I toyed a bit with John Randall's 'run' verb (
http://www.jsoftware.com/jwiki/NYCJUG/2012-10-10 ) and got some speedup
by starting with an rotated (3 places to the right) index vector:
ts 'P=.{. display 1 run ~ i.9'
19.1419 3.4871e7
ts 'Q=.{. display 1 run ~_3|. i.9'
2.83672 3.48714e7
note: reorder the first three rows of Q
P-: (0 1 2) {`(_1&|.@[)`]} Q
1
run=: 3 : 0
y run ~i.9
:
n=. 0
r=. 0 9 $ 0
stack=. ,<,: x
while. (#stack) *. n<y do.
top=. >{: stack
stack=. }: stack
if. 9=# top do.
r=. r,A. top
n=. >:n
else.
stack=. stack,|. <"_1 trim xtend top
end.
end.
r
)
--
Met vriendelijke groet,
@@i = Arie Groeneveld
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