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

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281 views

Rpy2 Unable to Load in Fresh QGIS Install

after installing qgis the a message given below is shown Unable to load the plugin: Unable to load required package rpy2. Please ensure that both R, and the corresponding version of Rpy2 are ...
2
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0answers
145 views

QGIS not rendering WMS layers

I'm a bit of newb' at GIS so be gentle with me. In Qgis I've set up a wms for the British Geological Survey: http://maps.bgs.ac.uk/ArcGIS/services/BGS_Detailed_Geology/MapServer/WMSServer? Now ...
4
votes
1answer
261 views

Personal shell launcher for PyQGIS

I have changed a shell launcher found at http://inasafe.linfiniti.com/html/id/developer-docs/platform_windows.html as to fit my wish: setting the system environment variables to be able to use PyQGIS ...
2
votes
0answers
211 views

WMS and Quantum GIS/ArcGIS

I periodically use a nice basemap served by the Utah state government in QGIS. Recently they upgraded their server from ArcGIS Server 9.3 to ArcGIS Server 10.1. Ever since then, I can't seem to get ...
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1answer
125 views

Can not import qgis.core in python

I installed OSGeo4W. I have no other Python version on my computer. I can import osgeo. But when I try to import qgis.core I am getting the error: >>> import qgis.core Traceback (most ...
6
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1answer
383 views

ISIS to GDAL to QGIS: Georeferencing Mars Images

I'm trying to use QGIS to view some images from the Mars Reconnaissance Orbiter Context Camera. I use ISIS3 to download the images and convert them to mapped .cub files, following the instructions ...
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0answers
58 views

How to delete a point with known coordinates in python?

I was wondering if there is a piece of code that does the opposite that setGeometry does and removes a point if there is one at x and y coordinates?
4
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3answers
600 views

Can OpenLayers layers in QGIS have transparency?

I often would like to set the basemap back by lowering the transparency. I would love to have this option in QGIS for OpenLayers layers, such as the stamen layers, google, etc. Is this possible? I ...
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134 views

How do I stop polygons from a .kml layer disappearing as I zoom in on the layer?

I am relatively new to GIS stuff and have a query about .kml files in QGIS. I have downloaded the .kml filefrom ...
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1answer
128 views

Modify 'Codepoint with Polygons' to add new fields

Sorry if this is a simple question - I'm just beginning in QGIS. I'm using OS Codepoint With Polygons data set which provides shape files of each Postcode area within the UK. Within each postcode ...
4
votes
1answer
301 views

How to measure the distance of multiple points to a line

I have two shapfile in QGIS to which I am trying to find the distances between. I have a shoreline which is a vector line and then I have hundreds of data points in the ocean. What I am trying to find ...
2
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0answers
275 views

Transform RGB-Map to CMYK (qgis, opensource tools)

I want to print a map I made with qgis. For the print I need CMYK-colors but the print-composers pdf-output is RGB. How can I convert the RGB-map/-pdf to CMYK?
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1answer
139 views

How to run “create mask” from the console?

There's a plugin called "create mask" for qGIS and trying out some simple scripting from the Python console. I would like to call it after I select the vector features I want, then do more related ...
6
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1answer
77 views

Is there a way to select only a certain polygon for editing?

I have a spatialite data base with 4300 polygons contained within. I wish to be able to edit the polygons but once i have highlighted the Polygon from the attributes table i find it hard to edit the ...
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0answers
57 views

Avoid rounding of coordinates in pyQgis

If I get the coordinates of a polygon in qgis by x = geom.asPolygon() It rounds off the coordinate from i.e. -27,200,334.86 to -2.72003e+07 How can I avoid that?
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2answers
140 views

loading CanVec directory full of .shp files

I'm totally new to QGIS, and trying to view a Canadian Topo map as published on an iMac - I don't want to change it. ...
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1answer
80 views

How do you Select an existing vector Layer and Edit it, using python?

I'm developing a small plugin that needs to be able to select a vector layer programatically based on what layer the user has selected. However I'm not sure how to do so. I believe I found the two ...
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3answers
140 views

QGIS Python Intro Text

After reading replies regarding starting a mapping business, I think I'd better read a Python book. Any intro-level Python books to recommend? Mila
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2answers
896 views

Total of attribute field of point layer per polygon layer

I have a polygon shapefile of many lakes, I also have a point shapefile of locations on those lakes where fish were caught. The point shapefile contains the attributes: Fisherman_iD, Fish_Caught, ...
2
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1answer
147 views

Setting coordinate systems in QGIS: “transform error caught”

I'm learning how to use QGIS (v 1.8.0 "Lisboa") on Mac OS 10.6.8. My goal is to create a simple county map of Illinois using the base data shapefiles available from the Illinois Natural Resources ...
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0answers
88 views

Why can I only see a default list of KML attributes in attribute table?

I converted a shapefile to kml using ogr2ogr. Glancing at the output, it looks correct -- it has a <Schema ...> and each <ExtendedData> references the schema (I uploaded a snippet here). ...
6
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3answers
399 views

How to Display Overlapping Lines?

I have multiple line layers that represent bus routes and many of the routes overlap (i.e. near terminals, transfer locations, etc.) Is there a function in Qgis which will display both features ...
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1answer
147 views

QGIS not Printing to PDF [closed]

Simple QGIS 1.8.0 not printing to PDF. Suddenly stopped. Is this an error or something. the resultant PDFs are blank pages. When i file print and use a pdf printer it creates blank docs. when i ...
3
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1answer
93 views

How to select features by matching attributes of two SHPs?

I have one line shape file with lot of road sections and a point shapefile, some of these points are outside my area of interest. The files have one attribute in common and I would like to do ...
2
votes
1answer
660 views

QGIS Zoom from python console

What are the commands to apply all types of zoom (full, on selected layer, etc.) in python console? I'm searching both on pyqgis cookbook and API documentantion, but I'm not finding anything ...
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1answer
254 views

Rasterize vector with gdal

"I would like to calculate the Euclidian distance from a residence to a public service of interest e.g. the distance from a residence to a green space (as the crow flies) in QGIS. After browsing the ...
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2answers
973 views

Extract coordinates from vector layer in PyQgis

In Qgis, I have made a polygon, and from that polygon I have made a vector grid via research tools-> vector grid. The grid covers the entire polygon. Now I want to extract these grid points in the ...
8
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1answer
491 views

How to create a Human Trafficking Heatmap in QGIS?

I'm trying to create a heatmap with about 325 points distributed around the city of Houston. (FYI Houston is a major human trafficking in the US: a title shared with LA and Atlanta depending upon ...
2
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0answers
159 views

How to use Memory layers in QGIS plugin to store results of Geoprocessing tools

I'm building a plugin to perform Multi Criteria Analysis (yes another one...). As part of my workflow intersecting vectorlayers is needed. I use QgsOverlayAnalyzer.intersection (a pity union is not ...
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1answer
143 views

Is the QGIS plugin repository broken?

I'm connected to the QGIS plugins repository, using QGIS 1.8.0 on Windows 8.... and although I can see a total of 119 available plugins, I can't see Sextante anywhere in the browser. I tried ...
5
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1answer
697 views

Does anyone know the proj4 Coordinte Reference System command line for Rectangular Polyconic Gores?

I am a GIS beginner using QGIS 1.8.0 I am trying to transform a world map from the standard WGS84 Coordinate Projection System to a set of rectangular polyconic gores, with a gore count of 12. ...
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1answer
221 views

how to find share segments between two shapes (line) using QGIS?

I have two line shapefiles. I want to find between them, where are located all share segments and extract the new selection shapefile. Can anybody help me? I am using Quantum Gis. I know that in ...
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375 views

z-Coordinate and interpolation plugin in QGis

I've a csv file that includes weather stations locations (x,y,z) and precipitation values. I loaded the file by using add delimited text and then converted it into a point shapefile WS84. By using the ...
4
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1answer
679 views

How to customize label color in QGIS: Data defined label settings? Expressions? Both? What are the steps? [duplicate]

Updated to show more current screenshot and clarified the question (Which tools? What are the steps?) I'm learning QGIS (1.8 "Lisboa" for Mac). On the QGIS Layer labeling Settings window there is a ...
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3answers
1k views

How to create lines between pairs of two coordinates?

I have a table with pairs of points. Out of that I want to create a line layer (that keeps all attributes of the table). One line for each raw from point to point. I want to calculate the length of ...
2
votes
1answer
249 views

Why are JPG files invisible in Georeferencer?

I want to georeference a jpg file (map) with QGIS 1.8.0 on a Windows 7 (64 bit) machine. The georeference window opens, but the map is not visible. When converting the jpg file into a tif file (e.g. ...
6
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2answers
796 views

Tilemill Dynamic Tile Generation

I have recently used Tilemill and I wish to implement it for dynamic tile rendering.As I've seen an CartoDB doing in cloud system,they can query & generate dynamic tile for request with UTFGrid. ...
2
votes
1answer
89 views

Where can I get a comprehensive list of Rules expression operators?

I'm selecting and styling my points layer on a contour map of Philadelphia using Rules Based Styling. (see: Can I use rules based rendering in QGIS to select features?). The filtering process using ...
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1answer
100 views

How Could I Calculate Shortest Path ?

I am working on QGIS - 1.8 Version and frequently getting an error while using Road Graph and Shortest Path Opetions. Kindly Suggest or provide solution.. With Regards Prashant Persai
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2answers
115 views

Generating new shp files according to attribute in QGIS

I know that it is possible to color a vector map by attribute. I separated a map into 4 colors based on an attribute and now I want to generate a new map for each color. Is there a way to do this in ...
3
votes
1answer
309 views

How to make survey lines within polygon?

I am trying to figure out how to make survey lines within a polygon. So first I make a polygon. Now I need to fill this polygon with lines, where I can choose the spacing between the lines, and the ...
2
votes
1answer
52 views

QGIS VPAT; Section 1194.21(c)

I am attempting to fill out a VPAT for QGIS so that it can be made more accessible in the federal IT environment. I could use some help and wanted to explore this venue as a means of getting it. If ...
2
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0answers
33 views

Automatic insert of project name into database

For every layer I've a field in my postGIS database that should be filled with the name of the current project and today I do this manually. Is there a way to do this with the Commands that can be ...
14
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2answers
1k views

Creating Thiessen (Voronoi) polygons using lines (rather than points) as the input features?

I have a set of line features inside a particular polygonal boundary. For each line, I'd like to generate a polygon inside which every possible point is closer to the given line than to any other line ...
1
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1answer
267 views

QGIS Sextante Python UnicodeEncodeError

I have some issues with Quantum Gis 1.8. When I try to use shapes to grid (sextante-saga tool) I get the following error (comes up when I try to define the new grid file name): Fehler bei der ...
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2answers
209 views

How to mask out features outside of the Coverage Layer for Atlas plugin? [duplicate]

Using the Atlas plugin for qGIS how do I set the coverage so that it will only highlight the feature(s) I want but still show the surrounding features as grayed out areas? This would have been easy ...
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0answers
293 views

Lines as Great circles on a map

How can I get line features to appear as great circles on a map, instead of straight lines? Thanks,
2
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1answer
85 views

QGIS mixing up CRS

I´ve just started working with QuantumGIS for my thesis. I ordered shapefiles with the CRS: ETRS 89 UTM Zone 33N, but QGis layer properties now shows the layer has a different CRS (namely SWERE99 TM) ...
4
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2answers
657 views

QuantumGIS 1.8: how to define bounding box within Add WFS Layer dialog

I use QGIS 1.8 under WIN XP in Standalone Installer Version. I need to limit the extent of the data to be downloaded via WFS because of the large amount of data in the requested layer. In ...
2
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0answers
60 views

QSpatiaLite: Cannot create table

I am running QGIS 1.8 (SpatiaLite 3.0.1) and QSpatiaLite 6.0.1. I have a spatial table EventPrecise (with geometry column p in EPSG:4326). I want to join this table with another, non-spatial table ...