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

learn more… | top users | synonyms (1)

0
votes
1answer
99 views

Custom forms and location of python code

I'm working with custom forms for the attribute table of various qgis-object and it works realy well, but I would like to have my forms and their python files separated from the projects. This is not ...
2
votes
2answers
991 views

Percentage of polygon in one shapefile within polygon of another

I'm a newbie, apologies if this is obvious/has already been asked and answered but I couldn't find anything. I have two shapefiles: 1. an administrative boundary layer for a county in the UK known as ...
0
votes
0answers
72 views

QGIS: “No data” raster value for missing rows conflicts with data?

I’m having a problem with specifying “no data” in a raster dataset in QGIS 1.8.0-Lisboa. QGIS does fine in interpreting pixels I don’t have rows for as “no data” if I set Layer Properties -> ...
1
vote
0answers
192 views

Install QGIS 1.9 on Fedora 19

I have tried the guide http://hub.qgis.org/projects/quantum-gis/wiki/Download yum install --enablerepo=updates-testing qgis qgis-python qgis-grass qgis-mapserver it shows only QGIS 1.8 is ...
2
votes
1answer
66 views

After joining data from csv file to shapefile, why are all values zero in categorized renderer?

I have joined data from a csv file to my shapefile. The attribute table shows a successful join. I have converted the variable of interest to INTEGER. But when I go through Style to categorize the ...
0
votes
2answers
107 views

How can I see average of raster value over certain area, marked by mouse?

I have a raster in Quantum GIS and I am just exploring it. How can I see average of raster value over certain area, marked by mouse? In other words: How can I select particular area in QGIS? How can ...
0
votes
0answers
60 views

Unwanted lines when cutting & merging polygons

I am using QGIS version 1.8.0. Sometimes when I cut or merge polygons I get unwanted lines left in them. On zooming in to them they do not appear to be slivers. Is there a way of getting rid of these ...
1
vote
0answers
425 views

Check if a point is near a linestring with MySQL Spatial Extension (untrustable)

I have to discover if a given point is at least 500 meters (ou other distance) from a route line that exist in my database recorded using the MySQL Spatial. I see there is no similar function in ...
1
vote
1answer
306 views

export openlayers as .shp file in Qgis

Is it possible to save an openlayers map as a shape or tab file in Qgis. I would like to have a part of an area from google maps as a shape file for later use?
1
vote
0answers
235 views

Styles from Geomedia (mdb with style library) to be used in qgis?

We are trying to move some projects from Geomedia Professional to QGIS. Since we have large style libraries (stored as mdb) we are looking for a way to convert the styles to a format that QGIS can ...
1
vote
3answers
1k views

How can I translate Modis HDF To GeoTiff

I've a MODIS04 L2, and I want to extract band 8:Image_Optical_Depth_Land_And_Ocean. I use Quantum GIS to open this band, because Quantum GIS see this is not coordinates so this allow me to select ...
1
vote
1answer
63 views

Why are attributes missing in overlay tab QGIS 1.8.0?

I want to add a diagram overlay onto a shapefile layer. When I look at the attribute table, all the correct columns are shown. However, when I open the layer property box, the attribute columns I want ...
1
vote
1answer
147 views

Sum of point attributes inside hexagons using QgiS UI

I'm very new to Qgis so I would very much appreciate any help you can give me. I have a point shapefile that corresponds to locations of animals captured. I've joined a table to this shapefile with ...
2
votes
1answer
666 views

How to zoom to a selected feature with pyQGIS

I want to create a function that selects a feature and zooms to it (similar in QGIS). Therefore there is following function: QgsMapLayerRegistry.instance().addMapLayer(self.vlayer) def zoomTo(self): ...
1
vote
2answers
394 views

How to develop a Canopy Height Model of LIDAR data in QGIS?

I am having a DTM and DSM files .I want to develope a Canopy Height Model in Qgis is it possible?
0
votes
1answer
68 views

How can I know the number of polygons in a selected area in QGIS

How can I know the number of polygons in a selected area in QGIS? Can I use the Select features tool? How can I use? Thank you
0
votes
1answer
543 views

How to read attributes in pyQGIS and QGIS 1.8 without setSelectedFeature

I add a vector layer to a map with QgsMapLayerRegistry.instance().addMapLayer(self.vlayer) later the attributes are read with def select_all(layer): layer.select([]) ...
1
vote
1answer
823 views

Where are the 3d analyst tools available in QGIS?

I want to know whether we can perform 3d analyst in Q-Gis? If yes, means where is that option present?
5
votes
1answer
190 views

Which GIS Software is Right for small manufacturing trends analysis?

I'm a graphic designer who has been tasked with choosing a mapping platform for the manufacturing company I work for. One of my colleagues began our project by using a trial version of ArcGIS to ...
4
votes
2answers
933 views

What dissolve tool in QGIS allows me to summarize statistics for multiple attributes?

Is there a tool or plugin in QGIS that resembles ArcGIS 10's Dissolve tool? I'm trying to dissolve several polygons (parks) around the boundaries of another layer of polygons (cities), while ...
1
vote
2answers
220 views

Stop rounding values in Qgis attribute table

I am calculating the areas of my polygons in Qgis using $area and everything works fine until I click on "save". All my values are rounded to an integer. I tired setting the output field type to ...
1
vote
1answer
235 views

How to compute area for polygons in an EPSG:4326 shapefile?

I have a shapefile covering the whole globe, in EPSG:4326 (geodetic WGS84). I would need to compute the polygons areas in a metric such as km2. How can I do that in QGIS or with gdal/ogr and having a ...
4
votes
1answer
672 views

How to get SAGA working with QGIS Sextante?

I just created my account on this forum to find an answer to a stupid (?) problem I can't deal with. First, let's precise I just (some months ago) learned on my own what GIS was, and gave it a try ...
0
votes
0answers
197 views

Point in polygon analysis fails with “TypeError: arguments did not match any overloaded call”

I am using QGIS 1.8 on Windows 7 I want to perform a point in polygon analysis using the Vector > Analysis Tools menu. My point layer is the result of a SpatiaLite query which returns 10'000 points. ...
3
votes
1answer
777 views

How to add CSV data with no coordinates to a polygon layer in QGIS?

I would like to add attributes from an spss database (around 300 cases) to a polygon layer in QGIS. Both datasets have a column with unique IDs. I exported the spss data to a CSV file which does not ...
1
vote
0answers
59 views

QGis overlap labels

I have a csv file imported into QGis 1.8 and this layer is receiving real time data.Into this attribute table layer there is a field which values i use to label it but overlapping all values when ...
1
vote
2answers
92 views

How do I adjust transparency on heatmap so that I can see background raster map? QGIS 1.8.0

I have created a raster heatmap for the first time, but I cant seem to adjust the transparency settings to let me see another background OS raster map beneath it. I have attempted to swap the ...
2
votes
1answer
114 views

Creating pop-ups on point layers

i have a postgresql database which is refreshed all 10 minutes and i need to create graphs in pop-up with the data. When i click, a pop-up (or annotation ?) appears. How can i make it possible ? ...
1
vote
0answers
62 views

Coxcomb chart in qgis

I would like to use special pie chart for my map, where the angle is not important, but area or radius of the arc carries information. I found, that this type of pie chart is calling ...
0
votes
1answer
404 views

How to use a database in Qgis

What is the primary use of database in Q-Gis? How to connect to a database in Qgis?
0
votes
1answer
270 views

convert shapefiles to cad files

hi i'm having a difficulty in converting shapefiles to cad file. i'm currently using the ArcGIS 9.3.1 version and i tried to convert it using the toolbox>conversion tool>to cad>export to cad....the ...
3
votes
1answer
432 views

How to add complex Emergency Symbology (TrueType fonts) to QGIS?

In other packages I would simply ensure the TrueType font (+.ttf) was loaded on the operating system and it would be available for use. QGIS seems to rely on making your own. The symbols I wish to ...
0
votes
1answer
83 views

Can this compilation and display of species frequency data be improved? QGIS 1.8.0

As a newbie on QGIS, I would like to find out if the way I put a species frequency map together could be improved upon. I had to map the presence or absence of 7 plant species surveyed in 30 2m x 2m ...
6
votes
1answer
983 views

Identify polygon overlaps within single shapefile

Using either QGIS (1.9) or ArcInfo (9.3.1) I'm trying to identify unique overlaps of prehistoric building footprints from an archaeological site recorded within a single polygon shapefile. While the ...
1
vote
2answers
94 views

Why can't I save csv as a shapefile

I am trying to follow the instructions given here, Tutorial: Making Heatmaps using QGIS and GRASS , to build a heat map with my own data. I taken the first step and imported a csv data table into the ...
0
votes
4answers
160 views

How can I calculate different polygons by different attributes?

I'm doing my master thesis and want to calculate different polygons (in QGIS 1.8 for Mac) in four different columns which I defined by different attributes. i.e. some of the attributes in the first ...
0
votes
1answer
165 views

Compile Qgis source : Links errors (Windows)

I am actually trying to compile the source of the qgis git : https://github.com/qgis/Quantum-GIS In order to compile it, I follow the steps of the tutorial here : http://www.qgis.org/api/INSTALL.html ...
1
vote
0answers
91 views

How to spatial join points attributes to layer with two (or more) overlapping buffers in QGIS?

I'm working with QGIS 1.8 and I've got 3 layers : 2 points layers, and 1 layer composed of the buffers of one of the points layer. I'd like to retrieve the informations, for the point layer that ...
0
votes
0answers
78 views

Why is it that QGIS shows only one attribute table on all layers?

I have checked the "Select Single Feature" before clicking the Attribute Table but even if I choose a different layer, only one attribute table is shown.
3
votes
1answer
101 views

How do I make line symbols intersect cleanly without showing edges in QGIS?

I digitised a map showing electric grid lines. I merged a number of lines into a single feature. Now, I'd like these lines to be displayed so that the intersections appear continuous. At the moment, ...
1
vote
1answer
219 views

How to create “two-dimensional” color ramps in QGIS?

Is there a way in QGIS to create a "two-dimensional" color ramp for the graduated symbology; i.e. a color ramp that determines a color based on two different attributes? My situation is that I want to ...
0
votes
1answer
118 views

Cannot import Grass in Console of Qgis (1.9.0 Master)

I can't import Grass in Console of Qgis (1.9.0 Master). I am guessing it is because of some Grass environment variables which are not set up correctly. However I don't understand why it is working ...
3
votes
1answer
117 views

Is there a way to create a plugin in C++ without compiling all the Qgis source?

This is my second post and I apologize if it's post the same day on the first. After several researchs, I found the only way to create a plugin in C++ is to compile the Qgis source with the plugin ...
2
votes
1answer
3k views

make: pyuic4: command not found

I need to develop a QGIS plugin for a project. First, I launched the following command for the installation on Ubuntu 12.04: sudo apt-get update sudo apt-get install qgis sudo apt-get install ...
7
votes
2answers
968 views

projection change to create buffer in QGIS

I am about to become desperate... I like to create buffer around several points - if possible - with a declaration of the size in km of these buffers. Just to show you what I am working with: My ...
0
votes
1answer
45 views

Compile a plugin in 1.9 Qgis-dev

I am actually learning qgis and how to devellop a plugin. I have to write this plugin in C++ and not python because people coding in C++ want to modify it after. I have found some plugins in the git ...
1
vote
1answer
219 views

Career advice in Gis field [closed]

I am a B.Tech graduate(2013) in Geo Informatics and Geo Technology.Presently, i am working i an company as Junoir Executive in Gis . I also know some programming languages like "V.B.net" and C#.My ...
0
votes
0answers
30 views

how to divide a Area shapefile into multiple segment, so that each segment will be a seperate feature in attribute table? [duplicate]

I'm very new to GIS, I'm using QGIS and here's what I want to do: I have a shapefile of an area . I want to divide that area into multiple segment (not grid), so that each segment will be a ...
3
votes
1answer
191 views

What's the projection of this albanian military map?

I've received some very useful maps of Albania for my work (scale 1:25000) and I would like to georeference them in order to put them together to one Map for my destined regions. Unfortunately I ...
1
vote
2answers
178 views

Measurements across UTM zones, how to apply spatial parameters to a customize a projection?

I have a survey grid that spans 3 UTM zones. Using http://www.epsg-registry.org/ I can get an indication of what projections are available. Where can I find more info on the patterns of distortion ...