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

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26 views

Should i use cell registered or grid registered bathymetric data in QGIS?

I am planning on calculating habitat volume over great ocean distances and have the choice to use either Grid or cell registered data, downloadable from this link. ...
1
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0answers
39 views

QGIS Freehand editing plug-in: blocked attribute table

I can't save object after drawing by Freehand editing plug-in. I suppose it will be connected with creating some (special) column in the table. Could anyone suggest a solution?
2
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1answer
58 views

How to properly open an ASTER data?

Yesterday i downloaded an Aster L1B image from USGS's website. If i load it in QGIS, it doesn't get displayed properly(location wise). Even after i've enabled "On the fly" option, it's not reading the ...
1
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0answers
18 views

PyQGIS: Properly trigger actionPan() tool when feature is added

I wrote a plugin which creates a custom map tool that adds features. I would like to cleanly connect to the pan tool after a feature is added. I've done it in the following way and it works, but I get ...
3
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2answers
62 views

Using SVG from Wikipedia to fill polygon?

I'm trying to use the flag of each region in Italy to fill each region's polygon. I have downloaded the shapefile of Administrative areas for Italy from diva-gis and am now attempting to fill each of ...
3
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0answers
29 views

Raising raster to a power gives no data values

When performing the following operation in QGIS Raster calculator: 10 ^ (("20091201_20100101_chl_modis_malvinas_ns@1" * 0.0000581)-2) I get no dada values for every cell where I should get < 1, ...
1
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0answers
27 views

Tables from SQL Server to QGIS Layers

I'm a beginner SQL and GIS user and this my first time using stackexchange, so apologies if I'm asking the question properly. I'm trying to open some MSSQL tables in QGIS. I established a connection ...
3
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1answer
35 views

How to refresh the view in QGIS Print Composer using Python?

I am trying to automate the printing of maps based on different attribute classifications using Python in QGIS. Everything is okay except for when I open the printed image, the labels are blurry. ...
5
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3answers
69 views

Create a Raster file out of a ASCII grid file?

im using a special system to do geomagnetic surveys. Its software let me output the information as image files, ASCII or in its own proprietary file format. Now i want to get its information in my GIS ...
1
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1answer
43 views

How to use the % Modulo operator to select points for labeling?

I have a shape file with point numbers for individual ID's. I would like to select point numbers divisible by a number, and if the remainder is 0 then I would like to label that point. I have tried ...
1
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0answers
13 views

How to add an unknown CRS to QGIS? [duplicate]

I wonder if there is an option to add a CRS to QGIS which is not listed in the internal database of the program. I read that PostGIS allows adding a custom CRS.
3
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1answer
163 views

How to install open layers plugin on QGIS 2.4? [duplicate]

I am a new user of QGIS, and I just downloaded the version 2.4 on Windows 7/32 bits. And I seem to encounter several problems: I cannot install openlayers plugin In the "Plugins" tab under "Manage ...
2
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0answers
50 views

How to merge overlapping and duplicate lines from vector layer to one single line?

I used the "polygone to line" tool from QGis, to get a line-layer from this polygon-layer: unfortunatly this causes overlapping and duplicate lines, after I broke the qgis-export via GRASS into ...
2
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0answers
35 views

QGIS “Fill Ring” tool error on SpatiaLite DB?

I´m try Fill Ring tool on a SpatiaLite DB and I get a error on the Primary Key. The Primary Key is integer auto increment. When I insert the ring and try to save editing I receive error message ...
0
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1answer
24 views

trying to calculate volume using r.volume GRASS - error message

I am trying to calculate volume using GRASS plugin in Qgis using module r.volume however the attached error message keeps appearing. Any ideas?
0
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0answers
24 views

Export qgis vector layer to PostGIS table using python

I've created script, which does bunch of stuff, and in the end, I would like to export it to postGIS table. What is easiest way to do such export using qgis api or sth. I dont want to write SQL ...
3
votes
1answer
29 views

How to define custom projection EPSG:5714 in QGIS

I have a series of raster files with the CRS EPSG:5714. I need to define this CRS in QGIS but I'm fairly new to this and have no idea how to define the proj4 CRS for this. I searched at ...
4
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2answers
164 views

How to save .shp to .csv so that the Name is in the first “column” of the .csv?

I am trying to convert a point shapefile to .csv with locations in QGIS. The problem I am having with the conversion is mainly that, in the resulting .csv file I would like to have the Name and then ...
2
votes
1answer
31 views

How to save the edit widget setting in a style or layer definition file?

I am using QGIS 2.4 on Windows 7 installed by the OSGeo4W-installer. I want to save the "edit widget"-settings in a style to use them after loading in a different vector layer. The problem: If I ...
3
votes
2answers
54 views

Calculating flowpaths downstream of a point

I am assessing the flood risk posed by pipeline failure. I need to calculate the likely flow-paths for flood water downstream of critical locations along the pipeline using GIS. I'm familiar with ...
3
votes
2answers
87 views

Labeling only points that ends with the number 5 in QGIS

I have a shape file with points at evenly spaced intervals, the table has the following fields: Name is up to 32 characters of text. it is currently populated with an eight digit number. Point_No ...
1
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0answers
54 views

QGIS Graphical Modeler not finding output files

I am going through the GST 102 Module 5 tutorial which uses the graphical modeler. I keep getting this message when trying to use the output of an Extract by attribute algorithm as a clipper for a ...
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0answers
31 views

GDAL TMS minidriver in QGIS, problem or bug?

Its great that you can now use TMS layers in qgis! Only, my result is broken. At the 3 highest resolution zoom levels it looks perfect, but at lower resolution layers, i get mixtures of tile shift, ...
1
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3answers
74 views

polygons to polygon conversion with attribute name [duplicate]

1) I have a polygon shapefile with 1000 multi-part polygons in it. Each Row of the table is a multipart polygon. 2) I need 1000 shapefiles with 1 multi-part polygon in each. 3) Each output shapefile ...
2
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0answers
54 views

Can I export the RGB values from an ArcGIS layer symbology?

I've got a point layer in ArcGIS that has 100 specific color codes based on the name of the store. I'm trying to export the RGB values for these colors (along with the name value it's tied to) so I ...
3
votes
1answer
67 views

How to transform XYZ Raster from WGS84 to UTM ED50 Zone 34

i'm trying to convert an XYZ file from WGS84 (lat/long) to UTM ED50 zone 34. Qgis can load the file as a raster, but i cant see a way of changing the coordinate system or exporting the results as an ...
2
votes
1answer
40 views

Previous shapefiles do not show in re-opened projects

I have previously drawn a lovely shapefile in a project - all saved...good job. I open the very same project and, although the background raster maps project fine, my shapefile will not show. Zooming ...
6
votes
3answers
177 views

Cutting out depth information in raster. Calculating volume in Qgis

I am trying to calculate habitat volume for around 30 fish stocks in Qgis. I have habitat areas (shape files) and Bathymetric information (.tif file). I believe I can calculate the entire volume of ...
1
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0answers
37 views

From QGIS to PostGIS [duplicate]

I want to download my data from QGIS to an existing table in Postgresql. I tried to use DB Manager, but the field add to existing table doesn't work. Maybe somebody knows what the problem is? Or is ...
2
votes
1answer
54 views

Why doesn't QGIS automatically find the new plugin update during startup?

I have done a plugin for QGIS and I made a repository (xml) for the end users to install it. Then, I made a new version and update also my repository file with the new one but Qgis doesn't ...
2
votes
1answer
43 views

Can i combine DXF, Google Earth Models, Shape Files and Rasters in QGIS?

I'm an architect, trying to bring a number of data sets together for use in a CAD package (AutoCAD). I have some georeferenced images (.jpg, .jgw.), Some model files downloaded from GoogleEarth (.kml ...
2
votes
1answer
61 views

how to load the QGIS openlayers_plugin in standalone python script (not the QGIS embedded python console)

if I try to load the openlayers plugin in a standalone application it always fails with False, although paths are set, and plugin shows available. (tested on Ubuntu 14.04, QGIS 2.4, python-2.7) ...
6
votes
1answer
167 views

How to auto-generate map images with different styles in QGIS?

I have got a simple map in QGIS, containing only 1 layer which consists of 10+ features. Now I need to (programmatically) generate about 200 different JPEG map images of the same area. Each map should ...
2
votes
1answer
53 views

Get feature data from lat long input QGIS

In QGIS, I have a polygon dataset with feature data. I would like to extract data from this dataset using a latitude and longitude. To be more clear, I have a list of 1000 coordinates. I would like ...
0
votes
1answer
42 views

QGIS Python - Convert the CRS of an in memory vector layer

In a python script of qgis I load layers from different datasources using the QgsVectorLayer() and the QgsRasterLayer() commands. The coordinate reference systems of the data sources differs. Since I ...
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0answers
5 views

PostGIS-Layer: sql query from style rules

I’m using PostGIS layers which are build from OSM-Data (osm2pgsql). Now I like to build a sql-query to filter the needed objects like "waterway" = 'river'. But in the layer-style I already have that ...
2
votes
1answer
59 views

QGIS 2.4 Heatmap Plugin Generates a Solid Black Map

I'm trying to generate a heatmap of vehicle-pedestrian collisions in Los Angeles using data taken from UC Berekely TIMS. TIMS provides an exhaustive database of traffic accidents involving injury in ...
0
votes
2answers
34 views

How can I efficiently divide a KML file by area, while using ogr2ogr?

I have a work process which uses an ogr2ogr text command to convert a MapInfo TAB file to a KML file. I'm very pleased with this because it maintains the original symbology (a simple 2 colour system ...
0
votes
1answer
39 views

Determining the slope of a DEM (SRTM-data) in QGIS

I'm new to QGIS and I have to calculate the slope of a DEM (I use srtm-data). I already detected the geoalgorithms toolbox and I also produced a raster layer with the slope using the tool "slope, ...
1
vote
2answers
54 views

Creating a plugin tutorial

I am looking for a tutorial of how to create a plugin for QGIS. I want a tutorial that: Explains about the latest version of QGIS Working in windows environment. adequate for absolute beginners and ...
1
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1answer
32 views

Problem with projection of Slovenian Shapefile in QGIS

I hope someone can help me for this: I'm doing my masters thesis in Slovenia (in the field of wildlife management), for this I got a Shapefile of slovenian data by the University. As a main layer, I ...
1
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0answers
42 views

New sound when running QGIS 2.4 [duplicate]

I used QGIS for a very long time. In the last version, there seems be a new sound (buzz) when the program is run. Does anybody know how we can remove this sound?
1
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1answer
36 views

Error importing raster into GRASS plugin in QGIS

I am trying to import a tiff raster file into GRASS however every time I do this the below error message comes up. I am using a custom CRS so I have tried changing it back to the default CRS but still ...
2
votes
2answers
49 views

Distance from centre point to other points using QGIS?

I have a question of something I actually thought was pretty simple...I have a few points around a centre point. Now I want to know the distance from each point to the centre point. Is it possible to ...
1
vote
1answer
32 views

Setting resolution for GRASS raster

I am trying to calculate volume using the GRASSplugin. I have my area information in vector format and my depth information in raster. I read that it is important to set the raster resolution before ...
2
votes
3answers
62 views

Saving project from QGIS to CD so it can be used on other computers?

For purpose of a project, I created a project in QGIS - aerophoto base and 3 layers. It works perfect on my computer, but if I save it on CD, the project doesent work on any other computer... I saved ...
3
votes
3answers
55 views

How to divide attribute table in map composer between 2 or more pages?

Does anyone know how to divide attribute table between 2 or more pages? In exported PDF it's unfortunately clipped.
2
votes
1answer
55 views

How to get a GML overlay on Google Maps?

Anyone know how to get a GML file to show as an overlay on Google Maps? To be honest I don't know my GML from my KML, or my ETRS89 from my WGS84, as this topic is completely new to me. A bit of ...
3
votes
1answer
31 views

How to change the color of vector layer of QGIS in api?

I'm using QGIS-2.4.0 api to develop app in C++. When I add a vector layer to the app, the vector map's color would be random. I used QgsFeatureRendererV2 to get the geometry type of the layer, my ...
1
vote
1answer
44 views

QGIS Web Client zoom and scale

I have a problem with setting up zoom levels and max/min scale in QGIS web client. It looks like that values used in GlobalOptions.js file does not apply. Right now ZOOM_LEVELS is 70, maxScale 50 and ...