Oh, I see what you are saying. I somehow sidetracked onto a different issue.
My apologies. Thanks, -- Raul On Mon, Feb 13, 2017 at 11:39 AM, Louis de Forcrand <[email protected]> wrote: > I'm afraid that what is happenning here is not simple. > > u=: (mp~ |:) (-"1 mean) > v=: (mp~ |:)@(-"1 mean) > > u A > A mp~ |: (-"1 mean) A > (|: A -"1 mean A) mp A > > v A > (mp~ |:) A -"1 mean A > (|: A -"1 mean A) mp A -"1 mean A > > It is not obvious that these two verbs are mathematically equivalent. That is > why my post may be hard to follow. > > Louis > >> On 13 Feb 2017, at 17:25, Raul Miller <[email protected]> wrote: >> >> Eh... ok, but that's pretty hard to follow, and there's much simpler >> ways of recognizing what's going on here. >> >> -- >> Raul >> >> >>> On Mon, Feb 13, 2017 at 10:15 AM, Louis de Forcrand <[email protected]> >>> wrote: >>> I forgot to divide by m, see my correction. >>> >>> Louis >>> >>>> On 13 Feb 2017, at 15:24, Raul Miller <[email protected]> wrote: >>>> >>>> I'm having problems following your reasoning here. >>>> >>>> Consider: >>>> >>>> A=: 5 3 $ 90 60 90 90 90 30 60 60 60 60 60 90 30 30 30 >>>> mean=: +/%# >>>> mp=: +/ . * >>>> C=: A - B=: (E=: (m,m) $ 1) mp A % m=: #A >>>> u=: ((mp~ |:) (-"1 mean)) % # >>>> v=: (mp~ |:)@(-"1 mean) % # >>>> u A >>>> 504 360 180 >>>> 360 360 0 >>>> 180 0 720 >>>> (|:C) mp A >>>> 2520 1800 900 >>>> 1800 1800 0 >>>> 900 0 3600 >>>> >>>> If I understand your presentation, those two results should have been >>>> the same. But they are not... >>>> >>>> Can you run through your work with some example values and see whether >>>> you think it's the presentation or my understanding of it that needs >>>> to change? >>>> >>>> Thanks, >>>> >>>> -- >>>> Raul >>>> >>>> >>>> >>>>> On Mon, Feb 13, 2017 at 6:36 AM, Louis de Forcrand <[email protected]> >>>>> wrote: >>>>> A few corrections: >>>>> >>>>> u is >>>>> (|:C) mp A % m >>>>> and v is >>>>> (|:C) mp C % m >>>>> but we can multiply both by m when showing that they are equal. >>>>> >>>>> In addition, I forgot a division by m here: >>>>>> +/ (i{Et) * j {"1 E >>>>> that should read >>>>> +/ (i{Et) * j {"1 E % m. >>>>> >>>>> Louis >>>>> >>>>>> On 13 Feb 2017, at 01:35, Louis de Forcrand <[email protected]> wrote: >>>>>> >>>>>> The two statements are executing two different procedures which happen >>>>>> to be mathematically equivalent: >>>>>> >>>>>> u=: ((mp~ |:) (-"1 mean)) % # >>>>>> v=: (mp~ |:)@(-"1 mean) % # >>>>>> >>>>>> If (u -: v) A for a matrix A, then >>>>>> (((mp~ |:) (-"1 mean)) -: (mp~ |:)@(-"1 mean)) A. >>>>>> >>>>>> Let >>>>>> C=: A - B=: (E=: (m,m) $ 1) mp A % m=: #A >>>>>> then u is >>>>>> (|:C) mp A >>>>>> and v is >>>>>> (|:C) mp C. >>>>>> >>>>>> Let's look at u: >>>>>> (|:C) mp A >>>>>> (|:A-B) mp A >>>>>> ((At=: |:A) - Bt=: |:B) mp A >>>>>> (At mp A) - Bt mp A >>>>>> >>>>>> Now for v: >>>>>> (|:C) mp C >>>>>> (At - Bt) mp A - B >>>>>> (At mp A) - (At mp B) - (Bt mp A) + Bt mp B >>>>>> >>>>>> We can see that if >>>>>> (Bt mp B) -: At mp B >>>>>> then (u -: v) A. >>>>>> >>>>>> At mp B >>>>>> At mp E mp A % m >>>>>> >>>>>> Bt mp B >>>>>> (|: E mp A % m) mp E mp A % m >>>>>> At mp (Et=: |:E) mp E mp A % *:m >>>>>> At mp (E mp E % m) mp A % m >>>>>> >>>>>> Now (and for the coup de grace): >>>>>> (<i,j) { E mp E % m >>>>>> +/ (i{Et) * j {"1 E >>>>>> +/ (m$1) * m $ 1 % m >>>>>> 1 for all i and j between 0 and m. >>>>>> Therefor >>>>>> E -: E mp E % m. >>>>>> >>>>>> And thus >>>>>> Bt mp B >>>>>> At mp E mp A % m >>>>>> At mp B >>>>>> >>>>>> (u -: v) A for all matrices A. # >>>>>> >>>>>> Cheers, >>>>>> Louis >>>>>> >>>>>> PS: I hope I didn't make and mistakes, but I might have. Thanks for >>>>>> checking! >>>>>> >>>>>>> On 12 Feb 2017, at 18:54, Raul Miller <[email protected]> wrote: >>>>>>> >>>>>>> It's not so much that it's of no use, but that it's redundant. >>>>>>> >>>>>>> When your hook is a train where the first verb is a hook, you can >>>>>>> restructure either of them so that the other of those two hooks takes >>>>>>> over the responsibility of obtaining the hook's "left argument" >>>>>>> (presumably, this would eliminate the other hook). >>>>>>> >>>>>>> I hope this helps, >>>>>>> >>>>>>> -- >>>>>>> Raul >>>>>>> >>>>>>> >>>>>>>> On Sun, Feb 12, 2017 at 10:18 AM, R.E. Boss <[email protected]> >>>>>>>> wrote: >>>>>>>> I think the problem is that the big hook is of no use, that's what >>>>>>>> creates confusion. >>>>>>>> >>>>>>>> (data mp1 mn data)% # data >>>>>>>> 504 360 180 >>>>>>>> 360 360 0 >>>>>>>> 180 0 720 >>>>>>>> >>>>>>>> data mp1 mn data >>>>>>>> 2520 1800 900 >>>>>>>> 1800 1800 0 >>>>>>>> 900 0 3600 >>>>>>>> >>>>>>>> mp1 mn data >>>>>>>> 2520 1800 900 >>>>>>>> 1800 1800 0 >>>>>>>> 900 0 3600 >>>>>>>> >>>>>>>> >>>>>>>> R.E. Boss >>>>>>>> >>>>>>>> >>>>>>>> -----Original Message----- >>>>>>>> From: Programming [mailto:[email protected]] On >>>>>>>> Behalf Of 'Mike Day' via Programming >>>>>>>> Sent: zondag 12 februari 2017 12:02 >>>>>>>> To: [email protected] >>>>>>>> Subject: Re: [Jprogramming] Hooked again >>>>>>>> >>>>>>>> It looks to me as if the two left hooks form one big left hook, not >>>>>>>> that I'm into boxing: >>>>>>>> >>>>>>>> mn =: -"1 mean >>>>>>>> mp1=: mp~|: >>>>>>>> >>>>>>>> ((mp1 mn)%#)data NB. big "hook" >>>>>>>> 504 360 180 >>>>>>>> 360 360 0 >>>>>>>> 180 0 720 >>>>>>>> >>>>>>>> ((mp1 @: mn)%#)data NB. mp1 after mn using @: >>>>>>>> 504 360 180 >>>>>>>> 360 360 0 >>>>>>>> 180 0 720 >>>>>>>> >>>>>>>> (([: mp1 mn)%#)data NB. mp1 after mn using [: >>>>>>>> 504 360 180 >>>>>>>> 360 360 0 >>>>>>>> 180 0 720 >>>>>>>> >>>>>>>> Any use? >>>>>>>> >>>>>>>> Mike >>>>>>>> >>>>>>>> >>>>>>>>> On 12/02/2017 08:06, Lippu Esa wrote: >>>>>>>>> ]data=. 5 3 $ 90 60 90 90 90 30 60 60 60 60 60 90 30 30 30 >>>>>>>>> >>>>>>>>> mean=: +/%# >>>>>>>>> mp=: +/ . * >>>>>>>>> covmat=: ((mp~|:)(-"1 mean))%# NB. divede by n not n-1 to comply with >>>>>>>>> the example >>>>>>>> >>>>>>>> >>>>>>>> --- >>>>>>>> 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 >>>>>> >>>>>> ---------------------------------------------------------------------- >>>>>> 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 ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
