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

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9 views

QGIS assign multiple points data to closest polygon

I've got two layers: point layer polygon layer I need to add the points attributes to the polygon by location (if the point is on top of polygon add the atribute as a new field. I thought of ...
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1answer
15 views

How to use pre-generated Tiles

i have just created Tiles with Qtiles on Qgis, but how can put these folders (tile .png) on Geoserver or Mapserver? is it possible? I am trying to put the folder in C:\Program Files (x86)\GeoServer ...
2
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1answer
15 views

QGIS Heatmap plugin how to convert resulting raster values to meaningful values for legend

I am using QGIS and heatmap plugin and I need help with finding the meaning of the resulting raster values. I know there have been some questions, but none of them helped. This is my point layer input ...
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0answers
14 views

Spatial join with snapping

is there a tool in QGIS which is able to perform a spatial join with the possibility of define a snapping radius? For better understanding: I have 2 point shapes with attributes I need to join by ...
2
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0answers
15 views

What Does the Cell Value in a Composite Raster Mean?

When I make a composite raster in QGIS using the GRASS r.composite tool and then click on a certain cell I get these values in the blue/green/red/composite rasters: blue = 124 green = 124 red = 172 ...
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0answers
24 views

How can I find the center of the circle or ellipse I just created

I need to draw circles and ellipses with a certain length/width/ radius. I used the rectangles ovals digitizing plugin to create them, but only measured roughly the circles' radiuses. It would be ...
3
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2answers
58 views

Correctly merging DEM rasters and eliminating edge effects

I'm using 10m DEM rasters from the NRCS Data Gateway for a large portion of California. The problem is some strange tiling that appears after merging, but isn't present in the original data (before ...
0
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0answers
18 views

Can't find GPS in QGIS for Android

I have installed QGIS on my samsung galaxy note 10.1 (not 2014 edition) but I can't get contact with the GPS. I have the GPS information tool, but when I try to connect, QGIS shut down or nothing ...
2
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2answers
65 views

QGIS on Mac OS X 10.10 Yosemite

I just upgraded to OS X Yosemite therefore I have to use Java 8 (at least this is what Java tells me). After installing QGIS I was trying to start QGIS but I got the error message that I have to have ...
2
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2answers
30 views

Setting layer visibility in QGIS Python API

Im having a problem toggling the visibility of map layers in pyqgis (2.4). I have a simple interface, just the map canvas, no legend, and basically a radio button that toggles between two raster ...
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0answers
11 views

How to move to next feature by pressing right click

I have written the python code for adding vector layers,for getting and selection of features,for zooming. But my doubt is how can we write a python program where pressing the right click of mouse ...
0
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1answer
12 views

Enable ecw QGIS 2.4 on Linux Mint 16

I upgraded to Mint 16 and QGIS 2.4 and unable to get ecw to work following various guides available. Anyone willing to explain how to and why it is so hard. I run it on a windows machine out of the ...
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1answer
13 views

Interpolate dxf polyline vertex elevation from DTM?

I am working on several autocad polylines (with several vertices...) that have the exact N,E coords but now I would like to add the elevation data for every polyline's vertices from a dtm. I thought ...
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1answer
44 views

How to extract and save using QGIS?

I am new to QGIS and just downloaded QGIS 2.4 Chugiak. I am practicing QGIS by using training manual, as mentioned in above subject. I have questions in regard with the sentences in page 7: You ...
2
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2answers
27 views

Get cell size for raster in QGIS

How do you get the cell size of a raster in QGIS? This is a simple matter in Arc, just look at the properties. QGIS has properties, but no raster cell size. Thanks.
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1answer
20 views

Export background tile map to raster file

In QGIS I managed to display the ship traffic density from marinetraffic.com as a background tile map using the TileLayer plugin. Here is my TileLayer.tsv file: #title credit serviceUrl yOriginTop ...
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0answers
45 views

Generating Canal on DEM using ArcGIS for Desktop?

I want to generate a canal going from point A to B with a given slope. The canal should be on the underlying DEM. Is there any way to do this with the tools in ArcGIS 10 or do I have to do it ...
3
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2answers
38 views

Identify all continuous networks in a dataset

I have a set of pedestrian streets for a city. I would like to assign all of the streets that can be reached to one another along a continuous network to a unique group. I am wondering if there’s an ...
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0answers
19 views

Querying related tables in QGIS

I have a parcel layer and a table of property sales. I have the two tables related (it is a one-to-many relationship) in a QGIS project so that when you click on a parcel you see all the related ...
2
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1answer
27 views

QGIS syntax raster calculator

I'm working with QGIS and I want to reclassify a raster in different ranges. Using the following statement does not work even recognized as valid (2950 <= "dem_tallat @ 1"> = 3050) = 3000 ...
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0answers
24 views

Exported QGIS composer map using Openlayers base map has city labels shrunken

I've created a map in QGIS composer and I'm using the Google physical base map via the openlayers plugin. When working with the map in QGIS canvas & the composer view, I see city names with ...
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2answers
67 views

How to draw a polygon given a distance and bearing in QGIS

Apologies if this question has been asked before I'm not come across it. I want to draw a polygon given a length and a bearing, basically a square with lenght 1m. I cant seem to manage it with the ...
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1answer
34 views

Using QGIS and PostGIS for multi-user capabilities, similar to ArcSDE for ArcGIS [duplicate]

I have previously used ArcSDE technology with Microsoft SQL Server to allow for multi-user database editing. My ESRI licenses have recently ran out and I have been using QGIS for my GIS work. I am ...
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0answers
29 views

Guidelines for publishing large datasets on QGIS Web Client

Can anybody provide simple guidance to publishing large datasets on QGIS web client? I have a mixture of shapefiles and rasters to display. Biggest shapefile is 230 MB. Biggest raster is 1.4GB. At ...
3
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1answer
51 views

How to remove abnormalities from the Green vegetation fraction

Study area was clipped by using the shape file from Band 3 and Band 4. First, Band 3 and Band 4 were converted to at-satellite brightness temperature by using the built-in function in semi-automated ...
2
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2answers
39 views

QGIS 2.4.0 marker line interval does not work properly when line is bending

I am trying to style a line using marker line option. When I am using styling the line in the style window everything looks nice as you can see on the print screen bellow. I am using three line ...
3
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2answers
73 views

QGIS Installation on Windows

I'm newbie to QGIS and to this forum. I want to develop application using Qt on QGIS to real time updation/mapping of a symbol using GPS co-ordinates. Initially i have installed QGIS on Windows 32 ...
0
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1answer
20 views

osm2pgsql doesn't run in a QGis plugin

I have a problem with osm2pgsql when it runs in a qgis plugin. The function i use looks like this: osm2pgsql = "osm2pgsql -s -d {databaseName} -U {databaseUser} -H {databaseHost} -E ...
3
votes
1answer
35 views

matching shape file to csv within QGIS - all strings

I am trying to link a csv to a shape file using the method as described in this tutorial: http://maps.cga.harvard.edu/qgis/wkshop/join_csv.php It seems to work fine but the problem is that the csv ...
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0answers
17 views

Exporting QGIS Raster/Vector layers into one PDF? [duplicate]

I have seen a similiar post to this a while back (Is it possible to export GeoPDF from QGIS?), and thought I would try asking it again to see if there has been any improvement or new knowledge on ...
3
votes
3answers
82 views

Visualize overlapping line vertices in QGIS

I am trying to inspect the vertices of some linestrings in QGIS 2.4. My goal is to visualize every vertex of a line and easily find those that are duplicated. To clarify this, for an example line ...
3
votes
1answer
70 views

How do I merge DEM rasters correctly?

I've been struggling with this problem for awhile. Here is a curvature raster to illustrate the problem. I'm using 10m DEM rasters from the NRCS Data Gateway for a large portion of California. The ...
1
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1answer
20 views

QGIS: OSM Landscape layer not printed

I am new in GIS and I am trying to print a new map. If I use Google Street and web layer, it got printed without problem in the composer, but OSM Landscape does not appear on the printed document (it ...
3
votes
2answers
46 views

Locate points that are within a certain distance of other points in QGIS

I need a way of locating all points in my dataset that are within a certain distance of any other point. For example, in the following data set in which EASTING AND NORTHING are British National Grid ...
2
votes
1answer
30 views

View with sequence in QGIS 2.4

In postgres, I created a view with a sequence nextval() to have an unique id (called vid). I tried to vizualise this view in QGIS but it failed. It seems that nexval() causes some issue according to a ...
3
votes
1answer
58 views

Distincly color world map by language in QGIS 2.4

For a map of Wikipedia language prefixes, I need to color a map by a country's value in the 'language' column. I. e. all countries with the same language worldwide should share a color, which they ...
2
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0answers
29 views

How to calculate surface out of GPS points in QGIS

I have uploaded several squares (which consist out of 4 GPS points, not connected). I need the total surface of the squares. Is there a simple way of doing this? Do I create polygons and than ...
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0answers
36 views

How to load Google Satellite images in QGIS using python [on hold]

I have to write a python program to remove all the existing vector layers in QGIS. I then have to write a python program to load the Google satellite images. Please help me by answering this ...
0
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1answer
28 views

How to manage the CRS of Open-Layers plugin in QGIS?

I am working with OpenLayers plugin in QGIS 1.8 but I am not sure on how should I manage thc CRS. The defaul CRS for Googles/Bing layers is WGS84/Pseudo Mercator (EPGS:3857) but I am not sure on the ...
0
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1answer
27 views

How to run and debug PyQGIS scripts in PyCharm Community Edition 3.4.1

I am working with creating plugins for QGIS 2.4.0 (Chugiak). I am curious to know how I can write the codes, and debug them in the environment I am comfortable in, i.e. PyCharm Community Edition ...
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0answers
17 views

QGIS PointConnector Plugin - x out of x lines not drawn

Unfortunately every try to generate lines between points (.shp) with ids (1-6) and a csv-file with from - to values failed. Maybe you can give me a hint whats wrong with my workflow? 1) I generated a ...
0
votes
2answers
57 views

How to draw a perfect circle with a set radius in meters on map?

Following this istructions on how to draw a circle I can make buffer layer on each point I need. I am not able to draw perfects circle because the buffer will be elliptic? The CSR is EPSG:4326 - WGS ...
0
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0answers
27 views

Open a *.qgs project file in API, why maps do not show?

I'm using QGIS-2.4.0 API. I saved a test.qgs file in QGIS Desktop, in this project, there is one layer that is visible in it. Then I open the test.qgs project file in QGIS API to developing an App, ...
4
votes
1answer
62 views

Why are my calls to SAGA routines in QGIS not working cross platform?

The ability to write and run cross platform scripts for QGIS using python is OUTSTANDING! However, when I try to run the SAGA:MERGESHAPESLAYERS algorithm from a python script it works fine in windows ...
6
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0answers
87 views

How to produce high-resolution DEMs from new Sentinel-1 data?

This is a general question relating to the new Sentinel-1 data. I'm interested in the potential for using this data to create high resolution DEMs in GIS (I use QGIS), to investigate archaeological ...
2
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0answers
45 views

Issue with dissolving a polygons layer in QGIS 2.4

I downloaded a dataset of roads and parks from OSM. I then buffered the roads and merged with the parks. Now - all i want is to dissolve / union all the features in the merged layer. I fail to do it ...
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1answer
33 views

How to save multiple layers from QGIS to a Spatialite db?

I thought I had asked this before but I can't find any trace of it. Each time I save a layer from QGIS as a spatialite it insists on creating a new db ( if you select a existing db you are asked ...
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1answer
29 views

QGIS: How to get Symbols saved in GPX Files

I have some waypoint layers that contain different types of points and I distinguish these in QGIS by different symbols and colours. I want to export these to a GPX file that I can download to my GPS ...
2
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0answers
23 views

How to move to the next feature in the polygon with user keyboard inputs

I am new to this qgis i have one question. There is one rectangle and it is divided into some 20 grids.I wrote a program to zoom into the each feature.but if i am in one feature i want to move to the ...
1
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1answer
38 views

Open Source solution to batch process shortest distance between points along road networks?

I have the locations geocoded (a fairly small dataset, ~200), but I haven't found a straightforward way to load these data into QGIS and perform network analysis between nodes. Any suggestions? ...