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

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Rasterizing Contours - How to remove 0 values

I want to convert vector contours to a DEM. From other posts, I wanted to utilise the Grass r.surf.contours tool. Initially I converted the vector contour layer to a rasterized contours using the ...
2
votes
1answer
16 views

How to install Apache Web Server from OSGeo4W?

Good morning, I'm trying to create a QGIS web client on my Windows 8 But with OSGEO4W not appear the option to make Apache installs Web Server, as of this writing in several tutorials and ...
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4answers
8k views

Is there a SVG symbol library for qgis?

Im currently using default simple symbol capabilities or dingbat fonts for point objects. Is there maybe a SVG symbol library for qgis that is a bit more extensive than that which is included? I've ...
1
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1answer
66 views

Using Engineering symbols (*.svg) in QGIS?

I was told to evaluate QGIS. It all looks straight forward except for the symbols or icons. I have created svg symbols and when I place my pointer to the obvious blank areas in the symbol library a ...
1
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1answer
12 views

date format conversion

I'am using Time Manager and QGIS 1.8.0 and I am stucked at date format conversion. Time Manager needs Gregorian format "YYYY-MM-DD HH:MM:SS.ssssss" in text field and I have thousands of records in ...
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2answers
2k views

How do I layer stack rasters in QGIS?

I have some multi-spectral data, where the individual bands are separate Raster files. How do I layer stack these rasters so that I get one raster with 3 bands instead of 3 different rasters? This ...
1
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1answer
133 views

How to get a the minimum value of a raster layer in qgis with python? [on hold]

I'm very new user of QGis and I work with landsat 5 images. In this framework, I would like to make an atmospheric correction subtracting the minimum value present in each band (1 to 4). My ...
2
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0answers
24 views

Setting up qgis web client

I have a problem with setting up a qgis web client on remote server. I set it up on localhost and it runs smoothly, but when I done exactly the same on remote server it is just not working, even a ...
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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.
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2answers
202 views

Per-pixel (statistical) calculations on a raster stack using GDAL

In R, it's relatively trivial to perform per pixel calculations based on a raster stack (e.g., get std.dev for each pixel on a 12 layer GeoTIFF). Unfortunately, the speed is less than desirable when ...
0
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1answer
96 views

Problems running model in QGIS

I am trying to make a batch model to convert band 2 and band 1 MODIS 8 day composites into NDVI. The input files are in tif format, but I want the output to be saved in Idrisi .rst format. I am ...
2
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2answers
1k views

Is it possible to use WMTS in QGIS?

Is it possible to use WMTS e.g. by http://data.wien.gv.at in QGIS? ich möchte gerne daten der stadt wien als WMTS-Layer in qgis hinzuladen. ist das überhaupt möglich? ich bin kein profi und bitte ...
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0answers
32 views

Where can I find “QGIS Training Manual” data? [duplicate]

I can't find data for this lesson in Quantum GIS: 9.4 Lesson: Supplementary Exercise. Can anybody help me?
3
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1answer
61 views

Reverting QGIS to version 2.2 from 2.4

I have QGIS 2.4 installed on a machine running Windows 7 64-bit "by accident". I was using 2.2 and when I added some package(s) it also installed the 2.4 version. Can anyone provide some advice with ...
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0answers
11 views

Gdal_sieve not working?

I'm using the Sieve command within QGIS (Raster > Analysis > Sieve), but when I run the command with any variation of parameters, it completely changes the histogram of my raster data from between ...
1
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0answers
27 views

Best Landsat band for forest classification?

Using Qgis and the Semi-Automatic Plugin for Classification, which are the best Landsat bands to use to classify trees species (in central Argentina)? In Landsat 5, 7 and 8?
4
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1answer
62 views

How do you set the position of a plugin window when you start the plugin?

I'd like to set the position of a plugin's window or dialog relative to the map canvas frame. For example, if I start a plugin, I want it to appear somewhere in the left upper corner of the map ...
2
votes
1answer
25 views

PyQGIS - Start/Stop Editing with data Provider - Commiting changes

I want to edit a specific field for a QgsVectorLayer, within a QGIS application. I am facing inconsistent results from my code, ie: changes are not alway commited. Please could someone point me to ...
2
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2answers
44 views

Help projecting Austria data with QGIS

I'm trying to reproject this dataset from Austria Statistik Geodata. Data comes in "MGI_Austria_Lambert", and I'm trying to reproject to WGS84 What I'm doing is Saving layer as... and selecting ...
4
votes
1answer
26 views

Can QGIS map canvas update while python script is running?

I want to automate a periodic refresh of the QGIS map canvas with updated shapefiles. A Python plugin or console script does not allow the map to update until the script terminates. Is there a way to ...
1
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1answer
165 views

How can I map data points to OpenStreetMap (OSM) line data?

my goal is to filter measuring points of vehicles by mapping them to streets. So I could filter out all the false data located in fields and rivers and so on. I imported my data into a PostGIS ...
3
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0answers
45 views

Creating one DEM from multiple ASC files

I am struggling with this several days and now its time to ask how to do it in QGIS. I have very detailed 27 ASC grid files with overall size of 9 GB created from 1m contours of large area (600 m2). ...
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1answer
31 views

How to increase the resolution of a 3D image in QGIS GRASS NVIZ

I'm trying to display 3D data in NVIZ within QGIS, but the result appears very low resolution in comparison to the same data in ArcScene. Any ideas as to how to improve the quality would be greatly ...
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0answers
18 views

Looking for Melbourne and Canberra metropolitan suburb shapefiles / ABS coded lists

I am looking for shapefiles or a list of suburb names for Melbourne and Canberra. I have ABS shapefiles, but I need to filter that to end up with only metropolitan suburbs. My shapefile has codes in ...
3
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0answers
34 views

QGIS field calculator expression

I am new to QGIS. I am wanting to calculate a field using other fields and some operators. Here is my expression: case When "RVM_CAT" = 'B' OR "RVM_CAT" = 'C' Then ("PC1" /100) * "RE_ha" When ...
1
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1answer
238 views

Can I prevent QGIS raster clipper from changing output cell/pixel size?

I have performed a DEM extraction using the clipper tool in QGIS 1.9.0 Master, using a mask layer, the original resolution of the DEM is 20x20 but in the resultant DEM the new resolution is ...
4
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1answer
29 views

Is there a maximum length of pdf file QGIS composer can plot?

In QGIS 2.4 is there a maximum dimension in milimeters composer can produce while exporting to pdf? Trying to produce a 3000 x 900 mm or 2800 x 900 mm map. The QGIS composer displays all the map area ...
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1answer
41 views

Show a single value related to a whole layer in QGIS

I'm developing a maximum flow plugin for QGIS. I would like to show a calculation result (i.e., the maximum flow) on the map. The result is not a property of a single feature. It is a property of a ...
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2answers
44 views

Why is the data missing in my new shapefile?

I've made a new shapefile from a part of a attribute table. Marked all the rows that i needed and clicked on "save selection as", added the new layer in my project. All the data is missing, there is ...
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1answer
326 views

Calculate area covered by a particular raster layer within polygons in QGIS

I am trying to extract information on vegetation cover within a set radius of point locations (my sites). I have succeeded in creating a new vector layer of circles with a 5 km radius around my sites. ...
2
votes
2answers
133 views

Is there a function to select a region of a map for further processing with Python?

I would like to select a map's region in QGIS for further processing with python console. Ideally I would like to select the region with a mouse drag (like Gimp crop function) and then e.g. analyze ...
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2answers
26 views

Importing DWF files into QGIS

I regularly receive files from a service authority in DWF format, which shows the location of their assets in there area. I note that there is no option to have the data in an alternate format as it ...
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0answers
14 views

Contour generation using Interpolation - Correcting edge Effects

I utilised the Interpolation feature in QGIS to prepare contours from a DEM I had generated. Sometimes when contours intersect the edge of the DEM area, they run along the edge for some distance. ...
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0answers
22 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
6
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1answer
489 views

Is there a good qml or sld file available for QGIS + Openstreetmap data?

I'm looking for a qml file (or equivalent e.g. sld) to allow me to use QGIS to take Openstreetmap data and produce paper maps. I'm re-asking this question (it was asked once or twice over a couple of ...
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0answers
16 views

OpenGeo Explorer error publishing layers to geoserver

I want to use Opengeo Explorer to publish layers to geoserver but i am getting an error report. I create workspaces with no problems and i publish styles with no problems. Can you pls help? Error ...
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1answer
85 views

QGIS: Clipping a line layer using a polygon and getting an empty shapefile

I am using QGIS 2.2.0 and want to clip a line layer (roads) so that only those inside a polygon are shown. When I do this using Vector->Geoprocessing Tools->Clip I only get an empty shapefile as an ...
4
votes
2answers
1k views

Why do OpenLayers layers appear shifted in map composer?

I'm having trouble with the OpenLayers Plugin of Qgis and the map composer: If I create an OSM-background layer and if I want to export this, the OSM-Layer looks perfectly all right in the normal ...
1
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1answer
43 views

QgsMapRenderer to export current extent using PyQGIS

I am trying to accomplish PyQGIS simple map rendering via the QGIS 2.0 Python console, but end up with only a blank image. I've followed instructions of this link. My objective is to export a simple ...
1
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1answer
21 views

Density slice/Colour slice in QGIS?

Can you do Raster Color Slices (like in ENVI) in QGIS? I.e. Where the histogram can be divided up into discrete units to represent different classes based on the values of the pixels.
0
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1answer
342 views

Reverse geocoding polygon co-ordinates?

I have a large dataset of polygons for property sections that I need to reverse geocode. It was recommended that I use a GIS like Quantam to do this however from my research I am not 100% sure if a ...
1
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0answers
31 views

Python console not working at all

My python console won't work at all. I can't open it. My QGIS version is 2.4. OS is win7 64. I've reinstalled QGIS a few times but I always get the same result. Strange. Something went wrong with the ...
4
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0answers
23 views

Workflow for adding Pipe Systems to QGIS

I want to layout a concept design for a sewer main in QGIS. I have a variety of background information: Aerial Imagery Services from various sources DEM from LIDAR Lot Boundaries I want to ...
2
votes
2answers
31 views

Rasterize line shapefile

I'm trying to convert a line shapefile to a raster image at QGis, but my attempts have been unsuccessful. I've tried to use Raster/Conversion/Rasterize and SAGA/Grid - gridding/Shapes to grid, but to ...
2
votes
1answer
33 views

Using QGIS to access data delivered by ArcGIS for Server?

Can I use QGIS to access data delivered using ArcGIS Server? The following servers don't seem to be compatible with QGIS http://www.topofthesouthmaps.co.nz ...
0
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1answer
135 views

Select features from attribute table and then create a new field with the selected attribute data

I have a shape file which contains land use typology for my administrative area. I’m investigating deficiency in certain land uses and there are 2 ‘standards’ that we have to use. These standards use ...
2
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1answer
145 views

How to make labels' size relative to the map in QGIS1.8?

I want to make my labels' size changed automatically with the scale of the map,so in the menu of "Layer labeling settings",I set the Text size" in map Unit".However,the labels in the selected layer ...
1
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1answer
20 views

Clipping a TIGER Census Tract by Vector Outline

So I have recently downloaded the 2011 Tiger Census Tract for the 5 Boroughs of Manhattan which I would like to process for a future visualization. The Tract Shp file includes water areas, which I ...
2
votes
1answer
81 views

Calculate population coverage

I am relatively new to QGIS and hope I explain this right. I am looking at the percentage of an population that has geographical access to healthcare. Therefore I have one shapefile with village ...
1
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2answers
339 views

count lines in polygons

I found the following link to a post saying that a count lines in polygons had been added to ftools for QGIS: http://hub.qgis.org/issues/4712 However I can't find how to access this feature nor any ...