The EfficientPC company, best known as a seller of energy efficient good-looking quietly operating Linux-based laptop and desktop computers, has just announced sad news:
After many happy years of service to the Linux community, EfficientPC Limited is closing down.
The reason of this decision is interesting:
our goal of bringing Linux to the mainstream has succeeded, so we gracefully retire
Happy retirement!
Greg on the Tarzan’s Boulder, final problem of the Southern Indoor Bouldering League competition that took place on Saturday December 12, 2009 in the Castle Climbing, in London:
Available also from YouTube.
If you are user of the excellent XMPP service at jabber.org you may be interested in this announcement – you should also receive it directly to your JID from Peter Saint-Andre – our precious master of puppets:
We will make a copy of the data for all 330,000 users on Saturday morning, complete data migration over the weekend, and then switch to the new software Monday morning (European time). Once we copy the data, any changes you make (e.g., adding new buddies to your contact list) will be lost, until the new software is installed and running on Monday.
Fingers crossed for the successful migration.
Martin Daly has started posting on A Higher Education with details about use case of GDAL to serve large datasets through Web:
We use GDAL to read the files, and were opening them via GDALOpenShared, so that GDAL only opened the file once and used reference counting to manage the lifetime of the GDALDataset object. Unfortunately (for us) GDAL is not thread safe. This isn’t a criticism, the fault is entirely ours for using it in this way.
Criticism or not, the reality is that we (software developers) have already jumped to an era of parallelism (count number of physical or logical CPUs in your computer) where thread-safety becomes a minimum requirement as basic as avoiding buffer overruns.
I am happy I belong to the hordes of PostGIS users. Recently I asked for a very small addition to the PostGIS manual that will explain the three basic terms of the geospatial geometry: interior, boundary and exterior.
Kevin Neufeld delivered a very well written chapter about Dimensionally Extended 9 Intersection Model (DE-9IM) with series of excellent visualisations of the non-trivial mathematics.
Moreover, Kevin started completing the PostGIS Functions Reference with visual presentation of geometric problems together with SQL commands using various PostGIS functions that can be applied to solve particular situations. For example, what does the ST_Buffer function, how boolean predicates like ST_Contains check spatial relation of two geometries or what’s the difference between ST_Difference and ST_SymDifference.
Clearly, I’ve got way way more than I asked for or I expected. On behalf of myself and users who are about to start their adventure with PostGIS, I’d like to give big kudos to Kevin for this fantastic work!
Together with the recently documented PostgreSQL PostGIS Types and Function Support Matrix, PostGIS team is making abrupt manual a pleasant reading book.
By the way, here is a bunch of references about DE-9IM I found very useful myself:
I’d like to announce that Frank Warmerdam, one of the noble characters of the Free and Open Source Software community has joined the Planet OSGeo. Frank’s Geo-Geeking blog is available at http://fwarmerdam.blogspot.com.
Welcome Frank!
You are currently browsing the Mateusz Loskot blog archives for December, 2009.
