A follow up, its pretty easy to add other parameters to the function:
'(T2|.(<T1)= ] ) T0@]^:[each]' evalTP ('3&*';'2') evalTP '2' ;/ 1 2 3 2 2 4
2
┌─┬─┬─┬─┬─┬─┬─┐
│1│6│9│2│6│4│6│
└─┴─┴─┴─┴─┴─┴─┘
turns the resulting verb into tripling the item 2 cells previous when one cell
is 2
'(T2|.(<T1)= ] ) T0@]^:[each]' evalTP ('3&*';'2')
( T0 |. ( < 2 ) = ] ) 3&* @ ] ^: [ each ]
----- Original Message -----
From: 'Pascal Jasmin' via Programming <[email protected]>
To: "[email protected]" <[email protected]>
Cc:
Sent: Sunday, May 18, 2014 12:16:46 PM
Subject: Re: [Jprogramming] ^: and boxes
yes. sorry I didn't bother fixing the 2nd example:
one fix:
((1|.(<2)=]) +:@]^:[each]) scalarize@:tonumifnum each cut '1 2 3 2 2 4 2 a
1'
┌─┬─┬─┬─┬─┬─┬─┬─┬─┐
│2│2│6│4│2│8│2│a│1│
└─┴─┴─┴─┴─┴─┴─┴─┴─┘
where:
tonumifnum =: 0&".^:(1&". -: 0&".)
scalarize =: {.^: ((,1) -: $)
Here is another interesting approach to solving the problem with a template
approach:
I've shown this conjunction before:
evalT =: 2 : 0
NB. strip unused Ts (optional)
n =. boxopen n
pD imax =: <: # n NB. =. v"_ y
m =. ]`(''"_)@.(imax< 0 ". }.)^:('T'={.) each ;: m
for_i. n do. m =. i (I. m = <'T',": i_index) } m end.
(;: inv m) eval
)
eval =: 1 : ' a: 1 : m'
A conjunction that substitutes into template m, parameters from n. Though this
can already mostly be done through @. tricks, this is probably much more
readable, and easy to write: Here the verb is parametarized for double (+:)
when following cell is 2
'(1|.(<T1)= ] ) T0@]^:[each]' evalT ('+:';'2')
(1 |. (<2) = ]) +:@]^:[&.> ]
Its producing a tacit verb:
'(1|.(<T1)= ] ) T0@]^:[each]' evalT ('+:';'2') (<'a') ,~ ;/ 1 2 3 2 2 4
2
┌─┬─┬─┬─┬─┬─┬─┬─┐
│2│2│6│4│2│8│2│a│
└─┴─┴─┴─┴─┴─┴─┴─┘
I can improve this to provide partial substitutions with this conjunction:
evalTP =: 2 : 0
n =. boxopen n
c=. i.0
for_i. n do. c=. c, ('T' , [: ": i_index"_)^:(0=# ) each i end. n=. c
imax =: <: # n NB. =. v"_ y
m =. ;: m
for_i. n do. m =. i (I. m = <'T',": i_index) } m end.
m =.('T', [: ": (>: imax) -~ 0 ". }.)^:(imax< 0 ". }.)^:('T'={.) each m
if. -. (<'T0') e. m do. (;: inv m) eval else. ;: inv m end.
)
This allows for partial substitutions, and then returns the completed verb when
no more substitutions are available:
'(1|.(<T1)= ] ) T0@]^:[each]' evalTP ('+:') evalTP ('2')
(1 |. (<2) = ]) +:@]^:[&.> ] NB.tacit completed verb
'(1|.(<T1)= ] ) T0@]^:[each]' evalTP ('+:')
( 1 |. ( < T0 ) = ] ) +: @ ] ^: [ each ] NB. string (template) with T0
replacing T1 parameter
'(1|.(<T1)= ] ) T0@]^:[each]' evalTP ('';'2')
( 1 |. ( < 2 ) = ] ) T0 @ ] ^: [ each ] NB. string (template) with binding
of T1 parameter but not T0
'(1|.(<T1)= ] ) T0@]^:[each]' evalTP ('+:';'2') (<'a') ,~ ;/ 1 2 3 2 2 4
2
┌─┬─┬─┬─┬─┬─┬─┬─┐
│2│2│6│4│2│8│2│a│
└─┴─┴─┴─┴─┴─┴─┴─┘
The last example shows binding all parameters such as evalT. (evalT has
different behaviour that deletes template items if not passed)
----- Original Message -----
From: greg heil <[email protected]>
To: Programming forum <[email protected]>
Cc:
Sent: Sunday, May 18, 2014 11:48:47 AM
Subject: Re: [Jprogramming] ^: and boxes
Pascal
>The difficulty is your examples are contradictory. The number 2 is different
>from the letter 2.
>Perhaps a gold standard of the test case is needed eg
d2=: <2
or
d2=: <,2
or
d2=: <,'2'
or it might be a set...
greg
~krsnadas.org
--
from: 'Pascal Jasmin' via Programming <[email protected]>
to: "[email protected]" <[email protected]>
date: 18 May 2014 06:56
subject: Re: [Jprogramming] ^: and boxes
That is a cool way of getting doubles:
([: >: (<2) = 1 |. ]) ;/ 1 2 3 2 2 4 2 1
2 1 2 2 1 2 1 1
>I thank you for the creative approach, while still following all the
>directions. I learned something from all of the creative approaches provided.
> I was most interested in a good way to modify boxed data cells based on the
>content of other cells. I understand how people are helpfully trying to solve
>the problem they want to solve instead of magically reading my intent. When
>presenting the problem I prefer that there be a final unboxed presentation for
>display purposes, and I also prefer the simplest possible data argument, but
>it makes deciphering my intent more difficult.
>Here is a solution/problem statement that makes the boxed input requirement
>more than just an inconvenience. Perhaps if I put white space between the
>verb and data, its clear that the solution being sought should only modify the
>left of the white space:
((1|.(<2)=]each) +:@]^:[each ]) (<'a') ,~ ;/ 1 2 3 2 2 4 2
+---------------+
¦2¦2¦6¦4¦2¦8¦2¦a¦
+---------------+
>Though that example invites solutions that remove the tail then add it back
>later :P. So, perhaps I should provide 2 sample inputs:
((1|.(<2)=]each) +:@]^:[each ]) cut '1 2 3 2 2 4 2 a 1'
+-----------------+
¦1¦2¦3¦2¦2¦4¦2¦a¦1¦
+-----------------+
--
From: Joe Bogner <[email protected]>
To: [email protected]
Sent: Sunday, May 18, 2014 8:04:08 AM
Subject: Re: [Jprogramming] ^: and boxes
>I would probably do this. Boxing is based on original requirement of right
>side being boxed
(> * [: >: (<2) = 1 |. ]) ;/ 1 2 3 2 2 4 2 1
2 2 6 4 2 8 2 1
Works on the negative test too
(> * [: >: (<2) = 1 |. ]) ;/ _1 2 _3 2 2 _4 2 _1
_2 2 _6 4 2 _8 2 _1
>It doesn't use ^: , which was in the subject line and may not be valid if ^:
>is required
--
from: greg heil <[email protected]>
to: Programming forum <[email protected]>
date: 17 May 2014 08:28
subject: Re: [Jprogramming] ^: and boxes
Linda
>Wow that is super understandable and compact! Of course its domain is limited,
>Eg it does not like negative numbers:
d=: 1 2 3 2 2 4 2 1
dn=: _1 2 _3 2 2 _4 2 _1
dn=: (]* _1&^ @ (2~:])) d
fLA=: ] >. +: * 1 |. 2 = ]
fLA dn
_1 2 _3 4 2 _4 2 0
>It did take me a _long_ time to penetrate Aai`s sophistry! Finally the key was
>that /. was really oblique, not key! ...but it does survive this negative
>number test:
fA=: [: }. 2&*//.@(2&=,:])
fA dn
_2 2 _6 4 2 _8 2 _1
>Anyway i think i am awake this am, thanks! i could be fooled though, only
>dreaming i was awake;)
greg
~krsnadas.org
--
from: Linda Alvord <[email protected]>
to: [email protected]
date: 16 May 2014 21:51
subject: Re: [Jprogramming] ^: and boxes
Maybe you'll like this.
f=: 13 :'y >.(1 |. 2 = y)*+:y'
f 1 2 3 2 2 4 2
2 2 6 4 2 8 2
f
] >. +: * 1 |. 2 = ]
Linda
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