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: [email protected]
[mailto:[email protected]] 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: [email protected]
> [mailto:[email protected]] 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: [email protected]
>> [mailto:[email protected]] 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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