Yes.  And  x |~ d  too.


----- Original Message -----
From: Brian Schott <[EMAIL PROTECTED]>
Date: Thursday, October 26, 2006 5:43 am
Subject: Re: [Jprogramming] Integer division and remainder

> Roger,
> 
>       How about x #:~0,d ; has it been improved
> automatically?  This family member was a complete surprise
> to me -- neat.
> 
> On Wed, 25 Oct 2006, Roger Hui wrote:
> 
> + There are 3 verbs in the family:
> +
> + x <[EMAIL PROTECTED] d   integer quotient
> + d|x        integer remainder
> + (0,d)#:x   integer quotient and remainder
> +
> + All three members of the family have been improved,
> + with the largest improvement occurring when d is
> + a positive power of 2.
> +
> + Preliminary benchmarks:
> +
> + x=: _2e5 + 1e6 [EMAIL PROTECTED] 4e5
> +
> + ts=: 6!:2 , 7!:[EMAIL PROTECTED]
> + ts 'Expression'
> +
> + Expression          J6.02x                J6.01            Ratio
> + x <[EMAIL PROTECTED] 256   0.0055291 4.19507e6   0.1623434 2.09723e7   
> 29.36 5.00
> + 256 | x      0.0056425 4.19494e6   0.0257975 4.19494e6    4.57 1.00
> + 0 256 #: x   0.0092815 8.38925e6   0.0600597 8.38925e6    6.47 1.00


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