On 2/28/07, Ralph G Selfridge <[EMAIL PROTECTED]> wrote:
In the argument about tacit or explicit I offer the following verb, comes
from a Black-Scholes algorithm. Lets assume we have the verb cndn. I won't
claim I can't make this tacit, I will claim it won't be easy and or
readable and far more work than I think its worth. And I doubt it will run
any faster.
bsn=: 3 : 0
's x t r v'=.y
|(s,x*^-r*t)-/ .*cndn 1 _1*/~((^.s%x)+t*r(+,-)-:*:v)%v*%:t
)
That's not very fun without the surrounding context (definition of
cndn and sample arguments).
That said, a literal translation seems completely straightforward
(but not as concise):
'`s x t r v'=: (0{::])`(1{::])`(2{::])`(3{::])`(4{::])
bsn=: [:|(s,x*[:^[:-r*t)-/.*[:cndn 1 _1*/~(([:^.s%x)+t*r(+,-)[:-:[:*:v)%v*[:%:t
That said, both versions of bsn use 'x' in a fashion that's likely to
confuse someone. But, at least with the tacit form it's trivial to
eliminate from the definition:
bsn=: bsn f.
--
Raul
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