[Jprogramming] Operations on boolean lists

[Thomas Costigliola]

Thanks for the heads up. Now I have to check all the 1&e. in my code.

At least for rank 1 Boolean arguments it seems like +./ and 1&e.
should execute the same code so as not to tax the un-enlightened.

On Thu, Oct 13, 2011 at 6:40 PM, Roger Hui <rhui000 at shaw.ca> wrote:
> +./@E. is backed by special code.  Thus:
>
>   ts=: 6!:2 , 7!:2@]
>
>   b=: 0<1e6 ?@$ 4
>   ts '(42$1) +./@E. b'
> 0.000961575 1600
>   ts '42 (1 e. ([#1:) E. ]) b'
> 0.00308224 1.05018e6
>
> Another phrase finds the maximum number of
> consecutive 1s: cut where b has a 1 preceded
> by a 0, and sum the cut.
>
>   >./ (b>}:0,b) +/;.1 b
> 42
>   ts '>./ (b>}:0,b) +/;.1 b'
> 0.0198919 4.19635e6
>
>
>
> ----- Original Message -----
> From: Thomas Costigliola <tcostigl at gmail.com>
> Date: Thursday, October 13, 2011 15:18
> Subject: Re: [Jprogramming] Operations on boolean lists
> To: Programming forum <programming at jsoftware.com>
>
>> N (1 e.([#1:)E.]) 1 0 ...
>>
>> On Oct 13, 2011 5:58 PM, "David Vaughan"
>> <purpleblues13 at googlemail.com>wrote:
>> >
>> > How could I test if a boolean list contains at least n
>> consecutive 1's?
>> >
>> > e.g. for 3 consecutive 1's:
>> >
>> >   desiredverb 0 1 1 1 0 0
>> > 1
>> >   desiredverb 0 1 1 0 1 1
>> > 0
>> >   desiredverb 1 1 1 1 1 0
>> > 1
>
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