Créez votre pays imaginaire avec qGIS: une introduction à la numérisation vectorielle des données géographiques

Cet exercice vous permet de découvrir des outils de base pour la digitalisation d’une carte vectorielle dans le logiciel open source de SIG Quantum GIS. Ce logiciel peut être gratuitement téléchargé sur le site qgis.org. L’exercice est associé aux exercices “Dessinez votre pays imaginaire avec Illustrator” et “Dessinez votre pays imaginaire avec Inkscape” qu’il est […]

Dessinez votre pays imaginaire avec Inkscape: une introduction au dessin vectoriel

But de l’exercice: découvrir des outils de base pour la création d’une carte dans le logiciel open source de dessin vectoriel Inkscape (téléchargement gratuit sur le site inkscape.org). L’exercice parvient au même résultat que les deux suivants À vous de choisir celui qui vous convient. L’interface Une fois Inkscape installé, ouvrez Inkscape. Un nouveau document […]

Translate the DHM25 model of Swisstopo from MMBLT to an ARC/ESRI GRID

The digital height model DHM25 is a set of data representing the 3D form of the earth’s surface without vegetation and buildings. It is essentially based on the Swiss National Map 1:25 000. Years ago, when Swisstopo was called Bundesamt für Landestopographie, they published this data in their home-made format called MMBLT, stored in files […]

Restore “New > Text file” in Windows’ contextual menu

If you’ve changed your standard .tex file editor to Notepad2 or Notepad++, chances are that the contextual menu entry “Create New > Document file” has disappeared. To restore it, just save the following code as a .reg file and run it (thanks to Archos alias Limneos for posting the code on a SevenForums): Windows Registry […]

Colored proportional circles in ArcMap

Bivariate thematic mapping with ArcMap? Yes you can! Of course, you could also do it in D3.js (including a nice self-generated legend), or with much less effort in Quantum GIS (post in French). Whatever method you choose, colored proportional circles cannot be drawn directly on polygons, but you can draw them on points. Thus, all […]

A mobility network

Methods and tools After a day and a half of work and fine-tuning, here we go: the commuting network of all individuals either residing, working or studying in the canton Valais. I’ve used R, with the RStudio GUI, and the igraph library for R. My staring point was the mobility matrix between all communes, including […]

Crop an image in Adobe Illustrator CS3 or later

When you export maps from ESRI ArcMap to Adobe Illustrator, the raster background is by default exported as a series of associated bitmap strips, with superposed vector polygons.Here an example: In this – as in many other situations – you might need to crop the image to a specific area. Say the following rectangle: To […]

RStudio – one big step towards user-friendliness of R

R is the greatest open source statiscal programming package around. It is all a mapper need to pretreat data. Yet it suffers from interfaces that are either uggly, tedious to set up, clumsy to use or all of these. After years of glaring at the Windows interface of R, I’ve finally sutmbled upon a nice […]