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

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27 views

“Impossible to engage a segment in the current layer”

How can I fix this ? My problem is the red "x".
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0answers
121 views

Are QGIS and Neo4j a good match?

I'm having some problems with Neo4j Spatial and OSM. http://stackoverflow.com/questions/31523109/how-to-run-neo4j-with-osm-and-neo4jspatial I'm considering using QGIS + Neo4j is that possible? Any ...
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1answer
54 views

Connect a point geometry with a graphics label on a map

I am creating a map with traffic signals in a city. Creating a point layer and adding my symbols as SVG mark is appropriate for 90%. But some signals explain alternativ routes used during events. ...
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2answers
172 views

How to sum values of overlapped pixels in thousands of rasters layers and clip it using a polygon in QGIS?

I have a lot of rasters files (more than 6000), each one represents the presence and absence of a species (1 for presence and NoData for absence). The set of rasters covers the whole Latin America ...
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1answer
418 views

Determine start/end points for line slope calculation [duplicate]

This is a follow up question based off of this question. I have a line feature class representing storm drains and a point feature class representing where storm drains are connected. The point ...
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2answers
206 views

PyQGIS Use of predefined color ramps

I´m trying to apply one of predefined color ramps to a categorized field in a vector layer. To do this, I'm using the code below suggested by Irssvt in another post. However, I cant´t see the result ...
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0answers
33 views

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 ...
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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
182 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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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
192 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
366 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
102 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
104 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 ...
1
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1answer
77 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
163 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
309 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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147 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
297 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. ...
1
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1answer
243 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
75 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: ...
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1answer
60 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 = ...
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0answers
67 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
160 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
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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
53 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 * ...
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1answer
207 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 ...
1
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0answers
59 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
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1answer
100 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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0answers
202 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
174 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
203 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 ...
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1answer
38 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
207 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 ...
0
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0answers
86 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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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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72 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
32 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
154 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
123 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 ...
2
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0answers
110 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 ...
1
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1answer
62 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
75 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
101 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. ...
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2answers
51 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
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2answers
112 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 ...
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2answers
87 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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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 ...
1
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1answer
86 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.