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

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18
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2answers
15k 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
1k 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
4k views

How can I load .adf files to Quantum GIS?

Is there a possibility to load .adf files to Quantum GIS?
7
votes
1answer
375 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
435 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
230 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
2k 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 ...
7
votes
3answers
3k 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 ...
1
vote
1answer
254 views

Importing a PostGIS and a Delimited Text layer in QGIS, not overlapping

I'm a beginner in QGIS, and I have a PostGIS database and a CSV file I would like to visualize. I followed the instructions in this question and the answers, but it doesn't work for me, my two layers ...
5
votes
0answers
353 views

Modify default options in QGIS [closed]

I would like to change some default QGIS options. For example, the default font used by QGIS composer on my system is ubuntu. I would like to change that. I would also like to get no border when ...
2
votes
1answer
434 views

Removing duplicate features in PyQGIS

I'm trying to remove duplicate features from PyQGIS. Manually I can do it by using "Edit -> Merge Selected Features" and then "Multipart to Singlepart" from fTools in QGIS, but can this functionality ...
6
votes
3answers
813 views

Select All records in QGIS

Is there a one step operation to select all the records in a layer or dataset in Quantum GIS? I can't find any reference to a single button, menu command or keyboard shortcut to achieve this. I am ...
8
votes
1answer
1k views

Open software tool or QGIS plug-in to make land cover classification

Is there any tool or plugin for QGIS/GRASS to make an automatic land cover classification from satellite imagery --- based on CLC nomenclature for example? Of course, it will not be 100% sure but it ...
5
votes
2answers
4k views

Rotating a vector layer in QGIS with qgsAffine (or other method)?

I would like to rotate a set of vector points in QGIS an arbitrary number of degrees around a central point (or arbitrary point). This is similar to a recent question about creating a regular grid; ...
1
vote
2answers
585 views

QGIS layers no longer overlay when Enable 'on the fly' CRS transformation is on

My QGIS project has two layers - one retrieved from GADM (administrative boundaries of Guinea Bissau) and another one of the villages collected in the field using GPS Decimal Degrees - D.ddddd. If I ...
0
votes
1answer
276 views

Generate a report or table for buffer zone

I have a polygon feature class. I create a buffer for this feature with a distance being 2 km.Now the buffer output intersect with features of the original polygon.So say for instance from the orginal ...
3
votes
4answers
2k views

How do I create a mask where the masked area can be changed by selection?

I'm working on making a mask in QGIS to have one area(county A) outlined while the other areas(counties) are under a semipermeable layer. I already know how to do this for one selected area. But my ...
3
votes
1answer
382 views

QGIS software Layer Attribute Name Length Limited to 10 characters

In QGIS software, the "vector layer" has "attribute" but the name length is limited to only 10 Characters. Is there any method to name an "attribute" to a longer name? (e.g. attribute name "building ...
5
votes
4answers
3k views

How to change field length in QGIS

I have a shapefile I made in QGIS 1.7.4. One of the fields is a String of length 80. I'd like to make the field accept longer stings, but I can't figure out how to change its length. How do I do this? ...
5
votes
4answers
6k views

Delete points on a polygon using QGIS

I'm new at this, a novice at best. I'm using QGIS 1.7.3. I simply want to select a large number of points on a single polygon and delete them. Is this possible?
5
votes
1answer
2k views

Calculating distance to points in QGIS

Is there a way of calculating the distance to the nearest points in QGIS? In ArcGIS there is a function called Euclidean Distance, which can take an input vector or raster, and generate a raster of ...
1
vote
1answer
474 views

How to customize grids in Map Composition in QGIS?

Please somebody help me out with Map Composition. In map composer how to put in georgaphical grid (not UTM grid)? And how to put only frame with ticks and annotation (not entire grid across a map)? ...
5
votes
4answers
898 views

Spatial Query from PyQGIS?

Is it possible to reach the Spatial Query plugin functionality in QGIS from a Python script (PyQGIS)? If so, how do I accomplish this? Haven't found any documentation for it, even in the C++ API ...
4
votes
1answer
364 views

How to customize QGIS for vehicle tracking?

I'm doing a project on vehicle tracking using GIS - for that I'm using the open source software package QuantumGIS (QGIS). I would like to know how to customise QGIS using the python console to edit ...
5
votes
1answer
2k views

How to capture a rectangle within the Quantum GIS software?

I want to use "capture polygon" function in QGIS software to draw the indoor office cubical which is a rectangle shape. But the "capture polygon" function is not able to draw a perfect rectangle ...
3
votes
2answers
1k views

How to insert geometries from shapefile into existing table?

I'm running into a problem trying to figure out how I should insert a GIS coverage polygon into an existing table. I'm primarily using QGIS and the PostGIS Manager plugin to handle it. After some ...
3
votes
2answers
568 views

How much information does QGIS's OpenStreetmap Plugin download?

I am using the OpenStreetmap Plugin for QGIS to download the information for my university extent. The information as I see is downloaded in vector format divided into Points, polygons and lines... ...
0
votes
1answer
622 views

Integrate QGIS with ASP.NET MVC3

I'm completely new to GIS and i'm trying to work my way into this. My goal is to integrate a simple map created using QGIS with my asp.net web mvc3 application. The main objectives would be to show ...
2
votes
2answers
2k views

Is there any tool/plugin for QGIS to easily select feature and edit attributes

I need to select polygons and change some attributes in a shapefile. I'm using Quantum GIS - I select the polygon, open attribute table and edit the attributes I want. I know there must be an easier ...
4
votes
1answer
980 views

Union, Dissolve, Buffer — multiple layers, all in one step?

I'm a new user of Quantum GIS (1.7.3) and I need to repeat a task multiple times, so I'm wondering if there is a quicker way to do the following (with three or more polygon layers - each layer has a ...
2
votes
1answer
305 views

How to query OSM tags by polygon?

I do not know whether something like this is possible but nonetheless. If I understand OSM correctly all objects essentially have associated tags based on type of object (street, building etc) ... ...
5
votes
2answers
3k views

how to create a new postgis database for usage with QGIS under windows

After installing postgresql with postgis under windows xp I have 3 databases: postgis postgres template_postgis now I try to create a new spatially enabled database in pgAdminIII: I select ...
0
votes
1answer
211 views

Running database operations against a stored GIS geometry

I'm using Quantum GIS and Postgres with the GIS extensions to store shapefiles that I'd like to run point in geometry and point in union geometries against. While it's easy to save and load the vector ...
1
vote
1answer
411 views

How to create a profile with profile points at discrete altitude intervalls, e.g. each 10 m

In both SAGA and QGIS theres a profile-from-line-function that does a nice job of creating profiles. But there's no way to control the altitude spacing. Any ideas for workflows that would allow me ...
4
votes
2answers
1k views

Using QGIS, how can I add a bounding box attribute?

I have a shapefile where I am exporting the features to GeoJSON objects with ogr2ogr based on a simple where clause. One thing that I would like to be included in the GeoJSON object is the 'bbox' ...
2
votes
1answer
539 views

Select vectors overlapping a raster

I have a raster layer with travel times from a specified point in my city's downtown. What I'd like to do is select all of the census blocks that lie at least partially within 45 minutes of downtown ...
1
vote
0answers
330 views

How do you convert a bounding box into the canvas CRS?

I need to convert the pixel coordinates of a bounding box to the same CRS being used by an existing layer. Here's the relevant code so far: # First, get the layer-coords version of the bounding box: ...
5
votes
1answer
2k views

How to copy a geometry from one feature to another without attributes?

With QGIS it's easy to add a new part to an existing feature/geometry but I can't see how to copy/paste this part from another existing feature/geometry. Is it possible? Thanks
2
votes
1answer
728 views

QGIS and satellite images band combination

When I add a satellite images as a raster in QGIS: 1. Why the image is changed, it looks like it has only one band?; 2. where is a tool for band combination? Thanks!
5
votes
3answers
1k views

Using GIS for Interactive Floor Plan

GIS is brand new to me, but I've spent a couple of days researching so that I can at least ask somewhat intelligent questions. I've decided to use QGIS I need to do an interactive floor plan on the ...
6
votes
2answers
834 views

How to create regular soil sampling grids?

I need to be able to set up a soil sampling grid at regular spacings of around 50 - 100 meters. Then export the points to a GPS so I can be guided to the points. I am new to GIS and have tried to do ...
7
votes
2answers
2k views

Cannot add plugins to QGIS on Ubuntu 11.10 Oneric

I have installed Qgis on ubuntu. it works fine but I am not getting option to add new plugins only option to manage plugins is available. Please help
14
votes
2answers
1k views

How to generalize a polygon file and maintain topology in QGIS?

my problem: I have a polygon-file in shape-format, which I need to generalize. How can "split" the polygons into lines, generalize and than "rebuild" the polygons, so that I can ensure, that there are ...
5
votes
1answer
382 views

How to divide a polyline by intersecting isochrones

I have two shapefiles, the first representing a path (a polyline with a single category), the second representing isochrons from the same origin (point 0) which intersect the above mentioned path. I ...
5
votes
1answer
2k views

How to set QGIS Python path so that I can use system packages on Windows?

Several Python packages are best installed with a Windows installer. But those installers install to the system-wide Python directory. How do I set the Python path in QGIS? I tried setting PYTHONPATH ...
6
votes
2answers
5k views

How to add feature class from ESRI personal geodatabase (.mdb) in QGIS

How do you add a feature class in a ESRI personal gdb in qgis. I understand this can be done through the option add vector layer and select geodatabase. But what after that ? It doesn't allow me to ...
9
votes
1answer
344 views

What is the best way to represent bridges using a point vector layer in QGIS?

I'm working on a hiking/biking maps of trails in the woods which sometimes have bridges that need to be shown on the map. I'm trying to figure out the best way to capture and represent them using QGIS ...
5
votes
3answers
391 views

QGIS Gazetteer query without adding data to canvas

I have a PostGIS database with 30 million gazetteer points, each have an X Y coordinate. I want to query this and then zoom map to location. However, I dont want to add the data to the project because ...