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

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5 views

finding closest -longest line in qgis

how can i find closest line of polygon to the point within it in Qgis?.i have used mmqgis plugin for this but hub layer and polygon layer plcement are not matching though both are having same CRS
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0answers
8 views

How to indicate flow of a watershed feature?

While tracing and digitizing rivers, streams, rivulets, etc., is it possible to indicate the direction/flow in the shapefile on QGIS? I'd like to avoid using map labels. Ideally, when done tracing, I ...
2
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0answers
9 views

No more error messages after importing QGIS modules into python

I have a problem when writing python code whilst including the qgis modules. As can be seen below, when I usually call a variable that does not exist (for example), I receive the usual error message. ...
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1answer
8 views

Why can't I open a kml layer?

I thought that I could open kml layer like a normal vector layer but it doesn't work (it says "invalid datasource"). How can I open a kml layer in QGIS? Or how can I open it anyway, I never worked ith ...
1
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0answers
11 views

Taxi fleet simulation - MATSim a useful tool?

I am working on a university project and I would really appreciate some advice: My project consists in modeling the taxi fleet of a major city and investigating if replacing a percentage of the fleet ...
1
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1answer
10 views

reproject vector layer with pyqgis with new CRS does not worl

In QGIS I am running a script in th python toolbar to export all visible vector layers to a GEOJSON with this snippet: canvas = qgis.utils.iface.mapCanvas() allLayers = canvas.layers() for i in ...
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1answer
38 views

OpenStreetMap not crystal clear in QGis

OpenStreetmap (OSM) doesn't give us crystal clear views on screen and on prints. Some time ago that was good.. We don't know if we can adjust that. We've tried QGis 1.8 and 2.2, no difference.. OSM ...
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1answer
21 views

Opening QGis-project via windows explorer

We have upgraded from QGis 1.8 to QGis 2.2. Qgis 2.2 is first installed, then 1.8 removed. Since then it is impossible to open .qgs-projects directly from windows explorer. We have checked explorer, ...
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1answer
18 views

QGIS hides few graduated points after reopening project

I have a strange problem in QGIS 2.2 (problem is also present in QGIS 2.1). When I add a point (shapefile) layer, apply graduated style and change point size, everything looks fine. Then I save ...
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1answer
11 views

QgsFeatureList features as QStrings

I am catching the selectionChanged signal and passing the selected layer to the registered method. Once here, I want to know the features that were selected. I do this with a call to ...
4
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0answers
53 views

How to do Manhattan Voronoi on QGIS?

I've spending last two weeks trying to discover how to do a Manhattan Voronoi on QGIS. For the difference between Manhattan Voronoi and "normal" Euclidean Voronoi, please check this link Can someone ...
2
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3answers
20 views

QGIS Mosaicing with null values in images

I have a set of landuse landcover data which needs to be mosaiced. Whenever i try using QGIS Raster>miscellenous>merge tool. giving no datavalue as '0', it returns either (A) ' Traceback (most ...
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0answers
22 views

C++ and Quantum GIS

I wish to develop/customize with a combination of C++ and Q GIS (Windows OS). I downloaded QGIS but couldn't find header (.h) and library (.lib) files. Where can I find them?
1
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0answers
19 views

Programmatically modify layer datasource on project save event (QGIS)

I have a QGIS plugin which allows users to add WFS/WMS layers to the map. I would like to be able to scramble the user ID part (token) of the uri when the project is saved/closed and then use my own ...
1
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2answers
81 views

How does one export the list of stored WMS-servers in QGis?

Could anyone point me as to where QGis stores the list of WMS-servers you added? I have built a fairly large list of WMS-server on one computer, but the QGis-project file which gets accessed by my ...
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0answers
30 views

QGIS custom form and autocompleted data entering with “validation check”

In Qt-Designer I created a custom form where I can choose serveral species names in two different combo boxes. This combo boxes are linked via "value relation" to the accordant non spatial tables ...
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0answers
27 views

length and width of polygon

how can i find polygon's length and width in Qgis(regular polygon and irregular polygon)? i have area and perimeter but possible to have length and width ?.
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0answers
9 views

argument 1 has unexpected type error when parse xml with ElementTree

I try to make plugin in QGIS Dufour to open and read xml metadata and then to show some information in metadata i try to parse it with ElementTree and then show it in QLineEdit, this code i use to ...
6
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3answers
157 views

Merge images first, or georeference first?

I'm wanting to georeference and vectorise some features from scans of the OS 1896 Town Plans that I have purchased from the NLS (http://maps.nls.uk/os/london-1890s/info.html). The scans provided are ...
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0answers
18 views

Help Qgis cloud [on hold]

I need help for one problem. I want to publish my map, but they are one error for load data, i have my firewall shutdown, the shp don't have spaces and -., but the error persist. You can help me? One ...
0
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0answers
18 views

QGIS-QT designer. How to create a form that allows editing elements linked by one to many relationship

I know this question has been already asked on this forum, but I really have not found any answer, not here, not anywhere. My question is simple, I have a Spatialite DB having one spatial layer (Pole) ...
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2answers
36 views

Where are QGIS application setting file(s) stored?

I have some application settings (Windows/QGIS v2.0) that I would like to pass to other users (such as those settings defined under Settings menu>Options>Rendering tab). In ArcGIS they are stored in ...
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0answers
24 views

Is there a decent algorithm in QGIS Process Modeller to create a grid?

I am using Process Modeller to automate merging several vector layers and then creating a grid to cover the extent of the merged layer. There are functions which already exist which are not listed in ...
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0answers
12 views

QGIS: graphical-modeler to calculate area of polygons

I'm trying to calculate the area of polygons using the field-calculator in QGIS (2.0.1). If I do this manualy it works fine, but if I do this using the graphical-modeler I get NULL as area for every ...
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0answers
32 views

How can I see the overlay of two features (point & polygon)?

I am trying to open two digitized layers, one containing points in a region and second which I have downloaded separately for the region as polygon layer. I would like to overlay two of these layers ...
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0answers
9 views

Why there is no output (path) for Dijkstra in pgrouting

I have a road network table and I am implementing pgRouting. everything was working fine previously but now there is something odd here. I am getting no route now. I am checking through sql query in ...
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0answers
16 views

not able to use R 3.0 in qgis 2.0 desktop version

I have installed Qgis 2.0 desktop and R 3.0 . when i want to access R scripts in Qgis gui, not able to work why. may i know whether it is correctly installed or not. i have given R folder path ...
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1answer
28 views

How to use QGIS field calculator to delete style code?

I am struggling with following issue: How to delete style code before id codes x.x.xx.. and the }s in the end? Examples below. Any help appreciated! {\fArial|b1|i0|c0|p34;A.B.11} ...
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2answers
39 views

How to make multiple qgis mapbook pages in 1 pdf?

Is it possible to export a mapbook in QGIS 2 with multiple pages all in one PDF? Thanks
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0answers
30 views

How to add Georeferenced PDF as layer to QGIS 2.0?

I have some georeferenced pdf's that I would like to open in Qgis. I have read that GDAL version 1.8 and higher will support pdf, and I have GDAL 1.10 installed with Qgis 2.0 on windows 7, But when I ...
1
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1answer
38 views

Spatialite Table Difference in QGIS

I am see differences between tables when I view them in spatialite-gui and in QGIS. I have created a table, added columns, and updated the columns in spatialite-gui. Within spatialite-gui I can view ...
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0answers
18 views

Error: .asc is not a supported raster data source

I am new using QGIS and struggling with this error "...... .asc is not a supported raster data source" when trying to add a ."asc" file as a raster. I downloaded the files from ...
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0answers
26 views

QGIS locks up when loading shapefiles [on hold]

I have QGIS loaded onto a handful of computers within an organization. One of the computers is giving me a headache. When I try and load any shapefile from a network share, QGIS 2.2 or 2.0 freezes. ...
0
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1answer
29 views

Mac QGIS files to Windows Arc GIS compatibility

If I download QGIS on to Mac will the shapefiles and layers I create be compatible with ESRI ArcGIS 10.1 on windows?
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0answers
15 views

Error 14: Could not open CRS database

I am using Python Console and loading a Vector Layer using python commands. When the layer is added, QGIS first asks for the CRS to use, but I don't have all the CRS listed out to select the Reference ...
1
vote
1answer
46 views

extract shapefile attributes from raster colors

I have two layers: a shapefile with states and counties (shp) a raster file (with colors and some text and borders, but not a perfect map) (tiff) I want to use the colors in the raster file to ...
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0answers
51 views

List of GIS software that runs on a server [on hold]

OK, I searched to see if this had been asked, but couldn't find it. I'm looking for a list of GIS software that will meet my needs listed below. Runs on a web server (this is where the other lists ...
0
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0answers
21 views

HTML Annotations

I am trying to insert html annotations into my map. I was hoping they would be interactive and pop up as you move over or click on a feature, but they don't seem to function this way (that I can ...
1
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2answers
54 views

QGIS Select by Expression

A basic QGIS 2.2.0-Valmiera, Select By Expression - Field Calculator question. Introduction I am a geologist searching through a geological database (see attached figure). I have a shape file and ...
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0answers
24 views

How to add button in google maps where i have polygon? [on hold]

we are plotting polygon on google map using script.I want to add one button where my polygon plots. Using Front end as .net we are plotting polygons in google map.We need to add one clcked button on ...
3
votes
2answers
140 views

Unable to get python-qgis-common on Kubuntu 14.04

just upgraded my Kubuntu from 13.10 to 14.04 LTS and lost all plugins. Found out that "python-qgis-common" is not installed. Tried to install it but was told that it depends on "sip-api-10.1" which ...
1
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1answer
27 views

Split a line feature using nearby points

I have a line shapefile and a point shapefile, and the line has its own segments and its attribute table, the point shapefile has points near the line above, not on it and the close ...
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0answers
15 views

QGIS 2.2 Changeing txt data in theme table not working

A week ago I upgrade from QGIS 2.0.1 to 2.2 and try to edit some simple point themes I made recently. To my surprise, QGIS 2.2 randomly - not allways, does not allow me to change text I type into text ...
1
vote
1answer
160 views

QGIS crash Ubuntu 14.04

Encountering a crash when requesting QGIS 2.2 to access data on desktop machine. Running Ubuntu 14.04 LTS. $ qgis Warning: loading of qt translation failed [/usr/share/qt4/translations/qt_en_AU] ...
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0answers
12 views

Split/Erase/Differentiate polygon by polygon within a same layer

Is it possible to split a polygon with a polygon within the same layer in QGIS ? As in the image, i want the Polygon 2 to be split & the pointed area has to be retained as a separate polygon. ...
0
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1answer
17 views

Building with MinGW 4.8

I'm working on a project where we would like to add QGIS features to an existing Qt application. The Qt application has been built with Qt5.2.1 using MinGW 4.8 and thus I think I need to build QGIS ...
0
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1answer
37 views

QGIS 2.2: GDAL Grid (Interpolation) Error

As much as i understand Raster -> Analysis -> Raster (Interpolation) can provide me with a terrain file out of a shape file with a Z coordinate. I select the input and output file and a Z field. It ...
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0answers
32 views

back up of qgis file

Can we recover a previously saved version of qgis file? For example: I have saved my qgis file about an hour but I need the yesterday's back up of qgis file. The file which does contain today's saved ...
0
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3answers
41 views

How do I use QGIS 2.2 to plot some locations on a map (of the US by zip code)?

I am a newbie to QGIS. I just installed it on my MAC Airbook with Mavericks. How do I simply plot a few locations on a map of the US? All of the tutorials I can find on the web are for older ...
0
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1answer
42 views

Excel Nad83 table to gpx-Total noob

I have some waypoint locations that I have entered into a spread sheet in Nad83 the format of table looks like this NAME, -, -, UTM ZONE, Easting, Northing, -, Comment 1184236, 1, CP, 15, 451596, ...