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

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1answer
15 views

Transform from Lambert Azimuthal “old” to ETRS89_LAEA

I'm currently struggling to convert a small .asc dataset with no defined projection. The projection that has to be first applied is Lambert Azimuthal "old" projection: In PROJ.4 +proj=laea +lat_0=48 ...
0
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5answers
123 views

How to create 10m DEM from 30m DEM?

I am not regularly working in raster analysis. I have a 30M DEM and I would like to create a 10 DEM out of that. Is it possible to do this using QGIS? and How? I have got the following files ...
0
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0answers
9 views

Calculating Odd and Even side of road using PyQGIS and GRASS

I'm trying to programmatically and automatically assign odd and even sides of a road to number homes using QGIS and GRASS. I noticed this other post, which gives a solution using PostGIS and I have ...
3
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2answers
1k views

Can I fix 'qodbc3:unable to execute statement' when querying SQL Server 2008?

I was testing features of QGIS and its really cool.I tried to query each table using right click and query but I can't query sql server 2008 database : Error: An error occured when executing the ...
2
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0answers
15 views

Interpreting results of QGIS intepolation and Heat map from point shapefile

I have taken a step interpolation and heat map of the data point shapefile (building Centroid) with QGIS ver-2.8.1, as shown below. My question are: What is the difference of the two methods? How ...
2
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3answers
3k views

How to open an ArcGIS Desktop .lpk file using QGIS on a Mac?

I downloaded an LPK file from the ESRI site that contains USPS defined zip codes. Because I'm working with QGIS on a Mac, I converted the file to a .zip. There's a .lyr file that opened up in the zip, ...
0
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0answers
29 views

How to convert X and Y coordinates to longitude and latitude?

I have looked at every single one of the answers about this question and none of them seem to work. I have downloaded a shapefile with points that represent specific buildings into QGIS. I would like ...
0
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0answers
6 views

How to use a PostGIS sequence in QGIS editing session?

I can't seem to get the sequence on my PostGIS table to increment to NEXTVAL in a QGIS editing session. My PostGIS table is defined as: CREATE TABLE qgis_topology_editing_test ( geom ...
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1answer
8 views

Not all polygons removed when cutting from vector layer in QGIS

I have created ten polygons representing lakes on a vector layer, and I am trying to cut them from an imported and re-projected vector layer of administrative districts. When I use the 'Cut with ...
0
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1answer
42 views

C# GIS Bing Maps

I'm developing an application in C# and I want to show my data on map like Bing maps, so what is the best the best way to do that. I have seen SharpMap but I could not load Bing map to it. please ...
0
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1answer
9 views

Join attributes by location doesn’t appear to be including data that it should

I am trying to calculate the number of bus stops which are within 400m of c. 100 properties that are in relatively close proximity to one another. Using MMQIS I created the 400m buffer for the ...
7
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2answers
1k views

Is there any 'Auto-complete polygon' tool in QGIS?

Is there any 'Auto-complete polygon' tool in QGIS, similar to the one existing in ArcGIS?
2
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1answer
39 views

Is there a way to have spaces in QGIS leaflet web map layer names?

When I export a QGIS project to a leaflet webmap using QGIS2Leaf, is there a way I can have my layer names display with spaces. So for example in the image I would like OffshoreSACS to display as ...
0
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1answer
35 views

Vector to Raster using GDAL (gdal.RasterizeLayer) : Error in Output Raster(generating output raster with NAN values)

For rasterizing a vector layer, I have tried gdal.RasterizeLayer method for converting vector(shapefile) to raster(tiff). But its giving raster output with NAN values(complete black image). I need ...
1
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1answer
23 views

why the values are NULL if I join the csv table to a point shp file [on hold]

So my problem is all values are NULL if I join my csv-table to a point-shape-file. (QGIS) Why? I tried so much thing but I can not find and handle the problem. I have customer names in the csv, ...
0
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1answer
37 views

delete a space with the field caculator

I would like to delete the space in this number like this 'F00 089' with the field-calculator. Is theres a function in the field-calculator? ! see my screenshot
1
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1answer
148 views

Trying to set NAD 1983 EPSG 102631 in QGIS

I was able to find the right coordinate system online NAD 1983 Alaska But now I don't know what to do. I can't find the coordinate system on QGIS. When I choose the one I think is correct it warps ...
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0answers
18 views

Spread overlapping points with similar but not identical coordinates

I've been looking for a solution for my problem for quite a while, but never found the answer.I have a lot of data point which are very close to each other, a lot of them have the same coordinates. ...
1
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1answer
152 views

How to recover deleted data from an edited point layer?

As a newbie in GIS, I didn't fail to make a newbie mistake. While editing a point layer I accidentaly deleted all the introduced data. I duplicated a layer, as it was more convenient (same style and ...
0
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0answers
21 views

Least cost path analysis : a lot of sources and destinations

I'm working on a 15*10 km area, splatted in a 50*50 m cell grid. I want to compute the time needed to travel from a single starting point to each cell centroid, combining driving and walking time. I ...
0
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0answers
12 views

Display graduated QGIS buggy?

I counted points in polygons in PostGIS like this UPDATE hexagons SET count = (SELECT count(*) FROM points WHERE ST_Within(points.geom, hexagons.geom)); That came back with that UPDATE 1554 That ...
1
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1answer
27 views

How do I add packages to Standalone Qgis's Python?

I have installed the QGIS 2.8 on my Windows 8.1 system, using the Standalone Installer. I now wish to install the VectorBender plugin. The docs for this plugin say, that I need to install matplotlib ...
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1answer
46 views

“Get” results of PostGIS [on hold]

I am getting warm with post PostGIS. I am working in the Command Line. What I am wondering is how do I "get" the results of PostGIS. So imagine I have this select name, neighname from neighborhoods ...
3
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1answer
160 views

How to map flood areas from a set of points containing surface and height of water?

I am working on the damages made by the typhoon Haiyan. I use QGIS 2.0 with extensions and toolbox, and MapInfo. I have vectors, rasters of the place. I want to map the flood area along the ...
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0answers
12 views

Need help for a Field Calculator function in PyQGIS

I need help for a program I'm trying to use in QGIS. Let me explain: I have two files: A polygon shapefile that comes from a DXF file A dbf with information As you can imagine, dbf file has ...
3
votes
2answers
52 views

How can I use boolean value in QGIS style rule?

I'm trying to make a style based on rules, and I want to use a boolean field I have created for that. But I do the following: "field" like 'TRUE' "field" like TRUE "field" like 1 "field" like '1' ...
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1answer
104 views

Cannot produce pie chart in QGIS 2.2

I have a shapefile to which I joined two tables from a MySql database. I used one column of the first table to color the polygons in my shapefile which works fine. Three columns out of the second ...
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0answers
18 views

QGIS shuts down when I try to open a “.sos” file

I am trying to open a ".sos" file in QGIS. I have QGIS installed using OSGeo4W and added the gdal-sosi package. This should do the trick. But QGIS just shuts down when I try to open the file. It ...
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0answers
24 views

How to ceate new vector layers / save output in QGIS scripting?

I need to create a script in QGIS which stores outputs. In this case, official documentation didn't help to me. When I use geoprocessing (processing.runalg()) for vector layers. In some cases, output ...
3
votes
1answer
53 views

How to center continuous raster layer by subtracting mean and dividing by standard deviation using QGIS raster calculator?

I'm trying to extrapolate a spatial model to a map in QGIS using the raster calculator. The model predicts the value of a pixel given the environmental conditions at this location (e.g. elevation, ...
1
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2answers
33 views

Changing style in ModelBuilder?

Is it possible to have the output features of a model have a specific visual style? The features come out in a random assortment of colors and very small. Is there a tool for this? or any suggestions? ...
0
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1answer
15 views

Exporting KML from QGIS with relation (one-to-many) table as popup

Here is a challenging one for someone. I have two tables in QGIS. Holes (parent) - Which contains the borehole locations. Strata (child) - which has many rows that contain the strata for each ...
0
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0answers
18 views

Preprocessing GeoEye-1 in GRASS iatcorr

I am trying to do a study on land use change using three high-res images of an area from three sources (Quickbird, GeoEye-1, WV-3). I have managed to calibrate the Quickbird data using QGIS raster ...
2
votes
0answers
17 views

QGIS 2.8 Plugin Icon not Showing in the plugin information pane

I created a QGIS plugin with Plugin Builder. Even though the icon set in the metadata.txt is displayed in the Plugin Manager list (left to the plugin name in the installed plugin list), it is not ...
0
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0answers
12 views

Negative reflectance values from raster calculator computation of GeoEye-1 image

I tried to convert DN values of a pansharpened 2010 GeoEye-1 image into radiance then reflectance in QGIS using raster calculator with the following formulas: (1) L= gain* DN + bias; (2) p = pi* L* ...
0
votes
1answer
20 views

How to update raster color ramp with new min/max values using PyQGIS?

I'm trying to update a single band psuedo color renderer with new min/max values from the python console. All the code samples i have been able to find deal with constructing a renderer from scratch, ...
5
votes
3answers
3k views

How to style points in QGIS based on multiple attributes

While trying to find a useful way having earthquakes displayed, I noticed that it isn't that easy to manage. I'd like to be able to recognize the "Magnitude", "Date", and "Depth" from the style of ...
8
votes
3answers
14k views

How to export Polygons to CSV with coordinates?

I am very new to QGIS, so please bear with me. I have a ".shp" file, which is contains a set of boundaries for suburbs of Australia. I opened it to QGIS and I would like to export it into a CSV file ...
1
vote
1answer
16 views

How to create a rule-based gradient using an expression

I am mapping points with values from 0-100 and want to display these using a gradient color scheme. However I also want to specify the breaks as regular intervals along this range. For a gradient QGIS ...
2
votes
4answers
43 views

How to create different size of bubbles with different colors? [duplicate]

I have a set of points with fields like 'TYPE','SIZE','SALES VOLUME',what i would like to do in QGIS is: Apply different color code by 'TYPE', Apply graduated size of bubble circles based on 'SIZE' ...
1
vote
1answer
25 views

Pulling a cvs file from a website into QGIS with the ability to automatically refresh.

I am attempting to pull a cvs file from a website that is updated daily. I would like to have a process that can automatically perform the process and save daily as a new layer. The cvs file is ...
4
votes
1answer
153 views

Pulling CSV file directly from website into QGIS?

I want to be able to automatically update my csv files in a QGIS project. My organization has an online database that can easily export csv files. These csv files are constantly updated with new ...
0
votes
0answers
7 views

Add save/commit button to custom feature from

I would like to add a save/commit button to a custom QGIS feature from. This is very helpful when there is a linked table dispayed on the same form - the link will work only once the main table has ...
0
votes
0answers
19 views

How to fill holes/missing values in XYZ data / a DEM with QGIS?

I have equidistant XYZ point (text) data that I used to create a point grid. However, it's not perfect - there are some holes. I then created a DSM raster from it, which obviously has the holes too. ...
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0answers
69 views

QGIS web client - ERROR generating pdf

If I push the print Button at the toolbar, i will get the menu which works fine. But then i want to print the map the pdf doesn't generate. That's why i look into firebug and i get following ...
1
vote
1answer
27 views

Can I mimic the “open” action in QGIS with python and manipulate the field content used for the action?

I am using QGIS actions (type: "open") to link ECM searches to objects on the map. The basic syntax is very simple: protocol://searchterm1=[%"field1"%]&searchterm2=[%"field2"%] However, some ...
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0answers
16 views

Showing the composition in QGIS [on hold]

I´m currently using QGIS 2.8.1 and have create a plugin with the pluginbuilder. I´m trying to create a composed layout and want to show the layoutcomposer to the user at the end. I´ve done the ...
0
votes
3answers
10k views

How to publish my map on the web? [closed]

I want to publish my map is created in QGIS 1.7.4 version on to the web.Can u pls suggest me how to publish the map with proper documentaion and screen shots if possible?
0
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0answers
23 views

How to process a big number of raster outputs?

I am new to python and QGIS. I'm trying to take some simple operations (e.g. count, average) over a big number of raster maps from a python script. I'm using the "r.series" algorithm (from processing) ...
2
votes
2answers
26 views

How to link polygon features in one layer to polygon features in another, using largest overlap in QGIS or GRASS [duplicate]

I have two polygon layers: the first one contains small land lots (green in the image), the second one contains large zones (the purple line in the image attached separates 2 such zones). I want to ...