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

learn more… | top users | synonyms (1)

0
votes
0answers
46 views

How to cluster points based on both proximity to each other and proximity to another layer (roads)?

Using QGIS I have managed to created cluster for points based on their proximity of each other (using buffer and spatial joins etc), but I would also like to add another variable to it: proximity to a ...
0
votes
0answers
57 views

Split Lines with Points Layer Tool

I asked a question a while ago to figure out how to split a line layer with a points layer using QGIS, but cannot, however, get the accepted answer to work due to limitations of my knowledge and the ...
0
votes
0answers
13 views

Rotating points at intersections toward branching vector

I've successfully rotated points on based on the azimuth of a line, following the lead of this post. However, I now have reached an obstacle for one of my layers that occurs only at line ...
0
votes
2answers
46 views

Can't get dataProvider object outside of QGIS python Interpreter

Within PyCharm import qgis.core as qgis vector_lyr = qgis.QgsVectorLayer("Point", "distance nodes", "memory") pr = vector_lyr.dataProvider() print pr prints None Within Python Interpreter in QGIS ...
1
vote
2answers
81 views

How to compute percent of a field

I have a layer with a column conaining population values. I want to write an expression to compute in a new field the percentage of population each polygon has in relation to the total population. I ...
0
votes
1answer
61 views

Coordinate grid not showing in Composer

I went through every answer that I found here, but am either missing something in them or the question has not been asked. I have a very simple map consisting of four layers, namely contour lines, ...
4
votes
2answers
89 views

Storing SRID:4326 data as Geometry or Geography?

I used OGR2OGR to import SRID 4326 point data into MSSQL Server. Didn't realize that it defaults to creating a geometry column instead of detecting the data as 4326 and creating a geography column. ...
1
vote
2answers
60 views

How to get a set of all buildings of an OpenStreetMap section in form of single points / Multiple polygons as one point

The objective is to get a set of all buildings of an Open Street Map section in form of single points in a shapfile. I downloaded the section from osm. Imported the section into QGIS (and later ...
1
vote
0answers
84 views

Open PostGIS layer with QGIS 2.2

I just upgraded QGIS from 1.8 to 2.2 and I am getting some troubles to open a PostGIS Layer. The connection with the server works fine, I can see all my tables, select the one I want to open and even ...
1
vote
2answers
94 views

How to align/georeference distorted vector layers in QGIS?

I've got a shapefile which has been digitized from a strongly distorted historical map, and would like to align it as nicely as possible to another precise shapefile layer. The transformation must ...
0
votes
1answer
83 views

How to create a grid after merging shapefiles?

Follow up question to QGIS Model Builder Script - Possible to merge layers in a folder? I think I'm missing something very obvious here but can't seem to find it. After merging shapfiles in a folder, ...
1
vote
1answer
46 views

Why is “Add feature” of the GPS Information tool inactive for some of my PostGIS layers?

Sorry If I rise it again on this forum but I couldn't find any info on limitations/requirements of "GPS Information" tool for QGIS (2.2.0) against data layers. For some layers I'm able to collect ...
0
votes
0answers
52 views

Is it possible to use custom (non-circle) buffer shapes?

I have a shapefile containing points. I'd like to replace each point by the same shape, centered around the point, like the "Buffer" tool with shapes other than circles. How can I do that?
2
votes
1answer
45 views

Where do I find additional instructions for QGIS print composer?

QGIS Print Composer has numerous complex interacting features. Scale vs paper size vs map extent vs QGIS main window map extent - locked layers - resolution - map rendering level (i.e. the scale used ...
2
votes
1answer
103 views

Can I draw free hand figures in QGIS?

I would like to add free hand drawings to my map. I tried the "Rectangles Ovals Digitizing" plugin but am looking for a free hand (not rectangle or circle) tool. Also is there a plugin similar to the ...
1
vote
0answers
59 views

Merging shapefiles to one, rearrange columns?

I am trying to merge two shapefiles which both contain polygons representing properties in QGIS 2.2. One problem is that the names of some of the columns in the attribute table differ between the two ...
0
votes
0answers
40 views

Running algorithm from Processing takes much much longer time than doing it from Qgis GUI

I have a road layer with 32000 features, and I want to find all the intersections. when I use processing->SAGA -> convert polygon/line vertices to points, it is all done in less than 5 seconds. ...
0
votes
0answers
25 views

Geocode addresses several QGIS

I am using Qgis and I have a excel file fields with direction and it fall geocode these addresses example address apartment township 1 calle 2 avenida Guatemala Escuintla 4 ...
2
votes
0answers
64 views

No tables listed in connection to MSSQL 2012 in QGIS

I've (finally) made a connection to my MSSQL 2012 database, but no tables are listed. Here's the tree view of the connection, and the connection properties: Some notes and questions: I've read ...
3
votes
2answers
154 views

Combining MS Office with GIS

I would like to incorporate MS Office into my GIS program. I have been using QGIS and was wondering if this would be possible? I am trying to create a one stop shop for my staff to be able to ...
0
votes
0answers
46 views

Convert to DXF not displaying correctly in CAD

I am trying to export to DXF in QGIS 2.2.0, when I import in (AllyCAD 3.6) the shape of the polygons do not match my reference shape. I presume it has something to do with projections, but I have ...
1
vote
1answer
93 views

How to get the map canvas CRS in EPSG code?

This is probably a simple request but I cannot find a way around it: how can I read from python the map canvas CRS? I know how to set it up: canvas = self.iface.mapCanvas() ...
0
votes
1answer
39 views

How do add attributes from shapefile to list of lat/long-coordinates using QGIS?

In QGIS I have a csv-file which contains lat/long-coordinates and population data for each coordinate. I also have a shapefile containing certain regional districts, in my case US counties. Now I ...
0
votes
0answers
28 views

QgsFeatureRequest and QgsVectorLayer are missing in the QGIS

I am trying to use part of my friend's code in eclipse written in Python using QGIS APIs. I have installed the QGIS 2.2.0. now before running the code, it seems that something is missing here. All ...
0
votes
1answer
35 views

Conditional formatting of grid cells based on specifict attribute

I'm using QGIS. I have a 29x30km grid. Every cell of the grid has its ID and every cell of the grid has an attribute "Population" ranged from 0 to 30000. What I would like to do, is to get some kind ...
2
votes
2answers
114 views

Auto fill second column with predefined names depending on first column (QGIS)

I want to create a point layer. In the attribute table I want to have two columns. In the first column I want to type an abbreviation like A. Then I want the second column to be auto filled with ...
1
vote
1answer
58 views

How to open most recent directory using PyQGIS?

For example, when I add a vector layer, next time that I want to add another layer it opens up where I chose my last layer from. How would one implement this in Python and/or PyQgis? I'm writing a ...
0
votes
1answer
48 views

Changing $id in a shapefile in QGIS

I need to change the id (feature.id() in the python API or $id in the field calculator) of for features in shapefile layers in qgis, and I need to do it in Python. Is there a way? I tried something ...
0
votes
1answer
66 views

Georeferencing PNG against Google maps with openlayers plugin

I am trying to georeference blueprints to the footprint of a building. I'm using the Google Satellite image from the plugin to do this. The blueprints are rotated about 30 degrees. When I run the ...
1
vote
1answer
150 views

ToolBar icon images missing

very early build ~ zip file I am getting blank outputs for button images in a custom toolbar. Although the button information populates the dockable toolbar, they lack respective icons [see Fig.1] ...
1
vote
1answer
126 views

QGIS Model Builder Script - Possible to merge layers in a folder?

I would like the user to select a folder via the interface in which all the vector shapefiles inside that folder would be merged. I have been using the Model Builder and looking at example scripts ...
0
votes
0answers
26 views

How to do the “display route events” from Arcgis, in Qgis

I'm working with Arcgis 10.1. In Arcgis there is a feature called "display route events" from tables, and I want to do exactly what that features does, but in Qgis. I'm using Qgis 2.0.1. What this ...
0
votes
1answer
91 views

What is the best way to manage geodata with open source software?

We are a small group of GIS users with different expertises embedded in an administrative infrastructure attempting to switch to a small and low cost open source infrastructure (open source GDI). ...
1
vote
1answer
122 views

QGIS 2.2 Print Composer does not display map with some datasets

I can't seem to get the Print Composer of QGIS 2.2 to work. When I click on "Add new map", the map square is created, but I can't seem to see my data in it, whatever the scale I use or even clicking ...
3
votes
1answer
111 views

QGIS - Is it possible to increase Output Field Name?

When creating a new Column, the default value for the length of the name is 10. Using the Field Calculator via the Model Builder, I want to include the names of regional areas into the columns which ...
0
votes
0answers
38 views

v.buffer angular buffer doesn't take all the polygons into account

I am trying to create an angular buffer around building footprints with the v.buffer command (QGIS 2.2). There is no error message, but the algorithm doesn't take into account all the buildings. This ...
1
vote
1answer
75 views

How to change attributes with QGIS python?

I have this piece of code which I would like to use for inserting values into column. It does not throw an error, the changes are not written to the source (shapefile). from qgis.utils import iface ...
0
votes
0answers
47 views

Determining whether point location is left or right of line?

I have one line layer and one point layer. Points are located both sides of line. I want to know whether points are located on the right side or the left of the line. Is it possible to determine ...
1
vote
0answers
36 views

Command Line alternative to using QGIS GUI to save a Raster as a Rendered Image

I have a raster image in PNG format which I can open in QGIS but not in Windows Picture Viewer. To do that i figured out that I have to save my raster as a 'Rendered Image' from the 'Save As' (option ...
0
votes
0answers
41 views

QGIS labels are different on canvas, composer and from PDF

I am running QGIS v2.2 off a 64 bit Windows server. I have created a map with a number of local government area polygons, road polygons (to which I have applied a Layer Source to limit the labelling ...
1
vote
0answers
39 views

Using GeoBrain WCS4DEM in QGIS?

I added the GeoBrain WCS server to the server list: http://geobrain.laits.gmu.edu/cgi-bin/gbwcs-dem?version=1.0.0& I connect to the server and get a list of layers. I select the first one listed ...
1
vote
1answer
51 views

QGIS Road graph setting not configure

I am using qgis valmiera on windows 7 pro 64 bit. I am unable to configure road graph setting. Layer feature Transport layer is not highlighted. Please tell me how to solve this problem. Please tell ...
1
vote
1answer
123 views

Rasterizing polyline data with QGIS/GDAL: custom line width

I need to make a raster from a polyline shapefile. However, when I use gdal_rasterize (either directly or through QGIS), all my lines are drawn one pixel wide, while I need them to be drawn with the ...
0
votes
0answers
97 views

QGis, how to overlay and correctly position and scale a KML and image onto a Google base map

Being totally new to the entire GIS subject I managed to install and get runnning QGis (2.2.0 on Mac) properly, get my Google Maps showing (I set the the CRS to WPSG:3857) and I also got my KML file ...
1
vote
0answers
43 views

QGIS how to patch a plugin on local machine

I want to make a minor modification to a plugin (to change a field width in Table Manager). I edited the .py file and the .ui file and changed what I think are the right numbers but this seems to ...
1
vote
1answer
47 views

how to add data from a layer to postgis table with different field names

I am importing waypoints from GPS (in gpx format) using Layer>Add Vector layer and then I want to clean up the data and add some more attributes and finally add them to a master table in PostGIS. The ...
3
votes
2answers
115 views

Add rectangle polygon

I have a polygon shapefile layer. I want to add a rectangle polygon (just like in Arcmap), and another one using the previous polygon edge. I need it to be accurate, my hands do not meet this ...
0
votes
0answers
24 views

How to turn a moving agent to the specific coordinate

I have a moving agent in gis map that is going to the special coordinate. With assumption that maximum angle of rotation is predefined, I want the agent turn into specified coordinate (in moving) and ...
0
votes
0answers
60 views

Change palette of basic colors grid in 'Select color' dialog

I would like to know if there is a way to change the default palette of colors (48 Basic colors) which is displayed on the dialog "Select Color". Specifically, I want that when I add a layer the ...
0
votes
1answer
204 views

Problem with matplotlib when installing QGIS on mac

I have matplotlib installed on a Mac (Mavericks) via pip, which means the matplotlib files get installed under /System/Library/... I tried installing the most recent version of QGIS, and the install ...