I thought that J did not represent negative zero? Is it possible to trick J into revealing a negative zero? If so, does it involve foreigns or is there some native calculations that lead here?
Thanks, -- Raul On Wed, Jan 16, 2013 at 7:26 AM, Henry Rich <henryhr...@nc.rr.com> wrote: > On my awaking, there was a whiff of sulfur in the air, and a greenish > haze... and somehow in my mind the idea that that last program won't work, > because of the possibility of negative zero. I'll stay relegated to imp > status. > > Henry Rich > > > On 1/15/2013 6:20 PM, Henry Rich wrote: >> >> Nah, that's not beyond impish. The devilish solution is to take the >> bitwise OR of the matrix with its conjugate transpose (but that's easier >> in assembler language than in J: >> (23 b.&.(a.&i.)&.(2&(3!:5))&.+. +@|:)) >> ). And you need to be sure that the zeros on the lower diagonal and >> below are true zeros! >> >> Henry Rich >> >> On 1/15/2013 6:03 PM, km wrote: >>> >>> Oh, boy! (v1`v2) } y <--> (v1 y) } (v2 y) >>> >>> Brief and devilish, take care for your soul, Henry! >>> >>> --Kip >>> >>> Sent from my iPad >>> >>> >>> On Jan 15, 2013, at 3:39 PM, Henry Rich <henryhr...@nc.rr.com> wrote: >>> >>>> hft =: 0&=`(,: +@|:)} >>>> >>>> Henry Rich >>>> >>>> On 1/15/2013 5:25 AM, km wrote: >>>>> >>>>> This is an easy one. A Hermitian matrix matches its conjugate >>>>> transpose. Write a verb hft that creates a Hermitian matrix from a >>>>> triangular one that has a real diagonal. >>>>> >>>>> ishermitian =: -: +@|: >>>>> ]A =: 2 2 $ 1 2j3 0 4 >>>>> 1 2j3 >>>>> 0 4 >>>>> ]B =: hft A >>>>> 1 2j3 >>>>> 2j_3 4 >>>>> ishermitian A >>>>> 0 >>>>> ishermitian B >>>>> 1 >>>>> >>>>> Kip Murray >>>>> >>>>> Sent from my iPad >>>>> ---------------------------------------------------------------------- >>>>> 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 >>> >> ---------------------------------------------------------------------- >> 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
