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

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2answers
35 views

How do I get UTM projected areas from a shape file created in QGIS?

I create a polygon (or point or line) .shp file in QGIS and it is automatically saved as WGS (as I understand, correct me if I'm wrong). That is fine by me despite being a bit inconvenient. Then I ...
1
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0answers
19 views

How do I step into the C++ functions from an external Python app I'm debugging?

I just wanted to see how to step into the C++ class QgsVectorLayer()'s methods from the python call to QgsVectorLayer(self.uri.uri(),'foo','postgres'). I'm trying to debug and it trying to step into ...
3
votes
1answer
45 views

How do I make curved labels for polygons in QGIS 2.6.1?

I have been able to find answers on how to do this in older versions of QGIS, but can't seem to come across anything that deals with the latest installment. I need a way to make labels curve to ...
2
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0answers
58 views

SAGA is not working within sextante (QGIS processing installed in Ubuntu)

Recently i decided to start working in Ubuntu (version 14.04). My first step was to add the ubuntugis-unestable repository, and then proceed to install SAGA, GRASS, OTB, QGIS and the bindings between ...
1
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0answers
47 views

How to extract percentage of land cover from a raster according to multiple shapefiles?

I have a raster map that represents land cover of a region, and different shapefiles (total 120) in the same region. I want to know the percentage of every land cover for each shapefile. For example, ...
0
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2answers
129 views

Import Aerial Images from Google into QGIS?

QGIS 2.6.1, Windows 7 I am looking to import an image from Google Earth into an existing QGIS project. Is it possible to download geo-referenced images from google maps (or google earth) and import ...
3
votes
1answer
83 views

How to compute Walking and Cycling Isochrone maps using QGIS & pgRouting?

Just installed QGIS as I believe I should be able to produce walking and cycling isochrones from a specified point. I have done this pretty easily before using ArcMap, however, I am really struggling ...
2
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1answer
77 views

Revert qgis 2.6 installation to qgis 2.4 through OSGeo4W Advanced installer

It is possible to return to qgis 2.4 OSGeo4W installation when I have qgis 2.6? I want with advanced installer. Thanks,
2
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1answer
27 views

remove unwanted areas which are not inside the boundary of second raster

1 raster layer - global map ; 2 raster layer - berlin I cropped out 1 layer using extent of 2 layer and then overlapped these two layers however I see that 1 layer still has areas apart from ...
1
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2answers
69 views

Call output files in temporary directory through Processing Toolbox (python)

I need to create temporary files as intermediate output to be used with processing algorithms. So, I implemented this: Processing.runalgorithm("grass:v.to.rast.attribute", ........, None) This line ...
1
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2answers
47 views

Issue in the popdown box (QComboBox) in QGIS 2.6 Python plugin

I had developed a plugin that counts the number of features for a layer in Qgis2.6. When i load a layer say 'Airport' for first time and click the pop-down box in the plugin,it lists the airport ...
2
votes
1answer
52 views

Symbolising null features in graduated symbology

I have a polygon feature dataset, and an attribute from a different table that I join (one-to-one) within QGIS in order to symbolise the attributes as a choropleth map. However, not all polygon fields ...
2
votes
1answer
39 views

Does anyone have any tips on figuring out why a Vector Layer didn't load in Pyqgis?

This is a general question. I'm stepping through the pyqgis code and the layer isValid() is always False. I don't see any error messages showing any reason why it wouldn't load. Other similars have ...
2
votes
1answer
49 views

How to scale SVG symbol based on zoom level in QGIS?

I am wondering if there is a way to scale SVG files I have stored as blob in a Spatialite database according to the current zoom level in QGIS. My hope is to have the SVG icon resize itself when the ...
1
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0answers
20 views

Edit WFS-T layers ArcGIS Server in QGIS

I'm trying to edit layers from a service in ArcGIS Server through WFS-T in QGIS. But the AGS only allows writing in version 1.1 of WFS, while QGIS only connects to the WFS Server in version 1.0, ...
0
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1answer
60 views

QGIS 2.6 Crashed for my own plugin

I had developed a plugin that counts the number of features for a layer in QGIS 2.6. I am using Windows 7 os. It works fine when i loaded a layer. But when I remove that added layer and then if I ...
3
votes
1answer
45 views

QGIS “ERROR 6: No translation for Lambert_Conformal_Conic to PROJ.4 format is known.”

I am trying to clip a county DEM file using the PLSS Section shape files as mask layers... that is, I want it clipped to sections so that I can load my DEM into QGIS one section at a time, without ...
2
votes
1answer
35 views

Command line error and missing dependency in QGIS

I have two problems with QGIS 2.6.1 1) When i am trying to open command line i get error: An error occurred during the execution of Python code: Traceback (most recent call last): File ...
1
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0answers
30 views

ArcMap KML Multigeometry to Shapefile

I have been troubleshooting this issue for quite some time now. I have a variety of tools available to me: ArcMap, QGIS, as well as OGR2OGR. Unfortunately, I have not had any success with any of these ...
3
votes
1answer
69 views

overlaying raster layer hides my vector layers in PyQGIS

I loaded vector layers and rendered them without a problem but when I tried to add a raster layer as well the map suddenly only shows the raster image and my vector layers are missing. Anything I can ...
0
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0answers
17 views

QGIS project lost when opening

I worked on cards a few weeks ago (in november), and when I open them again to day, I get this message "Le fichier projet est plus vieux: Ce projet a été sauvegardé sous une version plus ancienne de ...
1
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2answers
53 views

handling QgsVectorLayer (pyQGis begginer question)

I have a simple question. I am trying to start with pyQgis, but I have found it really hard to get a GOOD api Documentation, simple but yet useful. The one of you who did programming in the old ...
2
votes
2answers
86 views

How to mask labels in QGIS using an inverted polygon?

I created a file consists of a raster (snow load) and a vector with municipal boundaries. I added a vector with the contour lines of the snow load. Labels represent the snow load (kN / m2). With the ...
2
votes
1answer
44 views

Isolate features within buffer of another feature - QGIS

I have 2 shapes - one representing line features of pipes, another of roads. I would like to create a separate shapefile consisting only of the pipes that lie within 20m of the roads. Only the ...
2
votes
1answer
27 views

How to deal with QGIS Time Manager error: no attribute 'animationFrameCounter'?

I am using QGIS 2.6 and using the time manager I get the error shown in the attached pic. Anyone knows what the problem is and could someone offer a solution? Many thanks Nicole!
2
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0answers
17 views

QGIS - line between ordered layer of points - take attributes of both points

I have a series of locations in time in a point layer. I want to make a line layer of lines between consecutive points that takes the attributes (in my case, a timestamp) of the 1 points it connects. ...
0
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0answers
20 views

How to find the insected area between the two neighbouring polygon features using python programming

1) I am merging the neighbouring polygons based on the area calculation.Sometimes the polygon features are intersected at the edge or at one vertex only so when i am trying to merge those neighbouring ...
1
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1answer
40 views

How to generate random points with minimum distances between points in multiple polygons

I am looking to create random points for a random stratified survey. There are three different categories being surveyed; for each, I have a single shapefile, each containing a number of polygons. I ...
7
votes
1answer
203 views

How to visualize measure values along linestrings in QGIS?

I have a series of LineStringM geometries. The measure value represents slope (or stream gradient) at each point in the geometry. I love QGIS's robust styling options, but I can't find a way to render ...
0
votes
1answer
126 views

Unable to run R in QGIS 2.6 - rgdal unavailable for R 3.1

I'm attempting to use R within QGIS2.6 on OSX Mavericks but cannot get R to run because rgdal is not available as binary for R3.1.2 (see QGIS log output from R execution console below). I have ...
0
votes
1answer
40 views

QGIS - Understanding how to georeference NAIP CCM jp2 images with lat/lon

I'm a very new QGIS user and no GIS expert. I am having trouble getting jp2 images to align with a vrt raster I've created from SRTM images. What I'm trying to do: Overlay SRTM data with ...
0
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1answer
59 views

QGIS 2.6.1 doesn't load python plugins on Ubuntu after upgrade [duplicate]

I have experienced this scenario once before and now today, whenever I updated my QGIS installation on Ubuntu, it didn't reload python plugins under ~/.qgis2/python/plugins when started, only c++ ...
1
vote
1answer
46 views

Loading Vector Layer using python console in qgis

I am using qgis2.6 version and new to pyQGIS. I tried to load a vector file using python console in qgis. I don't know where I am wrong. The layer was not loaded and does not show any error too. Help ...
0
votes
1answer
39 views

QGIS Crashes when I connect to QGIS Cloud [closed]

QGIS crashes when I try to connect to QGIS cloud. I just signed up for the cloud service - still testing out the free version. When I try to connect through the plug-in panel (I use no proxy server) ...
1
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0answers
36 views

How to cut parallelogram with intersecting line?

I have a very specific set of circumstances under which I need to break a parallelogram into 2 pieces. The parallelogram obviously always have 4 vertices and the intersecting line intersects the ...
1
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0answers
40 views

Tiff Raster File slow to Load in Win 7 64 Bit QGIS 2.6.1

I have been unable to load a Geo Referenced Tiff file in 2.6.1, I have found it it will load but takes minutes, It will load quickly in 2.4 It is a Lidar file so it is large, about 14 gb in size, I ...
0
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0answers
23 views

how to use qgis api in runtime program on linux?

I tried to show raster map with symbolic on it in c++ application on linux os. How can i do it with qgis?
2
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0answers
24 views

why in my processing of qgis not exist the module Catchment area (Parallel)?

I have qgis 2.4.0 chugiak and have install processing but in the box of tools not exist the module catchment area (parallel), how to install this module? thank you !!!!
0
votes
1answer
12 views

Combine Elevation Raster and MultilineString to create MultilineStringZ in PostGIS

I want to show how steep a given stream is. I'm using PostGIS and QGIS. I do not have access to ESRI products. I have some ideas, but I'm not entirely sure how to proceed, and some of my assumptions ...
3
votes
1answer
43 views

Why is QGIS rounding off manually added decimal attributes?

I am manually adding a decimal column in qgis and set the width and precision to one more than I actually need (Width: 5, Prec: 5)so the number comes out as 0.XXXXX, but when I save my eidts qgis is ...
4
votes
1answer
93 views

Identifying south facing mountain land, above an elevation, within a slope range, less than fixed distance from major roadways

This odd question comes from believing that such an analysis is plausible in a GIS system. Only, I don't how to accomplish the various discrete steps implied from the Title, nor where to get a topo ...
2
votes
1answer
78 views

QGIS Dissolve tool re-projects and rotates layer

I'm trying to use QGIS (2.6.1-Brighton) to aggregate polygons according to an ID attribute. I'm using the shapefile of school district polygons in Michigan found here: ...
2
votes
0answers
28 views

Trouble merging 2 rasters using qgis

I am trying to merge two rasters using the "merge" tool on Qgis 2.6. Qgis does complete the process, but the resulting image only shows one of the two rasters with the rest of the extent with really ...
2
votes
1answer
46 views

Calling canvas.saveAsImage from script in QGis -Qstring problem

I want to create a processing script that saves the QGIS MapCanvas exactly as it is seen on the screen and then Zip up the tifw and a created PRJ. The existing QgsMapCanvas.saveAsImage()-method does ...
2
votes
2answers
88 views

How to merge same long lat points with different data into a unique one?

I have a layer where there is more than 1 feature for a same object. Imagine i have a layer called signals. There can be up to 10 features in the same place (long/lat) for a unique signal but the ...
3
votes
1answer
33 views

Can QGIS 2.4 follow symbolic links to load data on Linux?

Q. Can QGIS 2.4 [Edit: NOT 2.8, brain-freeze] follow Linux soft links? I want to add a number of raster layers from a store of NED30m elevation data, and thought I'd do it by creating a collection ...
0
votes
1answer
95 views

Web map viewer for QGIS Server and PostGIS

I have succesfully installed and configured QGIS Server. I tried WMS and WFS via QGIS Desktop and it works perfectly. Now i am looking for a web map viewer to display (only read (WMS viewer i ...
2
votes
1answer
31 views

Colormap to grayscale map using QGIS?

I need to export color orthophoto map to gray scale geotiff file using free tools (like qgis) any idea? I tried qgis preview but this does not produce new geotiff file
2
votes
2answers
93 views

Adding new fields to shapefile alters appearance of borders in QGIS?

I am using QGIS 2.6.0-Brighton and I am trying to add a custom field to my layer made from a shapefile of Italian provinces; everything seems fine when I create a categorized views using region codes, ...
2
votes
1answer
48 views

Distance to nearest hub output not correct

In QGIS 2.6, I'm working with two point layers: center of the population per census tract and stores that accept food stamps. I'm using "distance to nearest hub" to calculate nearest food stamp outlet ...