Re: float with 24-bit resolution

[Simon Wright <simon@pushface.org>]

"Matthew Heaney" <matthewjheaney@earthlink.net> writes:

> <mailbox@adrianhoe.nospam.com.my> wrote in message
> news:3F3CCB0F.543478AF@adrianhoe.nospam.com.my...
> > Hi,
> >
> > I looked through the LRM and searched CLA but I could not find any
> > solution. Perhaps I've overlook somewhere.
> >
> > I need a float with 24-bit resolution. My data needs to be encoded into
> > 24 bits at a scaling of 720 degrees / 2^24 bits with the most
> > significant bit being the sign bit. This results in a value that ranges
> > from +359.9999571 degrees (0x7FFFFF) to -360.0000000 degrees (0x800000)
> > at increments of approximately 4.291534424e-5 degrees per bit.
> 
> You're not asking for a floating point type at all -- you're asking for a
> fixed point type.

to OP: in Ada, there are *real* numbers (which can have non-integer
values): the way in which real numbers can be represented is either in
floating-point or fixed-point. floating-point format has a mantissa
and an exponent, and corresponds to C float or double; fixed-point has
no exponent, and no C analog either, it's just 'int where the least
significant bit represents (in your case) 2**-24'.