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

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271 views

Setting up PyCharm CE 4 to work with PyQGIS library in Mac OS

I am trying to set up pycharm to work with pyQgis library but with not success till now. I am using PyCharm CE v4 and QGIS version 2.8 I have tried to implemnte the instructions of several posts like ...
3
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1answer
496 views

How to create and remove multiple QgsRubberBands in PyQGIS?

Currently the following code-snip works great to highlight a shape based on the 'feature' and 'layer' variables: self.rubberHighlight = QgsRubberBand(self.iface.mapCanvas(),QGis.Polygon) self....
2
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1answer
244 views

What's the QGIS Legend Format Syntax to have thousands separated by commas?

I have numbers in the millions and would like to know what string to enter in the Legend Format box to have thousands separated by commas ex: 2,000,000
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1answer
142 views

How to use QGIS field calculator between different points of same layer?

I'm in a course learning about GIS systems, and we have recently recorded a gps track. I've exported this track as .gpx and imported the points into QGIS. Each point has a timestamp. One of the ...
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1answer
114 views

How to detect that QGIS is shutting down in a plugin?

I built a plugin in QGIS and needs to stop it when user wants to exit to remove signals and close properly. How can I get an event when QGIS is exiting ?
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0answers
172 views

Is there way to define processing extent in QGIS?

Is it possible to define the extent of a processing tool, like it is in the "Environments" in ArcGIS? For example "Same as Display, or "Same as Layer..".
3
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3answers
1k views

How to create a compressed GeoTIFF with the QGIS Clipper tool?

I have a geo-tiff created by Pix4D which is about 375 Mb in file size. I have clipped it to a smaller area using Qgis 2.8(using Raster ‣ Extraction ‣ Clipper), and the output file is about 900 MB in ...
7
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1answer
341 views

Is it possible to use memory layers in QGIS processing algorithms?

I am building a QGIS plugin that connects to a MySQL database in the local network, and then adds a subset of one of the tables to an in-memory layer; the subset is based on data currency (only taking ...
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0answers
132 views

Deriving length values from GPX files in QGIS

I’m missing something real obvious and I apologize for revisiting a topic addressed in several Q&A’s here. I’m an experienced GIS user (not programmer) who’s new to QGIS (can’t afford Arc in ...
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0answers
15 views

Using QGIS to create a single # band raster Image [duplicate]

I recently downloaded some Landsat Images. They are in GeoTIFF format. The images are in the different bands. How can I combine them for example if band 1 is Red , band 2 is green and band 3 is blue, ...
2
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1answer
1k views

Can we avoid using SIP library when writing standalone QGIS python script

I wanted to write a small custom python script using QGIS functionality. So I started with the QGIS documentation on the custom application section. After having some troubles with the import qgis....
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1answer
58 views

QGIS 2.8.1 Consult a space object and to lead me to a specific folder

Folders display in QGIS clicking on an item. I desire to help me because it is very important. I need you to click on a space object redirect me to a desired folder. Mostrar Carpetas en QGIS al ...
3
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2answers
660 views

Creating polygons from line segments using PostgreSQL and PostGIS

Is there a PostGIS function that creates polygons from multiple line segments? I want to convert the pictured thirteen lines to four polygons. All lines belong to the table "boundary" (gid, geom). I'...
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0answers
64 views

QGis Application Debugging - missing source problem at setScene method in QgsMapCanvas class [closed]

I develop a app in C++ with Qgis components with VS2010 Prof on Windows 7. Compiling a release succeeded and the app´s behaviour is as expected. Nevertheless I would like to take advantage of the ...
2
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1answer
143 views

Multiple ComposerMap items not rendering properly Pyqgis

I am currently trying to put together compositions using inputs from two different map canvases. One is from a canvas built and controlled via a plugin, the other is the the main QGIS canvas (accessed ...
1
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1answer
467 views

QGIS Numerical Vertex Edit - anyone else finding it doesn't work?

The QGIS Numerical Vertex Edit plug-in used to work fine, but stopped working for me around about QGIS 2.6. I now use QGIS 2.8.1 Windows 64 bit. The plug-in no longer seems able to see points or ...
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0answers
91 views

Progress Bar gets stuck converting Lines to Polygons using QGIS?

I'm trying to convert lines to polygon using QGIS 2.8.1. I use Vector > Geometry Tools > Polygons to Lines. I always get the progress bar stuck on 90%, it can't get to 100%. Could someone ...
0
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2answers
650 views

How to create/obtain district data for Singapore? [closed]

I am newbie in GIS and have started using QGIS. I am hoping to map all districts of Singapore and create a Shapefile and get GeoJSON details for all districts. I am not able to find that currently. ...
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0answers
75 views

QGIS and Intel Tablet Processor Compatibility

Will any Windows based tablet with an intel processor be able to run QGIS, provided it meets the requirements, or is it only the Surface Pro that is capable? Looking for a cheaper solution to the pro.
2
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3answers
638 views

PyQGIS - load PostGIS layer as editable

I can load a PostGIS layer on QGIS' map canvas but "Toggle Editing" button comes "inactive". How can I load vector layer as editable? The code given below loads PostGIS layer on map canvas & "...
1
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1answer
104 views

Giving line features of same layer different colours

I have one layer and there I have different lines. Imagine these lines are pathes of persons. So image a person x and y. And I now want to differ them by just watching on the different colours of the ...
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0answers
83 views

GRASS GIS r.slope.aspect write errors

I am running into an error running r.slope.aspect I have never seen before. When I run it, I get the following output: r.in.gdal complete. Raster map <dem> created. WARNING: map [slope] - ...
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1answer
85 views

I can't add an img file to QGIS 2.8.1 on Ubuntu 15.04

When I try to add an img file to QGIS 2.8.1 with Ubuntu 15.04 I get this error message: Raster layer: /media/thomsec/D/Nu_Data/world/ocean_floor/age.3.2.img/age.3.2.img is not a supported raster data ...
2
votes
1answer
395 views

Create a regular grid of sample points with angle and give them a value

I'm mapping able points to archaeological research. Using QGIS, I need to create a regular grid of sample points, give them a value, specifying spacing and rotation. Better if it results inside a ...
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0answers
39 views

Why are text values ending up in wingdings or something similarly useless?

I have dissolved a layer in QGIS 2.8. The resulting layer has all the column labels and text fields changed to wingdings or something similarly useless. When I look at the layer in ArcGIS, there is no ...
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1answer
25 views

Does Scimap work with QGIS?

Does anybody know if Scimap ( http://www.scimap.org.uk ) works with QGIS? I know it is supposed to operate with ArcGIS and SAGA but as I am very much a beginner with QGIS I would like to know if its ...
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0answers
45 views

How to open none .qgs files in QGIS Wien? [duplicate]

I have tried tried to open my older qgis files made on a mac on my new PC. Wien(2.8) only seems to allow .qgs files so all my folders appears empty when I access them from QGIS on the PC.
3
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1answer
578 views

Using Cassini-Soldner projection in QGIS?

I have a shapefile in a Cassini Soldner reference system centered in Monte Mario (Italian cadastre map). I want to insert these data inside QGIS in order to compare data with aerial images. When ...
1
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1answer
502 views

How to view a postgis raster query in QGIS

I have successfully loaded a large number of .asc images (>2800 200x200 tiles) into a Postgres table with PostGIS 2.1 support. The new table appears in QGIS's DB Manager and I can add the whole image ...
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0answers
28 views

Nothing in the feature box QGIS?

When I add a feature, the feature attribute box comes up but it has nothing in it...completely blank, no fields. It used to come up but stopped. I have re-installed it but the same thing occurs.
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1answer
61 views

Is it possible to create print templates in 2.6 and 2.8?

Is this possible? I can only find the option to 'Add items from template'. When using this option, the page setup defaults to A4 landscape and you must manually change these settings using the ...
2
votes
3answers
109 views

How to create a point between two other points in QGIS?

We are capturing sample points from survey maps. In between two points we have to introduce another point (as in fig), like - if the sample points are 42 and 42.5 we have to introduce another point ...
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0answers
54 views

How to extract the raster files from .prj?

I am interested in using Raster Calculator tool for which i need the desired raster files. But i came across a problem i.e. when i converted my vector files to raster and saved them they were saved ...
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0answers
26 views

Branching factor in River system?

I would like to find the branching factor for a river system. I have tried dissolving it then trying to find the branching factor but I'm not to sure how. So I have it from west to east like it ...
2
votes
2answers
504 views

How to get path for layers listed in a combobox?

I want to get the path of a layer in my plugin, in the console it works fine but in my plugin it gives me the error AttributeError: 'NoneType' object has no attribute 'dataProvider' def run(self): "...
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42 views

Using QGIS in medical Science? [closed]

I was wondering if anybody would be interested in collaborating? My Idea is using QGIS to analyze and quantify Immunofluorescence raster images of cells from human serum.
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0answers
60 views

How to compute and label distance between points on a line?

I have a line and i want to find and label the distance between the nodes (like the cad aligned distance). v.distance outputs an empty vector file. Is there another way?
11
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4answers
1k views

How to model a graveyard - one point per deceased or one per grave? [closed]

This is a continuation of my previous question about our project on how to economically get away with the implementaion of a graveyard in a GIS system… On the graveyard we can find Regular ...
3
votes
2answers
256 views

How to remove a certain number of digits from the front or end of an attribute field?

Can I use the filed calculator in QGIS somehow to remove the first 4 numbers in all attribute fields in a column? Example 16011234 -> 1234 EDIT: Silly, I can just subtract with 16000000 in this ...
0
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0answers
87 views

Georeference Error Messsage QGIS

I'm trying to georeference a 1922 map of Africa by Bartholomew. (found here http://www.davidrumsey.com/maps5268.html). I have it in QGIS and currently the Raster has the default CRS (WGS 84). I have ...
3
votes
2answers
811 views

How to display a picture in QGIS custom form?

I'd like to integrate an UI file as a form in QGIS 2.8. The UI file is created in QT Designer. One of the attributes in the attribute table is a filepath to an image. I'd like to display the picture ...
0
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1answer
185 views

QGIS C++ Hello World example crashing

I have written a very simple C++/Qt application using QGIS comprised of a single "main.cpp" file as below: #include <qgsapplication.h> int main(int argc, char ** argv) { QgsApplication app(...
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1answer
361 views

QGIS Wien 2.8.1 RuntimeError concerning the sip module on Win 7

I am running windows 7 64bit and python 2.7.9 I just installed QGIS Wien 2.8.1 and it crashes on start up with the following code: Couldn't load PyQGIS. Python support will be disabled. Traceback (...
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0answers
183 views

Limit Extent of OpenLayers Map in QGis

I am trying to work with a OpenStreet map of Ontario, using the OpenLayers plugin. The problem is that the entire global view renders, slowing down my work. A couple of solutions come to mind: ...
0
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1answer
69 views

Merging SHP lines with attribute data combined?

I have one shapefile which contains hiking routes and another shapefile which has ski routes. Sometimes they follow the exact same path. In QGIS if the lines mentioned above are in the same SHP I ...
3
votes
1answer
540 views

Processing plugin Python error on startup of QGIS 2.8.1

I've been running QGIS with no issues for several versions now, but after I upgraded to 2.8.1 Wien I had trouble running two plugins: qgis2leaf (which I believe depends on Processing) and Processing. ...
2
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0answers
118 views

Why is SAGA kriging slower in QGIS than in SAGA itself?

I'm using QGIS for a while. In my opinion the SAGA kriging tool (processing toolbox) is very slow. Is that an QGIS issue? I tried to interpolate a point layer with 300.000 points (I know it is big) ...
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0answers
28 views

install python packages for qgis? [duplicate]

I need the twisted framework (Python) for a qgis plugin on Windows 7. I installed it with the pip installer. When I want to start the plugin it doesn't find twisted. When I start a python interpreter ...
0
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1answer
158 views

Merge touching polygons with keeping their attributes

I've got a layer of polygons Although they all in the same layer, each polygon own some unique data like the date of this polygon and an amount it possess (a number). I want to join/merge all the ...
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0answers
77 views

Incomplete results from an intersection

I am trying to map the density of buildings in flood-prone areas. In order to do that, I created a grid of equal-sized squares. I want to intersect the layer of buildings with the grid so I can ...