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

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22 views

Is there a way to export entire projects or groups to KMZ?

There is a lot of questions about exporting single files, Im trying to see if there is a way to export an entire group in QGIS to a .kmz file that can be opened in google earth. I know there is a way ...
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0answers
19 views

Display tabs don't appear when files and folders are selected in QGIS?

My setup: QGIS 2.8.1 Wien on OS X 10.10.2 I'm a complete beginner at GIS and I'm having trouble on getting the Param/Metadata/Preview/Attributes tabs to appear in the Display Window. When I select a ...
2
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0answers
33 views

ST_Buffer with segment AND endcap parameters

Making a QGis plugin that buffers a line and I want to declare a high number of segments and a flat endcap. ST_Buffer(geom, 40, 25, 'endcap=flat') This doesn't work with both parameters entered, ...
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25 views

QGIS topology overlap check

I have checked topology rule must not overlap with and i get error The problem is that i have check this many times, and made hole vertex after vertex so it is not possible that these objects ...
2
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1answer
57 views

Clip layer with selected object from another layer in QGIS

In ArcMap, I can clip a layer with selected objects from another layer by using the editor toolbar. I want to do the same operation in QGIS. I want to create holes in the landuse layer by selecting ...
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1answer
25 views

Change name of category heading in legend

In QGIS 2.8.1, I have a SHP layer. In the display it is categorized by one of the fields, "Sannsynlig". In the table of layers and in the legend, it is also identified as "Sannsynlig", as the name ...
2
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0answers
22 views

Black map after attempt to style by column in QGIS [closed]

I'm very new to QGIS and I'd really appreciate some guidance. I have a shapefile of NYC census tracts and 2 csv info files with tract info joined with it. I'm trying to style the individual tracts to ...
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0answers
49 views

How to control QGIS from within Anaconda's Spyder (Continuum Analytics Python distribution) in Windows

I would like to control QGIS from within Anaconda's Spyder, in particular use the QGIS core modules. My config: Windows 7 Anaconda 64x for Python 2.7 Spyder 2.3 Postgresql 9.4 PostGIS 2.1 QGIS 2.8 ...
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1answer
19 views

Where can I find Open feature form under options menu?

Going through the tutorials in the documentation for QGIS and I am stuck looking for a check box in the Options menu. The check box is labeled "Open feature form" and seems to have been moved in QGIS ...
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0answers
10 views

How do you snap polygons as you draw in QGIS? [duplicate]

I need to draw a long row of patient rooms for a hospital. I have the following plugins installed in QGIS 2.6: Rectangle Ovals Digitizing CAD Digitize I want to drag a set of polygons that aligns ...
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1answer
27 views

Is there a solution to glitches when deleting features from Shapefiles on network drives?

We are a small GIS department of 4 folks working with a shape file composed of points. We have local installs (C:) of QGIS 2.8.1 on our workstations, which run Windows 7 x64. The shape file in ...
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41 views

Easy to Install QGIS Server Web Client for Windows

I am looking for an easy to install (.exe file for example) web client for QGIS Server. I found a hard to install software: QGIS Web Client in Windows does not load map But maybe in the last months ...
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0answers
66 views

ECW support on ubuntu 14.04 - QGIS 2.8.1

I've followed instructions for lubuntu 14.04 - QGIS 2.2 ( Answer in Unable to install ECW support on lubuntu 14.04 ), adapting to QGIS 2.8.1. No problem to install packets, but result of gdalinfo ...
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0answers
19 views

How to reset query format in QGIS?

I have a raster layer (wms) that I can query for some info (1). The query window offers different formats for this (2). However when I select "Object", the query result vanishes (3). I looked ...
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2answers
32 views

QGIS modeler - how to extract polygons by multiple arguments?

I'm using QGIS modeler to extract lines by not one, but multiple attributes. For example, I have a road network, and I want to extract only road with character values in field TYPE: value_one and ...
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1answer
52 views

How to read landsat images from Amazon S3 using python?

I would like to read and process landsat images from Amazon using pyton thanks,
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1answer
26 views

Using pyQGIS transform a layer of polygons into a layer of holes inside a bbox

I'm using python in QGIS. I have a layer of polygons (its a result of some earlier dissolving and has no overlapping polygons but some holes and islands in holes etc). I want to build a new layer ...
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1answer
37 views

Resolution problem in QGIS raster

I have a raster file I need to clip. I created a virtual raster which I used to "copy" the extent from in QGIS raster calculator. As a result, I get the raster with the extent I need, but pixel size ...
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1answer
23 views

Cleaning shape file with multiple boundaries defined more than once

I have a shape file which contains a lot of polygons which define airspace. These polygons overlap and this is fine (e.g. different airspace configurations for the same airport). My problem is that ...
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0answers
31 views

QGIS Map Export in PDF / PNG format - overlapping layers - not printing

I am using map composer in QGIS 2.8 (Wien) where the legend layer overlaps the Map layer without any transparency. While I export the map to PDF or a PNG, the legend layer is not printed. What ...
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1answer
33 views

QGIS bar chart with labels

I am trying to get a simple bar chart on my QGIS 2.6 map. I have done that with diagrams. It seems to me it is not possible to add simple values to each bar (say there are three bars at a point). I ...
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0answers
24 views

Selecting polygons using another polygon? [duplicate]

Hi, How is the best way or fastest(if there is) of selecting polygons of a different shapefile using a polygon of another shapefile. exercise example: i want select all the light brown polygons ...
5
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1answer
155 views

Why are all tiles white when using the OpenLayers plugin?

I installed the OpenLayers-Plugin and set the CRS to EPSG:3857. When I go to Web / OpenLayers plugin I get the menu with the various maps, but whatever map I choose, all the tiles are white. The ...
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1answer
25 views

How can a QGIS user plugin reflect the events of UI?

I am developing a plugin for QGIS 2.8 which uses the data of the active layer. It has a dockable window. When the user changes the active layer, the contents of the plugin window's widgets must ...
2
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1answer
74 views

Conditional Value Map widget in QGIS

I am looking for a way to implement conditional value mapping in QGIS. This means that the values available in attribute number 2 depend on the value provided in attribute 1. Example: If the user ...
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1answer
44 views

Merging small area units [duplicate]

I am working with population data organised in parish units for the whole of Denmark. Many parishes are very small (ie <500 inhabitants compared to a median of around 1500) so I plan to merge these ...
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0answers
20 views

QGIS/GeoJSON: Dissolve featurecollection consisting of polygons and multipolygons into a large multipolygon

I've read this question. I would like to know how to do this in QGIS. I have a Geojson file with a featurecollection, starting with: ...
2
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1answer
52 views

How to change no data value from -32768 to -3.40282e+38 in raster in QGIS?

I am trying to change the null values of a raster from -32768 to -3.40282e+38 in QGIS. I tried using warp tool setting the no data values to my desired number but it did not change it. Then I used ...
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2answers
92 views

Is there any library can perform polygons buffering/ inflating/ merge/ overlap at server side?

I have a set of polygon data express in lat long. I would like to perform some tasks (polygon buffering, inflating etc etc ..) in server side and output the result to client side (client is a web ...
0
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1answer
30 views

QGIS GPS not editing offline database

I have a set of layers from PostGIS that I have converted to offline. I am attempting to edit them via GPS. If the layer is point data, then I can add in that data without issue. However when I go to ...
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1answer
33 views

How to sum up values within grid polygon in QGIS?

I have a grid full of hexagons that I am trying to bin points. However, instead of using the Vector > Analysis Tools > Points in Polygon which counts the number of point inside each hexagon, I'm ...
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2answers
21 views

Should I be able to open personal DB converted to MSSQL as a MSSQL Layer?

I'm feeling like this should work, but I'm banging my head against the keyboard, the documentaion and the google as I can't find any examples to follow for MSSQL. I have 3rd party data only in an ...
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1answer
68 views

PyQgis, styling vector layers in different canvas

I'm developing a QGIS plugin and I need some help with styling layers in different canvas objects. In my dialog window I've got two QgsMapCanvas objects canvas1 and canvas2. Layers from registry are ...
1
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1answer
39 views

PostGIS: Is it possible to identify overlapping polygons in the same layer using their geomteries?

I have a single table containing the geometries of ~3 million polygons and I am looking to calculate the number of polygons that overlap with another. I know that you are able to do this in QGIS ...
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0answers
20 views

Generating regularly spaced sample points in qgis based on ratio of area

this is my first post on Stack Exchange. The question I have involves generating sample locations in irregular shaped polygons in qgis. In my situation, there are often many polygons in one shapefile ...
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1answer
18 views

QGIS Grid Union Issues

I am trying to create a choropleth map of ice concentration over Lake Erie. I have data for all the lakes (I can clip it all at the end), which are in a point shape file. I have laid a grid over the ...
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0answers
44 views

QGIS's “Points in Polygon” counts zero in every census tract

I am mapping the location of incidents of asthma using QGIS. I would like to count how many points are in census tracts to better understand the areas where asthma occurs most frequently. My map ...
0
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1answer
32 views

QGIS add layer not working

I have QGIS 2.8. I open up the database manager, connect to PostGIS, and then execute a query. The resulting query has an id column, a name column, a geom column, and a membership column. I click on ...
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2answers
36 views

Why QGIS Raster clipper does not work on reprojected layers?

I try to clip a hillshade raster and I get this error. The hillshade was the result of a reprojected DEM from WGS84 to WGS84UTM. When I to clip the hillshade or even the reprojected DEM, I get the ...
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1answer
21 views

vertical and horizontal scales on raster

I have a raster image which is a log. What I like to be able to do is to extract the X any Y points from the raster. That are in two sets of units The ideal outcome would be an output of an x and ...
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2answers
75 views

Convert a tiff Float32 image to 8bit tif (or jpeg) image using GDAL and Python

I need to convert a Float32 tiff image to 8bit format in order to display the image in a web page. In order to do that I need a jpg image but this conversion is not correctly done with GDAL because ...
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0answers
35 views

How to Transform from Pixel Coordinates (LCC Projection) to Lat/Long?

I want to transform pixel coordinates from a vector graphic (as .svg) to long/lat values. My vector graphic represents germany and consists of multiple polygons. I've already successfully written a ...
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2answers
60 views

QGIS Viewer, QGIS read only?

Is it possible to create a read-only project in QGIS? Or is there any viewer software available for QGIS project file? What I am after is a read-only project that shows and keep labels and rendering.
2
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2answers
103 views

How to manage label spacing/density in QGIS?

How to manage space in between labels (or density)? I would like to have less labels in order to have more space in between. The label order is not important. I would like to precise is just for ...
3
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1answer
62 views

How to summarize a column in QGIS field calculator

I have data with a column containing a number value, and I want to divide the value of each feature by the total sum of all the values in the column (to get a percentage). So I would like to know if ...
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0answers
18 views

WMS problems Qgis server with postgis

I have installed qgis and qgis server on a windows server. My plan is to use qgis server to generate a wms. It works fine when I'm using shape files in my qgis project, but when I'm adding a postgis ...
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0answers
34 views

QGIS 2.8.1 crashes when connecting to Personal Geodatabase?

I have a problem connecting to a ESRI Personal Geodatabase. I used to be able to connect to the database using QGIS 2.6.1, but I did some editing to the database in Arc and after that I was unable to ...
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0answers
30 views

Never get the information about obective interpollation and optical interpollation

I have point data want to interpolate it and convert it into 3d grid format but i am not get any proper information which interpolation i have to used objective / optical. please let me know any ...
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28 views

Catchment area calculation

I have a conundrum. I am trying to shortlist optimal physical locations in my county for developing recycling centres that serve the population. I have a vector point layer of the centre point of ...
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1answer
41 views

How to show percentiles in Qgis?

I have a polygon layer with several fields, like: population, wage, age, etc. I would like to show the percentile value for those fields. How can I do that in an automatic way with QGIS 2.6.1?