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

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3answers
24 views

From PostgreSQL to QGIS

I have conected to PostgreSQL and imported the layer to QGIS. The names of columns are written using English letters. Can the names of columns be automatically renamed using another language?
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0answers
7 views

Deleting unconnected lines qgis

I am using a roads map in shapefile format in order to calculate a route between two points. The map is downloaded from openstreetmaps and it has small unconnected lines that are messing up my ...
1
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1answer
96 views

QGIS 2.2 Raster Merge losing color data

I'm trying to merge a couple of GeoTiff maps using Raster > Miscellaneous > Merge but the merge is only coming out in grayscale. The geotifs are using palettes color. How do I get the merge to keep ...
1
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1answer
7 views

Data defines symbology in QGIS

I have to make a symbology based on a unique color value so I add a plus column to the attribute table with the number of color values. I went to the layer properties - style - data defined properties ...
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2answers
22 views

How to extend grid lines (Survey traverse lines) created by vector grid tool in QGIS?

We have a polygon. We want to create a grid (sort of) with certain intervals, lets just say - 200ms. In QGIS, using "Vector grid" option we can do this. But, once it's get clipped, it's like Fig -1. ...
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0answers
12 views

QGIS polygon areas inside a polygon

I'm having hard time doing the following analysis in QGIS: I have watershed polygons with individual IDs. Then I have four different shape files, each having different land use polygons. I would ...
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0answers
12 views

QGIS plugin for geodesy tasks [on hold]

Are there any plugins in QGIS for solution of geodetic problems, construct serif?
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0answers
8 views

How to Interpolate very large datasets in QGIS

I am working with a very large set of point data, (XYAttribute) which I wish to display as a raster. I've been using Interpolate, this is successful but very slow. I have other programmes that simply ...
1
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0answers
13 views

Performing buffering and intersection with script in PyQGIS

I wrote a script that performs the intersection of two layers: The first Layer -> layer1, represents the rivers The second Layer -> layer2, represents a set of circular dots distributed in a ...
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0answers
14 views

Clipping between features within a single vector?

Is it possible (via the Qgis API and friends), to clip polygonal features within a single vector layer? The hope is to accomplish this without having to duplicate the feature into a new layer. ...
0
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0answers
49 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 ...
2
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3answers
50 views

How to measure correct distances in a project with OpenLayers background?

I have 3 lat/long points as follows: A = {35.257246,139.721256} B = {35.256541,139.721491} C = {35.256326,139.7203271} 1) Measurement result by Movable Type Scripts: By using the distance ...
40
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15answers
6k views

Where can I find QGIS tutorials and resources?

After several recommendations, I thought I'd familiarize myself with the capabilities of QGIS. I downloaded the program, but apart from basic loading of data, I got lost (the help file wasn't much ...
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1answer
13 views

Tiled raster image to be placed in an OSM/ Leaflet.js map

I have a mapoverlay in a custom projection which I need to add as a layer to an Openstreet map within a website. Since I was not able to change the projection earlier, I decided to manipulate the ...
4
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1answer
1k views

Union, Dissolve, Buffer — multiple layers, all in one step?

I'm a new user of Quantum GIS (1.7.3) and I need to repeat a task multiple times, so I'm wondering if there is a quicker way to do the following (with three or more polygon layers - each layer has a ...
2
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2answers
27 views

Layer just for annotations

Im relatively new to QGIS and would like to know whether or not I can save my form annotations to a layer so I can turn them on or off.
1
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0answers
28 views

How to extract elevation data from ASTER/SRTM? [duplicate]

I just want to know if there are any other tools available in QGIS apart from the Point Sampling tool to extract elevation data from ASTER/SRTM/CartoDEM (for India) data? When I convert these images ...
3
votes
1answer
14 views

QGIS 2.2: prevent labels being cut off / clipped at edge of map

I've read a few other issues about trying to prevent labels from rendering if they run off the edge of the map canvas. This is particularly a problem in Composer, where I get lots of country labels ...
1
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0answers
8 views

QGIS 2.4: make an image-to-image registration to link the 2 images (RGB AND NIR)

I have 2 images (RGB and NIR) in png form from field and i need to link them together somehow to be able to see the overlapping areas, and cut out the wrong ones. How to do this with QGIS 2.4.0
4
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4answers
2k views

Where can I download the exercise data for The Free Quantum GIS Training Manual?

Where can I download the exercise data for The Free Quantum GIS Training Manual? The pdf of the manual just mentions the sources of the data, but doesn't give any links.
2
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2answers
89 views

Open Arabic Shapefile in Qgis

I have a shape-file all it's fields are in Arabic. When I opens it in qgis 2.0 all the data is replaced by "?". I changed the encoding to Arabic or UTF-8 but with the same result. How can I Open an ...
0
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1answer
79 views

Open multiple hyperlinks in one point directly from QGIS?

I have an enormous shapefile and each point has about twenty different attributes. About five of these twenty are hyperlinks- is there anyway to open these directly from selecting a point in QGIS? ...
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0answers
13 views

Working with Fulcrum data in QGIS

I have been sent some shapefiles, gathered using the Fulcrum app. However, when I load them into my project on QGIS 2.2, they wont display. They will display if I go to 'Zoom to Layer Extent" but ...
2
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1answer
34 views

Trying to install QGIS - missing 1.11 GDAL

I just spent the last n hours working on this, and still haven't gotten anywhere, so I'll throw it to the group. I see that other people have asked about this here and here, and I'd be happy to take ...
2
votes
1answer
41 views

Memory Vector Layer Corrupted?

I was working with a large data set that had data for roads, rivers, railways, etc. all together so I decided to break the different data out so I could label it differently on the map and check each ...
2
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1answer
40 views

QGIS 2.4.0 How to display only selected features on map?

Not sure if this option ever existed, but the new QGIS version hides a lot of things somewhere else and this seems so simple that I'm kind of convinced it was possible to do this before. I have quite ...
0
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1answer
100 views

distance difference in Google Earth with exported GPX or KML compared to source shapefile

I've converted a shapefile (points) to KML with QGIS. Points in the shapefile are within 100m distance from each other. When I measure it in Google Earth, the distance changes to 80m. The same ...
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0answers
17 views

Query PostGIS database without creating primary key [on hold]

I'm trying to query PostGIS database from QGIS DB Manager: select row_number() OVER(ORDER BY idx DESC) as id, p.*, * from table_1 join table_2 as p on "name" = "name" where row_number() OVER(ORDER ...
1
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0answers
32 views

Join/append multiple, identical polygon layers into a single layer whilst retaining all attributes?

I have run some analysis (zonalstats) on different raster layers using the same analysis polygons. I want to concatenate all these different layers together, i.e. retain a single polygon and have a ...
3
votes
2answers
55 views

Merging raster and vector not working

I have 1 vector layer (counties) and 1 raster layer (population density). I have tried merging these two, so that I can examine population density within a county, but I have had no luck. It just ...
5
votes
1answer
79 views

How to create a storm swath map?

I can't really find the words to explain what I'd like to achieve so I attached a picture. The top picture was made of two layers, the layer with circles was made/styled using the instructions from ...
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2answers
99 views

How can I see average of raster value over certain area, marked by mouse?

I have a raster in Quantum GIS and I am just exploring it. How can I see average of raster value over certain area, marked by mouse? In other words: How can I select particular area in QGIS? How can ...
2
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0answers
51 views

QGIS 2.4 Processing (Zonal Statistics) error

In QGis 2.2 all my models (processing model builder) are working fine. When I start the same models in 2.4 I get errors like this: Prepare algorithm 5: Zonal Statistics Running Zonal Statistics ...
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0answers
74 views
+100

Startup python script to re-join layers

In QGIS 2.2, there is a bug which involves using the JOINS properties on a vector layer (that is already being joined with several other vector layers) whereby the attributes are not fully loaded. ...
8
votes
1answer
1k views

One to Many Relationship in QGIS with PostGIS

Does anyone know of any tool that can do a One-to-Many relationship in QGIS. I have my data in a PostGIS database. I would like to be able to query spatial layers that are related to spatial or non ...
6
votes
2answers
168 views

How to sample a 3D raster along a 3D path (or 4D raster along 4D path)?

I have a 3d raster dataset of atmospheric variables (lat x lon x altitude). I would like to sample this raster dataset along a 3d path. Any idea how I can achieve this, preferable with qgis or ...
4
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2answers
1k views

QGIS Server limitations?

QGIS Server seems to be fairly simple to setup and create services, however I'm wondering if there are any limitations with using it opposed to MapServer or GeoServer. My current server ...
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0answers
22 views

How to import PDF which has vector format into QGIS's vector layer? [duplicate]

I know the way to convert an ordinary raster pdf into QGIS. But is it possible to import a pdf which preserved the vector format (e.g. the pdf files exported by AutoCAD) to QGIS's vector layer?
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3answers
44 views

How to delete horizontal lines from a vector grid?

I have a 250ms vector grid which covers an area of 88 Sq.kms. For surveying purpose, we would like to retain the vertical lines alone. Is it possible to delete all the horizontal lines from the grid ? ...
2
votes
1answer
30 views

QGIS way to import OSM/Google Maps but remove or exclude extraneous areas, limit geographically the use of OSM

GIS Newbie question, perhaps: But I am looking to place an Open Street Maps/Google Maps layer underneath the rest of my shapefiles for referencing purposes. Let's say for instance, that I am looking ...
3
votes
1answer
27 views

Why GRASS 7.0.0 can't create a table while importing shapefiles from QGIS?

I use GRASS7.0.0Beta1 and QGIS 2.4.0 on Windows8. With v.in.ogr, when I import a shapefile, I get the error message "Unable to create table". When I put the option of not importing the table, the ...
1
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0answers
19 views

Free And Open Source Software Tools to orthorectify Pleiades imagery [duplicate]

Are there Free And Open Source Software Tools to orthorectify Pleiades, Worldview And Quickbird imagery as we do with COST tools such as ERDAS Imagine, PCI, ENVI, etc.?
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0answers
21 views

Postgis / QGIS Snap Point to Line

I'm trying to snap points to lines in postgis for use in QGIS, but cannot get it to work. I have one line in my line table (although it was created by merging multiple lines together) and about 600 ...
1
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1answer
99 views

Qgis 2.2 error plugin manager/installer error

I get this error at startup Ocurrió un error durante la ejecución del siguiente código: import pyplugin_installer Traceback (most recent call last): File "", line 1, in File ...
1
vote
1answer
109 views

How do I get the vector output segmentation algorithms to work properly in QGIS 2.0?

I'm trying to run the Watershed Segmentation algorithm, specifically, but I have been receiving the same error message using any of the available segmentation algorithms. I'm new to QGIS and have been ...
1
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0answers
22 views

QGIS 2.4.0 Mac Yosemite compatibility

I just upgraded to the Beta 2 version of MacOS 10.10 ("Yosemite"). I'm getting an error when I try to "drag and drop" shape files into QGIS. I'm running QGIS 2.4.0, GDAL 1.11, and MATPLOTLIB 1.3.1. ...
0
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1answer
132 views

Pull pixmap image source from ui edit text in QT

I'm putting together a custom form for QGIS identify using Qt Designer. One attribute has a file name to the accompanying photo of the feature. I'd like to have the photo label in the form grab the ...
1
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1answer
89 views

How to scale with radius attribute

new user of QGIS. I would like to style vector data based on an attribute (radius). The actual unit is in nautical miles. I don't want to use size-scale field or buffer to style the point rather I ...
3
votes
1answer
74 views

Draw lines between two points in QGIS

I have an excel (Fig) which has both X & Y in projected coordinates (WGS84/UTM). Is it possible to draw lines between the X & Y in QGIS ? I've tried to create points based on X,From_y and ...
0
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1answer
38 views

How to add new columns with attributes in existing Qgis layer?

How to add new columns with attributes in existing Qgis layer? Doing the "same thing" here described