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

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14
votes
3answers
362 views

Is it possible to use symbols instead of colours to visualise raster cell values?

I have a raster image (GeoTIFF) with integer values. I know how to visualise raster values in QGIS using colormaps or similar, but I would like to assign symbols to each colour value instead - just ...
1
vote
1answer
315 views

QGIS project on QGIS server — cannot load wms layer

I've created a qgis project on QGIS 1.8, copied it onto the QGIS Server, and am trying to load the project as a WMS Layer back into QGIS. There is one vector layer in the project. Paths have been set ...
7
votes
2answers
361 views

How to perform enhancement operations on an satellite imagery in QGIS?

I am a new user of QGIS please suggest how to perform image enhancement operations on an satellite imagery like ratioing, contrast stretching, edge engancement, filtering etc. in QGIS?
9
votes
3answers
2k views

How to programatically check for a mouse click in QGIS

I want to know how to check for a mouse click in QGIS. I am trying to write a python plugin and want to provide functionality similar to the "Select Single Feature" tool that already exists in QGIS. ...
1
vote
1answer
389 views

QGIS 1.8.0 - Define shapefile as UTM 15 NAD83 Feet

I have a shapefile which the .prj file says it is ...
5
votes
1answer
335 views

Why are points collected with a Trimble FM 750 off by more than a mile when displayed in QGIS?

I have a grower that has a FM 750 and is trying to make points in a field. When finished he takes the file out of the display and goes to his computer and he can bring up the points in the right ...
4
votes
1answer
277 views

How to fix incorrect coordinate data for the mouse's position

I am running Quantum GIS 1.8.0 on a 64-bit Windows platform. I've imported a data set that plots correctly when overlaid with a Google Satellite map, so I know that the layer/project CRS is okay ...
2
votes
2answers
119 views

QGIS on MAC cannot be opened because of an error

I know this question has been answered before, 3 months ago, but cannot work out how to join that thread. I have been using Mt Lion with QGIS successfully for some weeks but now get the 'Cannot be ...
7
votes
1answer
862 views

How to enable GRASS-modules in QGIS?

I have the latest QuantumGIS-1.9.0-master from Github with python-modules support and full GRASS-integration (GRASS-4.6.3-RC2) on Linux. When opening the GRASS-tools plugin, it only displays six ...
9
votes
1answer
306 views

Why are some columns not recognized as numeric even though I have a CSVT?

I have problems importing a .csv file. Some Values of the file are not supposed to be formated in text style, but in number style, thus i created an additional .csvt file like explained here. Both ...
5
votes
1answer
154 views

How to install the latest build of QGIS?

On Dec. 18, Radim Blazek developed the 'Improved raster singleband pseudocolor classification GUI'. Being new at QGIS, I have no idea how to go about updating to this version. Could someone possibly ...
3
votes
3answers
1k views

How to set up a Coverage Layer for Atlas Plugin?

Has anybody utilized the Atlas plugin? I am starting to take a look and setting it up on a project. My question is how do you set up the layer that is utilized for the coverage layer. Is there a way ...
1
vote
0answers
211 views

Can I Rotate SVG symbol counter clockwise in Quantum GIS? (Direction East 0 - counter clockwise) [closed]

I'm working in a road signs project. I need the signs layer symbol to rotate according to the value in the angle field, so they could be represented facing the correct orientation. However, the angle ...
4
votes
1answer
5k views

How to convert .dwg to shp uisng Quantum gis 1.7.0 [duplicate]

Possible Duplicate: How to import DWG in QGIS project? I have .dwg file and i need to covert to shp file using Quantum gis.Their is dxf to shp plugin I need .dwg file to shp file .How can i ...
5
votes
1answer
505 views

How to run custom queries on vector layers and display results?

Is there a way to display the result of a query in QGIS? For instance : To get the total number of inhabitants : SELECT SUM( inhabitants ) FROM countries To get the total density : SELECT ...
5
votes
1answer
260 views

Finding nodes with QGIS

As part of work in statistical mapping for school, I need to use QGIS to find the spatial extent of commercial nodes. A node is defined for this exercise as a zone of 75m in diameter where the ...
5
votes
2answers
162 views

How can I join a spreadsheet to a point layer?

I have a layer with point data for the grave positions in our cemetery. We are gathering data from each headstone. If I enter the data to a spreadsheet can I later associate the spreadsheet with the ...
8
votes
2answers
2k views

How to correctly install QGIS with plugins and GRASS-integration from source?

I'm running a Sabayon GNU/Linux (based on Gentoo) at my home desktop system and I want to install Quantum-GIS. I'm currently using the qgis-1.7.0-package from the repositories. But this is somehow ...
3
votes
1answer
209 views

How do I draw multiple copies of a rectangle in QGIS?

I am trying to create a map of our parish cemetery. I almost have a file with the centre point of each headstone plotted and now want to add a rectangle to each point to lay out the grave positions of ...
7
votes
1answer
380 views

How to rectify polygon shapes in QGIS?

I have some polygon-shapes in qgis-1.7.0 and want to ensure that every polygon is a rectangle. See image below. Is there any way I can do this in QGIS (or any other f/oss)? Or how can I improve my ...
11
votes
3answers
315 views

How to improve drawn shapes in Quantum-GIS?

I have a polygon-shape in qgis-1.7.0 and want to fix overlays and gaps between the edges of adjacent polygons. See image below. Is there any automated way to do this in quantum-gis? Or any other ...
3
votes
1answer
4k views

How to enable “snapping” in Quantum-GIS while drawing polygons?

I tried to draw polygons in qgis-1.7.0 and I somehow can't find or failed to find the "snapping" option. I'm used to ArcGIS-10.0 where you have some snapping options, like placing points of polygons ...
4
votes
2answers
1k views

How to Intersect between a vector (administrative areas) and a raster layer (slope)?

What I've got: 1: A vector-layer with administrative areas of my country 2: A raster-layer with the slope of the terrain of the same country (it is derived from SRTM elevation data with QGIS) What ...
0
votes
1answer
240 views

Which units are used for the Print Composer grid?

I changed the units on the general tab to inches. When I go to set up the grid under snapping, whats the units. From what I have read it seems as though they are map units, it that correct? I am a ...
9
votes
3answers
764 views

How to sum up values of neighbouring polygons?

I hope that you can help me with the following problem: I have a vector (polygon) layer. I would like to add an attribute to the layer that - for every polygon - sums the values of a specific field of ...
5
votes
1answer
970 views

How to transform a selected multipart feature into singlepart features while editing in QGIS?

There are several questions and respective answers for how to make a multipart features Layer into a singlepart features one using QGIS: How to break a single polygon into multiple polys? How to ...
2
votes
2answers
1k views

Is it possible to add a simple image or graphic to the map canvas?

Is it possible to add a simple image or graphic to the map canvas in QGIS (e.g. a symbol marker)?
1
vote
0answers
265 views

Quantum GIS SVG highway shields

I was following the instructions on how to create highway shields from the "Interstate Shield Styles in QGIS" post to create highway shields for a project I am currently working on. However, whenever ...
0
votes
1answer
369 views

Why is the imported TIFF file distorted with noise in Quantum-GIS?

I've a TIFF-file. Loading the raster image into QGIS does not display correctly. (Using the Add raster layer button.) It seems to be distorted with noise. See image below: The source of the TIFF ...
4
votes
2answers
433 views

QGIS saving analysis output as Postgis table

i am using QGIS and Postgis together. I can load data in Postgis and than i import it to QGIS. But i am trying to save an analysis output (example: buffer analysis, voronoi polygon or SEXTANTE ...
3
votes
1answer
2k views

DXF format for QGIS

I am trying to import some DWG files into QGIS. I am using ODA to convert the DWG files to DXF and then want to use the Dxf2Shp converter plugin in QGIS. The ODA converter has many options for the ...
0
votes
1answer
702 views

How to fix the QGIS for Android GPS panel?

I have installed qgis on my samsung galaxy s1. But I cant test the gps. I found how to turn the gps on, but I cannot open the gps pannel to do it. When i press view->panels there is nothing happens.
7
votes
3answers
302 views

INASAFE using US Census data? or similar QGIS hazard analysis - thresholding?

INASAFE seems like an interesting QGIS plugin but as I wade through the docs, I really need some sample data to play with in order for me to understand. There is a tutorial which uses Indonesia data, ...
0
votes
1answer
296 views

Looking for a tutorial on syncing QGIS with Trimble ProXT

Does anyone have any experience/advice to sync a TrimbleProXT gps antenna with the current "Lisboa" 1.8.0v? Additionally did you manage to collect features (points,line,polygons) in the field ok? ...
3
votes
1answer
281 views

How can i merge lines with same name and intersect each other?

I have shp file with 50k lines (roads). Many roads have same name like 'high road' . some of them are the same road (they intersect each other) and some are located in different places of the city. I ...
5
votes
1answer
690 views

How to change QGIS back to English?

When I booted up my windows machine this morning my menus had switch from English to what I think may be Russian and I can't read the menu options. I have tried unistalling, rebooting and then ...
3
votes
2answers
310 views

WMS layers don't draw in QGIS or ArcMap but do in OpenLayers

WMS Map was published by myself in AutoDesk Infrastructure Map Server 2013. I can connect and load detials (properties / metadata) in QGIS Browser, ArcCatelog. I can load the wms into QGIS desktop and ...
5
votes
1answer
572 views

How to force RGB in a raster in QGIS?

I have rasters in 1 band 64bits float that represent real data values and for which I can set min and max using the stretch to min and max option in QGIS. I would like to convert these rasters to RGB ...
0
votes
1answer
263 views

How do I repair NVIZ error: 'Can't find a usable init.tcl'?

How do I repair the following problem: The error occurred while I was trying to run NVIZ in the GRASS environment in QGIS. NVIZ however runs perfectly in GRASS. On checking the directories ...
1
vote
1answer
185 views

Is the GIS Repository In Ubuntu in a different stream than the main repository?

I was checking out this: https://wiki.ubuntu.com/UbuntuGIS and it outlines how to install PPA for GIS. I performed a basic apt-cache search on a few things and QGis and mapserver are available. Such ...
1
vote
3answers
1k views

Where is the QGIS Parallel Line Plugin?

Somehow I believe to recall there does exist some ind of "draw paralel line" plugin for QGIS. Could anyone please point me to - I cant find it :-/
1
vote
1answer
302 views

QGIS crashes when adding vector layer from mysql or testing connection to mysql

For a while I have been adding layers from my mySql database and all went well. Then I got crashes when adding new vector layers. Then I only got crashes and it is not possible to add layers from ...
3
votes
1answer
151 views

Why can't I edit polygons once they have been saved to MySQL?

I have a simple table with an id field and a polygon field in mySql. Using QGIS I can add new polygons and give them an id. Before saving them I can also edit them. But once a polygon has been saved ...
3
votes
2answers
357 views

Keeping package dependencies for QGIS master up-to-date

Not for the first time, QGIS has broken due to unsatisfied package dependencies. This is not surprising, as I'm using the 1.9 Master version which is released nightly, and the package dependencies ...
2
votes
1answer
77 views

remember QGIS instance

it would be absolutely great if someone could help me with the following problem: I have a simple Python-Plugin that starts another executable in a subprocess. From within this application (which ...
6
votes
1answer
200 views

How to consecutively number polygons from north to south following a polyline?

I have a shapefile (polygon) with a large number of polygons (roughly 10,000) that form a narrow but very long belt that windes through half a country and another shapefile (polyline) that represents ...
2
votes
1answer
256 views

How can I merge segments to one segment in QGIS (picture inside) and than get the center of each road?

I want to run a process that will make a table with lots of roads into distinct table of roads and than calculate the center of each road. How can I auto merge segments with same name to one long ...
3
votes
2answers
113 views

How to use geometry functions in rule based styling?

Edited: I'm trying to style some OSM data such that short fences, walls, etc just don't render. I only want to display barriers over some certain length. I've tried this rule, tags LIKE '%barrier%' ...
2
votes
1answer
134 views

Error when importing vector layer into GRASS

I am trying to import a vector layer into GRASS, but I keep receiving the same error. The values in the vector layer are important because I would like to use them to create a heatmap. What could I ...
3
votes
3answers
374 views

How to install the QGIS Statist plugin in Mac OS X?

I'm trying to install the Statist plugin. I'm running MacOSX 10.7.5. with Python 2.7.3. and Numpy 1.5.1. I have also installed matplotlib 1.1.0 (for python 2.7). When I try to install the Statist ...