Update of Zim-wiki export template for an adaptive website

A short note that I updated my export template for a adaptive website to work with Zim 0.61. You can find it on my github page. It is very much work in progress, but perhaps it will be useful to somebody.

Examples of websites that were created using this template are http://notebook.ecodiv.org,http://maps.vegetationmap4africa.org/docs.html and http://www.penwatch.net/morrowind_dnd_zim/.


Exporting your GRASS raster using r.out.gdal? Check the createopt options!

GRASS GIS can export your raster layer in most common (and quite a few less common) data formats using the r.out.gdal function (menu: file – export raster map – common raster formats). Exporting is so simple that you may forget that depending on the output format there are different options to optimise your output raster layer. Continue reading “Exporting your GRASS raster using r.out.gdal? Check the createopt options!”

Sampling raster values at point locations in QGIS – an update

In a by now fairly old post I described how to sample raster values at point location in QGIS. The method I described used the ‘Point Sampling Tool’ addon. However, the function creates a new point layer, which only contains the values extracted from the raster layer. None of the fields in the original point layer is copied to the new one. It is possible to join the attribute table of the new vector point layer with the original attribute table afterwards using a spatial join as explained in that post. However, this will not work if your point data includes points with exactly the same coordinates.

Since I wrote that post, QGIS has come a long way. Continue reading “Sampling raster values at point locations in QGIS – an update”

Using GDAL from within QGIS: trouble shooting

Some notes to self about steps I had to take to make GDAL work from within QGIS. Both where compiled from source and run without problems. However, there are still a few issues with running gdal from the QGIS processing toolbox. This may have to do with the fact that I installed both in a non-default location (in the /usr/local/ folder), but in any case, the steps below solved the problem for me. Continue reading “Using GDAL from within QGIS: trouble shooting”

Installing Google Earth on Ubuntu 14.04

Since Ubuntu 13.10 Google earth cannot be installed out of the box on Ubuntu 64-bit systems because it  requires the deprecated ia32-libs package. The previous solution I wrote about, for Ubuntu 13.10, did not work this time. I got Google Earth to run, but it crashed all the time.

I then found the googleearth-package which downloads the latest stable Google Earth installer from Google and creates a package for you. You can then install and remove the created package at will.

But the easiest solution, Continue reading “Installing Google Earth on Ubuntu 14.04”

A Zim-wiki export template for a adaptive website

I wrote before about Zim, a graphical text editor used to maintain a collection of wiki pages. Although mostly aimed at individual use, notebooks can also be shared as html files (and a few other formats) by exporting the notebook or individual pages as web pages, as explained here. And to give you an idea what you can get, see here an example of one of my notebooks.

For one of my projects I wanted to create a small web-site with fact sheets that provide a short description of vegetation types in eastern Africa. These fact sheets go together with vegetation maps we have created for various countries in the region. The idea was to keep the fact sheets as notes in a Zim notebook, and use the export function to create a small web-site. Continue reading “A Zim-wiki export template for a adaptive website”

Creating a raster layer with a weighted random sample of points (or, my first attempt to create a python script)

I needed to create a raster map layer with a weighted random sample of all raster cells, using the percentage of crop land as weight. I couldn’t find a function to create such a weighted sample, so I decided to create a script to do this for me. Continue reading “Creating a raster layer with a weighted random sample of points (or, my first attempt to create a python script)”