames FIPS data titled STCounty. However, the shapefile FIPS is listed as a ...
3
votes
1answer
2k views

What's the proper format for WKT linestrings when importing into QGIS?

I'm trying to run the following test CSV through the Delimited Text plugin as WKT data: oid,Line 1,LINESTRING((45.554194 -122.686101, 45.433001 -122.762632)) 2,LINESTRING((45.432505 -122.598327, ...
2
votes
1answer
178 views

How can I add individual geoprocessing tool, for e.g. buffer onto the toolbar in qgis?

I am no programmer so I do not understand how to create a plugin to add a button to the toolbar. Is there another simpler way to do so? I only need a few tools from the ftools suite and do not want ...
1
vote
2answers
174 views

How to apply v.transform on a set of vector layers (GRASS 6.4)?

I have 64 vector layers, all of them must be warped using the v.transform module; the pointsfile is the same for all vectors. How can I apply the transformation recursively to all layers? I'm not ...
1
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0answers
90 views

Categorized Style : showing all possible values, not just the ones in use

I am new to QGIS and experimenting before rolling this out to my colleagues. I have a shapefile with some codes, and i have a csv with those codes and other information that i need. I have joined ...
3
votes
1answer
207 views

How can I preserve date field format when importing to QGIS?

I have a slight learning curve working here, is there a work around to importing spread sheet data without changing the type of data in the fields? i am importing some water test data along the rio ...
1
vote
0answers
318 views

Why won't this PostGIS query display in QGIS

I am having trouble rendering the following PostGIS query in qgis1.803. SELECT s.musym, st_intersection(s.the_geom,f.the_geom) as geo, nextval('"soilsplittersequence"'::regclass) as k From ...
1
vote
1answer
334 views

Is there a way of viewing a photo has a point tag from Photo2shape in QGIS?

Is there a way to view images (photos) that have location point from Photo2shape by clicking on the point in QGIS?
2
votes
1answer
317 views

Is it possible to add rings using other polygons?

I would like to "Add Rings" but using other polygons. Example: https://www.dropbox.com/s/ue1k3b646ivqedo/holes.JPG I would like to delete the two selected polygons and create holes under them in the ...
1
vote
1answer
642 views

how to get the projection from a vectorlayer in qgis?

Hi I am trying to set the projection on a raster to match that of a vector point layer. Thus I need to findout what is the projection of a give layer, to use it in the GDAL.Dataset.SetProjection() so ...
0
votes
1answer
329 views

Polygonizer plugin halts in Windows

I've had some success and some problems using the Polygonizer plugin in the past. I'm using Polygonizer 2.1 in QGIS 1.8 on Windows 7. I'm aware there are sometimes problems using Polygonizer in ...
2
votes
2answers
512 views

How do I import specific Coordinates from Namibia in QGis?

I have a map here with Coordinates from the Schwarzeck Map Datum Format 1903. They have the following format e.g.: y: 41 944,31 x:363 810,71 I want these point to be pictured in QGis... how is it ...
6
votes
1answer
561 views

Clean small artefacts from polygon shapefile

With some success, I've been generalising and cleaning Ordnance Survey OpenData VectorMap District woodland polygon shapefiles to make them fit for mid-scale mapping. However, the resulting ...
1
vote
1answer
845 views

Change coordinates of a polygon

I wanted to know whether it is possible to change the coordinates of a Polygon by typing them in. I don't want to have to manually drag them into the right position.
15
votes
5answers
15k views

How do I create point features with exact coordinates?

How do I create point features with exact (manually entered) coordinates in QGIS? I get precise GPS coordinates from a survey team which I need to add to a point layer. What I want: -Add point, type ...
3
votes
2answers
2k views

Adding georeferencing data into tiff image

I want to create a georeferenced .tiff file from a .png file. So I convert the .png into a normal .tiff file using the following command line : convert image.png image.tiff Here, all works fine, I ...
2
votes
1answer
500 views

QGIS identify features button issue

Is there anyway to get the Identify Features button in QGIS to automatically select a layer and provide the information without having to highlight it first in the layers TOC? MapInfo and ArcGIS ...
2
votes
1answer
1k views

How to save a vector layer from QGIS to Sql Server 2008 or 2012?

using QGIS, i've loaded up some administrative boundary data of New Zealand. I wish to now import this vector data from QGIS into my Sql Server 2012. Is there any way to do this with QGIS ...
1
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0answers
323 views

QGIS: opening a shapefile without an exclusive file lock [closed]

UPDATE: I did some analysis of what happens with the locking and it looks like QGIS doesn't use an exclusive lock. It just requires (non-exclusive?) write lock to the file. So this C# code fails: ...
5
votes
2answers
768 views

Where can I find documentation on QGIS C++ Plugin Development?

Is external C++ plug-in support available for QGIS? I'm having a really hard time getting started here. I followed the doc here: ...
1
vote
0answers
81 views

Why does Rotate Point Symbols tool not work on QGIS 1.7.4?

I'm having trouble with Rotate Point Symbols tool on QGIS 1.7.4, installed via the standalone installer. It just doesn't work. I can see the button on the Advanced Editing toolbar and in Configure ...
12
votes
2answers
553 views

Need a spatial database that can be used by QGIS and R

I'm quite new to QGIS and I'm searching for a simple way to create a Database that allows me to use the tables in QGIS and R. I have a lot of data stored in Excel spreadsheets wich will be used for ...
1
vote
1answer
438 views

Problem with Orfeo Toolbox integration in QGIS

I'm getting this error: OTB execution console output '"C:\OSGeo4W\bin\otbcli_MeanShiftSegmentation"' is not recognized as an internal or external command, operable program or batch file.
0
votes
2answers
441 views

How can I remove the menu bar in QGIS?

I want to create a clean user interface for my students to use QGIS. I tried to remove the menu bar using the customization in setting but I am not able to remove everything, e.g. Database, plugin, ...
2
votes
0answers
121 views

How can I trace an ANALYSIS_EXPORT error when building QGIS?

When building qgis1.8 using QT 4.7.4, I encountered the following error. I am unable to trace it: src/analysis/raster/qgsrastercalculator.h:31:24: error: variable ‘ANALYSIS_EXPORT ...
0
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1answer
89 views

QGIS exporting shapfile with proper projection

Can someone walk through the proper way to set a projection and export the shapefile so it will properly open up in another GIS program? I'm having trouble.
-1
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1answer
116 views

Deleting large portions of shapefile

I'm have a huge shapefile and I'm trying to delete large portions of it. I can't seems to do it in the edit mode. Can someone please walk me through this process? I'm using QGIS 1.8.
4
votes
1answer
464 views

How to Create a raster layer from a numpy array using pyqgis?

I am working on a plugin for Qgis to calculate spatial Kernel density maps. I have all the calculations working, all I am missing is a way to turn a Numpy Array, with density values into a multiband ...
1
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0answers
58 views

Can't open exported data

I downloaded data here: https://nycopendata.socrata.com/dataset/Pavement-Edge/gydf-ksfn I opened this up in QGIS but when I export it I can't open it up in another GIS program called indiemapper. ...
2
votes
0answers
48 views

How to open GDB files using QGIS in a Mac? [duplicate]

Possible Duplicate: How to get “.GDB” Esri File Geodatabase in Qgis for MAC OSX 10.6? I have some data located here: ...