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

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3
votes
1answer
191 views

Batch map creation, iterated over attributes of a layer, in QGIS

I am using QGIS 2.0.1 under Mac OS-X 10.8.2. I have a layer of counties in New Mexico to which I have joined a csv file that includes presence / absence of plant species by county. I've set up the ...
2
votes
1answer
99 views

Add Custom Data to OpenLayers Plugin for QGIS

Is there a way to add custom data to the OpenLayers plugin for QGIS? I have tiled data using Map Tiler, which has produced my zoom levels, and an OpenLayers.html. I am hosting it internally on our ...
1
vote
0answers
82 views

Rendering OSM with QGIS for MapServer to use in OpenLayers

I want to show tiles in OpenLayers offline. I've installed QGIS 2.0, TileCache, and MapServer on Windows. Enabled plugin OpenLayers in QGIS. What kind of data I suppose to extract from QGIS with my ...
1
vote
0answers
65 views

header information is missing from image, after writing using opencv

I am doing complement of an image using open-cv python, while writing the image, open-cv is not writing the header information in the complemented image. my image data are in TIFF format. i am doing ...
-2
votes
2answers
199 views

How can I read binary PBF and bzipped XML OSM data in QGIS?

How can I read binary PBF OSM data, e.g. example.osm.pbf or bzipped XML OSM data in QGIS?
2
votes
3answers
206 views

How do I get the value of the pixel under the cursor?

Is there a tool or something that will give me the value of the pixel under the cursor? What I've got in mind in something like the eyedropper tool in graphics programs that allows you to ...
0
votes
0answers
63 views

How to crop google hybrid map in QGIS? [duplicate]

I download google map from openlayers plugin in QGIS, it was like this: How can I crop the view to get a certain area from the map like this:
2
votes
1answer
171 views

How can I add grid lines to a print composition using pyqgis?

I'm writing a qgis plugin to create an image in the print composer of the current map. I can get the map rendered in the proper place with a frame of the right width, and I can get grid annotations ...
1
vote
0answers
52 views

How to convert overlapping polygons in single layer to raster by count in QGIS?

I'm trying to do this in QGIS 2.0 (Mac Mt Lion). But cannot do step 2, as I can't dissolve original polygons by 'count' in QGIS (in that tool at least). Advice?
1
vote
0answers
50 views

QGIS over WatchGuard Mobile VPN with SSL

something quite strange occured today. I connected to my office through WatchGuard Mobile VPN with SSL enabled. I got loads of errors about SSL certificates, WMS errors (there were WMS layers in the ...
0
votes
1answer
377 views

How can I download maps from mapquest?

I need to get a detailed map for my own purposes. I need it detailed as much as I can see the buildings (like google map hybrid mode). I went to http://open.mapquest.com/ but I couldn't find the way ...
0
votes
1answer
209 views

Flow mapper plugin failed

I want to create a desire line with the Flow Mapper plugin using QGIS version 2.1. After I did, it has failed. The data that I used is pictured below. There may be an error procedure I have used. Can ...
0
votes
0answers
76 views

QGIS: Albers projection in lat lng?

I'm trying to make a map of Russia in the Albers projection. My projection string is: +proj=aea +lat_1=45 +lat_2=70 +lat_0=40 +lon_0=100 +x_0=20 +y_0=20 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m ...
0
votes
0answers
81 views

Cropping elements from one layer to an element from another

I'm trying to make a hex map of a country (Russia, in this case). To do this, I've opened a map of Russia in QGIS (from Natural Earth), set up my projection, and created a hex grid with MMQGIS. So ...
1
vote
3answers
235 views

How to access shapefile table in QGIS Modeler R scripts?

I need to develop .rsx scripts for QGIS 2.0.1 Modeler to do statistical elaborations on data tables of loaded vector layers. In this case I am not interested in accessing shapefile geometries, I'd ...
1
vote
1answer
120 views

OS Boundary Line shp export CSV with description and lat/lng

I have found several post saying it is possible in QGIS to export OS Boundary Line shp files to csv's containing the boundary line in lat/lng (for use on Google map) along with the name of the area, ...
1
vote
0answers
185 views

QGIS 2.0 Problem with loading a Layer Style file that contains a transparent pixel list

I work with QGIS 2.0.1. For my raster file I have created a Layer Style with a transparent pixel list. When I import a rasterfile in a new project and load the layer-style file, the map changed to ...
1
vote
0answers
180 views

QGIS print composer error due to Java script problem!

I've been experiencing a problem with the QGIS print composer. I am working on a Linux Ubuntu platform (Release 12.04 (precise) 64-bit) and I am using QGIS 2.0.1 Dufour. I need to export a number of ...
1
vote
1answer
61 views

How to measure and mark a line or point as a template QGIS?

I'm digitizing some of our sewer assets and need to be able to measure distance and create points. So, for instance, I have a sewer main that is 65m long. I need to mark a point at the 32m mark, then ...
1
vote
0answers
76 views

QGIS grabs incorrect field values for categorized style classification

as seen in the first image, the field values QGIS returns when I attempt a 'select by expression' are values found nowhere in the field in question ('FLD_ZONE'). Instead, it returns a selection of ...
0
votes
2answers
104 views

How can you insert a custom symbol?

How can you use a custom symbol for either dot density or proportional symbol maps in QGIS? Is there a way to import a symbol of your own such as a drawing or image that you can create or download ...
0
votes
1answer
85 views

How to change QGIS project color space

Is it possible to change the color model of an entire QGIS project from RGB to CYMK? I know that it's possible to change the color models of individual symbols/features (through the style manager), ...
0
votes
1answer
50 views

QGIS Raster Calculator dialog doesn't resemble that in documentation

I'm very new to QGIS. Raster Calculator looks (from online sources) like it ought to have all kinds of buttons and fields. Mine is rather stripped down. I have two rasters open, and I just want to ...
1
vote
2answers
438 views

How to avoid “Handle bad layers” message when using QGIS Flowmapper plugin?

In QGIS, if I close a project and try to open it a few days later I often get a message that says "Handle bad layers". This is very frustrating because when I open the project various layers will have ...
0
votes
1answer
107 views

How to change the size of Hex bins?

I am creating a map in QGIS and I am using a hex bin layer. To create this layer I used the MMQGIS plugin and created a grid layer. However, the size of my hexagons that I created are too small, and I ...
1
vote
1answer
385 views

Microsoft Access mdb “is not a valid or recognized data source” in QGIS

The answer to RyanDalton's question "Can QGIS read an ODBC connection?" explains how to establish a link in QGIS with an MS-Access table. Following his steps, I can establish an ODBC link (I ...
4
votes
2answers
352 views

Merge two rasters with no data value

I have two rasters: Raster A and B. Raster A has has only values of 0. The white area in Raster B are No Data values. I want to merge them to one raster (Raster C). So basically I want all pixels in ...
2
votes
0answers
181 views

How to compile QGIS with Oracle Spatial support for Linux?

I compiled it on Fedora and Ubuntu, but got error "Cannot get Oracle select dialog from provider." while trying to add Oracle layer. Packages in repositories don`t have oracle spatial support. Can ...
3
votes
2answers
76 views

Saving edits slowing down (QGIS 2.01)

QGIS 2.01 on Windows 8 I have a polygon layer which I edit in QGIS 2.01. Editing (cutting, deleting, editing new polygons with attributes) works fine. I am saving the changes after every edit or so ...
0
votes
0answers
124 views

changing unit of area from unknown unit to square meters

I am using Qgis 1.8 and I have this polygon.Now I wanted to know the area of this polygon and i have used field calculator and it shows my area as 651692439.under general tab crs is : EPSG:4326 - WGS ...
0
votes
2answers
1k views

Make a polygon from intersecting lines in QGIS, using Polygonize or similar?

In QGIS, I want to make polygons from a set of intersecting lines. Looking at the screenshot here, I want chop the purple line (it's a closed line, not a polygon) where it crosses the green and blue ...
2
votes
2answers
103 views

How can I get repeated vector grid in horizontal direction?

I need to get repeated vector grid layer in horizontally direction. I created many polygon vector grid layers, and their extents as listed bellow (Xmin-Ymin, Xmax-Ymax): Layer 1: 5910000 3040000 ...
2
votes
1answer
97 views

Obtain Longitude/Latitude Values and Export Data From QGIS

I have a CSV file with address data elements (Street# and Name, City, State, Zip). I'd like to be able obtain corresponding X,Y coordinate for each of the address? How do I achieve this using QGIS? ...
7
votes
2answers
569 views

How to split lines into equal segments with QGIS?

I'm attempting to split a curved (wiggle) line into equal length segments. Have used Grass's v.split which works to a degree but does not provide the output I'm after. v.split will extract segmented ...
1
vote
1answer
158 views

How can I style many layers of vector grid once in QGIS?

After I created many of vector grid layers, I now need to style them in a batch system. Is there any way to do this? If that is not possible, how can I use the layer duplicate option to inherit the ...
1
vote
2answers
71 views

How can I change vector grid extents in QGIS?

I created many vector grids, but later I discovered that I need to modify some of their extents, hence, How can I change vector grid's extents (xmin, xmax, ymin and ymax) in QGIS?
1
vote
2answers
46 views

Editting Attribute properties in QGIS

I am trying to edit the precision of my area attribute in QGIS 2.0. It is currently at 0 but I want to change it to 3. I have not been able to find the answer to this anywhere. Is there a way to edit ...
0
votes
1answer
309 views

Flow Mapping Lines by Magnitude

I am attempting to map the flow of remittances into Japan using the FlowMapper plugin in QGIS. When I use the Style--> Advanced--> Size Scale field--> magnitude command, the lines become so thick ...
1
vote
2answers
649 views

How to interpolate a point vector layer inside a boundary (polygon layer) QGIS/GRASS/SAGA?

I have a to create a heatmap of water temperatures inside a lake for which I have sample points. The map should look much like the climate maps generated by climate change models. I have the ...
0
votes
1answer
235 views

How can i clip vector layer in qgis and python?

I want to write a python function to create a shape file layer from clipping an input layer using a mask. Does someone know the way how to do it?
0
votes
1answer
30 views

Can't generate leaders with EasyCustomLabeling

I'm using EasyCustomLabeling with QGIS 2.0.1 and can't get it to generate the leader lines it is supposed to in Action 2. I create a new layer with EasyCustomLabeling, move labels to new locations, ...
1
vote
1answer
62 views

How to hide grid's labels when zooming out?

I have used polygon grid layer on my map, and I used to label the layer with ID automatically, and the result was convenient for me: But when I zoomed out, the labels didn't hide at all! and they ...
2
votes
0answers
216 views

How to add an offset to a GeoJSON layer in Leaflet?

Using the example GeoJSON tutorial code at leafletjs.com. Change the myLines variable so that the two lines overlap, but run in opposite directions as follows: var myLines = [{ "type": ...
3
votes
2answers
580 views

How do I define a bounding box within a WFS-request?

I need to get some data from via a WFS connection but due to the sheer size of the data, it takes for ever to load into Qgis or MapInfo. MapInfo has a feature which allows you to restrict the wfs ...
1
vote
1answer
122 views

no output file with grass:r.los

i'm using qgis 2.0 and i want to calculate a viewshed using r.los from grass tool box. after typing in the python console and a few seconds, i don't get an error message, but there is no file. the ...
0
votes
2answers
40 views

Fast location of items via attribute table in QGIS

Is there a way to quickly go straight to an item via the attribute table in QGIS 2.0.1? E.g similar to in ArcMap when you have the table open and double click the record and it zooms to it? I have a ...
2
votes
0answers
15 views

Eliminating/minimizing distortion in 200 NM EEZ buffers [duplicate]

I frequently need to calculate buffers of 200 nautical miles from country or baseline polygons in order to map maritime Exclusive Economic Zones (EEZs). However, I've noticed that when generating the ...
0
votes
0answers
31 views

Problems with other applications after installing QGIS 2.0.1

Since the official QGIS installation 2.0.1 (Virtual Server) various core applications from other departments in the municipality do not work always properly. Does anyone know the problem? Thank you ...
0
votes
0answers
32 views

Viewer Function

Is there a Viewer function/display in QGis as it is in ArcGIS. Or is there an other possibility to limit the access (just visualisation, no analysis). Thank you for your answer.
3
votes
3answers
480 views

Is there a way to hillshade vector polygons with a DEM in QGIS?

I have a layer of cadastral polygons that I'd like to display as hillshaded. For the elevation model I can use either an SRTM geotiff or use a set of 20m contour vectors. While I could make a jpeg ...