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

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QGIS - Is it possible to Animate Polygons based on column values? [duplicate]

If you have an number of polygons with numeric data across 4 attributes/columns, you can display the data for one column but can you automatically cycle through the values for other selected columns? ...
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72 views

How to fix “No QGIS data provider plugins found” erros in QGIS for Android?

I've bought a Samsung galaxy note 10.1 2014 edition, running with android 4.3. I've downloaded several versions of qgis for android (7 and 9). When I start QGIS, the message "No QGIS data provider ...
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50 views

How to create a new table with point geometry column using QGIS DB Manager?

I have been trying to use QGIS DB Manager to create an empty table (QGIS 2.0 on Win7). My hope is that I can make an empty point file and use it to add data to, via heads-up digitizing (like you ...
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0answers
62 views

Maximum scale dependent visibility changes from 1:0 to -2147483648:1

QGIS 2.0.1 Dufour. When i open the layer properties and the scale dependent visibility is unchecked and when i check it, the maximum (inclusive) shows 1:0. I click Apply, OK, reopen layer properties ...
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25 views

How to draw some ellipses that can cover some categorized points automatically in QGIS?

Instead of using Rectangles Ovals Digitizing plugin to draw some ellipses manually, is there another way to draw them automatically that can cover some categorized points in QGIS?
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1answer
55 views

Can QGIS report/calculate areas/perimeters of individual polygon components within multipart shapefile?

Can QGIS report/calculate the areas/perimeters of individual polygon components within a multipart shapefile without using the "explode" vector tool to generate a new file? using QGIS 2.2.0 on ...
1
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2answers
131 views

Breaklines in QGIS interpolation plugin

How can I prepare data to generate a DTM using points and breaklines, but where every breakline has nodes at different heights. For example, a river valley, which regularly falls, or a dorsal line, ...
1
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2answers
239 views

How do I open images georeferenced in ArcMap in QGIS? (.aux.xml)

We have several ArcMap georeferenced images (raster datasets) that we are attempting to open in QGIS without any luck. These are not inside of a geodatabase and are not Arcinfo Binary Grid format or ...
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24 views

QGIS - unable to change projections [duplicate]

I am relatively new to QGIS (version! 2.0.1) and having trouble changing projections. No matter what I choose the view is the same. For example, in the attached screen shot I have chosen Alaska Albers ...
3
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1answer
80 views

Re-registering a GEOTIFF in qgis

I'm working on some images taken from a UAV over the course of a year. They are OSGB 1936 projection as is the whole project. Annoyingly they don't quite line up so I am trying to a few of the images ...
3
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1answer
100 views

Where is qgis getting the NO DATA value from?

I have a project that contains an 8-bit paletted layer (call it the mask layer) and a float 32 single band layer (call this the clip layer). I create a new raster by using the raster calculator, ...
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44 views

Why does heatmap size vary with number of points

I am making three heatmaps based on points over the same area and don’t understand why the number of rows and columns would vary depending on the number of features. The first feature set has 398 ...
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0answers
34 views

Error running SEXTANTE in QGIS on Scientific Linux

I've installed SEXTANTE into qgis on my Scientific Linux machine and I am getting the following when attempting to run Warp; INFO|Mon Feb 24 2014 15:56:20|GDAL execution console output|/bin/sh: ...
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0answers
44 views

How to get the signal when the color changes in pyQGIS?

I would like to have the signal when the color of a vector layer is changed by the user. In the doc, there is a signal that seems to fit ...
1
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0answers
35 views

“System not initialized. Programmer forgot to call G_gisinit().” message when loading table into GRASS via QGis

I am trying to load a CSV table into Grass with v.in.asciifrom the interface of Qgis 2.0.1 on Windows XP. As the progress bar indicated 74% of the data already loaded, I got the message "System not ...
3
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1answer
192 views

Qgis 2.2 how to fix bad epsg.wkt load

I installed Qgis 2.2 this morning from the ubuntugis repository for ubuntu precise. Qgis works great, except that all the common projections have been deleted. So, I am a Little bit having a heart ...
4
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0answers
283 views

How to configure QGIS and SAGA on Ubuntu (12.04 and others)?

During the past weeks, I have tried QGIS to recognize SAGA via the processing toolbox, both being installed from the ubuntugis-unstable repository. I have tried this on several virtual ubuntu ...
2
votes
1answer
30 views

Wrong sorting of elevation classes QGIS

I'm a totally beginner with QGIS and maybe I have a very easy problem, but I can't help myself. I got an elevation shapefile with classes of elevations like that: 1-100m, 101-200m, ... When I try to ...
3
votes
2answers
393 views

QGIS GISBASE specify location

I am just a beginner at this QGIS and GRASS and I am using this QGIS 2.0.1 Dufour which throws a error at the startup that "QGIS couldn't find your GRASS installation. Would you like to ...
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0answers
56 views

Define Projection for an autocad transferred data

If I had a cadastral map on an Autocad file and i convert it to a dxf extension in order to open it in QGIS. I Added The Parcels borders and text in QGIS. Can you please list the steps which I should ...
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0answers
34 views

display route from database(postgresql) on

For first part: Link i have postgresql9.1,postgis2,pgrouting2 and qgis2.2 this is the second part of what i need to do: Search in a database (postgresql with pgrouting) for a line from public ...
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0answers
55 views

How to Simulate Venn Diagram of Buffers using QGIS?

For the sake of simplicity, suppose I have only 2 points on one layer. Point A have population of 100, and point B have population of 150. I do find buffer of these 2 points and it is intersect. I ...
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0answers
105 views

how to add polylines(routes from public transport) on postgresql(pgrouting) with GUI

After searching a several long time... i decide to ask here for help, im currently using ubuntu 12.04(because of compatibility) with postgresql 9.1, postgis2, pgrouting2 and qgis2.2 i need ...
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0answers
88 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 ...
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45 views

Directly Proportional Hexbin Cartograms in QGIS

I've been using Scapetoad to create population cartograms, which I then convert into hexbins back in QGIS. However, the Scapetoad software seems to create cartograms that are affected, but not ...
2
votes
1answer
113 views

How to write a new layer to PostgreSQL from QGIS plugin

The PyQGIS cookbook states that QgsVectorFileWriter can write vector layers to any format supported by OGR: https://www.qgis.org/en/docs/pyqgis_developer_cookbook/vector.html#writing-vector-layers ...
1
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1answer
87 views

Can I automatically save datetime for every entry in my spatialite tabel? [duplicate]

I'm using QGis and SaptiaLite. Is it pssible to store date and time in a field "datetime" for every entry automatically - maybe with some python code? Already existing datetime should not be updated. ...
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2answers
184 views

How can I centralize QGIS connections for multiple QGIS installations

I have multiple computers with QGIS installed on them. I regularly use the same WMS / WFS services. Now I have to connect to these services for each QGIS installation separately. It would be great ...
0
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1answer
88 views

v.edit break: how to loop through XY coordinates on using GRASS on Windows 7

Trying to follow the suggestions on this thread: splitting a lines layer using points However, how to do so in a windows environment using the GRASS command console is beyond me, so I'm attempting ...
2
votes
4answers
317 views

How to turn all lines into one direction?

How can I turn all features of my polyline (postgis and/or shapefile) into one direction - it doesn't matter what direction. I know how to switch the direction of lines but I have no idea how to ...
2
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2answers
74 views

Open Arabic Shapefile in Qgis

I have a shape-file all it's fields are in Arabic. When I opens it in qgis 2.0 all the data is replaced by "?". I changed the encoding to Arabic or UTF-8 but with the same result. How can I Open an ...
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0answers
40 views

Adding a GRASS module manually in QGIS (Mac OS X)?

I am trying to add a precompiled non-standard GRASS module to QGIS 2.0.1 (MAC OS 10.9.1, using the binaries by Kyngchaos). Adapting the instructions here ...
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0answers
35 views

How to export QGIS elevation data to Mysql WAMP

is there a way to export elevation data from QGIS to wamp server(mysql)? please help me. I need to store all the data to mysql wamp.. thanks!
1
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1answer
63 views

Why do features in QGIS drawn on same datum as Google imagery from OpenLayers move? [duplicate]

I have just started using QGIS. I've loaded the "openlayers" plugin and added a google hybrid layer, which is based off the WGS84 datum to my understanding. Now I create a shapefile and add a new line ...
2
votes
1answer
95 views

Is there a limit to the amount of data in a spatial join in QGIS?

I am using Quantum GIS and trying to spatially join a point grid with polygons that are overlapping. If I get the sum of intersecting features, then I can get a good raster value. Well, every time I ...
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0answers
37 views

Zonal statistics won't work after re-projecting vector layer

I have qgis 2.0. I want to analyze raster information within a buffer of 30 miles around a vector layer of cities across the world. However, both the raster and the vector are in WGS84. I have no ...
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2answers
136 views

QGIS Installation - Oracle Link

Trying to connect an oracle 10g database to QGIS. I'm getting the error below: ORA - 12154: TNS:Could not resolve the connect identifier specified Anybody ever seen this error, or could provide some ...
1
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1answer
114 views

Calculate distances between polygon centres in QGIS

Is there a practical way to calculate distances between polygon centroids in QGIS? I have a UK city region map divided into administrative units (1 ward = 1 polygon). I want to represent their ...
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0answers
42 views

How to add field to postgres layer with PyQgis?

I'm fetching a posgtres layer with PyQgis and then I'm trying to add field with this: lyr.startEditing() lyr.addAttribute(QgsField("class", QVariant.Int)) But It is not adding the field and also ...
2
votes
2answers
125 views

How to produce a CSV file from .tif file with elevation data? [duplicate]

just want to ask, I have a .tif file that contains all the elevation of a country. How can I convert that to a CSV file that contains x,y,z values where x and y are the latitude longitude respectively ...
1
vote
2answers
46 views

QGIS 2.0 How can i get a precisely Rendering time?

I work with QGIS 2.0.1. I have a large number of raster data files and i selected different methods to represent them. Method: Import all raster data as individual files Method: Generate a single ...
3
votes
1answer
164 views

Plugin Tutorial issue: trying to work around changes in QGIS API

I'm currently following the tutorial to create my first python plugin for QGIS: http://www.qgisworkshop.org/html/workshop/plugins_tutorial.html and have similar issues to this thread: QGIS 2.0 Plugin: ...
4
votes
4answers
230 views

How to georeference Tiffs after manipulation in Photoshop?

I am exporting very high-res (7000x7000px) hillshades from ArcMap as tiff files. I am then doing some work in photoshop to the images. How can I easily georeference these tiffs after working on them ...
1
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1answer
63 views

Why am I losing part of my raster when I reproject?

QGIS 2.0 Working with tiff raster file. Reprojections are in WGS84 Mercator. Here is my problem: I am trying to use buffers or urban areas to analyze light intensity on a raster layer. I want 30 ...
2
votes
3answers
476 views

How to reproject WGS84 to a metric coordinate system with own reference point in QGIS?

I have GIS data in EPSG:4326 consisting of 2D points, linestrings and polygons that are all close (i.e. less then a couple of hundred of meters) to a certain WGS84 coordinate point. I would like to ...
1
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1answer
81 views

How do I get the vector output segmentation algorithms to work properly in QGIS 2.0?

I'm trying to run the Watershed Segmentation algorithm, specifically, but I have been receiving the same error message using any of the available segmentation algorithms. I'm new to QGIS and have been ...
2
votes
1answer
67 views

QGis draw over simple jpeg image

I'm pretty new to GIS, and since 2 months ago QGIS is a great tool to achieve very simple tasks, such open some shapefiles I find in the web and load that data on my website geoJSON formatted. Now ...
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0answers
56 views

How to apply categorized symbols to polygon layer with PyQgis?

I'm fetching a polygon layer from postgres like this: uri = QgsDataSourceURI() uri.setConnection("localhost", "5432", "mydb", "postgres", "xxx") uri.setDataSource("public", "my_table", "geom") lyr = ...
0
votes
1answer
36 views

Why is the map content not displayed when I reopen Print Composer?

I just updated from QGIS 1.7 to 2.0 on Mac. When I now open a project and create a map in the print composer the content of the map is lost when I open the project again later. The settings of the ...
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2answers
142 views

Unable to implement pgrouting(plugin) pgr_astar routing algorithm (shortest path) [duplicate]

I have been working on a project for indoor navigation. I made the floorplan of the building and road-map for routing purposes as shp files (using JOSM, making GeoJSON and then converting to shp file ...