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

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1answer
131 views

Get feature while editing

I have created my custom form for features editing, using layer.setEditForm("form.ui") and layer.setEditFormInit("init") properties. init method receives dialog, layerId and featId as arguments. ...
0
votes
1answer
91 views

Can you reduce the number of contour lines? [duplicate]

Using QGIS, is it possible to reduce the number of contour lines in a hypsography (topographic) layer? Mine has them every 5 meters, which is more than I need and it makes the map awfully busy.
2
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0answers
126 views

oil palm stand census algorithm

Anyone have experience in oil palm stand census using tree detection algorithm from satellite images in ArcGIS or QGIS? any references for usable algorithm? What is the accuracy? thanks for help.
0
votes
1answer
279 views

Using macports python 2.7 with macports qgis

I installed qgis through macports on my mac running OSX 10.8.2 but when I run the application (qgis 1.8) it says that I don't have python-gdal installed. I searched google and it appears that it is ...
0
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0answers
57 views

Adding a new attribute to shapefile from Excel sheet [duplicate]

I have a shapefile in QGIS and I needed to add a attribute to the attribute table. The problem is that I have the information I need to add in an Excel file. How can I add the information from the ...
1
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0answers
94 views

How can I create a multi layer exportable file (.xcf .psd) from multiple raster image in QGIS?

I have many raster file of the same zone but in differents spectral bands. I would like to create an exportable file of a small portion that can handle different layers. So in practice I would like to ...
3
votes
2answers
260 views

Where is QGIS installation path in Ubuntu

I can't find the QGIS installation path in ubuntu 12.10
2
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0answers
178 views

Plot csv data on a map

My boundaries shape file has the following attributes; CODE, PROVINCE, AREA, SHAPE_LENG and SHAPE_AREA (note that there are no geo- coordinates). My data on the csv file has the following fields; ...
2
votes
1answer
130 views

Keep .gdb structure to postgresql + PostGIS (Feature dataset)

I have a .gdb file with a specific structure. I will extract all shp files for uploading to a postgtresql db. But I want to keep the structure of gdb. How can I keep this structure to ...
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0answers
49 views

how can i plot news stories to show how many stories include each country on a map of the world

We have a table that shows the number of news stories that include particular countries over a set period of time there are three news channels that we have this data for and we would like to show/ ...
5
votes
1answer
799 views

Save Visible WMS layer to file

Is there tool to save currently visible WMS layer to file in QGIS, or some place in QGIS where you can get needed xml to fetch it using gdal ?
2
votes
1answer
153 views

QGIS: Label every other feature

How would I go about labelling every other feature in QGIS (1.8)? For example I have a set of contours every 10meters from 0m to 100m. How would I label only every 20meter contour? e.g. label ...
3
votes
2answers
216 views

Layer not aligning after georeferencing using BC Albers

I'm currently having trouble with the georeferencer... after what appears to be successful georeferencing, the map image layer does not align to the vector data. I'm trying to use BC Albers ...
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2answers
141 views

QGIS Holux gpx file doesn´t show up

I´ve got a problem with displaying the imported gpx file. The gpx file is created in Holux Funtrek 130 PRo. The map I use is from Openstreetmap, I am sure it is the right map from the location I ...
10
votes
3answers
521 views

Contours: Interrupt contour lines beneath a elevation number

Is there a way to interrupt a contour line beneath a elevation number? Thanks!
1
vote
3answers
157 views

How do I active “Open GRASS tools”-button?

I have opened to GRASS layers and need to use the "Open GRASS tools"-button. This button remains unactivated somehow. Whilst the "Edit GRASS vector layer" right next to it works perfectly fine. What ...
3
votes
2answers
163 views

Merging polygons at county level to state level

I have a shapefile that represents counties (admin 2) only, but I need to create a state level (admin 1) polygon file (I'm using QGIS). I will need to sum up (or average) the relevant data at each ...
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0answers
89 views

Looking for similar tool (like ArcGIS Diagrammer) in open source for QGIS?

Is there any diagrammer tool available (similar to ArcGIS Diagrammer) for QGIS? thanks in advance : )
0
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0answers
109 views

Unable to open old qgis files into the new version ( 1.8.0)

I have downloaded QGIS today for my school work also my Qgis version is 1.8.0 and my school's QGIS version is 1.7.0. So My new Version QGIS cannot run the QGIS file they have send me So Please help ...
1
vote
1answer
164 views

Merge 2 layers based on an attribute column in QGIS [duplicate]

I have a vector shapefile map that is divided into polygons. I want to add 2 columns to the attribute table with the eastings/northings coordinates of each polygon centroid. So far what I've tried ...
1
vote
1answer
285 views

How to create routable network by pgrouting with assign_vertex_id?

I'm trying to create the routable network as per http://underdark.wordpress.com/2011/02/07/a-beginners-guide-to-pgrouting/and use assign_vertex_id. Do I still need to create the node table? How would ...
3
votes
1answer
1k views

Qgis OpenStreetMap plugin misbehaviour

I used the plugin successfully. But yesterday, after changing several buildings in JOSM. Import under qgis with the plugin does not work anymore. The buildings are in the layer point! Do you have any ...
2
votes
1answer
171 views

How to reclassify grey scale tiff in qgis

I downloaded a raster image of the sea floor age. The values in band 1 ranges from -32768 to 32767. I need to reclassify it to no. of million of years to make sense of the data. How can I do so? I try ...
5
votes
3answers
144 views

Why does a layer imported from GPS have lat/lng rather than project coordinates?

I am importing tracks from my GPS using the GPS Tool in QGIS. I check the layer CRS and it shows WGS 84 but when I try and view the layer in my project which has a CRS of EPSG:2193 the coordinates are ...
1
vote
1answer
532 views

how to install networkx python in QGIS

How to install and how to compile networkx python on QGIS? I always get an error that no module named networkx in the console of QGIS I copied the file networkx in C:\Program Files\Quantum GIS ...
0
votes
2answers
282 views

QGIS crashes by opening project

Suddenly I got a problem opening the project I was working on since a long time. When I open the project, QGIS crashes. I think the problem might be in one layer, but as I cannot open the project I ...
0
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1answer
100 views

QGis different results between $length and measureing in the map

I use QGIS Lisboa and need the lenght of some shapefiles. When I use the field calculator the results are always around 30 % higher than in real, also than a measuring in the map. Does anybody have a ...
0
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1answer
473 views

Microsoft visual studio run time library error in Qgis 1.8

When i open Qgis project, I get an error from Microsoft Visual C++ Runtime Library: Runtime Error! For other machine its working fine.Since I have uninstalled and re-installed the Qgis,but still same ...
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3answers
2k views

How to auto fill or delete sliver polygons without losing precision?

I am developing some boundaries in which precision holds the key value. Using ArcGIS 9.3 I am converting lines to polygons using the "feature to polygon" tool. The lines are accurate but I find ...
2
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0answers
82 views

select by location

When performing an overlay or intersect I would like to know if there is a way to ignore selection when intersection or overlay is less than a certain percentage of area or less than a certain number ...
0
votes
1answer
276 views

How to properly add a Python Module to a Plugin?

I've been trying to use a module that is installed in my local version of python, but whenever I open the plugin itself, it does not manage to locate said module. The module in this case is Noise ...
3
votes
2answers
288 views

Adding a GIS feature to existing database entry with QGIS

I've built a database with postgreSQL with tables, which include geometry columns. When I add some data to my non-geometry columns, I can see them in QGIS when I connect to my database using postgis. ...
0
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0answers
75 views

What vector file type yields the greatest detail with the Heat Map plugin?

I'm using .shp files built from .csv files and having quirky results. Perhaps there is a better way to begin. The heat map appears to be accurately describing the data but calculates a huge area in ...
9
votes
2answers
378 views

How do I generate a large number of maps?

I have to make a large number (hundreds) of distribution maps of species. I have a shapefile that contain the distributions for each species, and for each one, I would like to get a map as an image ...
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0answers
265 views

Can I create a custom Shapefile for SAS with QGIS?

Okay - I am in the process of configuring GIS within our organisation and am waiting for QGIS to be installed. My aim is to use QGIS to compile a custom shapefile of the business regions used by our ...
2
votes
1answer
2k views

How does Quantum Gis work with Arcgis .xml files?

I'm not familiar to quantum gis, so can anyone explain if it is possible to import/export xml files in quantum gis? If it is possible, how can I do that? I exported some . xml recordset and workspace ...
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0answers
174 views

QGIS plugin 'sextante' not loading after upgrading to Mac OS X 10.8

Any known issue with sexante and Mac OS X 10.8? After updating from 10.7 and even after reinstalling GDAL sexante is still not working...
5
votes
3answers
701 views

How to drape a simple jpeg image over dem of some area?

How can we drape a simple jpeg image which doesnot have any geo referencing information over the digital elevation model in order to visualize it in 3D in QGIS?
0
votes
2answers
249 views

QGIS 1.8 crashes when exporting from print composer to image on Windows 7

My question is similar to QGIS Crashes when writing to PDF. Today, when I try to export to image, QGIS crashes. I've tried opening a new composer to no avail. This is the problem signature: Problem ...
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0answers
105 views

'File is too big' error when uploading QGIS Plugin

I have written a simple QGIS plugin which zooms the map canvas to a user specified UK postcode. I would like to share the plugin but the csv file, which contains stripped down OS Code-Point open data ...
2
votes
1answer
359 views

How to interactively get the coordinates of a point in QGIS

I have a shapefile with a single layer of type point. It is in the google CRS (EPSG:900913). When I use the 'Identify Feature' tool it gives me lots of information about the point clicked on, but I ...
2
votes
2answers
873 views

Can't open Spatialite db from openstreetmap in Quantum GIS

I am new to QGIS, OpenStreetmap and Spatialite. I'm trying to get the (OSM) map data into a (SQLite) compact form I can eventually use for realtime reverse geocoding in a vehicle. Quantum is just for ...
3
votes
1answer
616 views

Can the units of the measure tool in QGIS be changed?

All, I'm trying to do some error-checking with some rasters I'm creating, and want to measure line distances on the map in feet, rather than meters - which is what the measure line tool seems to be ...
2
votes
2answers
315 views

Selecting lines occupying identical positions in MapInfo or QGIS

I have two shapefiles from a client, one is their entire network (complete with unique IDs) and another a selection I need. However the selection file does not have unique IDs but the entire one does. ...
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0answers
82 views

mapCanvas.saveAsImage not functioning as expected in QGIS 1.8

I have a plugin for exporting maps as PNG images. I believe this code was working correctly within 1.6 (but I cannot guarantee I haven't made another change that would have broken it there, too). ...
3
votes
2answers
949 views

How to create a multipart polygon?

I have two polygons that consist of two separate polygons/lines in QGIS). How can I make this into a multipart polygon, which consists of 1 line in QGIS?
1
vote
1answer
723 views

Illustrator to QGIS workflow for vectors

I vectorized a map in Illustrator and would like to import it to QGIS now. I know I must use DXF for that purpose but when I convert the DXF to SHP with the QGIS plugin it is not georeferenced which ...
2
votes
2answers
138 views

How do I stop null values from being assigned extreme color values?

I have a raster surface that I kriged in Surfer and imported to Grass GIS but when I view it in QGIS, the null values outside of the interpolated surface take an extreme value and wash out the ...
1
vote
2answers
139 views

Problems with Combining Layers in QGIS

I am trying to add the political boundaries baselayer from http://www.cec.org/Page.asp?PageID=924&ContentID=2336 and then on top add points where I gathered coordinates from Google Earth (using a ...
3
votes
1answer
497 views

How do I use the GRASS command line tools within QGIS?

How do I use the GRASS command line tools within QGIS? I use the QRASS plugin to open the mapset, and then I open the GRASS tools window. I click on 'GRASS shell' under modules and it brings up a ...