[Stds-754] nomenclature for representable entities

[Michel Hack (1-914-784-7648) <hack@xxxxxxxxxxxxxx>]

Ivan Godard wrote:
> How about the 24 redundant decimals?

Those are a matter of encoding, not representation, and so are not
affected by this discussion.  Among the redundant encodings are also
the BID zeros that have a binary significand that is out-of-range.

BFP is easy:  except for infinity, there is a one-to-one map between
representations and encodings, and there is also a one-to-one map
between values and representations (if one accepts +0 and -0 as
separate "values"; if not, zero is an exception).

DFP introduces many representations for each value, as well as many
encodings for each representation -- never mind two encoding styles.

Michel.
Sent: 2006-08-28 21:14:42 UTC