To Raul:
> I have no idea what "works reasonably well" means.
That is a very subjective statement, apparently one can make use of
(@) and (@:) within the scope of (d.) but, of course, that depends on
one's point of view.
> But consider also:
>
> AT=: 2 :0
> u@v"v
> )
>
> +:AT*: d. 1
> 0 4x&p."0 0 0
> +:@*: d. 1
> 0 4x&p.
This also happens for (at) and I was trying to point it out this
difference in my first message:
"
> Rather works almost exactly?
>
> ('*'"_) @ ((+: @ *:) (d.1)) (0 1 2)
> *
> ('*'"_) @ ((+: at *:) (d.1)) (0 1 2)
> ***
>
> ((+: @ *:) (d.1)) b.0
> _ _ _
> ((+: at *:) (d.1)) b.0
> 0 0 0
"
However, (d.) also treats differently (at) and (AT)! (See below.)
>
> In both cases the rank of the left argument of d. is the same. So
> what we see here is that the rank of the result of d. depends on
> something other than the rank of its arguments. Have you found any
> documentation that describes the rank of the results of the d.
> conjunction?
No, hence the words "seems arbitrary” in
> and (@:) works reasonably well, although the rank change from 0 to _
> seems arbitrary, but it stumbles for (at) and ([:),
To Linda:
> Jose, I'm working on your plot program and I found a ray of hope...
Raul's (AT), unlike (at), does the job of plotting the functions:
plot @: (] ; |: @: ((u AT v) d. _2 _1 0 1 2)) Y
although in a different fashion, at least for the fixed version
according to the interpreter:
plot @: (] ; |: @: ((u AT v)f. d. _2 _1 0 1 2)) Y
plot @: (] ; |: @: ((u @ v)f. d. _2 _1 0 1 2)) Y
(u AT v)f. d. _2 _1 0 1 2
(0 0 0 0 1r24&p."0 0 0 , 0 0 0 1r6&p."0 0 0 , -:@*:"0 0 0 , ["0 0 0 ,
1"0"0 0 0)"0
(u @ v)f. d. _2 _1 0 1 2
(0 0 0 0 1r24&p. , 0 0 0 1r6&p. , -:@*: , [ , 1"0)"0
Although so far it has not been confirmed, there is plenty of evidence
that (d.) attracted some bugs; Raul's (at) and ([:) do not work well
in this context but they should have worked.
It seems to me that you would like to use (2 : '([: u v)"v') instead
of (@) because the former is more clear to you. But I would like to
second Henri's advice, if you understand (2 : '([: u v)"v') then you
understand (@). Why would you like then to use a long hand, so to
speak, instead of a short hand (besides, as this thread shows, (@) is
more reliable)? Similar comments, but to lesser extent, apply to ([:)
vs. (@:).
________________________________________________________________________
On Sun, Jan 13, 2013 at 12:06 PM, Raul Miller <[email protected]> wrote:
> On Sun, Jan 13, 2013 at 10:26 AM, Linda Alvord <[email protected]>
> wrote:
>> It seems to need d."0 but I can't seem to figure how to do it.
>
> You can use "0 on the result of d. For example:
>
> (d. 1) (" 0)
>
> I do not think you should have to do this, but it works.
>
> --
> Raul
> ----------------------------------------------------------------------
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