[Jprogramming] Two's-complement representation without #: or #.

[Raul Miller]

This is a variation on the ver binary defined a
http://jsoftware.com/pipermail/programming/2011-December/026213.html

effective_magnitude=: (2 * |)^:(-. at -: |)
bit_count=: 2 <.@^. 1>. >./@,@:effective_magnitude
extract_bit=: (%&2 at -&{. , ])  2&|
binary=: bit_count extract_bit@]^:["1 ,"0

tcr=: 2 | binary
or

tcr=: |@binary


-- 
Raul

On Wed, Dec 28, 2011 at 3:36 PM, Kip Murray <km at math.uh.edu> wrote:
> Now that we can do binary representation without #: or #. please write a
> two's-complement representation tcr without using #: or #. .
>
>    tcr _2
> 1 0
>    tcr i: 2
> 1 1 0
> 1 1 1
> 0 0 0
> 0 0 1
> 0 1 0
>
> A straightforward two's-complement value tcv explains the two's
> complement representation:
>
>    tcv =: ([: (2 p.~ |.) -@{. , }.)"1  NB. two's-complement value
>
>    tcv tcr _2
> _2
>    tcv tcr i: 2
> _2 _1 0 1 2
>
> Kip
>
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