Archive for the pictures Category

Russell Maliphant Company

Posted in Kids, pictures with tags , , , , on May 24, 2017 by xi'an

Last weekend, the Russell Maliphant Company from London was performing in a theatre nearby (in our backyard!) and we managed to get tickets at the last minute. While I am not at all versed in modern dance, this was a fantastic experience, with very moving performances from (guest) dancers like Lucia Lacarra and Marlon Dino above, a very elaborate impact of lighting that managed to duplicate or cancel depth, space, and time, great musical tracks, and a unique quality in the movements of the dancers.

end of a long era [1982-2017]

Posted in Books, pictures, Running, University life with tags , , , , , , , , , , , on May 23, 2017 by xi'an

This afternoon I went to CREST to empty my office there from books and a few papers (like the original manuscript version of Monte Carlo Statistical Methods). This is because the research centre, along with the ENSAE graduate school (my Alma mater), is moving to a new building on the Saclay plateau, next to École Polytechnique. As part of this ambitious migration of engineering schools from downtown Paris to a brand new campus there. Without getting sentimental about this move, it means leaving the INSEE building in Malakoff, on the outskirts of downtown Paris, which has been an enjoyable part of my student and then academic life from 1982 till now. And also leaving the INSEE Paris Club runners! (I am quite uncertain about being as active at the new location, if only because going there by bike is a bit more of a challenge. To be addressed anyway!) And I left behind my accumulation of conference badges (although I should try to recycle them for the incoming BNP 11 in Paris!).

Bacon in the Library [jatp]

Posted in Books, Kids, pictures, Travel, University life with tags , , , , , , , on May 23, 2017 by xi'an

The Riddle of the Sands [not a book review]

Posted in Books, Kids, pictures, Travel with tags , , , , , on May 22, 2017 by xi'an

Visiting Dublin last weekend led me to learn of the sad end of the author of The Riddle of the Sands, (Robert) Erskine Childers.  To my surprise, I indeed found out when reading about the Irish Civil War of the early 20’s that he was executed by a firing squad as a member of the anti-Treaty Sinn Féin. What could have led the author of the role model of classical spy novels, The Riddle of the Sands, to this tragical ending?! While his book was immensely popular in Britain, to the point of impacting the preparations for war in the years before WWI, and while he served as instructor of pilots towards a possible attack of Germany through the very Frisian islands appearing in the novel, he turned progressively towards Irish nationalism, smuggling weapons on his own boat, and opposing the treaty with Britain to  the point of joining the anti-treaty Sinn Féin. When a pistol was found at his home, he was sentenced to death and executed two days later.

Rundlestone Session

Posted in Mountains, pictures, Travel, Wines with tags , , , , , , , , , on May 20, 2017 by xi'an

art brut

Posted in Mountains, pictures, Running, Travel with tags , , , , , , , on May 20, 2017 by xi'an

continental divide

Posted in Books, Kids, pictures, R with tags , , , , on May 19, 2017 by xi'an

While the Riddler puzzle this week was anticlimactic,  as it meant filling all digits in the above division towards a null remainder, it came as an interesting illustration of how different division is taught in the US versus France: when I saw the picture above, I had to go and check an American primary school on-line introduction to division, since the way I was taught in France is something like that

with the solution being that 12128316 = 124 x 97809… Solved by a dumb R exploration of all constraints:

for (y in 111:143)
for (z4 in 8:9)
for (oz in 0:999){
  z=oz+7e3+z4*1e4
  x=y*z
  digx=digits(x)
  digz=digits(z)
  if ((digz[2]==0)&(x>=1e7)&(x<1e8)){ 
   r1=trunc(x/1e4)-digz[5]*y 
   if ((digz[5]*y>=1e3)&(digz[4]*y<1e4) &(r1>9)&(r1<100)){ 
    r2=10*r1+digx[4]-7*y 
    if ((7*y>=1e2)&(7*y<1e3)&(r2>=1e2)&(r2<1e3)){     
     r3=10*r2+digx[3]-digz[3]*y 
     if ((digz[3]*y>=1e2)&(digz[3]*y<1e3)&(r3>9)&(r3<1e2)){
       r4=10*r3+digx[2]
       if (r4<y) solz=rbind(solz,c(y,z,x))
  }}}}

Looking for a computer-free resolution, the constraints on z exhibited by the picture are that (a) the second digit is 0 and the fourth digit is 7.  Moreover, the first and fifth digits are larger than 7 since y times these digits is a four-digit number. Better, since the second subtraction from a three-digit number by 7y returns a three-digit number and the third subtraction from a four-digit number by ny returns a two-digit number, n is larger than 7 but less than the first and fifth digits. Ergo, z is necessarily 97809! Furthermore, 8y<10³ and 9y≥10³, which means 111<y<125. Plus the constraint that 1000-8y≤99 implies y≥112. Nothing gained there! This leaves 12 values of y to study, unless there is another restriction I missed…