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

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1answer
169 views

Problem with projection of layers in QGIS

I'm having a problem with projections in QGIS that i hope someone here can help me with. I have been searching and found other people having the same problem, but have not been able to solve mine ...
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5answers
11k views

How to quickly calculate bounding box coordinates of a selected polygon with qgis

I just manually (and somewhat inaccurately I'm sure) retrieved the bounding box coordinates for a county polygon, which is a selection from a larger layer of county shapes. I'd like to be able to use ...
1
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0answers
415 views

How to add a MSSQL spatial layer using Python?

I'm having difficulty adding a MSSQL spatial data layer using Python. The database is password protected, and I can add the layer without any problems using the built in feature, but I can't make it ...
1
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1answer
112 views

Problem using pgRouting 2.0

I follow this great post:pgRouting 2.0 for Windows quick guide, and I have loaded the test data from GeoJSON, like this: But I don't know how to load this layer into my database, and my DB manager ...
2
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0answers
664 views

Calculating area with python qgis

I am a little stumped with determining the area of polygons in the python console. I want the output to be in meters^2, so using: qgis.utils.iface.mapCanvas().setMapUnits(0) ...
3
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1answer
109 views

How to create a printable data sheet when using edit widget “value realtion” in QGIS 2.0?

I created a spatiaLite Database with a point layer (every point is a tree). Additional I created several tables to fill the columns of the spatial layer with attributes using the editing widget “value ...
3
votes
1answer
292 views

How can I specify certain quantiles for renderer classification?

For graduated classification in QGIS 2.0.1, I can choose between several statistical methods to classify my data (standard deviation, quantile, natural breaks...) and for each method it is possible to ...
4
votes
1answer
602 views

Cannot compute area of shapefile in field calculator of QGIS?

This shapefile represents the counties of NM. I am trying to compute the area of each polygon (yes, I know there is an area field, but this is a simpler example of a problem I'm having which doesn't ...
1
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1answer
153 views

How do make a CSV file visible in QGIS?

I am using QGIS. I have a .csv file containing 3 pieces of information on each row; name, longitude and latitude. I would like to turn each row of the .csv file into a vector point. The file will ...
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1answer
1k views

What can I do with this unzipped GDB file in QGIS?

I have a zip file that I got from the City department of information technology. Unzipped, it is a directory called DOITT_ZIP_CODE_01_29JUL2009.gdb containing a bunch of .gdbtable and .gdbtablex ...
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3answers
1k views

Unmet dependencies installing QGIS 2.0 on Ubuntu

I have followed the instructions-a link to install QGIS 2.0. Everything worked fine until the punch line, installing QGIS ( I do have Ubuntu 13.10); sudo apt-get install qgis python-qgis ...
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0answers
116 views

Why does GDAL Translate not create any output in batch mode?

Has anyone tried using the Batch Mode function in GDAL translate - qgis2? I can process files individually ok, in my case MODISA HDF files. But the batch mode does not seem to work. Here is my set ...
0
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1answer
205 views

Trouble connecting QGIS 2.0 to remote Ubuntu Postgis

I am trying to connect to a remote postgis 2.0 server (Ubuntu) from QGIS 2.0.1 (installed on winxp). I have been working with QGIS 1.7 / 1.8 on the same database for almost a year without any issue. ...
1
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3answers
313 views

How to Project a point on feature in PyQgis?

In Arcgis IProximityOperator.QueryNearestPoint Method was available to get the nearest point. Similarly Is there any function available in pyQgis? Thanks in Advance.
1
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1answer
277 views

Join Tables related by a composite primary key in qgis

I have two tables, one has the geometry and other has attributes. The table with geometry has unique number primary key, and 4 columns admin1,admin2,admin3,featureid. Table two is a csv file has the ...
2
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0answers
107 views

Is there a way to build topology and work with topology relations in PyQGIS?

Is there a way to build topology and work with topology relations in PyQGIS? I'm asking because I need to run some custom generalization algorithms on my data, and I need to preserve topology. ...
2
votes
1answer
694 views

How to mosaic Landsat 7 images correctly?

This is a result of mosaicing of two Landsat 7 images (layer stacked) in TIFF format. I was aming to put these images together with no overlaping visible line between them. The process was: Added ...
6
votes
2answers
745 views

How do I set the composer layout units to inches?

I open an new composer and select ANSI A for my paper. The notation after the name is "Letter; 8.5inx11in", but the width and height are displayed in mm, and the units selection is grayed out, so I ...
1
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1answer
63 views

Can I offset the map frame in the composer?

I have a map frame in a layout in which the map fills the frame. If I check the frame property checkbox, there is no whitespace between the contents and the frame. Is there a way to offset the frame? ...
0
votes
2answers
650 views

How to change the aspect ratio of a map without the scale changing? [duplicate]

The aspect ratio of the map frame doesn't match the contents, leaving a lot of white space inside the frame, even after I've scaled the contents to fill one dimension. When I drag one edge of the ...
2
votes
2answers
84 views

Is it possible to customize the Vector and Raster menus?

a little but nervous problem. As you know QGIS offers the possibility of strongly customize all the menu, toolbar, statusbar,... thanks to the option Customization in the Settings menu. Here the ...
3
votes
1answer
216 views

Is it possible to label bar charts?

I have added bar charts to my map and this works fine. But I have no idea how to add values to the bar chart. For example one bar shows the value of 2000 and another shows the value of 2100. Is it ...
0
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1answer
156 views

problem display tile when config tilecache for WMS

i have a problem with config tilecache for WMS when i have shown it. but there are proplem when display tiles. any idea? this is my config for tilecache.cfg [world] ...
7
votes
3answers
27k views

How to make work tablet integrated GNSS (GPS) on Windows 8 with QGIS?

I have tablet - Dell latitude 10, running Windows 8, with integrated Broadcom GNSS Receiver BCM47511 (GPS,Glonass...). Because it is integrated GPS and Windows 8, there is the "new" way of providing ...
2
votes
2answers
319 views

How to use QGIS Atlas with multiple layers/files per coverage?

I've got 30 contour datasets that all sit over the same extent. Each contour set is in its own file. I also have 30 extent polygons for each contour set as a separate file. Can I use Atlas to ...
3
votes
2answers
10k views

How to clip a line layer based on polygons with QGIS?

I have a line layer and a polygon layer. Both files have the same SRS. I want in a new shape file only the lines covered by the polygons. I tried in QGIS the Vector -> Geoprocessing -> Clip ...
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0answers
966 views

How to convert lines to start points and end points?

I know there are several ways to convert lines to points in Qgis but I have not been able to find a solution that will convert the file so that it indicates if the point is the start point (upstream) ...
3
votes
2answers
2k views

Read gpx track points in QGIS

I want to read GPX track points with their time stamps into QGIS. I try GPS Tools, GPX Conversions, Waypoints from a track. This fails on my PC at office (QGIS code revision d94c044). Sometimes QGIS ...
0
votes
1answer
377 views

Set QGIS vector layer custom properties

I'm trying to set some labels and styles for some vector layers that are loaded programatically from a Spatialite database. I have the following code, which returns no error, and includes the changes ...
0
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1answer
281 views

How can I always run an algorithm with standard input shapefiles from mapcanvas in QGIS 2.0.1?

I created a model in the graphical modeler and I want to run that model always with two specific polygon shapefiles from my project, e.g. pst and astenot. Whenever I run my model, it asks me to set ...
0
votes
1answer
765 views

Field Calculator - replace string function - data value recognised as a column and is “not found” [closed]

I have the same challenge as GrahamD - Field Calculator - replace string function I have exactly the same challenge. Exactly the same as GrahamD's challenge, p abbreviated for pan. Type_2 as a test ...
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0answers
207 views

Why does the SAGA raster calculator fail when used in a Processing model?

I have a problem with the modeler and the saga raster calculator. When I'm using the raster caculator without the modeler it works fine. When I'm using the saga raster calculator in my model I always ...
2
votes
1answer
690 views

Qgis OSM and layer projection problem

I am using QGIS 2.1.0, and trying to import my vector layer(parcels) with OpenStreetMap layer. My vector layer (parcels) use EPSG 31277 coordinate system. This is the definition for EPSG 31277: ...
2
votes
0answers
620 views

Google Maps Engine Connector error

I have recently installed the Google Maps Engine Plugin for QGIS 2.0 and it doesn't seem to work. Whenever I click on the Log in button it pops up with: Google Error:invalid_client Bad request. ...
1
vote
3answers
606 views

Table Relate Spatial and Tabular data in QGIS 2.0

I am self taught in GIS, so I apologize ahead of time for my noobness. In ArcGIS you have two options to associate data in a table to spatial data. Based upon my understanding, the first is Join ...
2
votes
1answer
137 views

How do I create smaller maps for publishing from multiple tiles representing a large map using QGIS?

I am completely new to cartography and QGIS - I'm a writer, editor and acceptable designer (Adobe Creative Suite). I wish to produce PDF tour guides featuring maps that display a route. One version ...
3
votes
2answers
4k views

How to use the replace string function in Field Calculator?

Within an attribute table I'm trying to replace one string with another using the 'replace' function . As an example, there are a number of features whose field 'NAME' contain the string '(B)' and ...
2
votes
1answer
149 views

Loading / georeferencing OS rasters in QGIS

I have got some OS rasters but there isn't georeferencing file (TFW) with them. When I try to load them, it will obviously load in the wrong place. They are loading fine in a different GIS software ...
1
vote
1answer
191 views

What is the 'water retention capacity' tool and how is it used?

In the latest version of QGIS, I found a geoalgorithim in the processing toolbox that will generate 'water retention capacity.' I am familiar with DEM-based hydrologic modeling tools in QGIS, but I ...
1
vote
1answer
245 views

QGIS how to compute a trendline of two point lines? [closed]

Does anyone know how to compute a trendline for two lines of points? I have two lines of points of a 10 km long urban road. 1st line is one driving direction and the 2nd line of points ist the other ...
1
vote
3answers
886 views

How to access user credentials in database connection?

I am trying to automate a couple of things when a QGIS plugin is activated: If Layer A is not in the TOC, add it. This requests username and password to access a PostGIS table using the inbuilt ...
3
votes
3answers
1k views

How to draw (or add) a line indicating a specific latitude/longitude?

I'm trying to add a single line that show a specific latitude (e.g. the Tropic of Cancer) I don't want a gird but only a single line even in a vector layer.How can I do that I've try with pyQGIS ...
2
votes
0answers
420 views

Editing of vector layer programmatically with QGIS

I'm trying to edit vector layer using Python console and have couple of questions. Why this approach doesn't work and I have to use canvas.refresh? If I will use this code not in python console but in ...
0
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0answers
69 views

Problem with GRASS in QGIS

I am trying to import a vectorlayer to GRASS from QGIS. I get an error and hope someone here can help. Been trying to fix it for hours, but come no closer to a solution..... This is the error I get: ...
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1answer
226 views

How to fix QGIS crashes when using GRASS toolbox?

I've installed QGIS 2.0.1 on Ubuntu 12.04. exactly as explained on qgis.org . Unfortunately QGIS crashes when trying to use any GRASS model (r.aspect as example): just opening QGIS, click on toolbox ...
4
votes
2answers
2k views

keep the same field headers after joining a table to a shape file in QGIS

I noticed that after joining a table to a shape file the headers of each fields in the table used for the join are changed by QGIS and they are attributed to a different name. For instance, i had a ...
4
votes
2answers
148 views

How to replicate trunc function on QGIS?

I've search a bit before asking this question, but I haven't found the answer. Is there a Trunc function on QGis? I've tried using floor, but it doesn't work (like I want) if the number is negative, ...
1
vote
1answer
304 views

Is there a way to automatically calculate attribute values for new features?

I am creating a vector point layer which will be added to over time. I have been using the field calculator to populate fields such as X and Y coordinates. I'm wondering if there is a way to have ...
3
votes
1answer
2k views

How to pick the coefficient in Inverse Distance Weighted method?

I'm using QGIS 1.8.0 to interpolate weather data. This is, I have a weather station located in say, A and C. With the Inverted Distance Weighting or Triangular Interpolation methods, I can ...
0
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0answers
884 views

Trying to make QT + QGIS working

I'm mostly a Java programmer, I worked on C++ many years ago, and knowing this my project manager has asked me to create a little app in Qt that can open a shape file, using QGIS. But I'm encountering ...