The Islands of Jean-Jacques Rousseau

[Une version révisée, en français, de cet article, publiée dans Le Temps, Genève, en 2012, peut être téléchargée ici.]

Jean-Jacques Rousseau would have been 300 years old today. He was already 53 in October 1765 when he left the waves of the Lake Bienne, heart-sick, expelled from the Island of St. Peter upon the order of the bailiff of Nidau. […] Continue Reading…

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 you have to do first is […] Continue Reading…

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 communes outside of the canton, […] Continue Reading…

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:

Bitmap strips (detoured in orange) and vector polygon layer (in blue)

In this – as in many other situations – you might need to crop the image […] Continue Reading…

Fifty years of orbital tourism

Today, the United States are celebrating the 50th anniversary of John Glenn’s orbital flight: three tours of the globe in less than five hours. To mark the occasion, Craig Russell of Space Operations Inc., would have liked to see the mission replayed, but relying on private means only, this time. We get his point, because times have changed since […] Continue Reading…

Foucault’s left-overs and the urban heterostasis

Michel Foucault, in his 1984 essay Des espaces autres (Other Spaces), coins the term “hétérotopie”. He uses it to designate places evolving on the margin of what we could today call the territory of production. Foucault’s heterotopoi are cemeteries, brothels, prisons, boats, psychiatric hospitals… places inhabited by those who’ve either been excluded from society, or are no longer its […] Continue Reading…

Mars as a social question

“Allopatric speciation” occurs when a biological species divides in two distinct populations, due either to the emergence of a natural boundary (river, mountain) or to migration in opposite directions. Over hundreds of generations, the genotypes of both populations evolve on their own until, finally, they become two separate species.

For some species of fruit-flies, this operation takes but months.  For […] Continue Reading…

Babylon and the City Recipe

Up to the beginning of the 20th century, the Ancient Testament had been the most cited text in societies with Christian heritage when it came to condemning the human hybris and its emblematic spatial figure: the city.  Yet, quite surprisingly, the most anti-urban text contains the perfect set of ingredients to build one. As the prophets write, “behold”:
“The whole […] Continue Reading…

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 tool which takes seconds […] Continue Reading…

The tourist as the main inhabitant of a place

Hotel and para-hotel overnight stays in Switzerland in the year 2000. Total numbers and comparison do the residential stay-times.

Who’s the real inhabitant of a place? For a long time, population maps have been constructed as if everybody stood still in their homes. Yet leaving this “domostatic” perspective is to geography like opening Pandora’s Box. All objects of any concern […] Continue Reading…