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
3 views

Changing mouse wheel zoom settings in QGIS?

I'm having a problem with the mouse wheel zoom setting on my macbook trackpad. The zoom occurs far too quickly for any level of precision. I noted this comment in the dev log: 2004-08-14 [gsherman] ...
0
votes
1answer
9 views

QGIS - use atlas attribute with 'Like' command

Does anyone know how to use the new get Attribute function in conjunction with the "Like" command? I have a table with an Attribute "Sub_Region" and want to show the features that match the atlas ...
2
votes
0answers
25 views

Create “mean” line from multiple lines using QGIS

I have multiple lines features (also have them in multipoints...) representing similar path (mountain trails, in this case) with various GPS precision, resulting in many lines close to each other, but ...
0
votes
1answer
13 views

Building heights above DEM through field calculator

I have a series of building polygons which I would like to convert to a raster illustrating their height. I have the building heights but not their elevation above sea level datum. I have the ...
3
votes
1answer
61 views

“Singleparts to multipart” vs. “Dissolve”

It seems to me that the vector tools "Singleparts to multipart" and "Dissolve" do the same things. Can someone confirm this, please? Or do I overlook something?
2
votes
1answer
17 views

How to convert a RGB tiff into pseudocolor with GDAL etc?

In QGIS I have made a singleband pseudocolor image out of one of the bands from a RGB GeoTiff. I choose one band and then make a linear color interpolation (see attached image). I now want to do ...
0
votes
0answers
11 views

ArcGIS Online : 'Unable to import this shapefile (a is undefined)'

After saving a shp file from QGIS I get this error adding the shp to ArcGIS Online: 'Unable to import this shapefile (a is undefined)' I tried saving in different projections (WGS1984 (EPSG:4326), ...
1
vote
1answer
29 views

Adding items to DEM in QGIS

Working with QGIS and Grass I would like to produce a ZTV. I have the bare land DEM happily ready to go but would like to add buildings and woodland to the calculation. Can anyone please point me in ...
0
votes
1answer
21 views

How to get image pop ups in QGIS?

I have a map of an area and georeferenced photos. I need to be able to bring the pictures as points and then be able to click at a certain point and an image pop up.
1
vote
0answers
13 views

In qgis using python, how can I get multiple pixels from a raster based on a vector point file

I just started working with qgis, and for the life of me I cannot figure out how to solve this problem: I have several points of interest, these are stored in a shape file (just simple points). I ...
1
vote
1answer
22 views

SVG from QGIS to Illustrator CC gets wrong stroke widths

When I export SVG files from QGIS using the Print composer the stroke widths become a lot wider when importing into Adobe Illustrator. It seems like the stroke width in the SVG translates differently ...
0
votes
0answers
6 views

saga:slopeaspect curvature

I'm using windows 7 on 64 bit and using Qgis 2.6.0.I'm trying to process some Tifs from the console using the processing toolbox and saga:slopeaspectcurvature. This is pretty much how my code looks ...
1
vote
2answers
39 views

How to merge shapefiles with the same attributes?

Let's say, I have two shapefiles, a.shp and b.shp, containing point features with the follwing attribute tables: a - id att1 att2 ----------------- 1 1 1 2 2 2 b - id att1 ...
2
votes
0answers
20 views

“Georeferencing” lidar data to accurate survey

Often I obtain LIDAR data for concept studies and conventional survey (in dxf format) over a small portion of this. The LIDAR typically covers the broader area and is used for broader studies, ...
0
votes
0answers
13 views

How many Print Composers in a project before its too slow

We are using Print Composer in QGIS 2.6 to print map insets at specific locations, these have all been created and saved in the project. The project now takes a long time to just open, has anyone ...
0
votes
0answers
31 views

Multiple Labels from attribute column in QGIS

I was wondering if there is a way to have multiple labels from a joined attribute table in QGIS. I have two tables, a polygon table, and a table with words (codes). The codes table can be joined by a ...
0
votes
0answers
8 views

mysql data automatically updates

Is my sql data automatically updated in qgis? We have connected the mysql with qgis but data is not updated automatically. Is there any other way to connect the datasource with qgis?
0
votes
1answer
16 views

Read ellipsoid parameters

I would like to retrieve the semi-major axis of ellipsoid of a layer (any layer) using Python API. It seems that crs class can read only the ellipsoid acronym (?) Apparently, QgsDistanceArea class ...
0
votes
1answer
77 views

How to use shapefile in QGIS on Debian?

I am extremely new to GIS and I just received a shapefile, as a zip file that includes the following files: filename.SHX filename.SHP filename.prj filename.dbf filename.cpg but I am not sure how I ...
1
vote
2answers
29 views

What are QGIS Arcpy Equivalent Functions for MakeFeatureLayer and SelectLayerByLocation?

I have a script that I had created using ModelBuilder, but our field personnel use QGIS 2.0. Below is a snippet of the code. I am wanting to know if there is an equivalent using pyqgis so that I can ...
0
votes
1answer
17 views

QGIS Print Composer - SVG output displays objects outside the frame

On Windows 7. QGIS 2.6.0 from OSGEO network installer 64bit (and checked with latest dev version) I am preparing a print composer map displaying only vector data (shp). Data in the map canvas and the ...
0
votes
2answers
28 views

How to obtain data to create average precipitation in 2012?

I am currently doing a final project, which I have to create a map of 2012 average precipitation of lower 48 states by using natural neighbour interpolation. The problem is that how can I get the ...
0
votes
0answers
11 views

Export to Oracle using QGIS

I have loaded a shapefile into QGIS and I now want to export it into our Oracle Database and add SDO_GEOMETRY. Is it possible to do this directly in QGIS? If not, what opensource options do I have to ...
0
votes
2answers
14 views

Remove sections, defined by a line or polygon, from a raster in QGIS

(QGIS 2.6.0 on Windows.) I have created a raster layer of heights using the TIN interpolate function. I also have another raster layer with more accurate information on the height of particular areas ...
0
votes
0answers
47 views

OpenLayers and GeoJSON

there! Recently I started learning Openlayers 2x and I've been struggling for a while now with a GeoJSON and it's projections. So, here is the deal; I successfully added wms layers from ( ...
0
votes
0answers
14 views

QGIS formatting problem using POSTGIS (datetime)

I want to use the time manager plugin using data from a PostreSQL-db. In there the time stamp is set up as follows: "[...]to_timestamp('2014-10-21 00:00:00', 'YYYY-MM-DD HH24:MI:SS')::timestamp ...
1
vote
3answers
25 views

How can I display a symbol to a specific attibute in QGIS

I have a point shapefile, where I categorized my waypoints with attributes (schools, toilets, etc) and I would like to display certain attributes with specific symbols. How can this be done? Thank ...
1
vote
1answer
13 views

QGIS geojson vector layer

When I add vector layer to QGIS using geojson protocol, data form server are being displayed. Problem is that every change of map extent (pan, zoomIn, ZomOut) is causing request for same data again. ...
0
votes
1answer
29 views

Crop one shape file using another shape file in QGIS

In QGIS 2.0.1, is there a way to automatically slice up one shape file and export it as multiple files using polygons defined in another shape file? I have a detailed shape file that categorizes the ...
1
vote
2answers
28 views

Exporting GIS Images with Transparency

I'm trying to export some images of Gulf of Mexico infrastructure that will later be used for non-GIS purposes as overlays onto sea current/weather maps (likely in photoshop). I have no clue how to ...
0
votes
1answer
19 views

Copying the numeric portion of an address to a new field

I'm attempting to copy just the numeric portion of a street address into a new table using the Field Calculator in QGIS. The expression I'm trying to use is: left( "SITE_ADDR", strpos( "SITE_ADDR", ...
0
votes
0answers
28 views

QGIS crash when I try print geometry

I do (It`s work): from osgeo import ogr inputds = ogr.Open(r'c:\temp.shp') inputlyr = inputds .GetLayer() for i,feature in enumerate(inputlyr): print i, feature.GetGeometryRef() Output: 0 ...
0
votes
0answers
11 views

How to get linestringe from kml into shp or postgis [duplicate]

Im looking into extracting linestrings from a kml file into a shp file or postgis db. Each linestring would be a feature/row. How would I go about it usinge ogr2ogr or python? I'd like to get ...
0
votes
0answers
22 views

How to save geopackage gpkg file with QGIS

I read about the new geopackage file which shall have the potential to be the shapefile of the future. But i can't find a way to save a file in QGIS as gpkg. In ArcGIS it might be possible. I would ...
2
votes
0answers
26 views

How to edit metadata in QGIS

What possibilities exist to edit metadata in QGIS? I did only find the plugin Metatools which is experimental and did not work for me. So are there other possibilities than Metatools? -In Metatools I ...
3
votes
3answers
154 views

Create fishnet grid in QGIS

Anybody have recommendations for creating a fishnet shapefile using QGIS? The equivalent task of "Create Fishnet" in ArcGIS.
1
vote
0answers
36 views

Creating an irregular points grid — one with regular along-slope distances

I am currently using QGIS to try and prepare a series of equally spaced -- along the terrain slopes -- sampling points within various NVC (National Vegetation Classification) sites in the UK. I am ...
1
vote
0answers
14 views

Python problem during CADInput installation

I was trying to install CADInput (version 0.60) on 2.4 Chugiak and 2.6 Brighton as well. In both cases I got an eror message during installation. For me the following extract of that message might ...
2
votes
2answers
39 views

QGIS calculates main soil type of polygons from another polygon layer

I've been working with qgis for a while but somehow I never fiured this out, so I thought it's time to ask. I have 2 shapefiles. a polygon layer from nearby fields (SHAPE1 (the red outlines)) a ...
0
votes
0answers
19 views

Delete shapefile object

I have a shapefile layer which comprises of a series of lines which represent archaeological features. I cannot delete individual lines as the delete button is greyed out. Is there a way for me to ...
2
votes
1answer
27 views

QGIS Plugin to add point to map without creating a file

I am looking for a QGIS Plugin to add a point to the map by entering it's coordinates. The point should only be there temporarily (as long as the QGIs project is open) and not be saved in a file.
0
votes
0answers
27 views

QGIS 2.4.0 Setting raster layer to singlebandpseudocolor using minimum and maximum raster values

I am using QGIS Chugiak 2.4.0, and I have some code in which I want to: Add raster layer to map canvas Look for the minimum and maximum raster value Apply singleband pseudocolor render type for the ...
3
votes
0answers
57 views

Why do each of my buffer-polygons have different areas

I`m using Qgis 2.2 and 2.4 and loaded a wms-map using the coordinate system ERTS89 UTM 32N. I set 8 points (all in on shp-fileand in UTM 32N) on various locations on the map. After that i created a ...
0
votes
0answers
11 views

Using attributes in the label of print composer

In QGIS 2.6 I have a problem similar to this post How to set field values as labels in QGIS2 Print Composer in that I want a label box in print composer to display the attributes of the first feature ...
1
vote
1answer
27 views

What is the expression for getting a subset of characters in QGIS Field Calculator?

I have a column of 10 character names e.g. L3NAM1988K. How can I delete the first 5 characters and the last 1 character using an expression in the QGis Field Calculator?
0
votes
0answers
12 views

QGIS 2.4 under Debian behind a proxy Plugin Repository

i'm having a problem to connect the official QGIS Plugin Repository in QGIS 2.4. I'm working in a company which uses a proxy to control web access. The plugin repository is available over the proxy ...
2
votes
1answer
41 views

What is the fastest way to digitize features on a map?

I'm currently using QGIS basically to trace a bunch of polygons to show individual ponds from google maps. Some of the geometries can be pretty oddly shaped and using the nodal digitizing tool gets ...
0
votes
0answers
17 views

How to save SQL-like WHERE as .qqf in QGIS 2.6?

I used to use QGIS 1.7.4. And there was "advanced search". I can save SQL where clause as .qqf. But I installed QGIS 2.6 and I cannot find this kind of things. Could you please teach me how to save ...
0
votes
0answers
21 views

Print Composer QGIS 2.6, how to expot image?

When i finish map in print composer and click on Export to an image format and after i go to folder where i saved it there is no image. If do same with Export as PDF i get PDF file but cant open it ...
2
votes
0answers
26 views

Percentage cover using QGIS?

I need to calculate the percentage of coral cover (polygon layer) in a 1 km radius around each record of fish (point layer). There’re about 4000 points (blue squares in the image). I am new to QGIS so ...