Have I missed an update, then? Thanks, Mike Sent from my iPad
> On 21 Feb 2019, at 16:58, Henry Rich <[email protected]> wrote: > > The crash should be fixed in the latest released version, but I haven't > verified that. > > Henry Rich > > On Thu, Feb 21, 2019, 5:40 AM 'Mike Day' via Programming < > [email protected]> wrote: > >> Back to this thread... >> >> I've worked up an explicit variant, sig3, using I. and E. - fairly >> simple-minded, >> >> but might be of interest. Also revisiting sig1 for comparison. sig3 is >> not so good for >> >> space, but is reasonably fast for the example. >> >> NB. minmd =: (({.@:/:~)`(<./)@.(0-:{.@:(0&{.))) >> minmd =: {.@:/:~ NB. this works for strings as well as numeric arrays >> sig1 =: {.@(/:~)@:(|."0 1~) (I.@:= minmd) >> >> NB. rotate each occurrence of minimum pair to front >> sig2 =: 13 : '{./:~ y |."0 1~ i#~ (=minmd) y {~ <: i =. I. y = minmd y' >> >> sig3 =: 3 : 0 >> b =. (,.~) y >> NB. following replaces values by characters - assuming nub is small enough! >> NB. but it doesn't appear to save space! >> NB. b =. (,.~) ((~.@:,) (a.{~i.) ]) y >> 'm n' =. $y >> bool =. m#1 >> for_pad. }.i.<: m do. >> 'a b' =. ({.;}.) b >> if. bool{~<:pad do. >> if. +/ i =. (n {.a) (+/@:E.)"1 b do. >> bool =. 0 (pad + I.i) } bool >> end. >> end. >> end. >> bool >> ) >> >> ts'~:sigb a' >> >> 0.000348269 6656 >> >> ts'~:sigi a' >> >> 0.000235419 6272 >> >> ts'~:sig3 a' >> >> 0.000233799 13248 >> >> ts'~:sig1"1 a' >> >> 0.000106371 7680 >> >> >> Also, I can confirm that Henry's canonical shift crashes this version of >> Jqt >> >> JVERSION >> Engine: j807/j64/windows >> Release-b: commercial/2019-01-22T18:51:16 >> Library: 8.07.22 >> Qt IDE: 1.7.9/5.9.6 >> Platform: Win 64 >> Installer: J807 install >> InstallPath: c:/d/j807 >> Contact: www.jsoftware.com >> >> Cheers, >> >> Mike >> >> >> >>> On 16/02/2019 17:52, [email protected] wrote: >>> I rewrote two explicit and perhaps clearer versions of my sig verb. Both >> work on the same principle as the original, but one uses a bit vector and >> the other uses a list of indices, and the indices are a bit faster (pun >> probably intended). I prefer the bit vector aesthetically though. >>> >>> Both basically store the set of indices where possible lexicographically >> minimal rotations could start (b and i in the verbs). On iteration n, the >> starting index of rotations whose nth element is not minimal among the nth >> elements of all possibly minimal rotations are removed from the >> aforementioned set. The iteration continues until only one possible >> rotation is left, and for a maximum of #y times, in which case all elements >> of y are identical and so any rotation will do. >>> >>> If I am not mistaken (I might be, have to hurry and go now), since there >> are a maximum of #y iterations and each includes at most #y comparisons (= >> <./), the number of comparisons is at worst quadratic in the length of y. >> This happens when 1=#~.y, but most of the time this number is much smaller. >>> >>> sigb=: (|.~ 3 : 0)"1 >>> b=. 1"0 y >>> for. y do. >>> if. 1 = +/b do. break. end. >>> b=. (= <./)&.(b&#) y >>> y=. 1|.y >>> end. >>> b i. 1 >>> ) >>> >>> sigi=: (|.~ 3 : 0)"1 >>> i=. i.#y >>> for. y do. >>> if. 1 = #i do. break. end. >>> i=. i ((= <./)@:{ # [) y >>> y=. 1|.y >>> end. >>> i >>> ) >>> >>> Cheers, >>> Louis >>> ---------------------------------------------------------------------- >>> For information about J forums see http://www.jsoftware.com/forums.htm >> >> >> --- >> This email has been checked for viruses by Avast antivirus software. >> https://www.avast.com/antivirus >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
