Gerard Langlet

[Stu]

Is anyone out there interested in the work of Gerard Langlet? He was well known in APL circles in the 1980's and 90's. I've recently discovered that his use of not-equals scan has some potential use in cryptography. His published works in English are available on the VECTOR archive. The ones in French are harder to come by.

[Bob Armstrong]

I consider Gerard's work one of the purest examples of APL as a Tool of Thought . It was a path impossible without the boolean operations across vectors which simply "fell out" of Ken's factoring and generalization of algebraic operators to arbitrary functions . The http://www.cosy.com/ Pub party at APL 97 in Toronto was dedicated to him .
http://www.cosy.com/cal97/apl97ad.htm

      p transpose ( 3 reshape 2 ) represent count 2 * 3 |>|
       O ' ne \' CATR P LST ' |>|' CATR FMT ne \ T |>|
 ne \ 0 0 0  |>| 0 0 0
 ne \ 0 0 1  |>| 0 0 1
 ne \ 0 1 0  |>| 0 1 1
 ne \ 0 1 1  |>| 0 1 0
 ne \ 1 0 0  |>| 1 1 1
 ne \ 1 0 1  |>| 1 1 0
 ne \ 1 1 0  |>| 1 0 0
 ne \ 1 1 1  |>| 1 0 1

( For old timers , my Casio QV10 CGA images of APL87 are at http://www.cosy.com/language/apl97/LDimages.htm )