# [LAU] logical AND in Faust

Mon Nov 30 16:21:13 EST 2009

```Ok, I was thinking about that, too. But I cannot figure out how it works.

Ok, I got it: for n = 3 and x = 4 (fourth round): 100 & 011 = 000. I must have
had a brain stoppage, when I tried this last time ...

Thank you very much. Now I feel ashamed that I try to work with faust, but
don't even know how bitwise operation is done. Anyway, you should check out
faust. It's realy awesome.

Sincerely, Bjoern

On Monday 30 November 2009 21:20:33 Arnold Krille wrote:
> Disclaimer: I don't (yet) know faust
>
> On Monday 30 November 2009 20:38:12 Bjoern Lindig wrote:
> > I have a problem understanding this piece of faust-code:
> > index( n ) = &( n - 1 ) ~ + ( 1 );
> > It is from the faust-soft-computing.pdf. I do understand that it works
> > like a counter and I think it should jump back to 0 when it reaches n -
> > 1. But what exactly is the logical AND operator doing?
>
> I think its not a logical AND for expressions but a bitwise AND. Which
>  means that only the bits that are set in both arguments pass. Which would
>  make sense to have the counter wrap...
>
> Maybe that helps,
>
> Arnold
>

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