Re: [LinuxBIOS] Another dumb C question

[Joseph Smith]

Quoting Joseph Smith <[e-mail]>:
> Quoting Corey Osgood <[e-mail]>:
> > Joseph Smith wrote:
> > > Quoting Peter Stuge <[e-mail]>:
> > > > > value = 9
> > > > >
> > > > > (2 << (value - 1))
> > > > Bit shift is fine methinks but I would suggest:
> > > >
> > > > (1 << value)
> > > >
> > > > instead of
> > > >
> > > > (2 << (value - 1))
> > > >
> > > > //Peter
> > >
> > > Not sure I understand. I am trying to get 2 "to the power of" value.
> > >
> > > if value = 9
> > > (1 << value)
> > > This equals 18???? Not 2^9 = 512
> > > where
> > > (2 << (value - 1))
> > > (2 << (9 - 1))
> > > 2 << 8 = 512
> > >
> > > Thanks - Joe
> >
> > remember that 2 = (1 << 1). so 2 << (value - 1) = 1 << value. I'm not
> > sure where you're getting an 18 from, that makes no sense at all (since
> > 18 in either hex or dec has two non-zero bits, so it's impossible to get
> > that result with just that binary shift).
> >
> > -Corey
>
> Well lets see if value = 9, which is 1001 in binary.
> If you bitshift 1001 one position to the left it becomes 10010, correct?
> Which is 18 in decimal.
>
> Thanks - Joe

Nevermind I get it. I was looking at it bass ackwards :-)
Sorry, I'm a little tired.


Thanks - Joe