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

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2
votes
2answers
650 views

Misaligning shapefiles in QGIS, OpenLayers and ArcGIS Desktop?

I'm working with a set of shapefiles and have some problems with the "align" of them in QGIS when I load Openlayers to reference some points. OLs has an straight horizontal baseline but the shapefiles ...
0
votes
0answers
8 views

Visualizing variability in the size and shape of polygons [on hold]

I am working with a data set of area restrictions imposed by criminal courts. These restrictions ban a person form entering a demarcated area. These restrictions vary in their size, shape, and ...
3
votes
1answer
169 views

In QGis, why do parts of the OpenLayers layer export in a different scale and position?

I have a problem printing with google satellite maps in QGIS. In the composer it's all right, but in the pdf file some portions of the image are in a different scale and in a different position. An ...
0
votes
1answer
11 views

QGIS Export as PDF

I'm exporting a map to PDF in the print composer. See the map in the print composer As you can see, the top map is different from the bottom; the top has 10 tracts shaded in, the bottom has 6. Now ...
0
votes
0answers
6 views

Problem with values while reprojecting raster

I downloaded a series of Landsat 8 Images and I will be using QGIS to process them. The projection of 2 of them are incorrect, so I used "Warp tool" in QGIS to change them. The resulting rasters DO ...
0
votes
2answers
11 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 ...
2
votes
1answer
143 views

Python Error while installing Cartogram

I am quite new to GIS and qGIS especially. I would like to install cfarmers cartogram plugin. From what I understand, this has to be done manually - so I 've followed the instructions from ...
1
vote
0answers
13 views

LiDAR hillshade derivative

I have viewed a lidar terrain model hillshade .ovr file on QGIS and Arc and Arc has significantly higher resolution than QGIS. Any thoughts as to why this would happen and ways to enhance resolution ...
28
votes
4answers
7k views

How to generate Tiles with QGIS

Is it possible to generate map tiles from QGIS? I guess QGIS Server must have a way to do it, but is there a way to just generate the tiles and save them to disk? With the new symbology renderer and ...
5
votes
2answers
401 views

Creating contours for specific elevations

Input data: 1. an SRTM raster. 2. Point file of peaks. -Attributes contain ID, x, y, z and the elevation at which the peak is completely isolated from a neighboring peak. The output I want is a ...
0
votes
0answers
18 views

How to solve problem of non-ascii character on a zipfile on a plugin?

I'm making a plugin that needs extract files from a zipfile before processes them. For this I'm using zipfile lib. The ZIP file contains filenames with non-ascii chars. If I run this code on a "QGIS ...
1
vote
1answer
10 views

How do I import a NMEA file into QGIS 2.8?

I have some NMEA data recorded in a file - this is not a realtime application. How do I import that into QGIS 2.8?
2
votes
1answer
166 views

Import error when utilizing QGIS's Python Init function

Based on the answer to Referencing Qt UIs external to plugin with python. I'm trying to utilize the "Layer Properties / Fields / Python Init function" to execute a file (test_file.py) that is located ...
1
vote
0answers
29 views

Trouble Converting from a shp. to gpx file and up loading to GPS

Currently I have a series of random points within a shapefile that I would like to upload to my GPS. Every time I try to upload the points via "Save file" it come up with an error message (posted ...
3
votes
2answers
87 views

How to create multiple QGIS layers from multiple text files?

I have a few hundred txt files (each representing a line of a river bed profile) that I need to load as (point-) layers in QGIS. Partial example: 4504764.8331;5374251.3024;397.8871;2 ...
0
votes
0answers
8 views

QGIS, GDAL Georeferencer missing?

I've just installed QGIS 2.8 on the new Fedora 22 (64) that came out some days ago. Awkwardly, I can't find the GDAL Georeferencer that, to my knowledge, is supposed to come with every installation. ...
2
votes
1answer
138 views

How to deal with clipper error “cannot compute bounding box of cutline”?

I have merged about 20 OS tiles in to a single raster and I am trying to clip the merged tiles using a single polygon which itself was created from a small number of ward boundaries, merged using the ...
0
votes
1answer
29 views

OpenStreetMap (OSM) data is misregistered upon download, in just one area?

I have a satellite image over the area of Forez, France. I checked that the landmarks on the corner points coincide with the landmarks of Google Maps at the same coordinates, so the image is not ...
4
votes
1answer
89 views

QGIS equivalent to ArcGIS Aggregate Polygons?

I am looking for a tool in QGIS 2.40 that performs the function ArcGIS refers to as Aggregate Polygons. Basically it takes a group of polygons within a specified distance and creates a concave hull ...
0
votes
1answer
239 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 ...
0
votes
0answers
14 views

strange raster calculator behavior in QGIS

I used to work with qgis 2.8.1 in Lubuntu and in windows7. Each time I try to multiplicate a map for a number comprise between 0 and 1 (i.e. 0.1) I get a good results on windows OS, but I get a map ...
0
votes
0answers
12 views

QGIS Crashing on android Tab 3

I have installed QGIS on my Samsung Tab 3 Neo (SM-T111)(android 4.2.2) from Google Playstore.It Installed with Ministro Qit & library files. It is opening with QGIS 2.8 (Wien) Logo but closing ...
0
votes
0answers
35 views

How to process a big number of raster outputs with r.series?

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) ...
1
vote
0answers
22 views

Exporting QGIS styles to SLD for GeoServer?

I´m starting to dive into sld creation for Geoserver 2.7.1 Therefore I´ve also looked at Qgis 2.8.2 as it can export styles to SLD. Where I´m clueless is the big amount of used ...
1
vote
1answer
17 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
votes
5answers
128 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
votes
0answers
13 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
votes
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
votes
0answers
22 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
votes
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
votes
0answers
45 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
votes
0answers
15 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 ...
1
vote
1answer
15 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
votes
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 ...
7
votes
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
votes
1answer
43 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
votes
1answer
37 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
vote
1answer
24 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, ...
1
vote
1answer
40 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
vote
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 ...
1
vote
0answers
23 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
vote
1answer
154 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
votes
0answers
23 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
votes
0answers
16 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
vote
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 ...
1
vote
1answer
51 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
votes
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 ...
4
votes
2answers
54 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' ...
1
vote
1answer
105 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 ...
1
vote
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 ...