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

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How can i upload two CSV file in QGIS Desktop App?

If I am using single file upload code it will work fine. self.dlg.lineEdit.clear() self.dlg.pushButton.clicked.connect(self.select_output_file) But I want to add more than one files it will give me ...
2
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0answers
51 views

QGIS use item id in print composer for relations

i'm trying to use the item id in the print composer of QGIS to build relations. for example: i have a label with the text "test" in it and it has the ID=label1 -> now i have a second label in my print ...
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1answer
210 views

How to style a vector layer in QGIS using hexadecimal color code stored in attribute?

I have a polygon shapefile storing hexadecimal color codes in a specific attribute. gid | label | color ---------+-----------+------------ 1 | Crops | #FF5F2C 2 | Forest ...
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0answers
102 views

Loading map (*.mxd) from ArcGIS for Desktop into QGIS? [duplicate]

I created a map based on a DEM in ArcGIS (with Spatial Analyst). The office I worked together with, now wants me to add some extra layers into my map for further use. The thing is, my student licence ...
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0answers
194 views

SAGA version with QGIS 2.10

I want to know which version of SAGA is used with QGIS 2.10. I developed a standalone application which uses QGIS inside. I have problems using SAGA algorithms. SAGA is well installed but I found that ...
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2answers
431 views

How to make a circular polygon in QGIS?

I am trying to make a floor plan for my office, have managed to make all of the rectangular components (e.g. the rooms) however some of the desk layouts are circular and I haven't been able to work ...
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2answers
106 views

How to create a polygon grid with un-even spacing between research plots?

I have an orthomosaic of a crop field with small research plots (3.8 X 1.44 m and 0.22m b/w plots and 0.50m b/w range spacing). I would like to create a polygon layer using this information. After ...
4
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1answer
108 views

How to visualize texture along borders of multipart polygon

I came across this map and would like to replicate the textured styling found along the borders. I'm starting with a multipart polygon but my process has perhaps too many steps. I'm using QGIS 2.8.2. ...
1
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1answer
83 views

Need help making polygons from lines in QGIS

I am trying make a layer of buildings, divided into apartments, by making polygons from crossing & intersecting lines in QGIS. When I use the vector/geometry tools/lines to polygons tool, I get ...
1
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1answer
26 views

Setting Transparency in .IMG format

Is there a way for QGIS make just the black value (255,255,255) on an .IMG format file transparency. Right now their transparent option makes the whole image transparent.
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0answers
180 views

Where to find Advanced Python Field Calculator qgis sintax documentation

I am trying to follow some tutorials using Advanced Python field calculator, but when I enter the formula value = $geom.area() / < area> I get syntax error as in picture, while if I substitute ...
6
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1answer
320 views

How to create an Atlas based on point attributes?

Essentially I am wanting to produce an atlas based on a categorical field in a point layer. i.e. I have a point layer of childcare providers with the categorical field "Provision". I've categorized ...
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0answers
157 views

How to wait for mapCanvas render before taking a screenshot?

i am trying to iterate over a large list of features and making a screenshot of the selected feature. My problem is that it seems to be a delay between the refreshing of the canvas and the taking of ...
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0answers
353 views

How to obtain an euclidean distance raster from a vector file in QGIS?

I'm trying to obtain a raster of Euclidean Distances from a vector layer I have of a river in Spain. I did it very easily with ArcMap using Euclidean Distance, but I don't know how to do it in QGIS. ...
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1answer
272 views

Spatial join of a single point to multiple polygons

I have a point layer which I want to spatially join to a polygon layer (bring in the attributes). This works fine unless there are overlapping polygons, if so the QGIS spatial join tool will only ...
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0answers
79 views

How can I upload CSV file in QGIS Desktop App?

Please see link : http://www.qgistutorials.com/en/docs/building_a_python_plugin.html I am using the same process for uploading a CSV file in a folder but it gives me an error. I am using this code: ...
1
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1answer
65 views

Styles not applied when using QgsMapRenderer

Using pyqgis, i am trying to export some maps as images using QgsMapRenderer. Here is the layer/style setup, both load correctly: lyr = QgsVectorLayer(uri.uri(), 'Report', 'postgres') styleload = lyr....
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0answers
70 views

Where can I download a raster dataset with the latitude and longitude of each pixel in geographic projection?

I want to do raster calculations in QGIS based on the latitude and longitude of each pixel. The calculations will compute the area of the pixel, but also do other calculations for various projections ...
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1answer
187 views

Publishing QGis project on Geoserver

Is there a way to prepare a project on QGis with many layers and to publish it under wms service on Geoserver? Thank you for responses
1
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1answer
29 views

EasyCustomLabel in QGIS do not resize the labels

I use EasyCustomLabel to move some labels, but if I try to change the dimensions of the chars I cannot view any changes, both in the work and in the printing sheets. I use QGIS 2.6.1.
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0answers
58 views

How to fill a symbolLayer with a custom texture?

I have this code : pLayer is a QgsVectorLayer * QgsFeatureRendererV2 * lrenderer = pLayer->rendererV2(); QList<QgsSymbolV2 *> lSymbols = lrenderer->symbols(); QgsSymbolLayerV2 * ...
0
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1answer
232 views

How to create soil-type maps using QGIS

I am trying to create a soil-type map of an area from point data using QGIS. I tried interpolating the data, since soil is continuous. I did this by allocating a number to each point type and then ...
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0answers
62 views

How to react to network events

I am in the process of writing a Plugin which should react to some data (XML-Format) sent via a socket connection. Since I have never worked with IPC in terms of python before and my knowledge of IPC ...
2
votes
1answer
106 views

How to display attributes of features intersecting the Atlas feature in a Print Composer label?

Is it possible to edit labels with python or an expression? I have an atlas layer and a shape with countries. the atlas layer has several features and each feature intersects with several countries. ...
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214 views

QGIS: calculate slope of line-segments

Using QGIS, I'd like to achieve the same as in question calculate-slope-of-street-segments. I have a shapefile with lines (rivers) and a DEM. So I suppose the best way is somehow like this: 1 - ...
2
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0answers
180 views

QGIS spatial join - join all features, not just one

I'm trying to do a spatial join of a feature on a polygon layer (p1) that intersects with two features of another polygon layer (p2)) via QGIS. What I want: get the attributes of both features of p2 (...
3
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2answers
219 views

Limiting list values based on previous field in QGIS Forms?

Looking for assistance to set up appropriate configuration to enable drop-down lists values to be filtered based on a previous value. Basically, I have a 3-tiered categorisation structure to one of ...
0
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1answer
39 views

looking for documentation about exploiiting OSM file with c++ API

My application is written in QT4.6, i use the C++ API of QGIS 2.8.2 i had to read and display OpenStreetMap in my canvas in my application so, i am looking for some documentation or tutorial for ...
1
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1answer
220 views

Performing linear regression of NDVI raster time-series using QGIS?

How can I perform linear regression of NDVI raster time-series images using QGIS? I have NDVI images for seven years to perform vegetation trend analysis. Each year has two to four different image ...
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0answers
88 views

How to cut big shapefile into several smaller shapefiles?

I'm converting my shapefiles to gpx files to use them in garmin gps, but if the shapefile is too big, I lose data in the conversion. I get a gpx with holes in and I cannot work with it in the field. ...
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0answers
37 views

Capturing line version 2.10

I'm a beginner (as in complete noob) user with version 2.10. I'm trying to digitise some rivers from a raster layer but can't find the "Capture Line" tool which the tutorials and resources show as ...
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0answers
73 views

How to export shapefiles and other attributes to KML using QGIS?

Is it possible to include all the attributes in the table of a shapefile when exporting it from QGIS to KML? I want to view all other data inside my table in Google Earth.
1
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1answer
34 views

Problem trying to build a stand-alone QGIS application with Unbuntu Trusty system

I'm currently reading the "Building Mapping Applications with QGIS" Book and I'm stumped when I try to set my paths in Ubuntu. The first command works fine: export PYTHONPATH=~/usr/share/qgis/python/ ...
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1answer
161 views

Calculate slope of line based off of point layer

I have a line feature class that needs to have its slope included as a field. I have a point layer that contains points and their elevations for the start and end of the line segments. How can I ...
0
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0answers
134 views

How can I convert Decimal to DMS for QGIS reprojection?

I have the following Lat/Long which I converted to DMS using the following calculator: Decimal DMS -96.2 96 12 0 -95.13 95 7 47.9994 29.3 29 18 0 29.98 29 58 55.1994 https://www....
2
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0answers
118 views

how to orthogonalize building outlines

I'm looking for a way to orthogonalize building outlines which I've extracted from a high-res DEM. I'm using the FOSS GIS stack (QGIS, GRASS, SAGA, PostgrSQL, PostGIS) and can code in Python (or Java)....
1
vote
1answer
73 views

pgrouting: function driving_distance does not exist

I tried to run driving distance function but got error. function driving_distance(unknown, integer, integer, boolean, boolean) does not exist LINE 1: SELECT * FROM driving_distance(' ...
1
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0answers
78 views

How do I make atlas with same pages but different layer sets?

I have a project in QGIS with multiple layers that I have to render separately. E.g. parks and distances to them (their buffers), travel time isochrons (interpolation with colors), density heatmap, ...
0
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1answer
109 views

Calculating Distance and Time on a network without the use of ArcGIS Network Analyst

I'm trying to calculate a distance and time for walking commuters (about 30,000 records) on a street network (NYC Lion). I have a starting and ending address for each record that have been geocoded. ...
0
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2answers
52 views

QGIS Processing Scripts Shared Code

I'm on a Windows 7 machine with QGIS 2.8 installed via OSGeo4W. I'm developing several processing scripts that make use of a few common pieces of code. Rather than maintain the code in each individual ...
2
votes
2answers
114 views

Critical facility pipe connections in python

I'm trying to find a way to determine pipeline connections located downstream a critical facility and score how far those connections are from the facility. Is there a way to accomplish the above ...
0
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2answers
96 views

How to measure the sum of the areas of each class in QGIS?

The project has a layer with several groups of polygons with different weights. Each group is associated to a weight. How can I get the sum of the area of each group?
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0answers
21 views

how can i change property of a symbol using qgis 2.8 c++ api

i have an application written in QT 4.6, and use the C++ API of QGIS the application will display the data of the s57 file in a MapCanvas i managed to read the file but how can i , for a specific ...
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1answer
97 views

Finding the date of acquisition of Google maps in QGIS

How do i find the date of acquisition of the Google map on QGIS? Please help.
3
votes
2answers
678 views

Standard color mapping for NDVI?

I am currently generating some NDVI imagery using QGIS 2.8.2 and there are a multitude of possible color map scales that can be applied to the imagery. I was wondering if there was a preferred or ...
0
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1answer
67 views

Create primary and foreign key on Spatialite

I try to create a database on spatialite (for various reason, I can't use PostGis). I need to link a table to another one using a foreign key. The problem with spatialite is that it is not possible to ...
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0answers
71 views

SSL-Authentication failure

i try to include a wms-map into my current project. When i try to connect qgis 2.4. gives the failure-output: Attributes-request denied - failure in the SSL-protocol procedure. ArcMap 10.2 says: ...
1
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1answer
184 views

How to get the coordinates inside the polygon using python

I have a polygon and using this code snippet we can get the coordinates boundary of the polygon. canvas = qgis.utils.iface.mapCanvas() aLayer = canvas.currentLayer() coord = feat.geometry().asPoygon()...
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0answers
58 views

Nearest neighbour / spatial join with attribute condition

I have 2 point format datasets I wish to schematically join (manholes & gullies). I am content that I can join them by nearest proximity alone using e.g. NNJoin plugin. What I would like to do ...
1
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1answer
186 views

Does anyone know a way to do a supervised classification on a google maps image to show only hedgerows? [closed]

I would like to then use the hedgerows by bringing it into QGIS as a layer. I need to know what software to use and the method to make such a layer? I would like to use a google earth image in Grass ...