Did you try
33 b.~ _1
?
Henry Rich
On 5/26/2014 3:07 PM, 'Pascal Jasmin' via Programming wrote:
The 2 fastest versions I've found on my computer:
100 timespacex '( + <: ) */ +:@:*:^:2 ] 1024 16'
3.4112e_6 4352
100 timespacex '(+ <:) +:^:14 *:^:4 ] 8 '
5.5744e_6 3072
The &. x: is obviously much more generic and practical for generating "medium"
sized numbers.
100 timespacex ' 2 <: &. x:@^ 63 '
8.064e_6 5632
The importance of all this, btw, is that there is a significant size penalty to
storing extended integers, as well as a time/space compromise in working with
them.
----- Original Message -----
From: 'Pascal Jasmin' via Programming <[email protected]>
To: "[email protected]" <[email protected]>
Cc:
Sent: Monday, May 26, 2014 2:35:14 PM
Subject: Re: [Jprogramming] 2^63
Might this be the fastest way of getting 2^63-1, without x: ?
(<: + ] ) +:^:14 *:^:4 ] 8
9223372036854775807
worth noting:
+:^:62 ] 2
9.22337e18
+:^:61 ] 2
4611686018427387904
2 <: &. x:@^ 63
9223372036854775807
---
actually this is probably best:
2 <: &. x:@^ 63
9223372036854775807
3!:0 ] 2 <: &. x:@^ 63
4
----- Original Message -----
From: Raul Miller <[email protected]>
To: Programming forum <[email protected]>
Cc:
Sent: Monday, May 26, 2014 2:02:01 PM
Subject: Re: [Jprogramming] 2^63
Here's an interesting bug (I can't call this kind of issue a feature if
it's not documented in the dictionary, can I?):
9223372036854775809
9223372036854775807
(And that's probably more important than the "using ^" issue.)
Thanks,
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