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

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1answer
44 views

Why doesn't Dissolve with stats plugin work in QGIS 2.14?

In ArgGIS 9.3 there is a function of ArcToolBox named Summary Statistics (Analysis). I'm finding a similar function on QGis. One of these is Dissolve with stats (plug in) but on my version of QGIS (...
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34 views

Is ST_Geom included in AWS RDS postgres 9.5?

I have a database instance on AWS RDS using postgreSQL 9.5. I am using ArcGIS desktop 10.4 and connecting to this database. The Arc docs mention needing to place the ST_Geometry.dll in the postgres ...
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29 views

QGIS options menu causes freeze on Ubuntu 16.04, solutions?

First time asking, I've checked the internet and no luck. I am unable to edit the program options in QGIS 2.14.3 running on Ubuntu 16.04 (settings -> options). I've uninstalled all QGIS packages (...
4
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1answer
74 views

How can I specify a Minimum and Maximum Word Wrap length in QGIS?

I want my labels to fit nicely within polygons. Based on this answer I discovered the power of the wordwrap function in QGIS to make labels. However, I'm confused as to how I could specify a minimum ...
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1answer
33 views

pgrouting to calculate distance using a chosen highway system

I am working on a research to calculate the distance of firms (scattering around the nation) to several metropolises via selected national highway system. Then I overlay the highway map with firms' ...
3
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1answer
32 views

How to convert multipoint layer to polyline layer in QGis

How can I convert a multipoint layer to polylines layer in QGis. I am looking for a tool equal as the GeoWizards (convert > Multipoint to polyline) for ArcGis.
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0answers
13 views

How do you test QgsDataSourceURI.setConnection is valid in a QGIS plugin?

I am currently trying to write my first Python plugin for QGIS and I'm using the the uri = QgsDataSourceURI() uri.setConnection(host,port,db,username,password) syntax to create a connection to an ...
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1answer
22 views

How do I control the behavior of the QMessageBox

I'm working on my first plug-in. In an attempt to validate the user selections on the dialog, I am using a message box to return messages to the user if an error is found. The messgae box displays ...
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1answer
20 views

How to reimport/copy a shapefile where attribute table can be subsequently edited without changing original shapefile in QGIS

QGIS 2.8.9 I am having trouble when duplicating a shapefile and then going on to edit the attribute table of the duplicate manually. The changes I make are reflected in the original file - hence ...
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20 views

QGIS 2.14 v.what.rast missing

I'm using QGIS 2.14 on Ubuntu 15.10 and missing the function v.what.rat(https://grass.osgeo.org/grass70/manuals/v.what.rast.html). I also installed QGIS 2.14 on Windows where this function is also ...
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43 views

Why do merged rasters in QGIS look 'patchy'?

Poor title for this question, but I can't think of a better way to explain it. I have merged two rasters. I want the joins to be seamless, but there is an obvious line where they meet... I've ...
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0answers
10 views

How do I create an inverse-distance weighted attribute mean map?

An attribute-weighted heatmap applies inverse distance weighting to each point in a set proximity and adds them all up. I am searching for a tool in QGIS or another software that allows me to do the ...
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0answers
19 views

Re-import custom functions without restarting QGIS

I have a python file (in [user]\.qgis2\python) with some functions that I'm working on. It's just a .py file with a bunch of def function_1, def function_2 etc. in it. On startup I import the .py file ...
1
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1answer
44 views

import Map from QGIS into QT Designer

I am looking for a way to get a map from QGIS into QT Designer. I have the QT Designer version that comes with QGIS, meaning i have all the standard QGIS Widget. I don´t see a map widget, but many ...
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1answer
28 views

Why don't all columns appear when changing style of shape file for cartography in QGIS?

QGIS 2.8.9 I have been working with this shape file and have already successfully coloured it using a graduated style from my column 'TIV' - however recently when I want to change the attribute the ...
2
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1answer
33 views

Clipping layer when using new projection in QGIS?

I'm having trouble clipping a shapefile in QGIS so I'll take you through my steps. I've downloaded the land shapefile here http://www.naturalearthdata.com/downloads/10m-physical-vectors/ When I load ...
2
votes
1answer
29 views

Separating a shapefile with specific features into a new shapefile using PyQGIS

I have a shape file. I would like to know if it is possible to classify the different layers in that shapefile (like highways, local roads, rail lines, etc.) with MTFCC and extract a separate ...
4
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1answer
47 views

How to create random points in overlapping polygons?

I have a shapefile with ~1840 polygons, many of which overlap. I'm trying to find a way to create 1000 random points per polygon, based on polygon ID. I don't see a way to this using the GUI Random ...
3
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1answer
40 views

QGIS problem exporting to both SVG and PDF

I'm having a problem when exporting to SVG and PDF from qGIS. When I open the SVG or PDF in Illustrator, the path of my map is severely cut off with lots of data missing (see below). When I open the ...
4
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1answer
48 views

New features to shapefile in QGIS end up with previous features attribute values - why?

When I digitize a new feature to a polygon shapefile in QGIS the attribute data of the new polygon is replaced by the data entered into the last feature created. Has anyone else ran into this issue? ...
2
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1answer
37 views

QGIS Field Pyculator Reclass

I'm new to the QGIS Pyculator and need to reclass a field ('AP') based on another field ('Mag'). What I have so far, from the ArcGIS field calculator: def Reclass(Mag,AP): if Mag>= 2000: ...
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0answers
12 views

GRASS v.net.iso does not include all lines

I want to define catchment area for bus stops in small city. As a result of v.net.iso in QGIS with GRASS I don't get all highways in that city. Here are my steps: importing above layers into GRASS ...
3
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0answers
45 views

How to use the 'Check Geometries' plugin for polygons?

I've a few hundred polygon features with many duplicate nodes, gaps, overlaps and other geometry errors. Fixing all errors seems to be quite tricky. I had to run the duplicate nodes check twice to fix ...
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1answer
42 views

Numbering adjacent polygons in sequential order

In QGIS is there a way to assign ascending numbers (attribute) to polygons that are located in a row. The polygons were not created in sequential order.
2
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2answers
63 views

Save line geometry as points geometry in QGIS (pyqgis)

I have line and polygon layers. I want to make a list of points' coordinates (ends or begginings of lines), which are touching the polygons. The coordinates which I need are selected as yellow. ...
3
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1answer
65 views

OSM data appear in very low quality in QGIS

this is my first map creation attempt in QGIS 2.8.2. I am having troubles in making it look good though with OSM street map data in particular. I import data via the Web>Open Layers Plugin>...
3
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2answers
51 views

How to split string (the last digits) in QGIS?

I´m working with QGIS 2.12. Is it posible to split string "from the right side" (it means I needed the last text from every field)? In one field I have description like: new street 25 old street 2 ...
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3answers
85 views

Convert raster to a CSV values and lat long based on raster value in QGIS

I am looking to convert a raster into a csv file (or tab delimited) based on values in the raster (Value > 0). The csv would have three values, latitude of center of cell, longitude of center of cell,...
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0answers
36 views

Creating random points using density-QGIS

I'm trying to generate random points at a specific density within a polygon layer. The polygon layer has 1850 features and I'm looking to have random points within each feature at 1/meter. Going ...
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0answers
15 views

QGIS Point Features and Labels Not Appearing in .KMZ/Garmin

I want to produce a Garmin custom map for use with my Etrex 20x. I'm working with QGIS 2.14.3-Essen using the GarminCustomMap, version 1.1, plug-in to produce the output .KMZ on a Mac running OS X ...
2
votes
2answers
31 views

QGIS clipper tool misaliagnment

I'm using QGIS 2.14 and GDAL 1.11.3 and I'm running into a weird error with the clipped outputs. I created a shapefile in QGIS and used it to clip my image. Here's a simplified version of the ...
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0answers
17 views

decimals and commas in QGIS - how to display in Qt designer form

I use Qt designer, create a new form, add several line edit (qLineEdit) widgets, rename them the same as the fields in a QGIS attribute table, and save. In QGIS I associate the new .ui file in Layer ...
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2answers
70 views

How to Continue a Line Feature in QGIS?

I'm looking for a way to continue a line feature in QGIS. I have checked the Digitizing Tools plugin (both regular and advanced) for a Prolong Line tool, but I haven't had luck. In ArcGIS there's a ...
1
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1answer
22 views

How to load specific PostGIS features from a given table into QGIS?

I have a table in my database built like this: contour_id / (INT) project_id / (INT) contour_lvl / (INT) contour_geom (MultiLineString Geom) Each row in this table is a contour feature associated ...
2
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0answers
28 views

Error editing 'editable' view in QGIS

Taking some code from this post, I've been trying to create an 'editable' view in PostGIS. I'd like to store label placement properties in a separate table, build a view of the data I want to use for ...
1
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1answer
30 views

QGIS: Automatic shapefile input for pre-constructed automated workflows

I currently have two models running: Take shapefiles and break them down into separate shapefiles based on their class, and save them in a specific folder; Select the broken-down shapefiles with the ...
2
votes
1answer
46 views

Cluster analysis using buffers and polygon features (NOT layer)

I have a point-based vector layer, where each point represents a road accident. I am trying to write a function that: Loops through my accident layer creates a buffer, of a given radius, around each ...
4
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1answer
44 views

Representation of Summary statistics in QGIS composer

Is it possible to display a summary of statistics from a certain attribute within a feature class within the print composer using an sql statement. I have an shapefile "projects" with a number of ...
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0answers
37 views

QGIS freezes using MMQGIS plugin

I have a problem with geocoding addresses (about one thousand). I have a file (.csv) with a large number of addresses: street, house number, ZIP code, city. I used the mmqgis plug, but after geocoding ...
1
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1answer
41 views

How to simplify a land cover classification in QGIS

I have recently completed a land use classification using over 100 ROIs for 5 different land cover classes and it has developed what looks like a highly specific spectral signature for each class. ...
3
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0answers
30 views

How to access qgis module from my virtualenv

I am running an Ubuntu 14.4 and I have installed a python virtual environment. Then I pip installed several python libraries (gdal, lxml, psycopg2 etc.) Also in my system I have the module for qgis. ...
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1answer
41 views

Load a specific spatial data from a postGIS table

A single postGIS table contains multiple type of spatial data(example: Linestring,Polygon,etc.,). How to load a specific spatial data from PostGIS table into QGIS by using pyqgis?
8
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1answer
112 views

How do I Spatially Partition a whole lot of points?

I have location data of customers, with over 130 million records, spread all across the country. This is a Spatial Table in PostGIS I want to now partition the entire country into 'service areas', ...
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0answers
39 views

Local variable 'value' referenced before assignment: qgis function editor

I customized a function to edit my attribute table. It was working well but now when I used it again my qgis crash or I receive bad answer. The answer of Qgis: My code: from qgis.core import * @...
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0answers
18 views

S-52 symbology in QGIS

I can load S-57 ENC vector files in .000 format and view the data. I would like to visualise them as the S-52 standard details. These are nautical charts, some more detail here: https://en.wikipedia....
2
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1answer
52 views

Defining Datum in QGIS?

I got two shapefile of the same coordinate reference system (CGRS93_LTM), one in QGIS and the other in ArcMap. However they got different prj. files QGIS file: PROJCS["Transverse_Mercator", GEOGCS["...
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0answers
44 views

Linux based QGIS File Geodatabase access

I have looked for a "recipe" to get QGIS to read FGDB but cannot find anything. I'm fairly new to Linux and need a step by step procedure or somewhere to find the steps. I'm running QGIS 2.14.3 Essen ...
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2answers
54 views

Get the coordinates of all points having the same given latitude along a line shapefile

I have a shapefile representing a shoreline and I need to extract the coordinates of the points at a certain latitude (or longitude). Is there a tool or plugin that could do that ? Edit: to be ...
0
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1answer
30 views

Quick way to produce polygons to cover variable precision lat / lon points?

I'm using the Smithsonian Global Volcanism Database and have a .csv lat lon points from it. It seems they are using decimal precision on their lat lon to give a rough idea of the size of the area that ...
1
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1answer
37 views

How to update a text column of selected features in QGIS?

Let's say I have a bunch of postcodes. After making a selection and having the records highlighted in the attribute table, how to update all of them and give them the same category? In ArcGIS, after ...