Linda, you may want to look up two's-compliment arithmetic, see
http://en.wikipedia.org/wiki/Two's_complement
Your idea in hcla is nice. Can you figure out a way to calculate the
number of 2's required for the left argument? For example you would
need four 2's for
(2 2 2 2 hcla i: 5) -: hc i: 5
1
On 12/10/2011 3:56 AM, Linda Alvord wrote:
> Kip, Is this what you are looking for:
>
>
> hcla=: 13 :'x#:y'
> ]d=:2 2 2 hcla i:2
> 1 1 0
> 1 1 1
> 0 0 0
> 0 0 1
> 0 1 0
>
> hcinvla=:hcla^:_1 hcla
> hcinvla d
> |length error: hcinvla
> | hcinvla d
>
> hcla
> #:
> hcinvJ=:#:^:_1
> hcinvJ
> #:^:_1
>
> hcinvJ d
> 6 7 0 1 2
>
> hcinvla
> #.
> hcinvla=: 13 :'#.y'
> hcinvla d
> 6 7 0 1 2
>
> Raul's new improved answer hc doesn't appear to deal with the negative
> values. My inverse does the best it can with the data it gets.
>
> My code is mostly from the dictionary. I'm not sure what would be the best
> way to deal with negative binary numbers. Maybe I'll remember something
> about that a little later.
>
> Linda
>
>
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]] On Behalf Of Kip Murray
> Sent: Saturday, December 10, 2011 1:02 AM
> To: Programming forum
> Subject: Re: [Jprogramming] How #: should have been designed
>
> Now we need an inverse for Raul's improved #: ("hash colon")
>
> hc NB. Raul's improved #:
> {.@#:@(,: (2 * |))
>
> hc i: 2
> 1 1 0
> 1 1 1
> 0 0 0
> 0 0 1
> 0 1 0
>
> hcinv NB. improvement sought
> 2&#.`(2&#.@}. - 2 ^<:@#)@.{."1
>
> hcinv hc i: 2
> _2 _1 0 1 2
>
> On 12/8/2011 2:41 PM, Raul Miller wrote:
> ...
> But this would work just as well, as a model:
>
> {.@#:@(,: 2 * |)i:2
> 1 1 0
> 1 1 1
> 0 0 0
> 0 0 1
> 0 1 0
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