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

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3
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134 views

Can you set a QGIS print composer to render the map as default?

I have set up a number of templates for the print composer in QGIS. In the Print Composer, there is the option to have the map image displayed in 3 ways: as a blank rectangle with no updates until ...
3
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88 views

Can layers from Spatialite db be used as input for a Sextante model?

I'm trying to build my first models in SEXTANTE and already fail at the start. It seems not to be possible to add a vector layer which derives from a database. Orginally, the layers are from a .mdb. I ...
3
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125 views

draw lines with an angle inside a rectangle in python

I am trying to make a plugin for Qgis with python. I have the four corner coordinates for a rectangle. I want to give the user the inputs, line space and angle (0 -180 degrees). With these inputs, I ...
3
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0answers
86 views

Is there a tool for automated quality assurance for vector data captured on raster data?

I wonder whether is any tool(or script) in ArcGIS or QGIS which allows to make an automated quality assurance for vector data captured on raster data? vector data on binary raster:
3
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0answers
116 views

How does Zonal statistics handle pixels that are on the border of the polygon?

I am using the plugin zonal statistics to calculate the sum of the raster cells within polygons. How does this plugin handle pixels that are on the border of the polygon, are those cell values ...
3
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147 views

How to achieve better Dissolve results?

I applied the Vector>Geoverarbeitungswerkzeuge>Auflösen (Dissolve) on a zoning plan (see picture zoning plan). I used the attribute village name as the dissolving criteria. The resulting geometry for ...
3
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239 views

Building Qgis-1.8 on Scientific Linux - a sip error occured

I'm on Scientific Linux 6.3 and after trying to build Qgis 1.8 fter "ccmake" I got the error: [ 89%] Built target translations [ 89%] Generating analysis/sipanalysispart0.cpp, ...
3
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69 views

Can QGIS give GeoJSON layers a meaningful default name?

When I add a GeoJSON layer to my QGIS project, it always gets the name OGRGeoJSON. This is in contrast with shapefile layers, which seem to be named after the file name by default. Is there a way to ...
3
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109 views

Why doesn't Polygonizer copy the line ids to my polygonized shapefile?

I am trying to convert a line shapefile into a polygon shapefile using Polygonizer plugin, and when my new polygons are created all the cells in my id field are "Null", although I have clicked "copy ...
3
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63 views

Detect connections along shapefile in QGIS?

I have a set of polylines and a set of points that lie along or very near to the polylines, and I need a way to measure which points are connected to each other along the polylines, and what the ...
3
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0answers
158 views

QGIS: GPS Tracking with improved Altitude

I am preparing for archeological fieldwork in Sudan. I recently came up with RTK equipment and software using RTKlib to export the real time corrected data (cm level) to QGIS via a simulated NMEA ...
3
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225 views

How do I access layer attributes from within QGIS' manageR plugin?

This is probably a fairly basic question, but searches for manageR come up with a lot of noise, and there's no manageR tag. What I'd like to do is load the attributes from a particular field of a ...
3
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204 views

How to symbolize vector features using RGB values stored in three fields?

I need to symbolize a vector layer in Arcmap based on RGB (or HSB - can do either) values found in fields in the attribute table. I'm working with up to 10 different datasets, each with over 100 ...
3
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0answers
127 views

Does QGIS have WMS-T (WMS with time) support?

Does anyone know if there's support for WMS-T in QGIS? Through the app I can add WMS layers, but I can't work with WMS-T (there's no place to set the time parameter). I been going through the the ...
3
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215 views

How to access tiles in Tilecache using QGIS?

I've Mapserver set up with a mapfile that points to a tileindex. In QGIS I can call the mapfile and view the rasters dynamically. I've got access to tilecache and I've seeded the same mapfile/rasters ...
3
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158 views

How to create unfilled circles (style) for point layers?

I have a point layer and want to visualize it with unfilled circles. It is only possible to change the colors and size of the symbology layer (single mark). But I would like to change the filled ...
3
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300 views

How to set up a QGIS project in MVS 2008?

I have built QGIS using Visual Studio 2008. I would now like to start using the QGIS API for Windows Development. Of course I have Qt installed on Studio I hope correctly. I am new to Visual Studio ...
3
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340 views

How to offset points along line in QGIS?

I used the "Profile from Line" plugin to create evenly spaced points along a line in QGIS, but I'd like to offset them to either side of the line. I spose I could draw two lines parallel to the ...
3
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268 views

MapServer WMS feed and QGIS

I've managed to create a WMS feed from Mapserver showing a tileindex to some rasters and a shapefile and it appears in my browser OK. If I go to QGIS (1.8.0 Windows StandAlone) and I connect to my WMS ...
3
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0answers
224 views

Why do our .shx files disappear?

We are using QGIS in our workgroup, and have recently updated to 1.8.0 Lisboa. To share our file structure we are using egnyte similar to dropbox. We all use Mac OS, and have used QGIS for years, ...
3
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0answers
1k views

How to open a file geodatabase with tables and relationships in QGIS?

How can I open or connect to an ESRI file geodatabase in QGIS? I don't want to only see the features (shapes), I want to make sure that tables and relationships are opened correctly, too. Thanks in ...
3
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260 views

Freehand plugin query

I've installed the QGIS 'Freehand' plugin and I have a query regarding it. When drawing a polygon qgis automatically closes the polygon when the pen leaves the graphic tablet. Is there any way to ...
3
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353 views

How to reverse-georeference with QGIS?

I have a map with a "strange" projection (it's basically hand-painted, not an exact one). I can easily georeference it in QGIS using the Georeferencer plugin and the Thin Plate Spline transformation ...
3
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381 views

How to export multiple Shapefiles to one KML file in QGIS?

As the title says, is it possible to export multiple Shapefiles to one single KML in Quantum GIS (Similar to "Map to KML" in ArcMAP)?
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769 views

How to create point labels from midpoints of road polylines in QGIS?

Heres what i want to achieve: i have a roading polyline layer (singlepart ie has several features per road, grouped by an id field), and i want to (after merging the parts) find the mid point of the ...
2
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0answers
22 views

Programmatically change layer position in the table of contents (QGIS)

I am trying move/position a layer to the bottom of the TOC by using addTopLevelItem on all other layers. I unsure how to reference the layers as QTreeWidgetItem's. def bg_bottom_level_item(self): ...
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votes
0answers
84 views

How to eliminate gaps and overlaps in a layer of SpatiaLite table?

I'm try to snap all polygons in a table to remove gaps and overlaps. I can remove gaps but get new overlaps. I have no idea what doing wrong... sorry, I'm new in SpatiaLite. I tried the following: ...
2
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0answers
32 views

Using Field Calculator to Convert Data Type In Field

I am trying to convert a field that is listed as "String" because it was imported into QGIS as a CSV (rural poverty population percentages by county in NC). I need to convert the percentages field ...
2
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0answers
33 views

How to open QGIS attribute table in form view using Python?

I've got a plugin where I load some layers. On the last layer loaded I show the attribute table. I would like to select the view different from the table view (see image). How can I do this in Python? ...
2
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0answers
38 views

Zonal Statistics Freezing QGIS 2.2

Running on Windows; 8gb memory, 500gb HD, i5 cpu; Raster file: 250mb I am having a problem with zonal statistics advancing past 17%. I am trying to run statistics on a crop grown in certain counties. ...
2
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0answers
30 views

QGIS Labels: letter or word spacing ignored after export

My line label have letter spacing of 3px (Layer Properties -> Labels -> Text -> Spacing -> Letter). In print composer everything is drawn like I want it but after export to svg, pdf, or image the ...
2
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37 views

Does QGIS support .sld style files for raster layers?

I'm currently looking at the documentation for geoserver, and I'm trying to load a raster and .sld file in QGIS to see if I can edit .sld files for raster layers. The .sld and raster are located here: ...
2
votes
0answers
92 views

Per-pixel calculations on a raster stack using GDAL

In R, it's relatively trivial to perform per pixel calculations based on a raster stack (e.g., get std.dev for each pixel on a 12 layer GeoTIFF). Unfortunately, the speed is less than desirable when ...
2
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0answers
61 views

Snap points to line and calculate chainage using Open source GIS

I have a line layer (representing a pipeline) and a points layer (representing valves) and I would like to calculate the chainage of the valves along the pipeline. I assume that I would first need ...
2
votes
0answers
25 views

How to set posgis default sequential value in a QGIS “editable” view?

Introduction In a QGIS project I have a VIEW, that I want to became editable (I'm trying to replicate the versioning system used DB Manager with some tweeks). Therefore I created a few rules to ...
2
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0answers
57 views

Move Scale Rotate raster in Qgis

I have some archaeological scanned raster that they have a north arrow and a scale bar. There is no grid, no coordinate system.I would like to put those files in a general map. I don't care about the ...
2
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0answers
33 views

QGIS: rotatable markers with offset from point

Im wondering, if its possible (in QGIS), to set a rotatable marker with offset from point, like in my example below. Any suggestion?
2
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0answers
59 views

How to display images as cross sections in 3d

I want to display a base map and several vertical cross sections in 3D. The base map image is easy to rectify as a geotiff. How can I also display the cross sections? The cross sections are at ...
2
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0answers
27 views

How do I limit update/insert/delete capabilities for a WMS layer in a QGIS project?

In QGIS 2.0 I have a layer based on a query to a PostgreSQL/PostGIS database and would like to serve this as a WFS layer. Users of the layer should be able to select subsets of the data based on ...
2
votes
0answers
157 views

Writing Stand Alone PyQGIS Script - QGIS 2.0

I have spent quite a bit of time looking for a clear answer this topic and have still been unable to really accomplish my goal of accessing PyQGIS in a stand alone script. Parts of answers have been ...
2
votes
0answers
73 views

How to add an offset to a GeoJSON layer in Leaflet?

Using the example GeoJSON tutorial code at leafletjs.com. Change the myLines variable so that the two lines overlap, but run in opposite directions as follows: var myLines = [{ "type": ...
2
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0answers
40 views

What is an Orphan point?

MY apologizes about the next doubt, but I can't understand what is an orphan point. I am using QGIS with a module to apply the Linear Reference System (the module is called "LRS"). During the ...
2
votes
0answers
136 views

How to use the linear referencing plugin?

I need a guide how to use this plugin properly, I'm a newbie on PostGIS and I'm trying to use the linear referencing plugin of QGIS. I've created a database on postgreSQL with the postGIS extension ...
2
votes
0answers
39 views

How do I calculate the distance among all points in set in QGIS?

I am a very new user of any GIS. In QGIS I have input my UTM data as a CSV file. Under Vector, Analysis Tools, Distance Matrix I have been able to create a distance matrix but it just takes point 1 ...
2
votes
0answers
78 views

Is there recommended true type font for search and rescue?

Has anyone run across a true type font set to use for search and rescue cartography, and/or fire cartography? This is specifically for Terrain Navigator Pro which isn't really a GIS application but ...
2
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0answers
111 views

How to merge points (bus stops) in QGIS manually or programmatically?

What I have: I have a large data-set containing links (bus routes( (>2000) and their respective nodes(bus-stops) (>6000). The data set I received from the local bus operator is very messy. It ...
2
votes
0answers
60 views

Longest slope oriented to north?

I need a help with my homework. I have created digital elevation model from the shapefile. In QGis(Grass plugin) This is how far i can go. I have to find the longest slope oriented to North. I know ...
2
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0answers
59 views

How to use buffer() in QGIS Value Relation field

When adding a point, I'd like to auto-populate one of its fields (the street address) setting it to a field in the nearest point in another layer (a layer containing all existing addresses). It ...
2
votes
0answers
84 views

QGIS, “Handle bad layers” and empty layers

I'm a novice in GIS, so forgive me all possible mistakes I might have here... I'm using QGIS 2.0.1. (Dufour) with Mac OS X (10.6.8). I have couple of dozens(?) of vector layers added on a project. ...
2
votes
0answers
62 views

quantile calculation in qgis

I have a simple question about the graduated classification in qgis (version 2.0.1). I can choose between several statistical methods to classify my data (standard deviation, quantile, natural ...