OK Roger - trapped by type the second time this week!
NB. as you say:
(datatype@".;ts)'(**<.@:**)(100000$i:5)--:ct'
+--------+-------------------+
|floating|0.0105938 3.67232e6|
+--------+-------------------+
NB. the following forced integer is still quite nifty
(datatype@".;ts)'(<[EMAIL PROTECTED]<.@:**)(100000$i:5)--:ct'
+-------+-------------------+
|integer|0.0309942 4.72128e6|
+-------+-------------------+
NB. but
(datatype@".;ts)'(**<.@:|)(100000$i:5)--:ct'
+-------+-------------------+
|integer|0.0255591 4.19622e6|
+-------+-------------------+
... so the more natural way is preferable after all
if/when integer results are required.
Thanks
Mike
Roger Hui wrote:
NB. there must be some optimisation here?!
ts'(**<.@:**)(100000$i:5)--:ct'
0.0108771 3.67232e6
There are no optimizations. The expression is fast
because it avoids the most expensive operation
executed by the other expressions -- the monad <.
on floats.
BTW, the result of the expression is a float and
is not necessarily an exact integer:
] b=: (**<.@:**) 5+-:ct
5
b-5
2.84217e_14
----- Original Message -----
From: Mike Day <[EMAIL PROTECTED]>
Date: Monday, October 23, 2006 11:12 am
Subject: Re: [Jprogramming] fuzzy <.0
... but the timings aren't so good - perhaps that
doesn't matter.
ts'<.`0:@.(0=*)("0) (1000000$i:5)--:ct'
0.995482 5.82e7
NB. similar avoiding the "0 test:
ts'(<.*0:~:*) (1000000$i:5)--:ct'
0.279156 3.04111e7
NB. there must be some optimisation here?!
ts'(**<.@:**)(100000$i:5)--:ct'
0.0108771 3.67232e6
M
bill lam wrote:
bill lam wrote:
I also try <.`0:@.(1:=>:)("0)
another candidate may be <.`0:@.(0:=*)("0) as monad * is
tolerant when comparing
with 0.
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