([: u v)"v y is u@v .
For & you have
x u&:v y <=> (v x) u (v y) <=> x (v@[ u v@]) y
and
u&v <=> u&:v"mv where mv is ({. v b. 0)
You are making your understanding very difficult - in fact, perhaps
impossible - by trying to do everything wuth [: . @, @:, &, &: are all
different. If [: were all you needed, maybe Ken would have left out the
others.
Henry Rich
On 1/12/2013 8:50 PM, Linda Alvord wrote:
Thanks David, Kip and Rich
My concern is that it is too hard to find the alternative when the simple
definition doesn't work.
u&v y -> ([: u v)"v y
As long as the ranks agree, u&v y -> u v y
Would this be useful as a definition of compose?
Linda
-----Original Message-----
From: programming-boun...@forums.jsoftware.com
[mailto:programming-boun...@forums.jsoftware.com] On Behalf Of Henry Rich
Sent: Saturday, January 12, 2013 8:17 PM
To: programm...@jsoftware.com
Subject: Re: [Jprogramming] joining to an empty list
What he's saying (& Kip earlier) is, when you wrote
([: u v y)"v
you meant
([: u v)"v y
because
([: u v y)
gives a domain error.
Henry Rich
On 1/12/2013 7:48 PM, Linda Alvord wrote:
David, I don't understand the concern you are raising
u&v y -> ([: u v y)"v
As long as the ranks agree, u&v y -> u v y
]A=:'one';'two';'three'
----T---T-----┐
│one│two│three│
L---+---+------
#&>A
3 3 5
([:#>)">A
3 3 5
In this case there is no domain error. Is there a different context
when you will get a domain error?
Thanks in advance:Linda
-----Original Message-----
From: programming-boun...@forums.jsoftware.com
[mailto:programming-boun...@forums.jsoftware.com] On Behalf Of David
Ward Lambert
Sent: Saturday, January 12, 2013 3:43 PM
To: programming
Subject: Re: [Jprogramming] joining to an empty list
The vocabulary should not say
u&v y -> ([: u v y)"v
because
[: verb verb NOUN
is a domain error.
----------------------
Subject: Re: [Jprogramming] joining to an empty list
Message-ID: <000e01cdf0d4$4d3da130$e7b8e390$@net>
Content-Type: text/plain; charset=utf-8
Here's a sentence that I think would be more helpful in the vocabulary:
]A=:'one';'two';'three'
???????????????
?one?two?three?
???????????????
#&>A
3 3 5
([:#>)">A
3 3 5
^
NB. Then shouldn't the vocabulary say u&v y -> ([: u v y)"v
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