This is not an example where rank is not appropriate. Rank does matter. It is interesting as a problem and I need to think about it as a mathematical problem. From a programming point of view here's the issue: ^@o.@j. 0 0.5 1 1.5 1 0j1 _1 0j_1 d=:0 0.5 1 1.5 j.d 0 0j0.5 0j1 0j1.5 o.j.d 0 0j1.5708 0j3.14159 0j4.71239 ^[:o.j.d ^[:o.j.d |domain error | ^ [:o.j.d ^@o.j.d 1 6.12323e_17j1 _1j1.22465e_16 _1.83697e_16j_1 ^@:o.j.d 1 6.12323e_17j1 _1j1.22465e_16 _1.83697e_16j_1
If you adopt my rule, then @: is really needed here and @ could be eliminated. I haven't looked at the other two examples yet. Linda 2011/12/6 Linda Alvord <lindaalv...@verizon.net> > Can you make a simple example that looks like this u@v@w ? Please use > actual verbs so that it is a tight little nugget that might come about in a > fairly simple mathematical situation. Use it in a situation that does not > require rank. Next, write it in explicit form without @ > > Here's what I would like. Remember foo ? > > foo=: 13 :'an expression with x's and y's and three verbs like # , %: , > ? or * ' > > > Also: > > Let us use [: u v or u@:v as we like, and specify a rank when we > need one. > > I think I could live with: > > Let us use [: u v unless rank is involved. Only use u@:v if rank is > needed, thus @ vanishes from the planet. > > > Linda > > > -----Original Message----- > From: programming-boun...@jsoftware.com > [mailto:programming-boun...@jsoftware.com] On Behalf Of Henry Rich > Sent: Monday, December 05, 2011 10:08 PM > To: Programming forum > Subject: Re: [Jprogramming] Turkey Roll - Challenge 2 > > If you are OK with @: , then we agree. @ is hard for beginners. > > > u@v is equivalent to u@:v"v or ([: u v)"v > > u@v@w is u@:v"v@:w"w or ([: ([: u v)"v w)"w > > Henry Rich > > On 12/5/2011 9:57 PM, Linda Alvord wrote: > > Can you make a simple example that looks like this u@v@w . Is it > possible > > to write an explicit version that will create a tacit expression to do > the > > same thing? > > > > I don't have a problem with @: . My concern is only with @ > > > > Linda > > > > -----Original Message----- > > From: programming-boun...@jsoftware.com > > [mailto:programming-boun...@jsoftware.com] On Behalf Of Henry Rich > > Sent: Monday, December 05, 2011 9:28 PM > > To: Programming forum > > Subject: Re: [Jprogramming] Turkey Roll - Challenge 2 > > > > I don't understand why u@v is anything other than 'right to left'. It > > means do v, then do u. u@v@w means w, then v, then u. > > > > The complication of @ is not its ordering, it's its rank. In my classes > > I teach @: as a primitive. We don't use [:, or @ . > > > > Henry Rich > > > > On 12/5/2011 9:15 PM, Linda Alvord wrote: > >> > >> Compare your expression for dice : > >> > >> faces=: {&' o'@((i.3 3)e.&":"1])&.>4 80 840 8620 86420 865320 > >> faces > >> ------T-----T-----T-----T-----T-----┐ > >> │ │o │o │o o│o o│o o│ > >> │ o │ │ o │ │ o │o o│ > >> │ │ o│ o│o o│o o│o o│ > >> L-----+-----+-----+-----+-----+------ > >> > >> With Kip Murray's version: > >> > >> one =: ' ',' o ',:' ' > >> two =: 'o ',' ',:' o' > >> three =: 'o ',' o ',:' o' > >> four =: 'o o',' ',:'o o' > >> five =: 'o o',' o ',:'o o' > >> six =: 'o o','o o',:'o o' > >> ]dice =: one;two;three;four;five;six > >> ----T---T---T---T---T---┐ > >> │ │o │o │o o│o o│o o│ > >> │ o │ │ o │ │ o │o o│ > >> │ │ o│ o│o o│o o│o o│ > >> L---+---+---+---+---+---- > >> > >> Your dice are great looking! However that change has greatly increased > the > >> complexity of the code. Also, there is a condition of the challenge to > >> exclude @ in each expression. This requirement encourages considering > > the > >> execution from the right toward the left. In your example 4 80 840 > 8620 > >> 86420 865320 could be puzzling to a beginner. Your other ideas are > >> thoughtful ideas to incorporate in an actual design of a program. At > this > >> stage, I'm trying to raise issues that can be discussed and explored > >> further. > >> > >> From your design so far, is it possible for you to capture the actual > > values > >> of the and display them following each toss ? It is this data that > > will > >> be useful as you finish the challenge. > >> > >> Linda > >> > >> > >> -----Original Message----- > >> From: programming-boun...@jsoftware.com > >> [mailto:programming-boun...@jsoftware.com] On Behalf Of Raul Miller > >> Sent: Monday, December 05, 2011 9:50 AM > >> To: Programming forum > >> Subject: Re: [Jprogramming] Turkey Roll - Challenge 2 > >> > >> Personally, I have been baffled by a number of the choices and > > requirements > >> here. And, by this, I mean that I do not understand them. > >> > >> That said, here is my current interpretation of a mix of some of the > >> statements expressed here, about what is being accomplished: > >> > >> faces=: {&' o'@((i.3 3)e.&":"1])&.>4 80 840 8620 86420 865320 > >> toss=: (] {~ (?@$ #)) ".bind 'faces' > >> > >> Example use, with ascii box drawing enabled: > >> > >> toss 2 10 > >> +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ > >> |o |o |o o|o |o |o |o |o o|o o|o o| > >> | o | o | o | o | o | | | | o |o o| > >> | o| o|o o| o| o| o| o|o o|o o|o o| > >> +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ > >> |o |o o|o |o o|o o|o |o |o |o o|o | > >> | o | o | | o | | | | | | | > >> | o|o o| o|o o|o o| o| o| o|o o| o| > >> +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ > >> toss 2 10 > >> +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ > >> |o |o |o o|o |o o|o |o o|o o|o o|o | > >> | | | | o |o o| o | | o |o o| | > >> | o| o|o o| o|o o| o|o o|o o|o o| o| > >> +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ > >> |o o|o |o o|o o|o o|o o| |o o|o o|o o| > >> | | | o | | | o | o | | | | > >> |o o| o|o o|o o|o o|o o| |o o|o o|o o| > >> +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ > >> > >> Notes: > >> > >> 1. I spaced my pips out wider, horizontally, than the original. I think > >> this looks better. > >> 2. toss has 'faces' as an implicit dependency > >> 3. I can change the number of dice being tossed by changing the argument > > to > >> toss > >> > >> In my opinion, this is not a very good design. In "real life" code, I > >> would either replace (". bind 'faces') with (faces) or I would make it > an > >> argument to the function. > >> > >> I could probably compress a few characters out of the definition of > faces, > >> but it would become more mysterious if I did so. > >> > > ---------------------------------------------------------------------- > > 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
