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

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3 views

Remote sensing Classification and texture analysis compared with QGIS zonal statistics

Some back round: Using Geomatica to analyse suburban spectral signature in Las Vegas. Ran a texture analysis on all band images. Combined texture bands with original image bands to run an unsupervised ...
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0answers
4 views

Toggle layers on print composition

I want to use QGIS to make several views of bold colors for one same map. I've been using the layers in order to keep one on top of another. How could i make a composition on the print composition ...
1
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0answers
6 views

Change detection between two Landsat scenes?

I want to do time series analysis and find change in NDVI. I have rasters where each pixel is represented by some value at a time. Also I have same thing but represented by points. And I would like ...
1
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0answers
9 views

How do I make a hexgrid in QGIS with cell identification numbers

I'm getting started with QGIS as part of my interest in military science and wargaming. I'm running into a problem adding identifiers (column and row) to the hexcells that I've created with mmqgis. ...
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0answers
15 views

Using proj to convert EPSG:2263 to WGS84

I have input data in EPSG:2263 with X and Y coordinates such as: X,Y 987043,206407 982441,212359 990907,209020 (these locations are within NYC). I need to convert these to WGS84. Using QGIS if I ...
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1answer
29 views

Merge shapefiles heatmap

I have to merge few shapefiles into one and create a heat map out of it in qgis. I'm a first user of the QGIS, I tried to do it there: vector-management tools-merge files into one, but it kept to make ...
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0answers
11 views

Add individual fields to delete-log-trigger when deleting PostGis-Objects via QGis

I am using a PostGres Database with PostGis extension (on Windows). QGis serves as a client to access (visualize and edit) certain database-tables. I need to create a delete-log-table that saves all ...
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2answers
16 views

Load USGS DRG into QGIS

I'm trying to load some DRG data from the USGS into QGIS. The source data uses UTM coordinate and I can't seem to get it to overlay with WGS 84 vector data. I (think) I've followed the recommended ...
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0answers
18 views

Adding QGIS feature that shows coordinates and scale into custom application

I'm writing a standalone application using PyQGIS and I'd like to add the QGIS feature that shows coordinates and scale as the cursor hovers over the map. I need to know this mainly in case of ...
3
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0answers
22 views

How to develop QGIS Plugin to fully run Spatial Queries With PostGIS?

I'm developing a QGIS plugin that fully run spatial queries with PostGIS. Actually I developed all spatial queries wish need some adjustment. I'm looking for some ressources or documents to know how ...
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3answers
34 views

Rotating labels in QGIS 2.8.2

I have a question concerning label placement in QGIS. I'd like to rotate every label by 180°. Therefore, I set the rotation value to 180 (I've tried different ones as well as different variable types) ...
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0answers
13 views

GML geometries are not rendered

I tried to view a GML file and I have a problem with viewing of polygons from a feature type ps:ProtectedSite with QGIS. This feature contains a MultiSurface with a surfaceMember with a ...
3
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2answers
29 views

How to fix the error between two coordinate systems?

How do you think the shift of line is due to morphological change of river? Or it is due to deviation between two coordinate systems? Please point out !!
2
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1answer
26 views

Layer Order panel seems to be broken in QGIS 2.10, it duplicates layers

I'd like to just confirm that a problem I am having in QGIS 2.10 is not unique to me. I am using the Layer Order panel to control the rendering order of layers in my projects, it's very useful when ...
2
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1answer
18 views

Merge and export two layers that utilize blending modes

I have a new question that I'm trying to solve. Spent more time than I can to admit trying to come up with a solution that doesn't require bringing the layers into Photoshop or the GIMP (which would ...
1
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1answer
24 views

Can I use TIFF files for zonal statistics in QGIS or ARCGIS?

I am completing a remote sensing paper and am doing most of the work in PCI Geomatica, where I have 2 separate files. One from running a texture analysis algorithm containing 6 band layers from a ...
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1answer
32 views

How to place coordinates points on a vector layer?

I have got GPS coordinates collected from a number of farms in my country (Malawi). But when I plot these GPS coordinates on a vector layer (my country map) using QGIS, the points are falling outside ...
2
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0answers
14 views

Compare similar lines and update layers

Here there are two layers with the representation of the streets and the idea is: We want to update the most recent layer (with the red line) with some of the data storaged in the other one (the light ...
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0answers
15 views

What is the correct way to run a python script in QGIS Open Project macro?

This code (answer from @gcarrillo about other question - Is there any way to freeze the layer names in the TOC?) runs fine on python console and inside a plugin. But now, I tried put it within the ...
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0answers
25 views

Minidump on exit in QGIS (2.8.2- Wien) 64-bit version when using GDAL in plugin

I am working on a plugin for QGIS that is working fine on 32-bit versions but I am having some problems while using it on the 64-bit standalone installation package. I have tried on several machines ...
2
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2answers
112 views

Where to download QGIS 2.10?

Is QGIS 2.10 Pisa for Ubuntu/Windows already available?
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0answers
19 views

How to call the Qt UI of a script?

I'm pretty new in the python world, and I'm working with the python console inside QGIS (Master version on a Debian machine). I have written some scripts, all of them are in the same directory (e.g. ...
2
votes
1answer
34 views

some shp to dxf converted lines don't show in Autocad

I have a group of vector files that I intend to convert to "DXF" format. But after the conversion, only contour lines(white lines in the red polygon) are not displayed in Autocad. I read some related ...
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1answer
27 views

Print composer - legend - graduated

I have a map with graduated symbology, with 328 unique values. I would like add a legend to my map (as in the picture), illustrating that light blue indicates low values and dark blue high values. I ...
1
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1answer
26 views

QGIS: drag zoom via keyboard shortcut/ mouse wheel?

to zoom to a rectangle in ARCGIS i always clicked and held the mouse wheel while pushing the control key. This was a very efficiant way for me to navigate through a map. Is there anything similar in ...
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0answers
33 views

QGIS - Simplification process creates a new polygon - how to avoid it?

I am trying to simplify a layer made of polygons. I have used different methods but the new simplified layer has a polygon which intersect with itself, thus creating a "new" polygon. Please see ...
2
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0answers
20 views

QGIS QgsLayerTreeGroup signal “currentLayerChanged”?

In a pyqgis context, I use the "currentLayerChanged(QgsMapLayer *)" signal of the QgisInterface class to do something when the current layer is changed, but I need now to do the same when I select a ...
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0answers
11 views

How to Change Precision of Export / Add Geometry Columns field

I would like to display the coordinates of a number of points on a map. I can use Vector > Export / Add Geometry Columns which adds coordinates to 6 dp. However as I am using a UTM-type projection ...
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2answers
21 views

QGIS Editing: move - both - nodes after Cut has been performed

I just ran into unexpected behavior while editing a polygon shapefile in QGIS 2.8.2. Scenario: A polygon: Then I cut that polygon into two seperate poygons: Then I use the Node Tool to move a ...
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1answer
29 views

How to completely uninstall and remove QGIS 2.8.1

I want to uninstall and completely remove QGIS installation from my computer(windows vista). I have uninstalled it and when i try to reinstall it says it is already installed on the system.
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0answers
17 views

QGIS import OpenAIP

I have files from OpenAIP (http://www.openaip.net). How can I import them ? Format available are : .aip .cup .dat .aip is xml file. For point : <OPENAIP VERSION="960678" DATAFORMAT="1.1"> ...
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2answers
18 views

Embed Sound in Leaflet Popup with QGIS

I was wanting to embed some animal sounds in a leaflet map my son and I are creating. Have images embedded, but would like sounds in the popup if possible. Like embedding images, can this be done ...
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0answers
15 views

How to create new field using the values of one attribute column multiplied by a constant number in Qgis or ArcGIS [duplicate]

I have point data that has a small length attribute - I want to times this length attribute by a constant number (I need to trial a few different constants) to find the diameter of a protection zone ...
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0answers
19 views

QGIS dissolve by attribute and retain primary polygon attributes

I have a parcel shapefile. Many of the parcels have been combined over time, but the shapefile still represents the original parcel boundaries. The attribute table has a field for the original parcel ...
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1answer
29 views

Loading GeoServer WMS raster layer in QGIS Python console

I am using the following snippet to load a raster layer deployed under wms service using geoserver, in qgis python console. I am getting False output. Any idea? registry = ...
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0answers
12 views

PyQGIS Standalone Crashes python.exe when zooming out too far / Process finished with exit code -1073741819 (0xC0000005)

I have the following PyQGIS Standalone App which is working fine so far. One little problem is that if I zoom out to the MaxExtent(by scrolling the mousewheel) the app crashes python.exe so that the ...
2
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1answer
24 views

Error: Algorithm not found (QGIS)

I wrote the following code using QGIS'API. import os from qgis.core import * import qgis.utils prefix_path = os.environ['QGIS_PREFIX_PATH'] QgsApplication.setPrefixPath(prefix_path, True) ...
2
votes
2answers
39 views

Easy Custom Labeling tool: How do I remove label arrows?

I am labeling a lot of features and the Easy Custom Labeling tool is helping me to move every label to the desired position. I also like that the tool adds arrows for labels that I moved but sometimes ...
2
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0answers
25 views

Can you load WFS uncached in QGIS

I think this might be a bug, but we've just installed QGIS 2.10 and the WFS seems to be working strangely. When you load a WFS which is not cached the system loads all the visible features as ...
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1answer
13 views

gsb projection file for qgis under MAC OSX

I'm trying to create a new projection inside wgis. The projection includes a gsb file. With the Windows OS is easy to implemnet that: you just need to place the gsb file inside the ...
2
votes
1answer
30 views

How to add a message bar to custom canvas?

There is a simple code to add message bar to main window in QGIS: iface.messageBar().pushMessage("Hello","World") My question is how to add bar to my custom canvas canvas = QgsMapCanvas() in ...
2
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0answers
46 views

Remove multiple fields from multiple shapefiles using a python script [duplicate]

I'm using the python console of QGIS 2.8.1-Wien. I have a shapefile with many fields in the table that I want to remove them. I tried to use this geoalgoritm as: ...
-2
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0answers
49 views

need information about openstreetmap (osm) [on hold]

I am looking for information or code sample to use OSM map i had to use the c++ api of qgis to write a library of function for a complex application. the language is c++ , i have no choice , no python ...
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0answers
18 views

import qgis.core problem with QgsFeature and QgsGeometry ImportError: DLL load failed: The specified procedure could not be found

I've tried several previous answers to similar questions - no luck. I've tried everything, nothing seems to work. This is the error I'm getting Traceback (most recent call last): File ...
0
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0answers
13 views

Qgis Time manager raster error

I would like to give a shot to the Time manager in Qgis with some raster datasets. I load 2 rasters (both single band, 32bit float). I add the first one in the Time Manager window with the start ...
0
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0answers
12 views

How to graph a line given a great distance (e.g. 100km) and the angle?

I'm new to QGIS and I'm trying to graph subduction zones and I was given the starting point (in latitude and longitude), the length (in km) and the angle (in deg). How is it graph correctly? I tried ...
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1answer
29 views

How to measure the distance between multiple points and multiple polygons?

I'm trying to find a quick and accuarate way to measure the distance between 3 survey sites and all the designated sites within 10km. The survey sites are on a point vector layer and the designated ...
2
votes
1answer
28 views

QGIS Heatmap values change when imported into ArcMap?

I am creating a heatmap layer from QGIS and importing the TIFF into ArcMap. When I import the file into ArcMap I notice that values are different. For example the max value in QGIS is 8.92454, but ...
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1answer
16 views

Semi Automated Classification plugin (QGIS) error when trying to create ROI

When I try to create a new ROI through Semi-Automated Classification plugin (SCP) for QGIS, I keep getting a message saying: "It appears that SciPy is not correctly installed. Please, see this page ...
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0answers
20 views

How to remove las2dem streaks from raster dem

I've created a series of DEM files using the las2dem tool from LAStools, however since I don't have a licensed version they have black streaks running across them. Does anyone know a good method for ...