Tagged Questions

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

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1
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1answer
275 views

How to use QgsOverlayAnalyzer class in pyQGIS?

I am very new to Python scripting in QuantumGIS, so bear with me please. I am trying to use the QgsOverlayAnalyzer class in QuantumGIS (http://www.qgis.org/api/classQgsOverlayAnalyzer.html#details) ...
2
votes
3answers
413 views

How to batch-process georeferencing of rasters (prelude to animation)?

I have many (10k) raster files, all with identical size and pixel dimensions, which need to be georeferenced. I would like to georeference one of them manually, using either QGIS or GRASS, and then ...
0
votes
0answers
59 views

Why don't libgrass.so.1.8.0 and libqgissqlantconnection.so.1.8.0 load?

I have compiled Qgis 1.8 at Ubuntu 12.10, but some phyton plugins does'nt work, like sextante. Trying to solve this problem, some files don't have been load. They are: libgrass.so.1.8.0 and ...
0
votes
0answers
73 views

Built QGIS installer with own GUI

I would like to build/compile a QGIS installer with my own customized GUI. Does anybody of you has some experience with it or some help material (links, documents, ...). Is it possible to create a own ...
1
vote
0answers
339 views

“topo to raster” tool

is there any analogue of "topo to raster" tool (ArcGIS) in QGIS? I need to creates surfaces from shp for some cases from points and for some from lines and this instrument is very convenient.
0
votes
1answer
49 views

How to use classified styles with joined layers?

I am trying to set a color range based on this tutorial In LAYER PROPERTIES for "new", in JOINS, I have joinlayer - data-join joinfield - GEO_ID2 targetfield - GEOID10 Where "new" is my shapefile ...
0
votes
1answer
135 views

PostGIS Manager Load Error [duplicate]

I am using the PostGIS Manager Load data to PostGIS tool on a Windows install and am getting the following error: Something's wrong: ["'shp2pgsql' is not recognized as an internal or external ...
21
votes
1answer
782 views

What does the adoption of Python by NVIDIA for GPGPU mean for GIS?

Today NVIDIA announced support for the Python language on its flavor of GPGPU (CUDA). Manifold GIS uses CUDA to enable some accelerated raster operations but it is not a programmable environment and ...
2
votes
1answer
198 views

Which BC Albers should I use and is there any difference?

I was about to calculate the area of some polygons and before I did I did some research. I found that the area of the polygon will be represented in the units of the projection used. So I did some ...
2
votes
1answer
2k views

How to use QGIS from command line on Windows

I have QGIS running on a windows operating system. I am willing to use QGIS from command line to follow this procedure. Unfortunately, i cannot manage to have qgis declared in the command windows. I ...
0
votes
0answers
265 views

QGIS WMS didn't show georeferenced tiff

I try to reference image and use them via WMS. Chouse project CRS to EPSG:900913 Add OpenStreetMap source using gdal wms <GDAL_WMS> <Service name="TMS"> ...
2
votes
3answers
409 views

Coordinate System (Malaysia RSO Projection) not lining up in QGIS and ArcGIS for Desktop?

I am using QGIS 1.9.0 on Linux Mint; and I am new to (Q)GIS I have three layers (2xshapefiles, 1xopenlayer[Bing Maps]) that I am trying to line up located in peninsular Malaysia. Shapefile_1 is a ...
2
votes
1answer
133 views

Raster export for regressions analysis

I have the following issue: I am trying to do a regression analysis between the (z) values of two rasters. What I would ideally like to have is the raster output not as grid but rather a list of ...
3
votes
0answers
177 views

Can you set a QGIS print composer to render the map as default?

I have set up a number of templates for the print composer in QGIS. In the Print Composer, there is the option to have the map image displayed in 3 ways: as a blank rectangle with no updates until ...
0
votes
1answer
252 views

qgis how to assign a field to map tips

I am a beginning user of QGIS 1.8. I cannot find the way to assign a field to 'map tips'. There seems to be no way in 'properties' of the layer to do so.
0
votes
2answers
966 views

QGIS: using postgis can I define a layer using sql?

I have a vector layer (call it master) that is stored in postgis and consists of a number of line segments. I also have a collection of sub layers that consist of subsets of the master layer. I can ...
2
votes
2answers
269 views

How do I plot data stored in an attribute table (really in a database) in qgis

I have a csv of UK postcodes from Ordnance Survey that looks like SE1 0AA,10,531869,179427,E92000001,E19000003,E18000007,E09000028,E05000536 When I import to QGIS using 'Add Delimited Text Layer', ...
0
votes
1answer
95 views

What could I do to make QGIS find all the plugins?

I'm starting to use Ubuntu 12.10 and would like to get my QGIS running on it. Installation was fine but when I tried to add a package called Points to Paths the Plugin Manager was unabled to find it. ...
1
vote
1answer
82 views

Shapefile CRS damaged. How to bring it back?

I have two shapefiles with same location and extends (EPSG 4326). But one of the shapefiles CRS seems to be damaged after doing a lot wrong with reprojection... its not shown on the same position as ...
2
votes
2answers
237 views

How to create a matrix of points inside a polygon with QGIS?

I need to create a matrix of points (e.g. 3.5 x 0.5 meters), with a defined orientation, inside a polygon. Essentially, I have to plan the arrangement of plants in a grove in order to plan an ...
5
votes
3answers
308 views

How to combine stacked polygons within a shapefile?

The image below shows my shp-file. Every polygon has the same transparent color. So a darker blue means, that several polygons are stacked! How do I cut every polygon with each other so no polygons ...
1
vote
1answer
357 views

How to do spatial adjustment of Line features by edge snapping in ArcGIS?

I have two polyline features of same area which are prepared based on two different raster imagery. Hence the two features are not exactly matched and has some shift. How can I adjust them to overlay ...
0
votes
1answer
278 views

CRS is UTM 51, the coordinates are shown in meters, show same coordinates as lat long as well?

We are working with a CRS of UTM 51N, the Philippines. The coordinates under cursor are shown as metric values. Clients however like so see the Latitude Longitude values when they move the cursor. Is ...
2
votes
1answer
293 views

How to zoom to specific lat/long point in QGIS

Does QGIS have the ability to Zoom to a specific lat/long point upon the user entering one. I can see it shows the coordinates in the bottom task bar but I'm not seeing a way to manually enter ...
0
votes
1answer
274 views

Using Easy Custom Labeling: Where's my missing label?

I’m using the Easy Custom Labeling plugin (with QGIS 1.8). I have one feature label which refused to show itself. It’s just not visible. When I look at the attributes table, the feature name appears ...
1
vote
2answers
1k views

Convert KMZ image to UTM projection jpg file

I have some KMZ files that are basically aerial imagery that has been referenced to Lat/Long. I would like to convert them to a projected UTM coordinates such as NAD 83 in a geo-jpg format. I was ...
2
votes
2answers
2k views

How to install the Python module shapely for QGIS use?

I'm using QGIS 1.8.0 on a Mac with OSX 10.6.8 (Snow Leopard). I've installed QGIS including GDAL, GSL, UNIXImageIO, Freetype, and Matplotlib all from www.kyngchaos.com. When installing the plugin ...
4
votes
4answers
401 views

How to display a “Save As” dialog for raster files?

I'm writing a QGIS plugin in python. I need to show a "Save as" dialog window in order to allow the user to select the path of the output raster file. Do I need to create a QFileDialog and manually ...
1
vote
1answer
63 views

QGIS 1.8.0 Mac where is measure window or measure area symbol?

Just trying to measure the area of a selected polygon (a few km2) but can't find out where the measure symbol is (mentioned in some posts here) or how to get the measure window shown in the manual. ...
0
votes
1answer
184 views

OpenLayers Plugin won't render maps correctly

In QGIS, I've created a map by adding a Tiger layer of my county, a KML of a water feature, and a geo-coded CSV of points of interest. I'm trying to add another layer using the OpenLayers Overview. ...
4
votes
1answer
252 views

Getting Transparent Circles with Heatmap Plugin

With QGIS, I am trying to create a heatmap from a set of points I added as a layer using the "Add Delimited Text Layer" plugin. The points are a collection of complaints from around a city and I ...
1
vote
2answers
269 views

How to create Concentric Circles in QGIS?

I'm trying to build a planning tool for center pivot irrigation system. It involves selecting a field (polygon), a center point, and then an outer circle to set the outer limits of the system. From ...
1
vote
1answer
54 views

How to install an old QGIS Master (1ab5cdc)?

I need to revert my current version of the QGIS Desktop Master back to 1ab5cdc (about 5 months ago). Anyone know how I can make this happen? I'm running windows XP
3
votes
0answers
98 views

Can layers from Spatialite db be used as input for a Sextante model?

I'm trying to build my first models in SEXTANTE and already fail at the start. It seems not to be possible to add a vector layer which derives from a database. Orginally, the layers are from a .mdb. I ...
1
vote
1answer
221 views

Is there anyway to modify thickness & color of a selected polygon?

QGIS - version 1.8.0. Is there anyway to modify the thickness and color of a selected polygon (Select Single Feature)?
2
votes
3answers
474 views

How can I use jp2 aerials photos in QGIS?

I have previously been able to add raster data in the jp2 format to QGIS. I am able to do so on 1.8 installed on my laptop. Unfortunately when I attempt to do this on my desktop, it claims that the ...
1
vote
1answer
376 views

“Easy Custom Labeling” arrows: How do I get them?

I have installed the Easy Custom Labeling plugin, but haven't figured out how to make the "Generate lines" function work. When I click on the tool in the toolbar, it opens the dialogue to specify my ...
3
votes
2answers
1k views

How do you change the editing capabilities on a MapInfo .Tab file?

When I load a .Tab file into QGIS I am unable to make changes to it. The information on the MetaData Tab reads the following: "Editing Capabilities of this layer: Add Attributes, Fast Access to ...
2
votes
1answer
85 views

Is it possible to use a WHERE clause with Grass v.in.ogr for DGN sources?

I am trying to import a .DGN with Grass v.in.ogr in QGIS. I am able to import the DGN perfectly, but I would like to filter the elements using the WHERE option. From searching, reading and testing I ...
1
vote
1answer
122 views

Split polygons and extract points

I have a polygon file with 90 adjacent polygons. I also have a lat/long point file that overlaps the entire surface of the polygon file (170,000 points). My problem is that working with all of the ...
1
vote
1answer
76 views

Syntax in Qgis "Rule properties?

I struggle with Qgis and some drawings of water pipes for a water company. According to the program it is possible to place different signatures for different components (stopcocks, T-pieces, etc.) ...
2
votes
1answer
192 views

How to work out sqft/m of land coverage?

I am currently self teaching myself on qgis whilst volenteering on a project on a river catchment and your help is hugely appreciated! I need to be able to work out the percentage of land cover or ...
1
vote
1answer
121 views

Projection WGS 84 is slightly displaced referring to a hillshade in QGIS

I have a hillshade and a vector layer. The vector layer is slightly displaced referring the hillshade. About lat=100m and long=175m The CRS of the project is EPSG:3397 - PD/83 / Gauss-Kruger zone 4. ...
2
votes
0answers
55 views

QGIS 1.8.0 Mac can't create ring

Can anyone spot what is wrong here? I've selected single feature, the existing rings are obvious, it's not intersecting anything (even a feature in another layer...
2
votes
1answer
643 views

Following previous instructions to set up adding ecw files to QGIS does not work

I have followed the solutions to setting up ECW in QGIS. However, none of them work. In addition I get a mount - access denied error when trying to load the gdal-ecw and gdal-mrsid plug-ins using ...
2
votes
1answer
484 views

Grass v.clean.snap with Polygons

I am doing some topology testing using Grass in QGIS. I am hoping to snap nodes to eliminate gaps between polygons. When I use the v.clean.snap function in Grass it does not work on polygons. When I ...
4
votes
1answer
322 views

Topology problems with QGIS/GRASS

*edited file links below I'm working on several NGO projects at the moment, all of which are reliant on being able to use a district level map with some 490+ features, and I am running into some ...
2
votes
1answer
1k views

Either GeoJson to TopoJson conversion problem, or projection-issue with D3.js

My 'handcrafted' cartogram (How to create contiguous area cartograms in QGIS or R?) is ready to embed in code - I want to present it online with D3.js. Therefore I produced a topoJSON file of it - ...
1
vote
3answers
701 views

How to make polygon from cells of a raster?

I have 100 rasters, each raster has the same cell size and extent and i want to make a polygon of each cell. Can anyone help me doing this?
2
votes
0answers
53 views

Why does Field Calculator put in all these 9's?

I’m trying to update some GPS point coordinates in an attribute table using QGIS Field Calculator. However, regardless of whether I do it by creating a new field or updating an existing one, I get ...