R.E. Boss wrote:
tolower is not the fastest you can get. Hui gave in
http://www.jsoftware.com/pipermail/programming/2007-July/007302.html
rpl3a=: 4 : 0
'x0 x1'=. x
((x1,a.) {~ (x0,a.) i. ]) y
)
5 ts 'tolower y'[y=.a.{~1e6 [EMAIL PROTECTED] 256
0.024976126 8523008
5 ts ' (((65,.97)+"0 _ i.26){a.)rpl3a y'
0.0051314348 1054400
almost 40 times more efficiënt.
(tolower y) -:(((65,.97)+"0 _ i.26){a.)rpl3a y
1
The rpl3a method was essentially that used in J504, but replaced in J6
with a slower method that works with unicode, e.g.
[A =: 3 2$'aBc' , (u:39321 28207), 'E'
aB
c香
港E
toupper A
AB
C香
港E
(((65,.97)+"0 _ i.26){a.)rpl3a A
|index error: rpl3a
| ((x1,a.){~(x0,a.)i.])y
On the other hand, a 40x hit is quite a lot. It would be good to speed
up toupper and still work with unicode.
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