Quantum GIS is a user-friendly, cross-platform GIS application licensed under the GNU General Public License.
1
vote
3answers
781 views
Using QGIS with a pre-existing installation of Python 3.2 and matching GDAL
I need to have GDAL/OGR working with Python 3.2 because of another dependency. However, I also want to have QGIS for convenience. However, QGIS - FWTools in particular is built against Python 2.5, ...
1
vote
1answer
2k views
Import MySQL Spatial vector layer in QGIS
I have a spatial table called 'places' in MySQL, with a spatial column 'pt' (point). I tried to import it in QGIS and no points appear. I created a view 'places_as_text' which reproduces the table but ...
0
votes
1answer
61 views
Why does Print Composer take ages “Creating icon for file …”?
Every time I open a Print Composer, a box comes up, and text flashes by saying, "Creating icon for file [various random image files that I have on my computer]". It then pauses, and does it again, and ...
0
votes
2answers
280 views
How to find the proper coordinate reference system with two sets of data using different measurements or too convert one system into another
I have two different entries of data in two different spread sheets. One of the spread sheets uses a coordinate reference system that I have no idea what the units of measurement are. the properties ...
0
votes
0answers
82 views
Is there an expert in South Devon UK willing to provide some support - happy to pay? [closed]
Recent redundancy from office with GIS staff at hand has left me highland dry - trying to get to grips with the QGIS which looks perfect for my needs yet can't even find simple instructions on where ...
19
votes
3answers
1k views
What do I need to know, to develop a plugin for QGIS?
I wish to develop a simple plugin for QGIS, which will open some data, and some specific processing.
I have quite a it of development experience with ESRI's Arcojects, but haven't developed with QGIS ...
19
votes
5answers
2k views
How do I get the best print quality from QGIS (and is Arc better)?
QGIS exceeds my expectations by a country mile. I am impressed. But;
I work with people who use Arc and they have found the best resolution output images are made by creating PDFs. They tell me that ...
29
votes
4answers
4k views
Migrate from ArcGIS to QGIS?
This is my first visit to and first question on this site, I hope this newbie question is suitable here.
Our lab has about 10 projects in ArcGIS 9 (a couple are made in ArcGIS 10) that includes the ...
17
votes
3answers
2k views
How to smooth a DEM?
I have a SRTM DEM and I want to create a shaded relief from it. I created the shaded relief in GRASS and the result is very nice, but a little rough becouse the area is near flat and the DEM is 90m in ...
11
votes
1answer
410 views
Nearest Neighbor Grouped Selection in QGIS
OK - so I have an interesting problem I am trying to solve. I have a list containing over 100,000 points in lat/long format which I have imported into qgis.
Now, what I am trying to do here is group ...
9
votes
4answers
511 views
Multicriteria Analysis : how to?
I have to do a multi-criteria analysis to answer the question : "which is the best lot to develop".
A few of the criterias are :
distance of the nearest bus stop (point layer with bus stops)
...
6
votes
2answers
405 views
How to calculate Network Service Areas in QGIS?
Is there any way in QGIS to apply service area buffers e.g if I have a point on a map I wish to show the service coverage of 1 mile, 2 mile, 3 mile, breaks using the road network?
8
votes
2answers
4k views
How to Add OSM Layer to QGIS
How can i add OSM layer in QGIS?
The help says there is an OSM plugin i can use. But i don't see it the list of plugins.
Or maybe there is a WMS URL for OSM i can use?
QGIS version ...
12
votes
3answers
460 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.
11
votes
2answers
3k views
How to use label classes, expressions, and annotations?
I've always found that when it comes to python, vector analysis, QGIS gives ArcGIS a run for its money, hell some of the qgis plugins exceed ArcGIS's performance by a few hours; however, I always have ...
4
votes
3answers
757 views
Developing Web Application For Map
I have huge data of maps usually most of the table are co-ordinates and the other are raster maps stored in SQL server 2008 and PostGres Server. I am using desktop application to analyse the data. ...
13
votes
2answers
1k views
How can I switch line direction in QGIS?
Something that is hopefully pretty easy.
I would like to be able to swap the direction of a polyline/line in QGIS. I made a custom tool to do this in MapInfo a couple of years ago, however I can't ...
9
votes
6answers
4k views
How to copy attributes from one polygon layer to another?
I have a problem that I can't seem to get my head around. I have two polygon layers:
Polygon A - is a subset of polygon B with the same fields and has identical polygons to Polygon B
Polygon B - has ...
7
votes
2answers
663 views
Is it possible to run an R script on a layer in QGIS?
I'd like to run an R script on a layer loaded in QGIS (to rotate a set of points created there using the Vector:Research Tools:Regular Points tool). I thought ManageR might work but cannot get it ...
6
votes
2answers
136 views
How to implement multivariate hex bins?
I have two point datasets that I am analyzing and I wanted to implement a multivariate hexbin approach for displaying this data.
I have managed to cobble together an approach using QGIS SVG symbols ...
6
votes
3answers
345 views
How to make transparent the background of a topographic map in QGis 1.8.0?
I'm starting to use QGis 1.8.0. I have a raster topographic map, i.e. white background and black contour lines, houses, roads and so on. I want to make transparent the white background, so if I ...
4
votes
2answers
683 views
How to install QGIS on Centos 6?
I'm new on this; I really tried a lot before ask.. but nothing works. I did all that the qgis page says. Install ELGIS. after that i investigate and tried diferents comands.. but nothing works..the ...
4
votes
2answers
382 views
Snapping two polygons together
I have a problem with two vector layers, both polygons. I have been digitising an historical map which contains large areas called townlands, filled by smaller areas called fields. I digitised both as ...
3
votes
3answers
1k views
Writing a plugin for Qgis using python to access PostGIS and write geometries
Sorry about the strange title didn't really know how to word it.
I currently use MapInfo to do most of my GIS work however I have recently installed PostGIS 1.5 and am really liking it so far. A ...
2
votes
2answers
437 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 ...
12
votes
2answers
720 views
How to generalize a polygon file and maintain topology in QGIS?
my problem: I have a polygon-file in shape-format, which I need to generalize. How can "split" the polygons into lines, generalize and than "rebuild" the polygons, so that I can ensure, that there are ...
10
votes
2answers
349 views
How to create contiguous area cartograms in QGIS or R?
Here is what I want to achieve (on the right):
I am looking for a tool or a method to transform a shapefile (with QGIS or R) into this form. And please be aware: It's not just clipping a hexagonal ...
9
votes
2answers
2k views
QGIS vs ArcGIS (features)
I am learning to use QGIS and ArcGIS but I can not find the differences between them.
What are the differences between the capabilities of QGIS and ArcGIS?
8
votes
1answer
583 views
How to add features to a PostGIS layer using Quantum GIS?
I am using Quantum GIS and the PostGIS dbms. I am able to call the PostGIS layer into QGIS but i am unable to add feature to it. I am using the method of adding features to a Shapefile but still it is ...
7
votes
3answers
440 views
Does anyone know how to install the Orfeo Toolbox in QGIS?
I already tried this http://hg.orfeo-toolbox.org/OTB-Qgis-plugins/ repository and couldn't get it...
This guy seems to have it: http://www.elance.com/samples/orfeo-toolbox-qgis/24111664/
Help, ...
6
votes
2answers
2k views
Derive WGS84 Longitude & Latitude from British Northings & Eastings
I'm looking for a fairly simple way to append columns with WGS84 longitude and latitude to a table containing northings and eastings. The source data is Ordnance Survey's CodePoint Open, which I is ...
5
votes
1answer
181 views
How to create a drop down list?
I want to show a drop down list in the feature attributes dialog.
Example:
I have 3 different building zones. The hot Wohnzon A, B residential zone and residential zone C. Now I have an attribute ...
5
votes
3answers
478 views
Spatial Query from PyQGIS?
Is it possible to reach the Spatial Query plugin functionality in QGIS from a Python script (PyQGIS)? If so, how do I accomplish this? Haven't found any documentation for it, even in the C++ API ...
5
votes
1answer
1k views
Is there a way to manually place labels in QGIS?
Is there a way to manually place labels in QGIS? I have a map which has almost-duplicate labels in some places (e.g. E 1st St and 1st St) and I'd like to remove some of them. Also, I'd like to move ...
5
votes
1answer
204 views
Seeing QGIS Python Commands
When learning MapBasic I found the most useful way to learn how to do certain tasks was to do them using the GUI and then watch the MapBasic window in MapInfo to see how they were achieved in code. It ...
5
votes
2answers
950 views
QGIS and Raster Mapping in 'Seamless' layer
I would like to use Ordnance Survey base mapping in QGIS. I would like to set up something like a seamless table in MapInfo. I think that the equivalent in QGIS is a Virtual Raster Table. The files ...
3
votes
2answers
1k views
How to connect to Postgres with QGIS?
Oddly, it should be simple, but I can't connect to a local PostGIS database. My installation is with Mac OS X (10.8), Postgres.app (in doc it's said to hava PostGIS included) and Quantum GIS 1.8.
...
3
votes
2answers
403 views
Batch Dissolve Polygons based on Attributes in QGIS or FWTools
I was wondering if anyone can help with batching a dissolve. I have a few hundred polygon shapefiles that I want to dissolve based on an attribute. I would like to do this in QGIS or FWTools. Any ...
2
votes
1answer
637 views
encoding problem with QGIS 1.8 and CSV import
I have following problem with QGIS 1.8. Lisboa (standalone installer, Win 7 Pro 64bit) - I import CSV - text in CP1250 separated with ";" and using "," as decimal separator.
I correctly set the ...
2
votes
2answers
330 views
Which labelling tool/engine in QGIS will be supported in the long term?
Why does QGIS appear to have two labelling tools?
(Note this is not new and old symbology, but that...) there are two different GUIs, one in the toolbar (which gives the Data Defined Settings option) ...
2
votes
3answers
797 views
How to extract the US from a North America Shapefile?
I have a north america shapefile, downloaded from
ftp://ftp.epa.gov/wed/ecoregions/cec_na/NA_CEC_Eco_Level2.zip
How can I get a new shapefile from this showing only us? Is there a way doing this in ...
1
vote
1answer
64 views
How to set the path to shapely?
I am using QGIS 1.8.0 on Mac OS 10.8.3 with python 2.7. Thanks to other threads in the forum, I have successfully installed shapely here:
...
1
vote
1answer
152 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 ...
10
votes
1answer
809 views
Voronoi polygons that run out to infinity
I have been working on implementing the voronoi.py script (Bill Simon's translation of Steve Fortune's code). According to the QGIS link it is basically the same code that I am working with, but the ...
9
votes
2answers
638 views
Is there a way to use “Select by Attribute” in QGIS using a python command?
is there a way to use the function "Select by Attribute" in QGIS using a python command? In my plugin the user should enter a value via a GUI and this value should be used in a function which selects ...
8
votes
2answers
569 views
How to only show labels for an arbitrary selection of items?
I'm curious how others go about solving this problem: You've created a map for something with a large number of features that are labeled. The customer/client asks that you only show labels for X, Y ...
8
votes
3answers
3k views
Can QGIS read an ODBC connection?
I have a co-worker who manages a large MS Access database that contains X & Y fields for various locations he tracks. We have previously exported the data to CSV and used the QGIS Delimited Text ...
7
votes
3answers
554 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 ...
7
votes
2answers
322 views
Can QGIS Read Spatialite Views?
I have a spatialite database I created that spans several years of crime data. To facilitate a real-world scenario where I may simplify the interaction for a user by introducing a View that simply ...
7
votes
4answers
1k views
Open source software to merge large shape files
Some background: I have 2 polygon shape files with approximately 500,000 records each. The two files are identical in terms of field structure.
Using ArcGIS 10.0 I can'nt merge these two files using ...
