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

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1answer
74 views

Can't find the New label tools in QGIS

I can't find the New label tools in QGIS developed by sourcepole. I'm using QGIS 1.7.4. Is it a QGIS tool or a pluggin? Thanks!
2
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0answers
180 views

Sextante - SAGA- Shape to grid question?

I have a vektor shape (Index 1-5). After using the saga tool (shapes to grid) I'm getting a raster (values 1-5). The problem is that the NO DATA area is defined as 129. Is it possible to set 129 as no ...
2
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2answers
776 views

error message when clipping raster with vector layer

When I try to crop a raster using QGIS Clipper tool, I get the following error message: ERROR 1: Attempt to create 0x0 dataset is illegal,sizes must be larger than zero.. Why? The code QGIS generated ...
4
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1answer
1k views

Unit of $length in QGis Field Calculator

I'm calculating field of various features in my shapefile using QGis. I'm getting some sample length as 0.134914579766986. I want to know in what unit (eg: meters, km etc) is the above value ?
12
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4answers
4k views

Are there open-source alternatives to ArcGIS online that can be hosted on my own server?

I know this might be too broad topic. But I am looking for web-GIS portal similar to ArcGIS online that is self-installable (configurable) to be hosted in my private server. The main features should ...
8
votes
1answer
870 views

Why do vectors disappears when zooming in?

I have imported a .gpx file into qgis and separated the track waypoints using Vector > GPS > GPS tools. When viewing at full extent I can see the original track and component waypoints. However when ...
4
votes
1answer
925 views

how to add a custom SRID to Spatialite

I'd like to create a spatialite database and load it with shapefiles using the Mississippi Transverse Mercator (MSTM) projection, but it doesn't have an EPSG definition in the spatialite library of ...
5
votes
2answers
981 views

How to add a sequence to the attribute table?

Is there a way to use the field calculator in QGIS to create a range of values in a count sequence with a specified input range? For example, if I wanted to have the values 1 to 5 repeated within my ...
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1answer
6k views

Build Polygons from Polylines

I have to build the polygons from some polylines it is an area like a main land(with some boundaries) and some islands around it,islands are building polygons and main land is missing,when i have ...
2
votes
1answer
244 views

How to label a selection of an OSM layer depending on certain tags?

I just imported original OSM data to export a pdf-map by assigning graphic attributes to the features I need. The label tool in QGIS 1.8 allows to select certain features, like I can do with the ...
6
votes
1answer
726 views

How can I fix QGIS 1.8.0 Spit Plugin “connection failed”?

I want to import shp to to postgreSQL with the spit plugin. Testing the database connection to my PostGIS database ist successfully (I already imported layers with this connection via the "add postGIS ...
4
votes
1answer
87 views

Show derived rasters in titles selection QGIS

I would like to create a map in QGIS 1.8 with indexed titles which are connected with topo-map titles files (geoTIFFs). My endeavor is to make (if it is possible) layer which can react on user mouse ...
2
votes
2answers
299 views

Cannot add Plugins from Python: “Plugin is Broken”

I'm using the latest version of QGIS on a Windows 7 (32 bits), and when I try to add a plugin from the option "Fetch Python Plugins", it simply cancels the installation and I can see the following ...
1
vote
1answer
106 views

Transform csv-coordinates into area

I'm working with an inventory of a species in Southern Sweden. I have recorded my findings (together with coordinates, name of the species and year of finding) and created a CSV-file with i have ...
2
votes
1answer
654 views

Contour Lines Raster Extraction

I've been playing with Mapbox's blog post about converting heat maps to contour lines, and I'm stuck at the extraction part of this process. I used the CSV plugin to create a vector layer of points, ...
3
votes
1answer
189 views

How to find features with NULL values?

I have a layer to analyze and I want to create a thematic map with rule based feature. There is a strange behaviour. I want to find all objects with no data (NULL). All empty objects. The zero value ...
11
votes
2answers
353 views

How to sort by multiple fields at the same time?

Is it possible to sort multiple fields at the same time in QGIS? For example, I'd like to sort a table by state name, and then within each state, sort by county name. This would be the same as the ...
1
vote
1answer
75 views

Is there a free tool for configuring WMS configuration xml?

Instead of writing WMS xml file from scratch with notepad , is there a tool that is easy to create/configure such a file (or convert a GIS workspace - MapInfo / QGIS into WMS file) ?
11
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6answers
2k views

How do I make a heat or Choropleth map that uses polygons in QGis?

I've been playing around with the heatmap plugin for QGIS and I am wondering if it is possible to make heatmap with using a similar plugin/tool that uses polygons as well as points? I would like to ...
4
votes
1answer
146 views

How to aggregate point measurements in areas?

I have a shapefile with the geographical boundaries of towns in a specific region; then i have a csv file (with xy coords) with a lot of measurements about pollution in this region. I'd like to have ...
1
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2answers
549 views

How can I fix Print Composer errors due to huge file size?

I have put together a map using the British OS Strategi data set which is pretty densely detailed. It is surveyed at 1:250,000 and so contains roads down to track level, rivers, villages, railway ...
3
votes
1answer
215 views

How to get the “absolute value” of a raster cell in QGIS?

I have a raster map (-100 to +100) and I need to get all the minus values as absulute values (-100=100; -99=99...). How can I do this? Is it something like reclassify?
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1answer
84 views

Geocodin process in open source GIS tools [closed]

I want to do geocoding with open source gis tools , is it possible? if then tell me the solution? I have my village attribute data with me like addresses and contact information of persons in every ...
2
votes
1answer
413 views

How to control what kind of tags / flags are imported with osm2po?

With the help of osm2po, I have successfully inserted the contents of the italian files (italy.osm.pbf) in a pgrouting-enabled database (postgresql 8.4) It displays fine in Qgis, using rule based ...
2
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1answer
403 views

Could you suggest software to draw a cross section, companion to QGIS?

If you use GIS systems, what software do you turn to when there is a requirement to draw a cross section? Ideally a workflow that includes QGIS. Typically there are some points which will coexist in ...
5
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2answers
1k views

How to batch import GDAL supported raster files into GRASS?

I am trying to import some GDAL supported raster files into a binary raster map layer using the r.in.gdal module from QGis Grass tool. As I have multiple files to import, I would like to batch import ...
5
votes
1answer
961 views

How to get pixel size/cell size of raster layer?

After much searching, I've still not been able to figure out how to perform what seems like a simple function: I'd like to get the pixel size/cell size of a raster layer using PyQgis. Is there any ...
12
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4answers
2k views

How to buffer in pyQGIS?

I'm looking for some examples to do simple python scripts in QGIS. How would I do a buffer analysis on a dataset? I can't seem to find much in the manual and QGIS python that quite matches the Esri ...
14
votes
4answers
2k views

Are there tools to directly import QGIS projects into Tilemill?

Now that there is a tool to convert an MXD to Tilemill, one must then wonder if the ability to open QGIS documents in Tilemill will ever exist.
5
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1answer
869 views

How to load mdb geodatabases in QGIS for MAC?

I've been unsuccessfully looking for a way to add data from a .mdb geodatabase into QGIS for mac. Using the add vector layer, .mdb is not available in the filetypes, and in the database connection I ...
4
votes
1answer
353 views

NAD83 and NAD83 State Plane

I'm struggling with a projection question. I have some data in California State Plane and am trying to align a NED with NAD83. I thought these would just natively align, but they don't seem to ...
5
votes
1answer
415 views

How to calculate a standard deviation across multiple raster layers?

I have 15 raster layers. Each one shows accumulated precipitation (rainfalls) for the month of April for the same US state during a given year. So, I cover the period from 1997 to 2012. I would like ...
2
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0answers
242 views

Generate QGIS maps automatic after updating an Access 2010 or Filemaker Pro 12 database

I want to develop a database which consist an interaction with QGIS. After updating the data in the database I want to push on a button and start a process in QGIS. After finishing the process in QGIS ...
3
votes
1answer
652 views

Why are the features in my memory layer not displayed?

I am trying to create a memory layer, I followed the directions from the page below but no points appeared on my map. First I tried typing each line into the python console and I also create a plugin ...
4
votes
2answers
1k views

TIN Creation from 3D Contour File

I'm currently trying to import a 3D contour file into a Quantum GIS project. My question is, how can I export the DXF file from Microstation with height information? I already have imported it to the ...
2
votes
1answer
459 views

Creating a quality raster map in QGIS?

I've got 2 raster maps (both with the same values: 0-100). After calculating the average I need to know how precise the map is. Is there any tool in QGis? I try to explain my problem in another ...
3
votes
2answers
79 views

How to make a copy of a temp raster in QGIS?

I have a temp raster (saga raster) file. How can I make a copy of this file (like "save as")? Thank you!
2
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0answers
116 views

Is there a way to make a qgis project only editable by me

In QGIS, currently Lisboa 1.8.0 is there a way to make it only editable by me. I want to set up projects for each client on the network, so when all the files are on the network and the program and ...
3
votes
3answers
216 views

How can I draw squares in PostGIS layers at different angles?

I am trying to draw two squares on a 45-degree angle and then merge them using PostGIS to edit. QGIS can draw squares but only on a perpendicular plane (eg, 0, 90, 180), and I need to be able to draw ...
4
votes
1answer
804 views

Why don't my polygons from MSSQL2008 display in QGIS?

I have imported a polygon shape file in MSSQL2008 using Shape2SQL loader without any issue. When I import the loaded polygon file in QGIS, I can't see it ! When I import other point or line features ...
2
votes
1answer
1k views

Problem merging two rasters in Qgis

I have two rasters in Geotiff, same CRS. I tried to merge them and I have this error code ERROR 4: `C:/Anita_Tepoztln/Rasters/e142.tif' does not exist in the file system, and is not recognised as a ...
11
votes
1answer
482 views

How to associate polygons with the nearest point on a point layer? (Or … how do I assign a postal area to a salesman?)

I have a polygon layer of postal code areas and I want to use them to create sales territories based on where our sales people are based. So I assume that I need to work out for each of the polygons ...
2
votes
1answer
1k views

Rendering GML in QGIS 1.9.0

I have a set of GML geometries (see here), which I try to load in QGIS. The set contains both points and polygons, but when loaded into QGIS, only points are shown. I tried to follow this thread, but ...
6
votes
2answers
312 views

How do I compute v.kernel maps in less than 16 hours?

I am using the GRASS GIS 6.4.2 bundled with QGIS 1.8.0, using a PostGIS dataset exported via v.in.org.qgis from QGIS, to create kernel density maps. The layer has 738,288 points. My problem is the ...
3
votes
1answer
136 views

Creating rasters?

I am doing my masters in archaeology, but have used GIS for some time now, however this is my first attempt at generating and using rasters. I appear to have been successful for some, but not so well ...
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0answers
182 views

Why are my combo boxes not filled with a list of layers?

I am developing a Qgis plugin (layer_gui) and I am having a problem with populating the list of layers. When I first run the plugin my combo boxes are not filled with a list of layers, I have to ...
8
votes
1answer
2k views

Will there be an iOS version of QGIS?

I saw that QGIS now works on Android, any chance there will be an iOS version?
4
votes
2answers
843 views

Spatial query of raster data

I have population distribution data as a raster layer and exposure contours as vector (polygon) layers. What I'd like to do is use the vector layer to estimate the population indicated from the raster ...
2
votes
2answers
352 views

projection issues from ArcGIS to Qgis

I am pretty new to ArcGIS and Qgis. I have loaded some geometry data in Qgis from my postgres database, then I have also loaded the same data in ArcGIS. Then from ArcGIS i have created a shapefile ...
1
vote
1answer
497 views

Why does ftools' difference tool fail?

I have an area polygon with rocks on it i want to use difference to map the soft (ground, not rocks) cover. to do that i try using the (ftools) vector>geoprocessing>difference getting an empty ...