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

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QGIS Processing Plugin Not Loading

I am having serious issues with my QGIS program regarding the Processing Plugin. Upon start-up and if I turn on the plugin within the program. I have uninstalled and reinstalled the program. Have ...
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0answers
8 views

Handling features as events

I have a question related to handling features dynamically. In the two desktop GIS systems QGIS and ArcGIS we can import CSV files or database tables as XY events. These can be handled as dynamic ...
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0answers
9 views

QGIS Generating a Lat/Long Degree Grid in Composer

I made a map in WGS84, which is positioned and referenced correctly. Now I loaded the map into the Composer and added a grid, with horizontal and vertical lines each 500 world units (m). When I ...
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0answers
18 views

How can I average point features spatially in QGIS?

I have a GPX file with track points and I want to average the points spatially to improve accuracy of the point feature. I can't just make a polygon and find its centroid as the number of overlapping ...
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1answer
10 views

How to create a specific svg file with data from a feature

I am working in c++/ QT4.8.5, with qgis api c++ 2.8.2 I have to display a dynamic icon for a feature. some of the data change periodically and in order to display the change i need a svg that can get ...
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1answer
19 views

QgsExpression using complex sql and python subsitution

I have a sql statement i am running in postgres fine and would like to transfer it to a QgsExpression mainly because I have loaded the layer in Qgis. My sql is: select column a,column b from table1 ...
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0answers
10 views

Tracing a raster layer in QGIS [duplicate]

I have a basic map I would like to trace into vector form in QGIS. The map is just a JPEG and has no coordinate reference data. Whenever I import it into QGIS, it ends up as a tiny speck at 0,0. How ...
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14 views

Qgis 2.10 unable to add a new feature in spatialite via sql function “GeomFromText”

Using Python code in my plugin the function in sql language "GeomFromText(POINT(X Y))" gives the following error: "OperationalError: no such function: GeomFromText" Plugin functions in previous ...
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2answers
28 views

Syntax error in parameter formula of field calculator funtion

I'm using a QGIS 2.8.1 in windows. Have some doubts with syntax when use string in python console. I want to use the field calculator funtion like: processing.runalg('qgis:fieldcalculator', input, ...
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1answer
27 views

messed up shapefile attribute table text

I have a .shp file from AutoCad imported to QGIS (using _MAPEXPORT > text in AutoCad) and this is what happens to text in attribute table - example: {\Fsimplex|c0;O\Fsimplex|c238;Š\Fsimplex|c0; ...
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0answers
16 views

Interpolate precipitation Data on fly and save result in text [on hold]

How to spatially interpolate on fly large daily(365 days) rainfall data and save the resultant precipitation of particular desired point(lat, lon)
4
votes
1answer
35 views

Exporting Contours from QGIS into AutoCAD [duplicate]

I'm trying to export contour lines from QGIS into standard AutoCAD but I'm not having much luck. It does not seem to matter what type of file I select as the output during the contour creating (eg. ...
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1answer
26 views

How to reduce points by proximity

I got a layer with over 4 million points. The distance between the points are 1 meter. How can i reduce the data so that no points have less than e.g. 10 meters between them?
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0answers
27 views

Polygons within Polygons Spatial Analysis

I have a polygon layer of planning applications and I am wondering if anyone can give any advice and or has seen or written a blog post that might point me in the direction of creating relationships ...
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0answers
25 views

About performance of qgis with big layer or a lot of layer

does anyone has a feedback on the performance of a big layer by exemple : I have a layer with 100 features, each feature contains specifics attributes with dynamic data, the data change each second ...
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0answers
11 views

GeoExplorer not display the associated table to a layer

GeoExplorer shows the table information associated with a layer of 2 ways: Information button: clicking on the map is displayed a tab corresponding to the polygon attributes where you click. Query ...
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1answer
17 views

SVG To Shapefile [duplicate]

Is it possible to draw out some SVG shapes in Illustrator or Inkscape and convert them to Shapefile using GDAL or QGIS (or something else perhaps?). I have an image that I can easily georeference, ...
1
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1answer
21 views

Calculating field on insert (real time) using QGIS?

We use QGIS as a field application. We like to calculate with a input value and then also calculate with the result of the calculation Example: Liters: 1000 -> Liter per container: "this has to be ...
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0answers
20 views

How to add coordinates to an image in QGIS? [duplicate]

I use QGIS 2.10. I have a map image without any coordinate or boundary info. I need to convert it to kml file and before this, I need to add specific coordinate info for this map. How can I add ...
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0answers
19 views

How to visualize updating lines of bearing from a point

I'm working on a project where I need to visualize a constantly updating line of bearing from a point, based on degree of rotation around that point. My plan is to design a line feature with an ...
2
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0answers
18 views

How can I use a DBF layer in an R script in QGIS?

How can I use a DBF layer in an R script in QGIS? For example, I can input a vector by using ##Layer=vector, and a CSV table with ##Table=table, but it will fail if the table is based on a DBF file. ...
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1answer
27 views

Paths with least elevation gain

I have a DEM of a city with numerous hills and a shapefile of the city streets. I want to find the five paths from a low point A to a high point B on the street network that involve the least ...
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18 views

32Bit QGIS 2.10 Problems with Gdal WMS TMS google maps layer

I have been using gdal wms layers to view various basemaps in QGIS. I am using this technique rather than open layers because this I can reproject gdal WMS layers as needed. When I get close to the ...
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1answer
37 views

How can i calculate the distance to the nearest five neighbors for a polygon layer?

Data set (shape file) contains polygons. How can I calculate the distance to the nearest 5 polygons in the data set in QGIS?
2
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3answers
54 views

How to host QGIS threejs outputs?

Is there a free simple way to serve / host the .html files the awesome Qgis2threejs plug-in produces? I have tried using Google Drive as shown here and here without success. Also had same results ...
2
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0answers
18 views

How to show only some layers in the QGIS legend

I hope this is still kind of a QGIS related question. My QGIS 2.8.2 standalone app provides several decorating layers (e.g. cartographic grid, background layers, reference points) which should be not ...
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0answers
11 views

Zonal statistics shifted

I am working with QGIS (newbie). I have a raster map with 0.5degrees resolution. I created a 0.5degrees width grid layer and I compute zonal statistics from the raster. My problem is that it seems to ...
2
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1answer
49 views

Why I see a gap between ESRI Robinson WGS84 (EPSG 54030) VS QGIS Robinson WGS84 (EPSG 54030)?

Does anybody know why there a gap appearing between two point layers create with ESRI and QGIS when I a reproject, from the same source file, to Robinson ? The source coordinate system and ...
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0answers
35 views

Deciding variables for image classification?

The results of an image classification may vary A LOT depending on the variables you use from the beginning. Number of classes, minimum class size, sample interval, atmospheric corrections, ...
1
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2answers
36 views

is it possible programmatically to rotate a svg of the feature without rotate all feature

I am working on a project that need to move and update the shape of the feature of the layer. I am working in c++/ QT4.8.5 and qgis api c++ 2.8.2. In my Layer I have a lot of features, each feature ...
2
votes
1answer
26 views

Recast data from one geographic standard to another

I'm working right now a project looking at medical labour supply in rural areas in Australia. I aim to use STATA for most of this analysis, but a change in geographic standards by the Australian ...
2
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0answers
19 views

QGIS Set Composer Legend to shrink the font size to fit

QGIS 2.10.1. I have read that it is "impossible to make the legend smaller then its contents". Is there a way to set the legend to shrink the font size when re-sizing the bounding box? Or when you ...
3
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1answer
65 views

What projection to use to get a game map into QGIS?

I have built and maintain a SWTOR game map atlas. At the moment, it's all static jpg maps, but I would like to get the info into an actual GIS software to get more functionality and make my website ...
3
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0answers
20 views

How to randomly select three points in each polygon?

I have two layers: first layer includes polygons of districts, second layer containts points (phytocoenological relevées). The goal is to create a new layer that will contain max 3 randomly selected ...
2
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0answers
23 views

qgis 2.8.2 always produces minidump on exit

QGIS 2.8.2 on windows 8.1 produces the below error every time it is closed. Anyone have any ideas as to why or possible fixes ?
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0answers
16 views

Text box with automated coordinate reference system in use on Qgis

Using an expression, is it possible to automatically fill a text box placed on the map (in the composer) showing the reference coordinate system of the project? If possible, how would that expression ...
0
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1answer
23 views

Creating an intersecting linestring layer from two polygon layers using some tolerance

I have two postgis layers: The first layer contains the sidewalks of my town (polygons in blue). The second one contains the pavements (roads) of my town (polygons in brown). The map looks like ...
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1answer
41 views

How to find the intersection length between two polygons using python

I have two polygons and i want to find the intersection line length between these polygons. for geom1,geom2 in itertools.permutations(selection,r=2): intersection ...
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0answers
22 views

qgis python: select on screen and change (pre-set) properties accordingly

I have a map with different zones where I have drawn isochrones -where I will arrive within 15 min, within 30 min and so on. The picture attached shows the 15-120 min isochrones. This is set as a ...
3
votes
2answers
83 views

How to create a consecutive alphanumeric column in a QGIS attribute table?

I am trying to create a column in the attribute table such that each cell lable is a prefix (M) follwed by a unique number ie M1, M2,.. etc
3
votes
2answers
124 views

Way to find minimum value from a group of values - QGIS?

I'm wondering if there is a way to find the minimum value of a group within QGIS? Basically I need to find the minimum distance of each unique value in a table of about 5000 records. I can do the ...
1
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0answers
27 views

QgsVectorLayer from delimitedtext fails

I am having trouble loading csv files into layers using QgsVectorLayer(). I know this looks like a repeat, but I have carefully read Create a script to add delimited text layer in QGIS and ...
2
votes
1answer
48 views

How to create flow maps in Qgis

I have several records from a survey and would like to show flow map from places mentioned in the survey. I have all places mentioned georeferenced and some records mentioned no places and others ...
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0answers
14 views

QGIS to Leaflet Projection Weirdness

I've been using the mmqgis tool to create a hex grid. It loads up in QGIS looking good, but when I save it as geojson and load it up in leaflet it gets stretched (see attached). It starts life as ...
2
votes
1answer
49 views

QGIS LTR vs other release

Just after some advice with respect to the QGIS LTR schedule. Our IT managers have recently intervened in our use of QGIS (a State Government Authority) and are wanting to put in place a policy to ...
1
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0answers
16 views

Adding to signature list from ROI list does not work?

I'm trying out QGIS with SCP, but I've run into some problems First of all, my setup is as follows: QGIS version 2.10.1-Pisa on Mac OSX Yosemite 10.10.5 compiled and running against qt 4.8.6 ...
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0answers
24 views

How to use interacting PostgreSQL/PostGIS triggers in QGIS?

I use point geometries (table 'label_point') to place multiple labels on polygon geometries (table 'soil'). After doing layer edits I've to update the affected label_point features. Therefore I've ...
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1answer
38 views

change SRID of shapefile and QGIS

It is possible to change the SRID from a shapefile to another SRID in QGIS ? I have a shapefile in 2100 srid and i want to change it in 4326 SRID.
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0answers
22 views

QGIS 2.8 printcomposer show image dynanic

I have a table with photo's, i now want to make dynamic map with discription en showthe photo. In the composer with atlas, so i can produce about 1000 pdf files Is this possible? The photo's are ...
3
votes
1answer
25 views

Problem exporting registers with the land registry in DXF continuation (suite) in reprojection

I visualize (display) a municipality with the plugin register with the land registry in spatiality and in projection Lambert 93. I need the bottom on Autocad in projection CC47 thus I re-throw ...