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

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4
votes
3answers
1k views

How do I add (and map) a non-spatial table to QGIS from SQLite?

I have an sqlite file from my Wigle Android app (wiglewifi.sqlite). It's not a spatial file, just tables with lat/lon and other data. I can add spatialite layers just fine, but cannot seem to find a ...
2
votes
1answer
826 views

JOSM vs QGIS/uDIG for road network editing and storage

My application needs to store a road network and provide editing functionality for that network (editing/updating/removing lanes, signs, traffic lights, speed limits info, etc.). I find JOSM tool to ...
1
vote
1answer
739 views

How do PostGIS layers in QGIS work?

I use QGIS 1.4.0 to import a layer which is basically a road network converted from an .osm file to a PostGIS database table by osm2pgrouting. I have skimmed through the documentation, but I am still ...
2
votes
2answers
5k views

Viewing .las format LIDAR data in QGIS?

Is there an easy path to visualizing this LIDAR data? I have QGIS, and some USGS LIDAR data in (.las) format downloaded from http://lidar.cr.usgs.gov/ . This means I have both the (.las) and ...
2
votes
1answer
378 views

A software architecture for viewing/editing roads and routes

I have a routing software module which uses PostGIS/pgRouting to calculate routes. The road network is generated from an .osm file with osm2pgrouting tool. I need to enhance the functionality of the ...
7
votes
3answers
3k views

How to delete multiple selected polygons at once?

I'm new at this, a novice at best. I'm using QGIS 1.7.3. I simply want to select a large number of polygons on screen and hit the delete key to delete them and resave the shapefile. Can this be done?
5
votes
3answers
4k views

How to add Raster legends in QGIS map composer?

Is there a plugin or method to add legends for raster layers (with a custom colourmap) as an item in the print composer?
1
vote
1answer
6k views

Python :ImportError: DLL load failed: The specified module could not be found

I am working on Python plugins for QGIS. I set my variables as PATH :=C:\OSGeo4W\apps\qgis;%PATH% PYTHONPATH:=C:\OSGeo4W\apps\qgis\python But when I try to run my .py file in IDLE I get an error ...
2
votes
2answers
455 views

QGIS 1.7.3 and pyqt4 version mismatch

I installed QGIS 1.7.3 using OSGeo4W installer.I have python 2.7 and pyqt4-py2.7 installed on my system.My system paths are: ...
9
votes
6answers
7k views

How to join lines in QGIS?

In QGIS, I have two lines. The endpoints are near each other, but not quite aligned. I'd like to turn the two lines into one, with the two endpoints merged into midpoints. The closest I've been able ...
14
votes
1answer
722 views

Monte Carlo simulation using QGIS and pgRouting on optimal sidewalk construction

I am new to spatial analysis and would appreciate some general direction on a project I am attempting, outlined below (I am starting from scratch). GOAL: To find the best locations to install 2000 ...
0
votes
1answer
754 views

libmysql.dll-procedure entry point error [duplicate]

Possible Duplicate: How to fix QGIS error “Entry Point could not be located”? I am working with qgis,pyqt4 and python2.5. I was getting error qtcore4.dll could not be located.so ...
2
votes
1answer
299 views

How to import selected features from QGIS to PostGIS?

I am trying to import selected features from Quantum GIS to postgresql directly. I do not know how to do it. Actually, my problem is, I have full country road network. But, I need to cut road network ...
1
vote
1answer
9k views

How to fix Qtcore4.dll can't find procedure entry point? [duplicate]

Possible Duplicate: How to fix QGIS error “Entry Point could not be located”? I am working with QGIS, python2.5 and pyqt4 for py2.5. My system variables are as follows: ...
3
votes
2answers
1k views

How to fix for the GDAL clipper tool in QGIS?

I would like to clip a DEM with an admin boundary using qgis, in order to calculate a measure of variation. However, when I use the Raster clipper tools and select mask, I get the error message: "An ...
1
vote
1answer
99 views

Render a raster with hue values in QGIS

I have a single-band raster (a GeoTIFF) with hue values in the band. I'd like to render it, preferably in QGIS but another open-source GIS would be acceptable as well. The saturation and value should ...
3
votes
2answers
1k views

How to reproject from Michigan Georef to WGS84 in QGIS?

I am trying to reproject a michigan state land shapefile which is the NAD83/ Michigan Oblique Mercator EPSG:3078 to the WPG84 EPSG:4326 projection. However when i try to do this my map gets squished ...
19
votes
3answers
4k views

Optimal video cards for GIS programs

I recently purchased a Dell XPS-8300 (i7-2600|16 GB DDR3 RAM|64-bit Windows7) which I intend to use primarily for GIS programs. I bought a refurbished model because it was much cheaper and because I ...
13
votes
3answers
4k views

Is there a way to render lines with a smooth (bezier) curves in QGIS?

I am moving from creating maps with Illustrator to making them with QGIS and actual data. One of the things I haven't been able to re-create in QGIS are the smooth curved lines I can get in ...
9
votes
2answers
1k 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 ...
5
votes
1answer
1k views

How to use QGIS Time Manager sample data?

I've downloaded the Time Manager plugin for QGIS for Windows, version 1.7.1. I'm not sure whether I should really be asking a question on here, but since there doesn't seem to be an issue tracker on ...
9
votes
2answers
696 views

How to Create Two Color Lines in QGIS?

I've been working on making mountain biking and hiking maps using Illustrator and I am now trying to move to QGIS so there's real GIS data powering the maps, making updating/scaling them easier than ...
6
votes
2answers
5k views

How to create a new layer from overlap between two layers?

I'm new to desktop GIS, and will try to ask while lacking the proper terms from the GIS lingo: If QGIS was like Photoshop I would like to make a selection from one layer, and then match that ...
2
votes
1answer
1k views

Quantum GIS Reproject a projected coordinate system with rotation

I have two shapefiles:- one in WGS84 Z30S and one in a custom, system based, projection. I need to convert the custom projection into WGS84 Z30S. I have a set of parameters including a shift in X and ...
2
votes
1answer
111 views

Does QGIS support MT83F

Does QGIS support NAD83 Montana State Plane Zone, US Foot? I have vector data in a CSV file that I would like to display, but the coordinate system is MT83F. I don't see a matching CRS. Is there a ...
1
vote
1answer
220 views

Quantum GIS Standalone Installer Windows folder

I have a very simple question for you: what is the "Quantum GIS Standalone Installer Windows" folder? Is it, as usual, something like "c:\program files\quantum gis"? I cannot make a test (at this ...
11
votes
4answers
2k views

How to connect lines in a network?

I have a shapefile of lines and another of polygons. When two or more lines intersect a polygon they should be connected (snapped), but sometimes during manual digitization this doesn't occur. I need ...
10
votes
5answers
563 views

Database versus Files for Solo Developer

I'm just getting started in GIS and am interested in using it to create maps of mountain biking trails in my area and nearby. I've been learning QGIS and have made enough progress to generate a decent ...
1
vote
2answers
588 views

Is there any known reason for QGIS recurrently crashing in windows7?

I use (and been a big fan of) QGIS daily for 7 months now, and only recently - past couple weeks - been experiencing problems with QGIS recurrently crashing. This is even more serius cause it happens ...
2
votes
1answer
1k views

QGIS [500]INTERNAL SERVER ERROR

My Name is Daniel and I'm from Indonesia. Short story recently I was learning how to set up qgis server. So here's the trouble I've encountered so far: I was using OSGEO Live 5 Distribution ISO' ...
1
vote
3answers
2k 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
499 views

How to refresh QgsMapcanvas?

I am using Qgis 1.7 and I want to refresh the mapcanvas so I am using refresh() function of QgsMapcanvas class and Nothing is happening to the Map Canvas. I am using Python for customizing
4
votes
1answer
2k views

Loading a raster using QGIS into a PostGIS2.0 enabled database

Following on from my attempt to install a postgresql 9.1 db with postgis 2.0 on windows 7, I am trying to figure out how to load a raster. I have successfully loaded a shapefile, and am trying to do ...
12
votes
5answers
7k views

Is it possible to make a DEM from contours in QGIS?

Is it possible to make a DEM from contours in QGIS? I have a shp file (contours) and their heights, can I use QGIS for produce a DEM without using GRASS? I find this creating a dem from contours but ...
4
votes
3answers
2k views

How do you open/display and extract NetCDF files info?

I am working with NetCDF files using R & Matlab and I would like to know if the GIS community is using them. I know that ArcGIS can open & display, however most of the times the results are ...
5
votes
1answer
384 views

Is there any plugin for QGIS to calibrate contrast and brightness of a raster layer?

I frequently need to deal with the contrast and brightness of raster layers in QGIS and I miss the tools in ArcGIS for this task. Should there be a plugin already developed for QGIS? If there is, ...
0
votes
1answer
2k views

How to set up QGIS + georeferencer for easiest georeferencing

The goal is to make converting scanned paper maps to map tiles as easy as possible. I've done a few, but the slow part is manually entering coordinates of points. What I'd like to do is for each ...
3
votes
1answer
4k views

Changing the coordinate system of a qgis layer to the projection of Google Earth

I want to know how to change coordinate value of a vector layer (13293061,-572595) to 119.413,-5.13677 (vector data & Google Earth do not match). If I output my data using Google Earth as ...
1
vote
2answers
696 views

Can you reorder a classified vector layer in QGis?

I have a GML file that I'm displaying in QGis - it contains a set of contours and they are written out in such a way that the lowest contour (largest polygon) is drawn last thus covering up all the ...
11
votes
5answers
6k views

How to perform Raster Reclassification in QGIS?

Is there a way to do reclassify a raster image to Qgis? In Arcgis you can do that in Spatial analyst Tools→Reclass→Reclassify Any ideas?
3
votes
2answers
6k views

Manipulate .asc files in qgis

I have an .asc file and I want to import in QGIS. The standard way to open it is from "add Raster layer" ("import Raster Layer"), there is another way? I know is strange that ask but I need it. And I ...
3
votes
1answer
2k views

Why does the QGIS Server WMS layer not load in QGIS Desktop?

I have created a .QGS file with one PostGIS layer which is the alaska.shp file that comes from the samples. It was loaded via the shp2pgsql utility. When looking at my qgs project referencing the ...
1
vote
2answers
1k views

How to load NASA JPL WMS Global Mosaic into QGIS

I was playing around with uDIG and realized that its WMS capabilities are awesome! The Global Mosaic perfectly fits a map I created! However, I was planning to use the WMS layer as an orientation for ...
5
votes
2answers
376 views

Is it possible to use the Goode Homolosine projection in QGIS?

Is it possible to use the Goode Homolosine projection in QGIS? Both QGIS and GRASS seem to have trouble with the interruptions, squashing the higher latitudes together. I tried +proj=goode ...
3
votes
2answers
2k views

How to import a non-spatial Table into QGIS?

Can I import tabular data in Qgis, without any information about X and Y only the table? I need to join them after importing them.
2
votes
1answer
581 views

Does QGIS support parsing of date strings in tables?

It is straightforward to load GPX files (GPS downloaded tracks / points) into QGIS, then save and manipulate them as shapefiles. However, the recording date (in the comment (cmt) field) of waypoints ...
11
votes
1answer
654 views

Method to shade or overlay a raster map to reflect time of day and ambient light

I have a daytime raster of my study area. I have 20+ counters in the study area that count "stuff" with a timestamp. Using PyEphem I determined the type of ambient light for each collected data ...
1
vote
0answers
159 views

Can I overlay layers in Dealul Piscului 1970 and WGS84 in QGIS?

I have a 10 Gb ECW file (mosaic of a whole county) that is in Oblique Stereographic projection with Datum: Dealul Piscului 1970. The problem was that no matter the Default CRS for new project was, ...
7
votes
2answers
850 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 ...
4
votes
2answers
455 views

How to fix a raster with wrong Eastings?

I get an error when trying to warp a tif file in QGIS: ERROR 1: Too many points (35721 out of 35721) failed to transform, unable to compute output bounds. I am using QGIS 1.7.0 Wroclaw with gdal ...