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

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6
votes
1answer
1k 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
96 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
161 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
177 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
79 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
105 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
225 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
120 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
119 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
1k 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
46 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
222 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
198 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
183 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 ...
3
votes
1answer
87 views

Can I use predefined list of values from Postgis when I draw lines in QGIS?

Lets say that we have 2 tables in Postgis: Table 1 (PIPE): -ID -pipe_type_id -geometry Table 2 (PIPE_TYPE): -ID -type foreign key PIPE.pipe_type_id - PIPE_TYPE.ID Table PIPE is empty. Table ...
1
vote
1answer
321 views

Pie-Chart Coordinates in QGIS

I have a map of a region and I am plotting pie-charts (as diagrams) over every country in that region in QGIS (1.9.0). I also need to connect those pie-charts with lines (which I am creating in the ...
2
votes
1answer
94 views

Is there a way to add drop-down list of predefined variables to R-script menu in SEXTANTE QGIS?

I would like to create a drop-down list of variables (similar to what it is done for layers input) for my R script menu in SEXTANTE. Is it possible?
1
vote
1answer
417 views

Can QGIS read ESRI TIN file directly?

Can QGIS open directly a TIN file generated with ArcGIS?
4
votes
0answers
78 views

Is there a way to label a layer using its file name or layer name?

Is there a way to label a layer using its file name or layer name (if I'd change it in Layers window TOC)? I tried some functions but I'm not good on that. I have lots of shapes (lines) and it would ...
1
vote
1answer
288 views

OpenLayers Rendering Error [duplicate]

I'm using QGIS to render some air quality modelling results. I'm having issues with the OpenLayers Plugin whenever I have another vector layer active. The plugin works if it's the only layer in the ...
1
vote
1answer
118 views

Quantum GIS Standalone Browser

I don't think the QGIS standalone browser is working right on my computer. The only tab I can view is Param. The Metadata, preview and attributes tab are all grayed out. When I select a .shp for ...
0
votes
1answer
246 views

Convert / interpolate delimited text csv points grid to surface

I've got 12 delimited text csv files with regular pseudo-gridded points for temperature and salinity which look like this when zoomed in (inc distances) and this when zoomed out. I'm trying to convert ...
3
votes
1answer
107 views

How to extract coordinate pairs of crossing points of two polygons in PostGIS?

Extracting coordinate pairs of crossing points of two polygons in PostGIS Is it possible to extract x,y-coordinate pairs of crossing points of two overlapping polygons in PostGIS? Suppose there are ...
1
vote
2answers
133 views

Read raster value at mouse position

I have raster layer imported in QGIS. How can I read value of the variable represented by the raster at mouse position? I just have a new raster layer and I want to read values at random places to ...
2
votes
2answers
2k views

QGIS, Table Manager cannot rename column title

My current attribute table has a column whose title exceeds the ten letters maximum. I installed Table Manager, hoping I could rename the certain field to further use it (in order to add some ...
1
vote
2answers
462 views

How to search and move to feature in QGIS?

After solving how to search text string I need to move to the selected feature. Is it possible to do that?
0
votes
1answer
84 views

QGIS (Mis)Detecting Escape Characters in SLD files

Okay, I am just running into some trouble with the string literal functionality with QGIS's rule based styling. For example I have an attribute called LITH that equals 'BAS\b'. The rule where LITH = ...
0
votes
2answers
337 views

How do I successfully install the LecoS plug-in for QGIS 1.8

I have been trying to follow the instructions given here, but repeatedly get an error message pop-up titled "Mount" stating Access is Denied. Does anyone have a solution please?
1
vote
1answer
138 views

Image map plugin not working with point data QGIS

I have a point shapefile and I am trying to create a html image from it using the html image map plugin; however, I can not get it work. I get the error: Wrong geometry type Any ideas on this? ...
0
votes
1answer
1k views

How to install Sextante in QGIS 1.8 without Plugin Installer?

How can I install sextante (and where can I download it) if the Plugin Installer doesn't works? As I work for a corporation, I have some problems conecting to the official repository, and I cannot ...
0
votes
1answer
93 views

How to save 'No data value' to a QGIS layer style properties?

I have many raster tif files (100+) I found this link to the MultiQml plugin very helpful, from this post: Can I change properties of several layers simultaneously? However the 'No data' values does ...
1
vote
2answers
165 views

How do I gather X and Y co-ordinate data from a vector grid overlay in QGIS 1.8.0?

I have overlaid a 10m x 10m grid onto a UK Ordnance Survey raster map. I have set both raster and vector maps to the same CRS, (OSGB 1936 British National Grid; ESPG:27700). I have a csv file ...
1
vote
1answer
92 views

Ubuntu 'Manage plugins' in 1.9 (master) doesn't show 1.8 plugins

I'm using Qgis master on Windows 7 and more recently xubuntu 13.04. On xubuntu, the 'fetch python plugins' is missing, which Nathan just pointed out was intentional rather than a bug. My problem is ...
1
vote
2answers
433 views

Qgis - need to draw exact lines (mtrs) with fixed angle

I use GIS 1.8. I have the need to be able to draw exact lines and shapes on a bing map. (This is to project a yet to be build greenhous project on a map to show what i would look like). I have ...
2
votes
3answers
3k views

QGis: Merge intersecting polygons into one which are part of the same feature

I'm not a GIS professional so I hope I use the correct wording, at least I hope you understand my question. Let's say there are 5 polygons in the feature A. In the shape file there are more ...
1
vote
1answer
83 views

How do I prevent QGIS 1.8.0 changing my dbf table values when joining tables?

Im a newbie on GIS as well as QGIS. I have a table of data saved from Excel as dbf format. After dragging and dropping the file into QGIS and then opening the attribute table, all values less than 1 ...
5
votes
4answers
783 views

ArcGis Trace Tool for QGis?

is there any tool in quantum gis that traces a line like the trace tool (Editor Toolbar) in arcgis? I want to draw a line and trace this line back so that i get the beginning and the end of the line ...
1
vote
0answers
23 views

Creating a buffer based on area (i.e. sqm) instead of distance [duplicate]

Is there a way in ArcGIS 10.1 or QGIS (or any add-on) to create buffer based on an area (i.e. sqm) rather than using buffer distance? I'd like to create a buffer of let's say 5% of the area within the ...
7
votes
1answer
214 views

Is Python essential for working in QGIS?

I am a beginner in QGIS. I Generally have a doubt: to work in QGIS is it necessary to know Python? whether i am asking we should know to write python programs to make certain modules run?
2
votes
1answer
671 views

Fetch Python Plugins missing

I'm running QGis master v1.9.0 on xubuntu and the 'fetch python plugins' option is absent. This guy had this problem with vanilla 1.7.5 but fixed it by upgrading to 1.9.0 master. Nishant had this ...
4
votes
4answers
1k views

How to get vector data from OSM to use in QGIS?

How do I get data from OpenStreetMap which I can then edit in QGIS layer by layer? What is the best OSM output and what / how do I get to a suitable input for QGIS? OR...is there another appraach to ...
1
vote
1answer
142 views

QGIS Layers Not Lining Up

I am new to QGIS, I have been using ArcGIS for most of my maps. I have two layers that are not overlapping properly. One is a shp file from a GIS clearinghouse and another from a delimited text ...
1
vote
0answers
95 views

Is it possible to undertake spatial clustering with QGIS?

Is it possible to undertake spatial clustering with QGIS, and also end up with proportional symbols in a quasi 3-d symbology?
0
votes
1answer
2k views

How to search text string and select item in QGIS?

I have a table attribute with complete roads name. I have to search items by digiting a part of the road name and I need to colour all the items selected. eg: ROAD NAME: / road 01 / road 02 / road 11 ...
0
votes
1answer
70 views

Using an image file as a placemark in qgis

I am making a map of sports clubs in London. I have each club's crest as image files (tiff) and want to make the placemark symbol using these images. I know it's possible to upload images in the SVG ...
2
votes
1answer
209 views

QGIS and ArcGIS on the same PC

I work for a small non profit conservation organization and we have a reasonably high turnover of people... so it stands to reason that some people don't want to change from a preferred program. this ...
1
vote
1answer
73 views

Get the ID of polygon in edition sessions of QGIS?

I did a Qt custom form for QGIS which contain a QlineEdit that must get the ID of the current polygon in edit session. For example, I start edit sessions I draw 3 polygons when the Qt form is opened ...