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

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4answers
1k views

Python Error Message with OpenLayer Plugin

I have just recently downloaded QGIS version 1.9.90-Alpha, Alpha, 5155176. I then went to install the OpenLayers plugin. That successfully downloaded and installed, or so I thought, but when I went ...
2
votes
4answers
633 views

Unable to load GRASS plugin

I upgraded from QGIS 1.7.0 to 1.8.0, including updating GRASS to version 6.4.3. Since then, GRASS isn't any longer listed in the Fetch Python plugins. I uninstalled and re-installed the whole package ...
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1answer
633 views

Using Landsat 8 for quantitative analysis - what DNs does GRASS require?

Hoping someone can short circuit a lot of exploration Landsat 8 values are stored as unint16 since the sensors work on a range 0 to 4096 whereas the L7+TM was 8 bit and had a digital number range 0 ...
2
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2answers
2k views

Exporting shapefile to PostGIS database in QGIS

How do I export a vector shapefile to PostGIS database? I am asking what format I have to export it.
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1answer
66 views

how to select parts of a shape in QGIS

I have to have a Shapefile of France of the bigger regions: Ile-de-France, Bretagne, etc. and that is already included in my shape. But its only shown the Arrondissements (smaller regions) in France ...
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2answers
103 views

Attribute Table Doubt in Qgis

I am having a shape file which consists of various fields for example: shape area ,shape length, locality, sub-locality,district etc.In my company they are demanding seprate shapefiles say for example ...
3
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0answers
183 views

Create a path following a road, interpolating from a set of points

I have several hundred vehicular routes within a city from which I wish to create shapefiles. These take the form of directions such as "From Green Street, turn left into Brown Street, Right into ...
2
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1answer
86 views

Revert back from RGBA raster to original 1 band raster cell value

I have a number or single band raster grids that have been converted to RGBA (png). I no longer have access to the orignal single band raster data but have the png files. Is there a way to convert the ...
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0answers
51 views

QGIS: georeferencing report: tail cutted off

I'm using QGIS 1.8.0-2 to georeference some old maps and want to report residuals and other information via the PDF report function of the Georeferencer tool. If there's too much information, it's cut ...
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1answer
49 views

How can I use a tif and a SID to make a basemap in QGIS?

I am trying to add a basemap in QGIS, projected correctly for PA. I have been directed to PASDA. When I click on the FTP download link, it gives me the option to download TIF data or SID data. What ...
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2answers
219 views

Customise the splash image of QGIS

Where can I find the splash image which is shown while starting QGIS, and how to customise it?
3
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2answers
417 views

How to do a Point to Polygon analysis with multiple variables?

I have a database of almost 10k crimes, which are divided in to 10 categories and plotted on a map I also have a database of 12k addresses, which are also plotted on the map. I aim to perform a ...
2
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1answer
166 views

QGIS: Colour GPS track by speed

sorry íf I might ask this question the 101 time, but I didn't found anything with google or SE. I have a CSV file with WGS84 trackpoints and visualizing them with QGIS textplugin works fine. The log ...
3
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1answer
413 views

Manipulating Azimuthal Equidistant Projections in QGIS

I have a shapefile of world countries that is projected as Azimuthal Equidistant with Chicago, USA as the center. I would like to change the projection such that Edinburgh, UK is the center. One would ...
2
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0answers
187 views

How to render a transparent raster layer on top of one or more vector layers with PyQgis?

I been trying to render a map with a 3 vector layers and one raster layer. The idea is that the raster layer should be on top of the other 3 vector layers. The problem is that even when I add the ...
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1answer
80 views

Why are some features missing from Raster menu in QGIS for linux?

I am running QGIS 1.8 in Ubuntu/Linux (13.04), with GDAL 1.10 installed. There seem to be features missing from GDAL tools that are present in Windows version. For example, I can't find Rasterize or ...
3
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1answer
251 views

Changing the CRS of a shapefile

Im trying to convert shapefile from one CRS to another in QGIS. On the layer menu, I right click on the shapefile, save it as with other name and there I change the CRS to the desired one (WGS 84). ...
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1answer
39 views

Why are color settings are not saved when exporting to a new file?

I extracted with QGIS a municipality from a state map, then divided it with a grid. I don't want the borders of the grid features to be seen so I changed the color of the map and the color of the ...
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4answers
259 views

Which UTM system do you recommend for Tamaulipas, Mexico?

I'm working with QGIS 1.8.0. Could anyone tell me which UTM system would be better to project a map of Mexico? There are too many to choose from. I have to convert my maps from WGS84 to UTM to do some ...
5
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2answers
615 views

How to calculate the number of cells with a given value?

I have a raster file where all cells have values between -3 and 7, no data value is -9999. Have can I calculate the number of cells with a specific value e.g. 6? Can I use the calculator?
4
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1answer
190 views

How can I accurately measure area of polygons using field calculator in qgis?

I have several polygon shapefiles, both set to WGS84 CRS. I have been using the google basemap with the Openlayers plugin, using the mercator CRS. On the fly CRS transformation is enabled. Should ...
0
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1answer
146 views

QGIS Extend Toolbar (GUI) Button Functionality via Python Plugin?

Is it possible to piggyback onto the QGIS split method via a python plugin? Are toolbar buttons accessible via the python API? This looks like the class that I need to access. Access ideas? ...
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1answer
152 views

Importing dxf as a vector layer or using dxf2shp function (Differences?)

I was trying to import a DXF file in QGIS. First tried using dxf2shp function but it didn´t work. I browse the dxf file and i put a name to the output and nothing was created in directory i chose. I ...
2
votes
1answer
420 views

Exporting geographic coordinates in QGis as projected (flat) coordinates

I've created some polygons with Google Earth which I'd like to convert to my flat map's coordinate system. I've loaded a few shapefiles into QGis of a county's roads, parcels, etc. The coordinate ...
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1answer
137 views

Why is there an offset between reprojection results of ArcGIS and QGIS from PSAD56 to WGS84?

I did a comparison of file system PSAD 56 to WGS 84 with arcgis and qgis and the difference is 8 m, why is the difference? This is a points file (shape) and it is in UTM Zone 19S.
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1answer
366 views

Creating contours with meaningful values from point data

I recently obtained a CSV containing the locations of all recorded bicycle accidents in Boston over the past few years. As an avid cyclist, I'd like to create a simple contour map that draws attention ...
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1answer
2k views

Import PDF to qgis

i have a PDF containing a region of Baltimore city that contains lots of polygons in it. you can download it from here: ...
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1answer
47 views

“merge” a raster data set on precipitation with a shapefile of administrative districts.

I'm currently using QGIS 1.8.0 I would like to "merge" a raster data set on precipitation with a shapefile of administrative districts. Basically my the aim is to figure out the precipitation in ...
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0answers
115 views

how can quantum be installed without administrative rights?

I have the impression from searching that this may have been possible with earlier versions but I don't know if it is possible with version 1.8. Thanks
0
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0answers
78 views

Mapping point data according to it respective value

The project I am trying to do is to map sum water quality (based on trace metals) data into QGIS. Each of the trace metals have their respective values and need to represent their concentration ...
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4answers
94 views

Add only unique features from another shapefile

I've got a problem that I am sure at least one of you have dealt with. I'm new to a company that makes use of a rather large database of point data. For whatever reason, the woman who was here before ...
2
votes
1answer
53 views

Divide map into features with invisible divisor lines

I'm working with QGIS 1.8.0. Is there a way to divide a map with a grid but make the divisor lines invisible? I have a shapefile as the one in the left and I want it to see as the one in the right but ...
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1answer
70 views

Conversion of coordinates of “Bochum coordinate system”

I need to convert historic coordinate data into more recent Gauß-Krueger data. Specifically, I need to convert "Bochum coordinates" used till 1960 in the local coal mines into DHDN/Gauß-Krüger zone 2 ...
2
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0answers
259 views

QGis Save Raster as Rendered Image

In QGIS 1.9.0 Master, when you right click on a raster in the Layers Panel and select "Save As", you can select the output mode to be "Raw Data" or "Renedered Image". When selecting the Rendered ...
5
votes
3answers
535 views

is there any way to run a GIS (Esri, Qgis or mapinfo) on a Windows8 RT tablet?

I am looking for a good idea to run a GIS program on a Dell XPS 10 with the Wind.8 RT.Thanks for any
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1answer
75 views

Counting and sum by two layers

I´ve got to layers, both polygons. Layer 1 consists of propertiers, where ID is individually names. Layer 2 consists of lakes. The query I want is: Total count of squaremeters of lakes for each ...
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0answers
108 views

How to convert a symbol style set for ArcGIS for use in QGIS?

Is there a way to convert a symbol style set for ArcGIS for use in QGIS? There are symbols used in Incident Command I would like to use in QGIS, but can only find a style set for use in ArcGIS. The ...
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0answers
37 views

Can I use the PyQgis QgisPluginLayer to create heatmaps?

I am working in an application to generate maps from a bunch of MIF/MID files, I already created almost all the maps that I need, but, now I want to create heatmaps. I can't find any way of creating ...
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3answers
289 views

Calculating MCP in QGIS

QGIS 1.8.0. Scipy installed. Statsmodels installed. Using Sextante to try to calculate MCP. When I run the MCP calculation from the Toolbox, a layer is added to the file, but the layer doesn't ...
0
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1answer
51 views

Using LANDFIRE data in QGIS

I am wanting to use the LANDFIRE rasters in QGIS, but I cannot get all the files to load. I load the w001001.adf file in the directory that contains the data, but I cannot access the attribute table, ...
2
votes
1answer
190 views

Adding UTM Zone Number to Coordinates

The computer program that I'm working with requires an 8 digit UTM Easting for the coordinates of shapefiles (i.e., the UTM zone number must be included with each coordinate within a shapefile). The ...
2
votes
2answers
296 views

Vehicle tracking by QGIS

I need to do routing for a vehicle. A map with detailed turn-by-turn driving directions should be generated. For example, it should be like car race game in which the map with vehicle tracking is ...
2
votes
0answers
132 views

Spatial Precision for Editing in Multiple GIS Clients

I have something I'd like to discuss, I'll try to explain it first, why it's important, and I'll explain how ArcGIS handles the issue, which I think is a good way to handle it. Finally I'd like to ...
1
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1answer
156 views

Bring trails onto a Garmin nuvi GPS

I seem to be having a lot of trouble uploading Utah Trails onto my nuvi 50 GPS. Is it not possible? The Black hills national forest has a img file that is able to be loaded onto the GPS, but the ...
3
votes
1answer
313 views

Invert Color Ramp in QGIS

This is a real basic question, but I can't seem to find it. How do I invert the color ramp in QGIS? I am using RdYlGn, but I would rather use GnYlRd. Seems really easy, but I can't seem to find ...
0
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1answer
167 views

Polygon grid shape file for landmass

I am interested in generating a polygon grid shape file for the landmass of the world. What I have presently is two tables in postgreSQL. Table 1: Coastal area shapefile ...
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0answers
53 views

How do I make vectorlayer with sql on PostGis via python code

I need to make a vectorLayer and fill with the SQL's results on PostGIS via python code. I'm working with python 2.7, QGIS 1.8 and PyQt 4.5 How do I it ? thanks
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0answers
37 views

QGIS adding points using decimal degrees [duplicate]

As duck blind permits are sold, we need to add the location using lat/long. we are working in ArcView now but would like to move to QGIS- Everything I was able to find seemed to deal with importing ...
4
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5answers
864 views

Display ESRI Shapefiles in a map in a browser. (Not in google maps)

I have a series of shapefiles that I need to render as a map on a webpage. I have an ASP.Net server, although I would prefer something that will work on Linux servers. I would like to find an easy to ...
2
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1answer
122 views

Can one expose variables to the Python console from a plugin in QGIS?

I have a QGIS plugin that performs a long-running operation, eventually producing and loading new shapefiles into QGIS. (I have this as a plugin rather than just a function that can be called from the ...