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

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116 views

Add Vector Layer - Database OODBC does not work

What I am trying to do: Add a vector layer from an remote Oracle database. Platform: Linux Red hat 7 Database: Oracle 11g Connectivity via unixODBC Oracle Description: I tried to add a vector layer ...
2
votes
2answers
705 views

Attempt to install QGIS 2.8 on Ubuntu 15.04 installs old version instead

I previously had installed QGIS 2.8 with the GRASS plugin on Ubuntu 14.04. Through a chain of events I ended up having to do a clean install of Ubuntu 15.04, and am attempting to re-install QGIS 2.8. ...
9
votes
2answers
800 views

How to refer to another layer in the field calculator?

Is there a way to select an attribute from a polygon layer and insert the value into a virtual field of a point layer using "within" in the field calculator? CASE WHEN within($geometry, ...
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0answers
46 views

How to remove covering lines? [closed]

I have a shape file where there are polygons perfectly fitting, i created contour lines from all of the polygons so i have a shape containing only the lines. My problem is as the polygons were ...
2
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0answers
40 views

QGIS 2.8.1 (Windows 64bit). Setting snapping to the “decoration” grid?

I was wondering if anyone knew of a way to snap digitizing to the grid you can create in View>Decorations>Grid? I can't see anything in the manual or the menus so I am thinking there probably isn't ...
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1answer
95 views

QGIS geolocate a DBF file with another point layer by matching field

I have a DBF table and a SHP with points. I want to geolocate the DBF file using the points layer. Both match in a field called "unificationstring". I know how to do it in postgis but how can this be ...
1
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0answers
73 views

How to interpolate a Raster DTM

I have a GeoTIFF DTM produced from Agisoft Photoscan at 0.05 m resolution. However the interpolation used by the program to remove the riparian vegetation has used points from the channel, thus ...
2
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0answers
122 views

clipping raster changes raster values?

I am working with BIOCLIM temperature/precipitation layers and I have noticed that when I clip the global raster down to a specific region, something happens and the raster value at a specific point ...
2
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2answers
179 views

Getting currentfeature's color in Expression Builder of QGIS?

In QGIS Expression builder. I want to obtain the color code of the current feature. I mean: My layer contains lines, each one is painted with a different color. Now I want to assign that color to ...
1
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1answer
323 views

Display different symbols in QGIS using Point Displacement renderer

How to display different symbols (not different in size, different in shape and color) on the same point in QGIS 2.8 using Point Displacement renderer? I want my layout with symbols around the ...
2
votes
1answer
145 views

QGIS 2.8 OSM download with overpass fails

When trying to download OSM data in QGIS 2.8 I am using a layer to provide the extend for the requested data. The extend basically covers all the countries that share coast line of the Baltic sea (...
2
votes
1answer
96 views

Understanding QGIS scale dependent visibilty?

I cannot understand why the scale dependent visibility function does not want to work in QGIS. I'm using the latest version (2.8.1 Wien) and want to insert diagrams (pie/histogram) to illustrate ...
2
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0answers
52 views

QGIS: Edits in attribute table are not updated in Postgis database. Why?

As the title say. I edit values in the attribute tables of my QGIS project but there is no update to the database. I refreshed in QGIS as well as the database. What else do I need to do?
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0answers
94 views

How to convert poly-line contour feature class into heat map displaying heights [closed]

I'm looking for a way to be able to convert contour data (as lines) into a heat map that would display the data warmest at the highest points and coolest at the lowest. I have access to QGIS, ArcMap ...
1
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0answers
74 views

Projections way off on data imported into QGIS?

I have elevation data as a .shp from the USDA ARS and Hi-Res Orthoimages (Mystery Projection (UTM 15N?)) from the USGS website as geoTIFFs (plain NAD 83). I am trying to project all of the images ...
2
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0answers
57 views

Show dimensions on polygons

I have a shapefile that contains all of the property parcel lines in King County, WA. We are currently displaying this data through mapbox on our site with no issues. We would like to be able to show (...
2
votes
2answers
436 views

Create circle shapefile vector in QGIS

Is it possible to create a circle shapefile feature in QGIS, like it is possible to do in ArcMap? I am trying to digitise a map wich features roundabouts, which I'd like to be part of the same ...
1
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0answers
29 views

assign text values to selected subset in the attribute table in QGIS [closed]

I am using QGIS and I would like to generate a new string of text in the attribute table for a selected subset of features in a vector file. I cannot find an operator in the field calculator to ...
1
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0answers
44 views

Accessing elements Linestring and points from a DGN file and displaying both layers on QgsMapCanvas

I am using PyQGIS APIs to develop a standalone application which currently display's map data layers on QgsMapCanvas from .shp, .tif, .dgn files. I am able to do it for .shp and .tif but not for .dgn ...
1
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0answers
51 views

Shaded KML overlays on OSM tiles in QGIS?

This seems simple - but the solution is escaping me. I have a series of dynamically generated KML files describing simple, shaded polygons, with each polygon having a slightly different (externally ...
2
votes
1answer
47 views

Reproject X coord value in Shapefiles

I convert Bavarien NAS-Data (DHDN 3 Degree Gauszone 4) via ogr2ogr into shapefiles: "C:\Program Files (x86)\QGIS Wien\bin\ogr2ogr.exe" "ESRI Shapefile" -skipfailures Entenhausen.xml This seems to ...
1
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0answers
18 views

QGIS: Waypoint name (symbol label) in two rows [duplicate]

I have couple of longer waypoints names that I would like to put in two rows with center formatting but I just don't know how? I tried to put tag but it doesn't help... For example I have the ...
0
votes
1answer
75 views

how can I join excel sheet with point shape file?

How can I join an excel sheet with shapefile (Point) and common field is station code. In excel one station code has multiple rows and I want to attach those values with shapefile.
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0answers
86 views

Loading max WSEL from HECRAS in RiverGIS plugin?

When I Load max WSEL from HECRAS in RiverGIS plugin, I don't know What it happen? An error has occured while executing Python code: Traceback (most recent call last): File "C:/Users/duy/.qgis2/...
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0answers
120 views

QGIS 2.8.2 - Using spatial expressions in labelling

I'm creating some hard copy map output from QGIS. I want to use an expression to suppress labels for some features on a layer when another feature from another layer intersects with those features. ...
1
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0answers
59 views

Polygons in Polygons

I have 2 layers, they represent 2 different data. I did a spatial join to see the polygons that fall in the other layer using the match option as identical. Before, i used the intersect as the match ...
3
votes
0answers
93 views

SAGA hydrological analysis in QGIS 2.8 on Mac

I am running QGIS 2.8 on a Mac machine and I want to calculate the catchment area using SAGA - Catchment Area. It starts running but after a while when QGIS wants to open the generated files there is ...
2
votes
1answer
82 views

QGIS feature subsets are incompatible with table joins. Bug?

When using QGIS 2.8.2, I am unable join a table to a layer that has a feature subset (Layer Properties > General > Feature Subset). For example, creating a feature subset on a layer prior to joining ...
2
votes
2answers
276 views

QGIS/Python script to generate random points many times

Good day. Can anybody provide a simple code to be run in the Python Console of QGIS (I am using 1.8 Lisboa) to generate X number of random points (say e.g. 5000) over a certain global shape of ...
3
votes
0answers
105 views

Which projection can I use to see alignments on great circles?

I want to put on a QGIS map some historical sites to check if they are aligned. If an alignement exists, the points should stay on a great circle (is this correct?). I want to visually verify this ...
3
votes
2answers
111 views

How can I move the toolbar if its holder is out of screen?

While I was editing the toolbar, the holder stayed out of the screen. so I can't move it. How can I fix it?
4
votes
2answers
304 views

Map canvas overlay layers QGIS

I built my own map canvas inside a plugin in QGIS and I want to add two layers (one by one) in order to overlay the two. I have this code: fileCI = "....\plugins\teste\test.shp" fileInfo = QFileInfo(...
3
votes
1answer
130 views

Speed of people measured by gps

I was tracking tourist's movement patterns in a city with GPS and I would like to know the speed of all participants (60). The data were recorded and saved in gpx files, so in order to open it and ...
2
votes
2answers
408 views

Why is SAGA from the Processing Plugin not recognised?

Similar to this post: SAGA algorithms don't work in QGIS 2.8 except the fact that SAGA does not appear at all in the Processing Toolbox: As a check, I used the Python Console with the following ...
1
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0answers
79 views

How to avoid “Handle bad layers” message when opening a QGIS project file?

Most of the time I have to reload all the layers when opening a QGIS project file (.qgs), which is pretty annoying. I didn't change the name of the files and folders and I didn't change the folder ...
1
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0answers
28 views

migrate an application under 1.6 to 2.8

i would like to know what are the recoomandation if i want to update an application based on a old version of qgis in my case my application was written using the 1.6 qgis, and now we want to use it ...
2
votes
0answers
50 views

Generate ID for the grid of points from top-left corner down [duplicate]

I have a grid of points extracted from a raster. I need to give them a new ID value to be able to join values from it to another grid in rotated system of coordinates.The automatically generated ID ...
1
vote
1answer
182 views

How to remove vector grid cells that don't overlap with features from a certain layer in QGIS?

I am working on displaying a road network with QGIS (2.4). Doing this I have a couple of layers, including a base network of roads, and my modified layer. All in all they become a huge network. ...
2
votes
1answer
199 views

Compile pluging for qgis 2.8.2 with pb_tool or Makefile, in windows

I created my pluging with pluging builder, after compile the resources file, i test my pluging in Qgis. I modify the ui file in QtDesigner, but i don't know how to compile it in order to see the ...
1
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0answers
114 views

import qgis geoprocessing tools in python os x 10.9.5

I'd like to use the python bindings from qgis, but in a standalone project. I need the geoprocessing tools for vectors. I updated QGIS (Wien - 2.8), python (3.4.3), etc. However, it always ends with ...
2
votes
2answers
263 views

NDVI from Landsat8 LandsatLook images

I have downloaded landsat image from this site and now Im wondering if i can get NDVI index from it. In raster calculator I have only 3 ranges, shouldnt be four? Or am I doing something wrong......
2
votes
0answers
105 views

QGIS python originalName() does not return actual original layer name

I am writing a Python QGIS Plugin, using QGIS version 2.6 as the basis for development. When loading data into the canvas programmatically, I am trying to maintain the spatialite table name as the ...
3
votes
1answer
75 views

Error Packaging QGIS 2.9.0

I am attempting to package QGIS from source and the creatensis.pl script is exiting with the error: Running NSIS Can't open script "Master'" running nsis failed [makensis -V1 -DVERSION_NAME='...
1
vote
1answer
32 views

Get page coordinates of QgsComposerMap

How do I get the coordinates in page units (i.e. millimetres) for a QgsComposerMap item? I can get the upper left coordinate using pos, but can't see any method that provides access to the width and ...
0
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1answer
52 views

How do i match Layers in QGIS

am trying to create a map, which shall show NRW ( a part of Germany) with some extra gimmiks. Those Gimmiks are Coordinate based locations of several Manufacturers. Later on i want to adjust the ...
1
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0answers
150 views

How to display missing objects in QGIS 2.8.2 cartogram?

I've just created cartogram using styles/graduated symbol. But there are some missing elements on the map. Objects without data in attribute table are not present on the map (NULL in corresponding ...
1
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0answers
31 views

'Locking' intervals in interval determination

Working with graduated maps in Qgis 2.8 I'd like to lock a certain interval value while letting Qgis determine the rest - in relation to eg. missing values. I know how to work with queries, but this ...
2
votes
2answers
527 views

How to extend line features up to their intersection point in QGIS?

Is there a tool or plugin in QGIS to extend line features up to their intersection point?
1
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0answers
127 views

extract x-y from a point created from lat/lon coordinate

Using QGIS 2.8.1, how can you create a point in WGS 84 using a lat/lon and extract X and Y value of this same point in CRS UTM34N. For eg, you have been given a lat 20 deg and lon 50 deg. Create a ...
1
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1answer
518 views

How to set CRS in QGIS using pyQGIS

This question is very similar to these one , but it's doesn't work for me. This is my try: ........ vlayer.setCrs(QgsCoordinateReferenceSystem(25830)) iface.mapCanvas().mapRenderer()....