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

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37 views

Is setting raster CRS in QGIS georeferencer useless? Still have to choose the same for target SRS?

I'm trying to move out of ArcGIS into QGIS permanently for basic operations, so be patient please. Here is the problem. I'm trying to georeference a topo map in EPSG:22523 (Corrego Alegre UTM). I did ...
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9 views

Problem on rendering categorizedSymbolRendererV2

Finally my code works but the renderering display just one color instead of 4 I don't know why, I follow the sample code of the snorf.net website and the sample code in the qgis python programming ...
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0answers
7 views

How can I inject categorizedSymbolRenderer into My QgsFeatureRenderer?

I try to get the categorizedSymbolRenderer value in order to render them In all sample of code I found ( in python but not in c++ ) it said : renderer = QgsCategorizedSymbolRendererV2(expression , ...
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1answer
23 views

How can I change the folder location for QGIS temporary files?

Even though I specify specific files for output, there are still a lot of temporary data being written to C:\Users\me\AppData\etc My C drive is a very limited capacity SSD and it's driving me nuts ...
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7 views

Why I have a SegFault on a newSymbol->setColor?

I am working in C++ and QT, I have to write an application based on the qgis c++ api 2.8.2. So, I try to do the same thing that the sample code in python on the webSite ...
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1answer
21 views

QGIS imported geotiff rendered as perspective view, how to change to top

I've created a GeoTiff that should have GPS coordinates in it using AgiSoft. When I load it into QGIS, it renders the image in a perspective and I want to always see the image from the "top" down. ...
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2answers
39 views

QGIS 2.10.1 (64bit) rotation field setting missing

I cannot find the the rotation field setting under the properties-layer settings-advanced (for styles) menu in the new release of QGIS (2.10.1 64bit). The only setting what is available there is the ...
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21 views

Making raster from vector

Have you ever met with nan value in raster? Im making raster in qgis from vector (one point) and all I have got is nan value and black raster.
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24 views

Can I use .aux, .sid, .sid.xml, .sid.aux.xml, or .sdw files as raster in QGIS?

I am working with data from my boss who uses ArcGIS. I am aware that .aux files accompany raster files, but to my knowledge you can still use .aux files to create rasters in ArcGIS. I'm working with ...
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1answer
25 views

How to create a new empty memory layer with fields scheme from other layer in QGIS?

Being a complete noob with python so far, I got inspired by this answer: http://gis.stackexchange.com/a/155988/8202 to dive into it a bit. When creating features in a new target layer from an ...
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0answers
20 views

QGIS RGB image to HSL (Hue Saturation Luminance)

is it possible using QGIS (2.10) on windows to convert an RGB image file to HSL (Hue Saturation Luminance) format. I've seen various formulas for this written in Java however they only seem to be for ...
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17 views

How can I connect MYSQL database in python for QGIS desktop Application?

I am following below process. 1 - Setting You must install a MySQL driver before doing anything. Unlike PHP, only the SQLite driver is installed by default with Python. The most used package to do ...
2
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1answer
41 views

How to place labels at the boundary of the current map extent

I have a layer of reference grid lines on top of several map layers. The grid lines should be labeled with coordinate values: vertical grid lines with x-values and horizontal lines with y-values. The ...
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0answers
22 views

Fail in searches on the joined table data

When a table is joined to a standalone table, the searches on the joined table data return a fail. Is there another way to solve this inconvenient without save the layer with joined table under a new ...
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2answers
44 views

Opening HDF data in QGIS on Ubuntu?

I try to open modis aqua data (HDF5 format: A2015208112000.L2_LAC_OC.nc) on QGIS 2.8 ver. And an error appears: No extra dimensions found. Could someone help me to solve this problem?
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0answers
25 views

Join tables in QGis 2.01. Dufour

I performed a "join" going to the properties option in a shapefile (in this case is just a table), in order to join the attributes from another shapefile that has a field in common, specifically ...
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0answers
9 views

dynamic styles for rasters in qgis processing

I am writing a qgis processing script that loops a table column and does interpolation and would like to know if it is it possible to generate styles on the fly for raster layers and how to do it. I ...
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1answer
19 views

Information about the setDataDefinedProperty

In the QGis C++ API v1.6 there is a function called setlowerValue to set a value for a specific Symbol In my application i use QGis C++ API 2.8.2, i try to understand how the function ...
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0answers
24 views

Using Multiprocessing inside a plugin in Qgis

I spent quite a bit of time looking on how to use the multiprocessing package, but couldn't find anything on how to use it inside a plugin in QGIS. I am developing a plugin that does some ...
1
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1answer
14 views

Relation Reference to simulate filtered drop-down lists

I have a layer of Land Uses that has a 3-tiered classification system (basically so that it can be broken down for different uses by other people). I have managed to create Project Relations and use ...
2
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1answer
20 views

How to automatically load QGIS actions

There is something that I like alot in QGIS, and that is actions. From automatic wikipedia search, to opening an image, this use makes QGIS feel very dynamic. Unfortunately I have no idea how to ...
2
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1answer
30 views

Share a qGIS sales territory database across a cloud based office

The business I work for has a network of dealers across America. Dealers are assigned ZIP codes. When we have a potential dealer, we would like to create a new territory for them and integrate it into ...
2
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1answer
57 views

Is it possible to animate a cartogram with FOSS GIS?

I was wondering if anyone knows of any FOSS tools to animate cartograms? By this, I mean 'tweening' between the geographic shapefile and the cartogram version of a shapefile. This means gradually ...
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1answer
32 views

How to make a square poly shapefile [duplicate]

I need a square polygon to clip layers to, in QGIS, a perfect square perhaps. It needs to be a certain size. Anyone have any experience or any good ideas? Thanks
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38 views

Finding out points overlapping with another polygon shape file

I have two shape files.. 1) HQ500(polygon flood shapefile which represents the level of flood in gridcode) and 2) transformer_Station(point representing location of transformer stations). ...
3
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2answers
54 views

Projection issues whilst opening shapefile in ArcMap created in QGIS

I created a polygon shapefile in QGIS. Projection was saved as EPSG: 3857, WGS 84 / Pseudo Mercator. When I open this shapefile in ArcMap the projection sets itself as WGS_84_World_Mercator which I ...
2
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2answers
34 views

Mean coordinate issue with multipart polygons

I've been using Mean Coordinates in QGIS to find weighted mean centers based on different attributes for the counties in a singular state of the US. However I have come across a problem in which the ...
2
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1answer
20 views

How do I create a bivariate map legend (3x3 cells) in QGIS?

I would like to create a bivariate map, and need to create a 2 dimensional legend to accompany it. How do I create a bivariate map legend (3x3 cells) in QGIS?
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2answers
54 views

How to join the attributes table from one input layer to another layer with unique id using python

I have one input layer with the attibute values and i wanted to join the attribute table of the input layer to the another layer with unique values using python. ...
2
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1answer
34 views

ST_Union based on attribute

I have a road network of center lines of MultiLinestrings.They have nodes at every intersection. I try to understand how I can merge roads together that have the same category as attribute (There are ...
3
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1answer
58 views

Exploding features based on numerical field in QGIS?

I have a set of data as polygons, each with a Number field with value X. Is there then a way to copy this into X number of polys at the same location? (ideally points distributed across the poly but ...
1
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1answer
41 views

Remove lines from inside a polygon in QGIS

Through a "dissolve" process in QGIS, I achieved some polygons that have some fails, like this one in the screeshot: Is there any automatic process I can make in QGIS to remove those lines inside ...
2
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1answer
90 views

Is there a Highest Position tool in QGIS

I am familiar with the tool Highest Position (Spatial Analyst) in Arcgis, but I am trying to replicate this tools function is QGIS. Is anyone aware if this tool exist in QGIS (possibly under a ...
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0answers
18 views

Vector layers don't seem to be exhibited properly [duplicate]

I'm a veterinarian that uses qGIS for making basic outbreaks maps, and am trying to branch out and expand what I'm doing. When I first started using qGIS 3 years (I believe it was 1.7), ago, when I ...
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0answers
35 views

how to use spatial index in spatialite query

I posted this question originally nearest neighbor query in SpatiaLite. Thanks to the answer given I was able to get the query working on some test data. However I am having trouble applying a spatial ...
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28 views

QGIS version migration of Styled Layer Files

I have a stand alone application which reads SLD files, to draw something on a map canvas (development started under QGIS version 2.0.1). Unfortunally I have to deal with these old SLD files version ...
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2answers
62 views

One-to-many join in QGIS

I am looking for a possibility to make a one-to-many table-join in QGIS. I have a shapefile with postal codes and would like to join them with survey results (more than one). In other words, there ...
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0answers
23 views

Can I use GeoJSON GeometryCollection in QGIS?

I want to create a GeoJSON that contains multiple geometries to be used in QGis later on. Now I red through the specs here: http://geojson.org/geojson-spec.html#geometrycollection When I simply copy ...
5
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2answers
115 views

How to run qgis scripts in parallel across remote server(s)

I have a stand alone python script using qgis that I wrote with the help of the SE question here The script takes three arguments being; an input file path, an output file path, and another input ...
2
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0answers
31 views

Adding elevation data to existing vector layer using QGIS?

I'm new to qgis and I'm having trouble adding elevation data to my existing vector file. I currently have two files: a road network with the all attribute information and a vector file with point ...
1
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1answer
48 views

Installing two versions of QGIS in Ubuntu?

I would like to have two versions of QGIS (2.8.2 and 2.8.10) in Ubuntu 14.04. I have tried to do it by using the SIG sem grilhetas tutorial. However, it didn't install qgis 2.8.2 in my ubuntu ...
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33 views

ZeroDivisionError

I was conducting Mean Coodinates process functions with weighted fields when I began faces ZeroDivision errors in some processes. The Shapefile Data has been joined together with imported Spreadsheet ...
3
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0answers
47 views

Soft edges for interpolation output

I've built the following heatmap using QGis 2.8.2's Raster->Interpolation feature. It looks almost the way I want: The background layer is Google Maps tiles by using the OpenLayers plugin. ...
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0answers
28 views

raster layer color legend with range of values

Is there a way to make clearer legends in qgis? At the very least indicating the range of values and whether the color includes the upper/lower limit of the range. if I make a discrete color ramp for ...
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0answers
55 views

How to create contours from an IDW raster

I'm new to QGIS and am trying to create vector contours from this IDW raster. I followed Ujaval Gandhi's "Interpolating Point Data" tutorial step by step but am not getting the same results for step ...
1
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1answer
37 views

Is there a way to integrate my own custom tools into the Processing toolbox in QGIS?

Is there a way to integrate my own custom tools into the Processing toolbox in QGIS? I believe I have found where to strategically hack the stock processing scripts to ensure it picks up my custom ...
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3answers
37 views

How can I get the UK Land Cover 2007 25m raster data set from Digimap to work in QGIS?

I have downloaded the UK Land Cover 2007 25m raster data set from Digimap (which my university has a subscription to). I have uploaded the data into ArcMap where it works fine, with all 23 classes and ...
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1answer
34 views

How to calculate azimuth in QGIS field calculator?

Is there any way to calculate the azimuth of two points in the QGIS field calculator? The coordinates are stored in an attribute table. x1 | y1 | x2 | y2
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1answer
81 views

How to install QGIS 2.8/2.10 on Ubuntu 14.1? [duplicate]

I have installed QGIS 2.0.1 on Ubuntu 14.1, yet I am not able to update to 2.8 or 2.10 since the proposed repository paths installations do not work. Anybody who can guide me through with a click ...
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1answer
51 views

QStringList() error in plugin of QGIS 2.10

I have made a Dialog in PyQt for use it like a plugin under QGIS 2.10 The Dialog works fine like a standalone application, but if I try to call it like a QGIS plugin, I get this error: ...