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,

-- 
Raul






On Mon, May 26, 2014 at 1:55 PM, 'Pascal Jasmin' via Programming <
[email protected]> wrote:

> is there a way to get ^ to make a 64bit number without it being extended
> precision?  I guess an efficient alternative to ^ if that is not possible:
>
>    2^63
> 9.22337e18
>    2^63x
> 9223372036854775808
>    9223372036854775808
> 9223372036854775807
>
> Note that the last line is probably a problem. The answer is the largest
> non extended integer, but still unwelcome change from the input.
>
>    9223372036854775808-1
> 9223372036854775806
>    9223372036854775809-1
> 9223372036854775806
>
> I guess this works
>
>    (<: + ] ) 4611686018427387904
>  NB. 2^62x
> 9223372036854775807
>
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