Tag Archives: QGIS

Point coordinates to polygon – part I

Posted on January 17, 2013 by

Articles about field studies sometimes (but not always unfortunately) contain coordinates delimiting the boundaries of the field study. What if you want to view those boundaries in e.g., Google Earth? In other words, how to create a polygon layer based … Continue reading →

Posted in GIS, QGIS | Tagged , , , , , , | 2 Comments

Sum up values of neighbouring polygons – a GRASS GIS approach

Posted on January 4, 2013 by

How to sum up values of neighbouring polygons in QGIS? This question was asked on gis.stackexchange, with two interesting answers. One answer explains how to use Spatialite and SQL to achieve this. The other answer, explained in more detail here, presents … Continue reading →

Posted in GRASS GIS, GIS, SQLite, QGIS | Tagged , , , | 1 Comment

From Underdark: New QGIS Symbol Packages

Posted on December 22, 2012 by

Check out this post by Underdark about two sets of new QGIS symbol packages with series of simple fill symbols based on ColorBrewer. Create work!

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Check out the new Landcover Polygon overlay function in the LecoS QGIS plugin

Posted on December 15, 2012 by

The author of the QGIS plugin LecoS came up with  a new feature which might come in handy for some of you: a polygon overlay tool. This tool can extract raster values and save them directly to the vector layers … Continue reading →

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Stratified random sampling in QGIS

Posted on December 3, 2012 by

In my previous post I described how you can create a random stratified sampling using GRASS GIS. Unlike in GRASS GIS however, QGIS has a dedicated tool to do this. You can find it under ‘research tools’ in ‘Vector’ menu.

Posted in GIS, QGIS, research tools | Tagged , , , , , | 3 Comments

Opening MODIS tiles in QGIS

Posted on November 7, 2012 by

NASA offers a very convenient web-based tool to select and download the tiles you need; Reverb / ECHO.  The tiles are in HDF format and use the Sinusoidal grid tiling system (proj4 definition: +proj=sinu +lon_0=0 +x_0=0 +y_0=0 +a=6371007.181 +b=6371007.181 +units=m … Continue reading →

Posted in Data handling, GIS, QGIS | Tagged , , , , | 4 Comments

You can now vote for your favorite QGIS plugin

Posted on October 8, 2012 by

The list of plugins for QGIS is becoming rather long, which is a testimony to how active the QGIS community is. It does make it more difficult to find and select the plug-ins for your work. And if you find … Continue reading →

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Five new awesome QGIS features

Posted on September 5, 2012 by

Check out this post on Nathans QGIS and GIS blog: Five new awesomely awesome QGIS features. See also this blog post by Anita Graser, who describes improvements to the Symbol manager in more detail.

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Exporting vector layer as kml in QGIS

Posted on July 31, 2012 by

In my previous post I described how to export a vector layer from GRASS GIS as kml file. The key was to use the dsco parameter to define the columns that should be used for the Name and Description fields … Continue reading →

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From multiple rasters to one Google earth layer

Posted on July 7, 2012 by

To create a Google earth map, I would normally export my raster layers as a geo-referenced png file and subsequently use maptiler (or gdal2tiles.py) to create the Google earth map (see here for more details). Because I want to create … Continue reading →

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