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

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4
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1answer
2k views

How to display places names when using Quantum GIS and shapefiles?

I am new to the world of geo systems. What I would like to do is displaying some information on a map for given regions. I downloaded shape files from cloud made web site and load layers using ...
4
votes
4answers
4k views

How to import qgis.core to python app?

I'm new to Python. I want to create GIS app with Python using QGIS library on Window 7 64bit. The way I do: install QGIS 1.7.0 I set PYTHONPATH=D:\Program Files (x86)\Quantum GIS ...
5
votes
1answer
135 views

How to keep Table Order in Identify Results?

Is there a way to keep the default table order when using the "Identify Feature" tool. I see that you can sort the "identify results" by table column name or value. I don't want the data in this view ...
3
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3answers
1k views

How to extract the US from a North America Shapefile?

I have a north america shapefile, downloaded from ftp://ftp.epa.gov/wed/ecoregions/cec_na/NA_CEC_Eco_Level2.zip How can I get a new shapefile from this showing only us? Is there a way doing this in ...
3
votes
3answers
870 views

How to add a raster legend with min/max values in QGIS 1.6?

I calculated/made NDVI with landsat data using ERDAS. Results of NDVI is in black and white map but I need it in colour to present the scale for NDVI with value of pixels in Map Composition. How to ...
1
vote
1answer
729 views

Why does qgis become unresponsive when adding a .sid raster layer?

Can someone provide insight into why qgis becomes unresponsive when i try to add a raster layer? Specifically a .sid raster from NAIP imagery. I can no longer add these raster layers to projects, even ...
2
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1answer
522 views

Why does intersect not calculate polygon areas?

this is strange: I intersected 2 shape-files and the resulting shape does not contain the Shape_Area and Shape_Length of the intersected polygons. Instead the field Shape_Area contains the ...
2
votes
2answers
782 views

How to control line width in legend in QGIS?

I have a map in which I am defining the sizes of various features in map units. When I come to generate a pdf of the map, using the Print Composer, the map itself is fine, but when I include a legend ...
0
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0answers
253 views

QGIS GDAL integration of new version [duplicate]

Somewhere else on this forum ("How to access file geodatabase in Qgis?") someone asked how to access data from an Esri file geodatabase in Quantum GIS? One of the answers pointed to ...
5
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0answers
616 views

How to get rpy2 for QGIS on OSX?

I am a new QGIS user, have installed QGIS on a Mac running Snow Leopard OSX 10.6.8 following all the instructions. QGIS seems to work well for everything other than when I boot up I get the message ...
3
votes
2answers
4k views

How to export a raster layer for external processing?

Is there a way to export all values from a raster to for example a cvs or other textfile or dbf or xls and later import (changed) values from that file back into the raster? For vector-files this is ...
2
votes
2answers
3k views

How to exclude missing values from raster layer?

In my raster layers the value -999 means "missing". Those points completely mess up any colormap in qgis because qgis treats them as normal values and includes them in the classification. I would ...
2
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0answers
542 views

Trouble with Python plugins on QGIS [closed]

This question has been bugging me for a while now, and I still haven't managed to solve it, so I'm giving it another go, hopefully someone may help me out. I've been having problems loading several ...
2
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3answers
1k views

how to extract a rectangle corner coordinates in python script

i want to extract a rectangle corner coordinates of a shape file in python script..please suggest me a solution. Thanks in advance, Bhavya
3
votes
3answers
1k views

Is it possible to create multiple buffers using QGIS?

I'm new to QGIS and have no programming skills, is there an easy/uncomplicated way to create multiple buffers around a line feature.
0
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1answer
398 views

GRASS and QGIS- “ not recognized…format” but it worked before

Prologue: I used my Ubuntu file viewing GUI to move data files around and "clean house" a bit. I started a new GRASS session and tried to add NED elevation rasters which I have successfully added ...
11
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3answers
15k views

How to convert a vector layer to raster?

In qgis in the raster menu there is an item "convert vector to raster". This behaves strangely - I do not understand how it is supposed to work. I can select a vector file, an attribute and an ...
5
votes
6answers
4k views

How to georeference a dxf?

I have got myself a dxf which is built with units in the wrong scale. How do I upscale that in QGIS? Note it does open in QGIS, just in the wrong map units and location.
1
vote
1answer
467 views

How to create one shapefile from multiple rasters?

Ok, I have about ten maps that connect along their edges to each other linking rivers and properties. When I link them all in Inkscape I end up with a large file that won't save (and a smaller one ...
4
votes
2answers
526 views

Is it possible to automatically set CRS of Rasters from PRJ file?

I am trying to learn my colleagues to display measured data (ASCII) in maps relatively easily. I can prepare project, color and symbology style for the point layer and background map. I also found ...
1
vote
2answers
390 views

Where to choose a shapefile for appending?

I want to append several shapefiles in QGIS. The ftools 0.6.1 add-on is installed. But under Vektor>Datenmanagement-Werkzeuge>Shapedateien zu einer zusammenführen (=append shapefiles) is only the ...
6
votes
2answers
2k views

Why can't I edit KML/GML layers?

Newbie here confused by my first experience in QGIS I have a handful of lines defining a bike route. Originally they were saved in a .gml file and later translated into .kml so they could be viewed ...
0
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2answers
394 views

Why does only one of three elevation rasters display correctly?

I downloaded a selected sub-set of the USGS National Elevation Data (NED) using their online GUI. This download came in the form of three files. The names of the files are 61471006, 61471006_2, and ...
3
votes
3answers
1k views

How to generate heatmaps with QGIS1.9 plugin automatically?

I created a few heatmaps with the new plugin in QGIS 1.9, but now I would like to generate a lot of them automatically. How should I do? I created a few of them by hand, but I should first import the ...
1
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1answer
326 views

Looking for help identifying projections and reprojecting

Hi there at the new forum, I'm still struggling with projections in qgis. The "Vogelschutzgebiete" reprojection worked. But these ones seem to be tougher: ...
0
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1answer
586 views

How to work with OS map files from Digimap?

I am trying to add map tiles as raster files in QGIS but when I add them they all appear on top of each other. I did this once before and everything was ok but I am now unable to find how to get the ...
3
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0answers
488 views

How to export multiple Shapefiles to one KML file in QGIS?

As the title says, is it possible to export multiple Shapefiles to one single KML in Quantum GIS (Similar to "Map to KML" in ArcMAP)?
2
votes
2answers
1k views

Is there a browser/management view in QGIS?

Is there a browser/management view in QGIS 1.8 so that I can manipulate shapefiles and others (such as geo tiffs, etc.) like in ArcCatalog? Maybe a plugin? Right now I have to use my system's file ...
2
votes
1answer
358 views

Is QGIS suitable for noise modelling?

Hi I've never used any type of GIS software before so I'm trying to find out if it is suitable for what I'm trying to do: I've written a c++ program which estimates ground level noise from a distant ...
4
votes
3answers
4k views

How to combine information from raster and vector layers?

in QGIS I have 1 raster-layer (elevation) and 1 vector-layer (administrative units). Now I would like to be able to query one of the administrative units and see the mean and min/max of the elevation ...
1
vote
1answer
150 views

I would like to show points moving on a map by date

I would like to create a map where i can see points moving. I have table of points for example with a date column, A 01/01/2012 B 02/01/2012 C 03/01/2012 D 04/01/2012 E 05/01/2012 F 06/01/2012 I ...
6
votes
3answers
14k views

How to get the coordinates in Lat/long from a point layer?

Sorry for asking this basic question, but I couldn't get the solution from the previous answers. I need to extract the Lat/long coordinates of the centroids of districts. My QGIS project SCR and the ...
0
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0answers
58 views

What projection is this [duplicate]

Possible Duplicate: QGIS - Hell of time with CRS and vector intersect The tax assessor parcels layer I referred to in my first post gives this as its projection: +proj=lcc ...
4
votes
2answers
291 views

How to Intersect a layer with custom CRS with NED data?

I am trying to create a map with a layer of county tax assessor property parcels plus NED elevation data. The projection of the tax assessor layer is a weirdo -- looks like user-created by the ...
4
votes
2answers
551 views

Is it possible to generate a vector polygon from a polygon on a raster image?

I have a raster map which I have extracted from a government report providing flood extent return frequencies. I want to 'snatch' these flood extent polygons (i.e. convert to vector) and I was ...
11
votes
1answer
2k views

How do I build a custom form for entering attributes in QGIS

I've done this many times in ArcGIS and ArcPad but I don't even know where to start building a custom form for data entry in QGIS. I would like to do this for field operations--QGIS would make a good ...
1
vote
1answer
238 views

Heat Map to find 10 restaurants, 10 retail, and 10 stores open after 6pm within 3 linear blocks

I would like to find where in the City there is a combination of 10 restaurants, 10 retail, and 10 stores open after 6pm within 3 linear blocks. What is the best way to do this? What data would I need ...
6
votes
2answers
2k views

How do I layer stack rasters in QGIS?

I have some multi-spectral data, where the individual bands are separate Raster files. How do I layer stack these rasters so that I get one raster with 3 bands instead of 3 different rasters? This ...
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0answers
459 views

How to do Kriging using SDA4PP in QGIS?

I am trying to do kriging using SDA4PP. I have added a delimitted text layer and wish to krige that. When I try I get an error message from SDA4PP as follows... This tool requires at least one ...
6
votes
3answers
2k views

Are there any issues going back-and-forth between Quantum GIS and ESRI software?

A very simple question. I have very simple work tasks at the office (digitizing) that I would like to be able to work on at home because we are exceptionally busy. I don't want to spend thousands of ...
19
votes
2answers
18k views

How to access file geodatabase in Qgis? [duplicate]

How does one access data from an Esri file geodatabase in Quantum GIS? I've seen snippets of conversation that indicate it's possible with qgis 1.7+ and gdal 1.9+ but no clear recipe. I recognize ...
1
vote
1answer
2k views

Do QGIS Field Calculator xat(n) and yat(n) functions work in version 1.7.x?

I'm trying to use the xat(n) and yat(n) in the Field Calculator but can't get them to work. Does anybody have an example how to use them? I need the start and end coordinates for line segments, does ...
2
votes
2answers
1k views

How to handle AutoCAD Map to QGIS workflow?

I’m looking for some assistance and like many here, I am pretty much a GIS novice. I’m working on a project to map our local cemetery (about 40 acres), locating sections, lots, and graves, etc. I ...
5
votes
1answer
5k views

How can I load .adf files to Quantum GIS?

Is there a possibility to load .adf files to Quantum GIS?
7
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1answer
518 views

How to reset QGIS to 'first run' state?

The title sums it up, I'm trying to reset QGIS to its first run state under Windows 7 and XP. Deleting the .qgis folder in my user directory goes a long way to achieving this, but certain things ...
3
votes
1answer
508 views

How to create custom markers for QGIS?

Is it possible to define a custom marker as symbolizer for a point in QGIS? I'm looking into using a variation on the "Vector Field Marker" with a couple of arrows pointing at dynamic angles (the ...
1
vote
2answers
288 views

How to specify the desired WMS version in Quantum GIS?

How can i set a WMS version of layer which i want to display. I am asking because some WMS addresses are still served via older versions like 1.1.1. In short, I am looking for the equivalent of this ...
4
votes
2answers
3k views

How to create heatmap (concentration of points) in QGIS?

There was already a question about it in 2010, where the answer was basically "use QGIS Heatmap plugin". I've also read on QGIS webpage that it is now "implemented as a native C++ plugin" My ...
10
votes
4answers
4k views

How to export shape file to SpatiaLite

I have a shapefile with one layer. I can open it with QGis. Now I want to convert this shapefile or layer to Spatialite database. How can I do it? Is it possible to do with QGis?
3
votes
1answer
2k views

How to install SDA4PP plugin for Kriging in QGIS?

I am trying to do kriging in QGIS. I have loaded the SDA4PP plug in. Almost all of the items in the SDA4PP dropdown menu are not highlighted and are unresponsive when clicked on - including the ...