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

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2answers
224 views

QGIS: labelling with empty cells of attribute table [duplicate]

I'd like to label points in a vector layer. In my attribute table I have a .csv with a list of material for each position (it's the planning of marathon race). Some of the cells are empty, though ...
2
votes
1answer
304 views

QGIS, Is there a way to import 400 SVG files to the symbol list all in one go?

I need to import 400 SVG as SVG Markers to the QGIS styles library. I know how to do it one by one but I need a way to import all of them in one go... Is there a way? I am in QGIS 2.8.2. Wien.
1
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1answer
163 views

How to find the coordinates of the lowest point in a polygon

I am working in QGIS 2.6. I have a file of several polygons and I want for each one, to find the lowest point (where is it located and its elevation). I am using "Grid statistics for polygons" which ...
0
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1answer
63 views

joining non-spatial pollution model (csv file) to Qgis

I need help..I have csv file with concentration data but without coordinates. Start of pollution concentration connect with that one point on map. Is there any chance ? Start of pollution ...
0
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0answers
70 views

Find lines that have specific distance between them in QGIS

I have a rather large dataset that contains duplicated lines with an offset of 1m-5m and I want to find an efficient way to solve this problem using QGIS. Is there anyway in QGIS to find the lines ...
3
votes
1answer
197 views

Is the QGIS “Random selection within subset” selecting spatially random or randomly from the attribute table?

I am trying to figure out exactly what is being randomly selected. I have a layer of road segments and I would like it to select a road segment at random within a neighborhood (the subset). This would ...
1
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1answer
147 views

GRASS Zero-Crossing Edge Detection

I have a classification of vegetation communities across a landscape in a .tif format. I wanted to use the GRASS Zero-Crossing Edge Detection tool in QGIS to help define boundaries between my classes-...
2
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0answers
207 views

QGIS Server - GetPrint Request with SELECTION parameter

According to informations from this site I can use "SELECTION parameter" with GetPrint Request. I tried to achieve this but without success. With GetMap request everything is ok. Can some one help me ...
1
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1answer
87 views

Information of particular locations (points) in a map

For a marathon race I need to create a map with specific information about material needed in particular positions (eg crossroads). It's about 150 positions. You see one part in the picture below. ...
2
votes
1answer
1k views

QGIS Processing Toolbox disappeared [duplicate]

Suddenly the button for opening the toolbox is gone. I have searched really long already. Do you have any idea how to get it back?
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1answer
36 views

QGis Lines around points

Im my QGis project there are points representing oil wells and sysmic 2D lines. I'd like to know how many lines are there 1 Km around each well, for example.
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0answers
27 views

QGIS android issues with editing points on lines and polygons

I am using QGIS on an android tablet and cannot delete mistaken points in a line or polygon. Does anyone know how to do this? I also have an issue with the first point of a line/polygons starting not ...
1
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2answers
196 views

Rotating view without losing labels in QGIS?

Using QGIS 2.8 Wien and a beautiful shapefile from OpenStreetMap. When I rotate the map (either in the print composer or in the main QGIS panel) the labels with the street name disappear. I've tried ...
0
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1answer
97 views

Georeference a polyygon within a pdf file [duplicate]

I have this pdf file that contains a specific borough of my city, Montreal, with a polygon inside it. Link to pdf file: PDF FILE The jpeg image once exported from the pdf file is the following I ...
1
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0answers
101 views

Extract a specific vertex

I am trying to create catchments/watersheds for each line segment in my stream network. I've managed to get the coordinates for all of the end nodes of the line segments to use as pour points. However ...
1
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2answers
146 views

Why can't I load a .shp file with the Python Console in QGIS?

I'm trying to load a shape file into QGIS using iface.addVectorLayer, but whenever I do this, I get an error message "Layer is not valid: etc ..." However, if I try to load the same .shp file use the ...
1
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0answers
171 views

use qgis api in qtcreator

i have a college project that searches content in map. I did all instruction written in this site: http://kartoza.com/how-to-build-and-debug-qgis-with-qtcreator then built my sample project. this is ...
1
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1answer
180 views

ST_Intersection for polygons

I'm looking for a query that returns overlapping areas of two tables with polygon geometries. Using row_number() over() the entries of the gid column are not unique in the case of dumped multipolygons....
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0answers
46 views

QGIS / Python differences in result

I am working on a script that automatically calculates something for me. To be sure, I checked the result of the calculation with QGIS. Here are the statistics: STATISTICS PYTHON-CODE: MAXIMUM = 0....
1
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1answer
223 views

How to use subprocess module to run QGIS toolbox modules

I've been trying to use subprocess for a while now, but can't get it to work when calling QGIS modules. Here's my script: import subprocess call("processing.runalg('gdalogr:merge', [rasterin1,...
0
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1answer
75 views

Is it possible to join two different data sets in QGIS?

I have one data set which contains all federal states of Germany. The other dataset is about the population density in every km² in the EU. My goal is now to join these two Datasets so I can answer ...
1
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0answers
204 views

Training Manual 2.8 and exercise data differences

I am a new user and trying to teach myself about QGIS using the 2.8 Training Manual and the training_manual_exercise_data downloaded from QGIS. I am using the PDF of the manual, which seems to be ...
1
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1answer
59 views

Grass r.out.gdal, wrong values when importing to QGis

I have a problem with export/import functionalities between Grass and QGis. I create a raster file in Grass (with r.wind.sun, but that most likely does not matter) It has the following properties: ...
2
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1answer
59 views

How to create a raster of equidistant points with distance in meters using QGIS?

I need a set of equidistant points (like a raster) each in a 1km distance to the next over a certain area, in my case Germany. I know the feature "regular points" in QGIS where I can do just that but ...
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0answers
30 views

How to best import a US Map Schematic?

I would like to use the following wiki US Map schematic as a background to my map work. (http://en.wikipedia.org/wiki/File:Blank_US_Map.svg) It is a .svg file, and GeoReferencer is unable to import it....
2
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0answers
36 views

Is there a way to make the controls on QGIS android larger?

Is there a way to make the controls on QGIS android larger? e.g. When typing text into a field in the table view it is currently very small. I also have a issue/bug where the panels (layers, gps ...
3
votes
1answer
397 views

How to interpolate raster to get finer resolution?

I am working with precipitation raster layer. It happens the raster data to be in a resolution of 0.25 degrees grid. How could I interpolate those pixels to have a better resolution, say, a resolution ...
3
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0answers
100 views

Visualizing variability in the size and shape of polygons

I am working with a data set of area restrictions imposed by criminal courts. These restrictions ban a person from entering a demarcated area. These restrictions vary in their size, shape, and ...
0
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2answers
118 views

Why is the vector style in the PDF export different than in print composer? [closed]

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 ...
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0answers
69 views

What can I do to reproject rasters without modifying the original values?

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 ...
2
votes
1answer
171 views

Why does my hillshade .ovr display in lower resolution in QGIS?

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 ...
1
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1answer
384 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
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1answer
224 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 ...
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0answers
115 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. ...
1
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0answers
84 views

QGIS Crashing on android 4.2.2 Tablet

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 ...
1
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1answer
46 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 ...
3
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0answers
2k 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 prefixes/namespaces....
3
votes
1answer
121 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 ...
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0answers
122 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 geometry(...
0
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0answers
327 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 ...
1
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1answer
36 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 ...
2
votes
0answers
77 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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3answers
68 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 ...
1
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1answer
96 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
0
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0answers
31 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
154 views

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

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, ...
2
votes
1answer
304 views

How to open a “.sos” file without crashing QGIS?

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 ...
0
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0answers
247 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
2answers
174 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 ...
1
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1answer
61 views

“Get” results of PostGIS [closed]

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 ...