Archive for laptop

web [mis-]content

Posted in Statistics with tags , , , on March 7, 2017 by xi'an

For the past two weeks, I have noticed a web content process on my computer, process that eats a lot of my CPU! And I have not found any final solution when looking on Linux/Ubuntu fora/forums… Moving to a new [and neat] laptop [as the older one broke an hinge that could not be fixed!] did not help, while killing the process by itself saw this very tab vanish on Firefox and the process reappear a few seconds later. Solving this issue seems beyond my reach!

Extending R

Posted in Books, Kids, R, Statistics with tags , , , , , , , , , , , , , , , , , on July 13, 2016 by xi'an

As I was previously unaware of this book coming up, my surprise and excitement were both extreme when I received it from CRC Press a few weeks ago! John Chambers, one of the fathers of S, precursor of R, had just published a book about extending R. It covers some reflections of the author on programming and the story of R (Parts 2 and 1),  and then focus on object-oriented programming (Part 3) and the interfaces from R to other languages (Part 4). While this is “only” a programming book, and thus not strictly appealing to statisticians, reading one of the original actors’ thoughts on the past, present, and future of R is simply fantastic!!! And John Chambers is definitely not calling to simply start over and build something better, as Ross Ihaka did in this [most read] post a few years ago. (It is also great to see the names of friends appearing at times, like Julie, Luke, and Duncan!)

“I wrote most of the original software for S3 methods, which were useful for their application, in the early 1990s.”

In the (hi)story part, Chambers delves into the details of the evolution of S at Bells Labs, as described in his [first]  “blue book” (which I kept on my shelf until very recently, next to the “white book“!) and of the occurrence of R in the mid-1990s. I find those sections fascinating maybe the more because I am somewhat of a contemporary, having first learned Fortran (and Pascal) in the mid-1980’s, before moving in the early 1990s to C (that I mostly coded as translated Pascal!), S-plus and eventually R, in conjunction with a (forced) migration from Unix to Linux, as my local computer managers abandoned Unix and mainframe in favour of some virtual Windows machines. And as I started running R on laptops with the help of friends more skilled than I (again keeping some of the early R manuals on my shelf until recently). Maybe one of the most surprising things about those reminiscences is that the very first version of R was dated Feb 29, 2000! Not because of Feb 29, 2000 (which, as Chambers points out, is the first use of the third-order correction to the Gregorian calendar, although I would have thought 1600 was the first one), but because I would have thought it appeared earlier, in conjunction with my first Linux laptop, but this memory is alas getting too vague!

As indicated above, the book is mostly about programming, which means in my case that some sections are definitely beyond my reach! For instance, reading “the onus is on the person writing the calling function to avoid using a reference object as the argument to an existing function that expects a named list” is not immediately clear… Nonetheless, most sections are readable [at my level] and enlightening about the mottoes “everything that exists is an object” and “everything that happens is a function” repeated throughout.  (And about my psycho-rigid ways of translating Pascal into every other language!) I obviously learned about new commands and notions, like the difference between

x <- 3

and

x <<- 3

(but I was disappointed to learn that the number of <‘s was not related with the depth or height of the allocation!) In particular, I found the part about replacement fascinating, explaining how a command like

diag(x)[i] = 3

could modify x directly. (While definitely worth reading, the chapter on R packages could have benefited from more details. But as Chambers points out there are whole books about this.) Overall, I am afraid the book will not improve my (limited) way of programming in R but I definitely recommend it to anyone even moderately skilled in the language.

an hectic trip!

Posted in Running, Statistics, Travel, University life with tags , , , , , , , on February 22, 2013 by xi'an

Elben, Hamburg, Feb. 21, 2013The trip to Hamburg had started inauspiciously: a heart attack (someone else’s heart) in the métro (RER) has frozen the train traffic completely on Tuesday and I was lucky to find a taxi that managed to drive me to the airport in the nick of time. As there were warnings of strike in the Hamburg airport today, I decided to pack early and left DESY long enough in advance to reach the aiport by public transportation: it is only once I cleared security and sat at the gate that I realised I had forgotten my PC power box/cord in my room at DESY. What a drag! Anyway, I managed to buy a universal adapter in Paris on my way back from the airport and still to attend Adam Johansen’s seminar on Rao-Blackwellisation of particle filters at the Big’MC seminar. An interesting exploitation of missing variable structures within missing variables in a hidden Markov chain! (I missed the reason for the O(NM) computing time, though.) On the way home, I reflected on how little I had seen of Hamburg: a nice train system, a green and pleasant suburban area south of DESY towards the Elben (Groß Flottbeck), while running this morning, and…the airport! I wish I had had the opportunity and the time to get a glimpse of downtown Hamburg.