[Jprogramming] Turkey Roll - Challenge 2

[Henry Rich]

If you are OK with @: , then we agree.  @ is hard for beginners.


u at v  is equivalent to   u@:v"v   or  ([: u v)"v

u at v@w is u@:v"v@:w"w  or  ([:   ([: u v)"v   w)"w

Let us use   [: u v    or  u@:v  as we like, and specify a rank when we 
need one.

Henry Rich

On 12/5/2011 9:57 PM, Linda Alvord wrote:
> Can you make a simple example that looks like this  u at 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-bounces at jsoftware.com
> [mailto:programming-bounces at 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 at v is anything other than 'right to left'.  It
> means do v, then do u.  u at 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-bounces at jsoftware.com
>> [mailto:programming-bounces at 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.
>>
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