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

learn more… | top users | synonyms (1)

3
votes
2answers
3k views

how to convert qgis generated tiff images into jpg/jpeg using gdal command line utilities?

I want to develop a web portal that will show the images dynamically produced by qgis . but qgis provided tiff images are too big in size and it is not possible to show it on website using image ...
2
votes
2answers
278 views

Losing large portions of elevation contours from QGIS to PDF

Please forgive me as I'm new to GIS and all this might be a silly question, the wrong place for this question, or a hack way of going about what I'm getting at. So any suggestions on better practice ...
3
votes
1answer
170 views

Is it possible to mimic ArcPublisher with PDF or similar?

I want to provide mapping output in a format that mimics the delivery provided by ArcPublisher and wonder if anybody has any experience in this. For instance, the PDF format now supports layers ...
5
votes
3answers
8k views

How to create a new layer from a selection in QGIS?

I have been using ArcMap for the last three years. But I am now considering switching to Quantum-GIS. Is it possible to create layers from selection in QGIS? I am using QGIS 1.7.4-Wroclaw. UPDATE: ...
1
vote
1answer
533 views

How to create a worldfile by bounding box?

I need to create a worldfile from Bigmap Application. I've successfully to grab a pack of PNG tiles and the pearl app mosaicking all in one. The BigMap site shows the raster bounding box and util ...
1
vote
1answer
193 views

QGIS not reading colormap from hand-edited .qgs file

I have a set of rasters which store solar radiation incidence over the course of a year. In QGIS, I want to map the same extent, and with the same reference features, varying only the solar raster ...
1
vote
1answer
327 views

How to Make QGIS on Windows use Spatialite 3.0 instead of 2.4?

I spent all afternoon trying to figure out why my complex triggers are working fine in Spatialite-GUI but QGIS refuses to write to the layer. Finally remembered I ran into a similar issue a few ...
2
votes
1answer
532 views

How to transpose the lat/lon coordinates of a shapefile?

I need X to be Y and Y to be X (switching lat/long) within the polygon shapefile. If it were a point shapefile I know I could simply reverse the lat/long or x/y parameter and import from a table. I'm ...
1
vote
1answer
178 views

How to move the last vertex till the last angle is squared?

I have problem using Orthogonal Digitizing button from CAD Tools plugin menu. It moves the first point of the polygon by holding ctrl key pressed and pressing right mouse button till the last angle is ...
4
votes
3answers
2k views

How to read the GEOMETRY table inside a sqlite database

I'm working on an android app which should display some lineobjects stored in a sqlite database. This sqlite database is created through an export in QuantumGIS. My first question is it a real ...
1
vote
1answer
309 views

How can the scale be projected correctly in Quantum GIS when it is imported from google earth (KML) files?

While importing KML files from google Earth to Quantum GIS, the scale is not being projected properly and the area of a particular selected feature is not being calculated in the attribute table by ...
1
vote
2answers
181 views

Toggle editing option in plugins

I am working on python plugins for QGIS.I developed the plugins same as RT SQL LAYER plugins. When we draw the layers using query builder of "Add Postgis Layer" option,toggle editing option is ...
3
votes
2answers
408 views

Can Quantum GIS (QGIS) be used behind a paywall or barrier page?

The company I work for is a pay-for-subscription news website. Is it legal to use Quantum GIS (QGIS) to host maps that would be only available on our site to paying subscribers? I'm having trouble ...
5
votes
2answers
880 views

Garmin etrex 10 and QGIS

I want to know if anyone has been able to download data from a etrex 10/20/30 directly from Qgis. The usb protocol decsribe in a recent post does not do the trick. GpsBabel documentation states that ...
5
votes
1answer
1k views

fTools-Error: “…invalid geometry…”

I want to intersect contours with polygon like in the image below. But i got this error: Warnings: GEOS geoprocessing error: One or more input features have invalid geometry. Some output geometries ...
3
votes
1answer
499 views

How to create aux.xml file?

after starting to use MOBAC to create offline background maps I found the aux.xml files very useful as QGIS automatically sets the CRS so this would be very useful for my colleagues with smaller GIS ...
2
votes
3answers
893 views

Cut many lines with many polygons: Too much for my CPU/RAM?

I have a line-shp (80mb) and a polygon-shp (5mb) and want to intersect them. In result, the lines (contours) should be cut by the polygons. After using one of the tools "Vector -> Geoprocessing ...
10
votes
5answers
1k 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) ...
3
votes
1answer
1k views

Is there a way to prevent labels from being on top of everything else?

I'm having a problem in QGIS 1.7.4. The labels I have produced for one layer are overlapping an entirely different layer that has a higher precedence. This should not happen. Am I doing something ...
3
votes
1answer
3k views

How to filter features in a layer?

I am trying to display certain features in a shapefile-based layer using QGIS. I have found the subset function in the properties panel, which does exactly what i want, but is too tedious given that I ...
2
votes
1answer
616 views

QGIS adding or removing values in the style tab (layer properties)

I'm new to QGIS and have recently been testing the software as my org plan to migrate from ArcGIS to QGIS in the near future. I often use the 'Add values', 'Remove values' and the group values ...
8
votes
3answers
5k views

How to smooth/generalize a polygon in qgis

Is it possible to smooth or generalize a polygon in qgis? Ìs there a plugin available like the generalizer-plugin for lines? I could convert my polygons to lines, smooth them and convert them back to ...
6
votes
1answer
811 views

Is it possible to setup fiddler to capture requests from QGIS

I want to know if it is possible setup fiddler to capture WMS/WFS requests from QGIS and how to do it. Fiddler is capturing the requests from MapInfo and I don't remember making any setup in fiddler ...
1
vote
2answers
483 views

How to combine “positive” with “negative” polygons

I have 2 polygone classes (1 and 2). Inside the polygons are holes (white). Now I want to combine them with the polygon in witch the holes are. Understand? Sorry for that bad english... The white ...
4
votes
5answers
890 views

Elevation correction ASTER GDEM2 (+10m)

My ASTER GDEM2 has a average elevation error of -10m for my area. (I testet it using 90 defferential GPS reference points and compared it with old Topo25, SRTM, and GoogleMaps). I would like to ...
1
vote
1answer
176 views

QGIS - WGS84 to BC Albers reprojection no curved lines, any idea why? How to snap a line to a point?

I am trying to learn a bit about QGIS. So I thought I would drop in some layers of my Province and then recreate some points representing the BC Albers Central Meridian, and the two standard ...
2
votes
1answer
881 views

Projection ETRS89 (Ellipsoid: GRS80) 6-Degree Zone 33 to UTM33N - WGS84

Hi I'm having trouble to reproject a shape file in Qgis. The projection is supposed to be "ETRS89 (Ellipsoid: GRS80) 6-Degree Zone 33" and I would like to project it to UTM33N - WGS84 (EPSG 32633). ...
0
votes
0answers
63 views

How to turn off Google map data copyrighted window in Google Street layer (Qgis - Openlayers Plugin)? [duplicate]

Possible Duplicate: How to close watermarks in openlayers plugin After a few weeks not using Qgis, this morning I opened it up, accepted a request to update Openlayers Plugin. Right now, I ...
0
votes
2answers
4k views

Why won't QGIS recognize my GPS?

Garmin BaseCamp recognizes and receives data from my GPSmap 60CSx, but QGIS GPS Tools plugin does not. Am I missing a step? I want to be able to transfer data both directions. MacOS 10.6.8 QGIS ...
2
votes
2answers
195 views

Switch classes on/off within shapefile in QGIS 1.8

Hei! I got shapefile with 1800 points. They are classified by attribute in 10 classes. How can I display only 1 or 2 classes (like - switch on/off layer)? It seems quite usual function, but I ...
2
votes
0answers
200 views

Problem with geotiff in qgis only in some PCs

Helllo I'm having some weird problem opening a 16bits geotiff with qgis. In my pc it opens and displays perfectly, but in another pc (with the same version of qgis) it displays all wrong the image ...
2
votes
1answer
343 views

Does anyone know how to get the QGIS Web Client measure tool to show units in feet and miles?

Does anyone know how to change the QGIS Web Client measure tool (distance and area) so that it shows feet or miles rather than meters?
4
votes
1answer
825 views

Why are GeoJSON coordinates different exported from QGIS vs. ogr2ogr?

I have a shapefile with a Google Mercator projection (900913) that I need converted to GeoJSON. I need to do this on a regular basis amongst other things so I wrote a shell script to do it using ...
0
votes
0answers
24 views

Running QGIS on PC using XT (Desk top) [duplicate]

Possible Duplicate: How to fix QGIS error “Entry Point could not be located”? The error shown below occurs each time I try to run QGIS: The procedure entry point gtCPLError ...
1
vote
1answer
131 views

Projection - once again

I have a shape file with nature preservation areas (Biosphärenreservate) in Germany. I think the projection must be something like gauss-krüger zone 4 Pulkovo or something like that. When I reproject ...
6
votes
8answers
6k views

Splitting shapefile into separate shapefiles for each feature? [duplicate]

I have a polyline shapefile with about 20 kinds of roads. I would like to know how can I create automatically a vector file for each one. I can use ArcGIS for Desktop, QGIS (or GDAL separately).
26
votes
3answers
8k views

How to make a spatial view in PostGIS and add it as a layer in QGIS?

In PostGIS 2.0, what is the most efficient way to create a spatially enabled view that is viewable in QGIS? I followed the context of Part 2 of @Mike Toews answer to this question, and the view ...
-4
votes
2answers
194 views

What kind of map is this

I would like to have/create a map of Kazakhstan in the same way as in the attached picture (grey map of UK and Irland) using QGIS? I don't know what kind of map is this, what its name and where I can ...
4
votes
2answers
918 views

How to configure 3rd parties for the sextante plugin in qgis?

I'm currently exploring the enourmous potencial that the sextante plugin for qgis has to offer. The model builder will surelly be a very handy tool. The problem is I'm not beeing able to run 3rd ...
2
votes
2answers
486 views

Map Coordinates to Neighborhoods from MySQL Table

I have a MySQL database with a set of coordinates and a shape file (Zillow Neighborhood Database for Chicago) containing the boundaries for each neighborhood which I have converted to a spatial ...
7
votes
1answer
1k views

How can i create sectors for telecom towers

friends i am seeking advice from the GIS community I work in the Mobile networks industry and i took up a task to create a plugin for QGIS using c++/python that does the following: step 1: Create ...
1
vote
2answers
655 views

Convert classified raster map back into vector classes

I have this map (have whole country, this is just a sample, original map also contains color symbology for the value classes) and need to attach the values from it to points. I have no problem to ...
3
votes
1answer
774 views

Splitting lines at a specified distance

Does exist some plugin with it is possible to Splitting lines at a specified distance in Qgis?
2
votes
2answers
1k views

How to vectorize a Raster-Classification? (qgis, grass)

I classified my raster-DHM into elevation levels using colormap. Its not a "real" classification, just a colormap. So I cant vectorize the classes to get polygones for every class. Whats the best ...
3
votes
1answer
863 views

Get a pixel value

How can i do this operation: I want to get a pixel value fro the satellite image (Landat, GeoTIFF, 7 bands) using qgis-python. What operators should i use? (for example in qgis's Python Console) ...
3
votes
1answer
222 views

Looking for guidance with beginner use cases

Background I'm more or less completely new to GIS. At work we use a program called Microvision which does stuff like work out drive distance (in addition to straight line distance) from which you can ...
2
votes
2answers
360 views

How to import .dbf with long text values?

I'm trying to join a .dbf I made in LibreOffice with a shapefile. The .dbf contains ~10 columns, three of which have a large amount of text (~100 words). When I import the .dbf into QGIS, all ...
0
votes
0answers
48 views

How we add XY coordinates (in the attribut table) from shapefile (points) using QGIS? [duplicate]

Possible Duplicate: How to get the coordinates in Lat/long from a point layer? I created a new shape file and edited to add points at specific location. Now, I would like to extract the XY ...
10
votes
2answers
11k views

How can I join several raster files using QGIS?

I'm new to QGIS. How can I combine multiple raster layers into one layer? The raster images are of different areas with very little overlap. The goal is to bring numerous town plats into one project. ...
5
votes
1answer
234 views

How to visually join river to lake in QGIS?

I have two shapefiles, one is for landuse (which contains forests, and also lakes), and another one for rivers. When I set the both water types to have outlines, they are not joined nicely - they ...