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

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3
votes
2answers
52 views

Select polygons that do not intersect any other polygon using QGIS, GRASS, SAGA or R

I would like to select the polygons of the layer below that do not intersect with any other polygon (within the same layer). How can I do this using QGIS, GRASS, SAGA or R?
0
votes
1answer
23 views

Run ftools multiparts to singleparts from PYQGIS

Is it possible to run the multiparts to singleparts function from the console with the processing_runalg function? Or is there another way?
0
votes
1answer
39 views

How to copy attribute values of fields in selected features of one layer to another Qgis programmatically?

I am trying to get the values of attributes of the selected features of a layer field by field and copy to another layer that I created in qgis with pyqgis. Is here a example for this. Every example ...
0
votes
1answer
53 views

Free/Open-Source Archaeological Geophysics Programm?

Does anyone know a free/open source software or a GIS plugin for working with archaeological geophysics data, especially for data from a magnetic survey (magnetic gradiometer map)?
0
votes
1answer
22 views

Summing the number of intersections with a separate buffer layer

I have dabbled with ArcGIS and QGIS a bit, and I consider myself a self-taught beginner with a whole lot to learn. So, I have two layers: 1) census blocks, and 2) point data. My goal is to calculate ...
0
votes
0answers
30 views

joining polylines on geometry and attribute

I have dowloaded an Open street Map shapefile containing streets and their attributes, for my whole country. I have qgis and spatialite_gui and a very basic understanding of SQL The problem I have is ...
0
votes
0answers
7 views

shifting/seperating overlapping polygons into several smaller polygons within the same sapce (QGIS)

I'm using QGIS and have shape files from the City for parcels of land. There are a few apartments and condos in which the parcels have not been separated - i.e., instead of a dozen small rectangles ...
0
votes
0answers
29 views

Help with scripts for processing raster files with the raster calculator in QGIS

I am trying to process some raster files using python scripts in Qgis 2.20, and I have been having trouble finding any documentation on using raster calculator in scripts being run in the processing ...
1
vote
2answers
16 views

Create a common scale for different raster layers in GRASS, SAGA or QGIS

I have a number of layers that represent the temperature variability of the water in a lake. They have been generated trough interpolation and have different values as they represent temperatures ...
0
votes
1answer
27 views

Globe on my Qgis doesn't work.

OS : osx 10.9.2 * I just operated a clean osx installation. Globe have never worked since I started to learn QGIS. When I tried globe, it terminated QGIS then a message(see below) occurred. Any ...
2
votes
1answer
55 views

Problem installing QGIS Valmeira on Windows 7 Professional 64-bit

I have been having trouble installing QGIS Valmeira on Windows 7 Professional with SP1. When I installed to the default directory C:\Program Files\QGIS Valmiera\, many of the predefined coordinate ...
1
vote
1answer
18 views

Parameter values to create a vector grid with 1km x 1km cells?

I created a shapefile from WKT in QGIS using the values from this link. I want to create a vector grid with 1kmx1km cells but I can't figure out what values need to be set for the X and Y parameters. ...
1
vote
1answer
29 views

In what ways has QGIS 2.x API changed making Plugin Builder Tutorial invalid?

I am working on the QGIS workshop Tutorial for QGIS Plugin Builder and notice that it is for QGIS 1.1. As this seems like a popular tutorial, in general, what are some areas of this tutorial that need ...
0
votes
0answers
10 views

how to add layer style in geoserver using gxp_styler by GXP api

I am using GXP api(open Geo Suit) for my GIS application.I want to add style to layer using gxp_styler plugins.This plugin is working fine for me but the problem is that when i add a new style to ...
0
votes
0answers
23 views

Add existing QGIS plugin button to custom toolbar

Is it possible to add an existing plugin's button to a custom toolbar? I've succeeded in adding core actions such as shown below, but am wondering if it would be possible to integrate another plugin ...
0
votes
1answer
41 views

Identifying streets of same name where split by osm

I have a large map of every street in the country. This is a vector layer in QGIS many streets are split by OSM , IE have a different OSM ID yet the street has the same name. Often these streets are ...
1
vote
1answer
18 views

Is there a way to edit the host name of Postgis layer?

Recently I change my server to a remote host. That's means all my work there I used Postgis layers, the host name at the source is set to 'localhost' and I need to change to 'remotehostname'. The ...
0
votes
2answers
43 views

Have I created a valid Spatialite database?

I didn't manage to find the better way to populate the exisiting Spatialite database with new computed data than just creating new columns and filling them in the Python script. You can see that the ...
0
votes
0answers
17 views

Calculating rows in a attribute table of a point shape with QGis or Saga

I have a point shape with an attribut ("test"). I need to calculate the sum of the 1st four (id 1-4) "test" values and then the next 4 (id 5-8). Is there a chance to calculate this with the field ...
2
votes
1answer
34 views

Why this two datasets don't match?

I have a postGIS database in SRS 4326 (WGS84) with several Europe layers working well, but when I load a shapefile projected to the same SRS with QGIS, the layers don't match. To explain it better ...
1
vote
0answers
10 views

Can QGIS2 refresh layers without the need to reclassify each layer individually?

I have a set of layers which I'd like to have refreshed each time I open QGIS2.2.0 (Windows 7). Each of 14 layers (polygons) is linked via a join to a csv file with no geometry. The layer displays a ...
0
votes
0answers
23 views

Mapnik: GeoTIFF flipped (mirrored vertically)

I generated a GeoTiff using the QGIS HeatMap plugin and want to render it on top of some OSM data. The problem is that the raster gets rendered upside-down in the output. Can someone point me in the ...
1
vote
0answers
18 views

qGIS' Database Manager “Load as New Layer” Option Not Working

I'm trying to visualize some of my database queries on qGIS. I run a valid SQL query which returns a subset of my table that should be easily loaded as a layer. I then check "Load as new layer," ...
2
votes
1answer
22 views

Update/refresh edited PostGIS table in QGIS

I imported a PostGIS table (with geometry) from my PostgreSQL database as a layer in QGIS. Later, I edited the table using PostgreSQL UPDATE commands. Is there a way to quickly update (like a refresh ...
0
votes
0answers
28 views

How to add the attributes of selected features to my new layer in pyqgis

I am trying to create a layer from the selected points coordinates. I am drawing a circle to the coordinate of selected points. I also need to add initial attributes of my selected features to my new ...
0
votes
0answers
37 views

Problems with projections in QGIS 2.2 on a Windows Vista? [duplicate]

I use QGIS 2.2 on Windows 8, and the same QGIS 2.2 has been installed on a computer with Windows Vista. On the Windows 8 everything works just fine, but something is wrong on the Windows Vista. All ...
0
votes
1answer
32 views

Draw lines from points in QGIS

(I found here similar questions but they all reffer to ESRI's programs, and I use QGIS) I have a point layer and need to draw a line passing through or in the vicinity of the points (up to 0.5m ...
0
votes
1answer
30 views

How to change polygon display/symbol properties in QGIS while digitizing?

I have two questions. It would be great if anyone help me to sort this out. Thanks in advance 1) While capturing a polygon in QGIS, how to remove the red - shade - sort of thing..... ? 2)Though the ...
0
votes
0answers
19 views

EDGE Detection of sst & Chlorophyll image [closed]

Is there a tool in QGIS that automatically identifies fronts in SST image and concentration in Chlorophyll image.The tool what I required should be work similar as Cayula & cornillon tool ...
1
vote
0answers
43 views

How do I smooth edges of polygons in QGIS?

Is there a built in function or plugin I can use to achieve smooth lines for my polygons instead of the blocky ones I have now?
2
votes
1answer
32 views

How do I make this into a working CRS in ArcGIS?

+proj=tmerc +lat_0=0 +lon_0=-114 +k=0.9999 +x_0=0 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs I have this text string which I successfully used to project data in QGIS. How do I use ...
3
votes
2answers
37 views

Why do I get an empty shapefile when converting this KMZ in QGIS?

I have downloaded a KMZ file containing global elevation information. I have tried to convert the data to a shapefile using qgis (save as shape option) and using the zonum solutions website but both ...
1
vote
0answers
29 views

Converting QGIS Labels to a Polygon Shapefile

I am trying to create an annotation feature from labels and then export this out as a polygon shapefile (the resulting shapefile can then be loaded into ArcGIS online to basically have labels without ...
1
vote
2answers
54 views

Conversion of point grid to a raster with open source tools (Gdal, QGIS …)

I'm looking to do something which seem simple to me, but I haven't found a solution since 2 days I looked for. I've got a Postgis DB with lot of points (WGS84) spaced of 100 meters which cover a ...
0
votes
0answers
14 views

Multiparts and Multigeometries: checking for multigeometries with PyQGIS?

I have been working with PyQGIS and writing a small script to check whether the layers I have in the MapCanvas have geometries of type "MultiXX" because I want to run the "Multipart to Singleparts" ...
2
votes
1answer
31 views

How to fix “The selected file already seems to have a world file!” when image hasn't been georeferenced before?

I am georeferencing historical aerials from 1988 in QGIS 2.2.0. Sometimes it works perfectly and other times after I have places my points and start the georeferencer a window pops up saying: "The ...
0
votes
0answers
13 views

How to cut a polygon without snapping to a vertex?

I am familiar with editing polygon files in QGIS version 1.8. I have recently upgraded to version 2.0 but there seems to be a difference in the way it processes cuts. I used to be able to cut a ...
0
votes
0answers
15 views

How to rasterize a point layer? Cell value should be 1 if feature attribute is 1

I’m a fairly experienced GIS user, but I’m new to QGIS. I’m using version 2.2, and I’m trying to convert a point data layer into a raster data layer using the Rasterize tool. The point data layer has ...
0
votes
0answers
12 views

In QGIS Process Modeller, is it possible to automatically run a function on several layers without listing all combinations?

Trying to develop a Model which includes finding any intersections between layers and then merging them all into a single layer. I have 12 layers in total, it's not really efficient to list all the ...
0
votes
1answer
48 views

How to create input data for the LRS plugin from an excel table without coordinates?

I'm working with QGIS 2.2.0. I want to add a shapefile from an excel file that has informations I want to use in the LRS plugin. The excel file has no geographic information. Every time I try to save ...
0
votes
1answer
33 views

How to join information from an excel table to a road feature in QGIS?

I'm working with GQIS 2.2.0 Valmiera. I've made a shapefile of a road that consists in a single line. Now I want to add information that I have in an excel table about several point in the road. How ...
2
votes
1answer
53 views

Why does QGIS 2.2 Atlas not work?

I have problem with atlas generation in QGIS 2.2. I'd like to export pdf map with 2 maps window and use coverage layer function. Atlas doesn't iterate across the features in coverage layer. First ...
-1
votes
1answer
46 views

Can QGIS alone can be used without installing grass?

can QGIS alone can be used without installing grass? i want to use functions of grass and i am not interested to create mapset and all. just with raster and vector files, i want to study temporal ...
0
votes
0answers
26 views

How to calculate the area of an ellipse on the earth's surface using Python?

I have a dataset consisting of GPS coordinates. I use a clustering algorithm to generate a two dimensional Gaussian for me. The Gaussian takes the shape of an ellipse if visualized on the map. ...
0
votes
1answer
65 views

QGis: scripting the map rendering (multiple similar maps from one shapefile)

I would like to ask for advice on creating a Python script that will provide the opportunity to render a plenty of similar maps (with the same extent, projection, layout, color scheme and composition, ...
0
votes
0answers
22 views

MSSQL Connection settings for QGIS

OK first lets get the blond elements out of the way- I'm not asking for how I connect to my actual database. What I'm asking for is an example or screen shot of the entries required when setting up a ...
0
votes
1answer
31 views

Producing gradients between shapefiles and using original boundarys as isoclines (lines)

to produce a bathmertical map of a river bed I draw shapefiles showing the different depths based on satellite images taken during different tidal levels (deepest, 2nd deepest, 3rd deepest, shore ...
2
votes
2answers
49 views

What's the use of the buffer function in field calculator?

I'm trying to find out how the buffer command in the filed calculator works. I tried to create a new field to my point shapefile (integer) with the following: buffer ($geometry, 100) but no ...
0
votes
0answers
14 views

QGIS map tip / label showing a table

I have a MSSQQL Spatiatal layer with Point data (borehole locations, pointID) and a joint table lithology (soil info per borehole, pointID, depth from, depth to, constituent) Is there a way to use ...
0
votes
1answer
18 views

QGIS 2.2 Atlas - Blank Export

I've got a map laid out how I want it in QGIS 2.2, using the "Atlas Generation" feature. When I preview the atlas, all 7 pages look proper and seem to work fine. However, I cannot export them to any ...