Re: Re:... replacement for 14.4 and C6.2 (interchange encodings)
On 2014-06-25 23:05:46 -0400, Michel Hack wrote:
> Interchange Level 4 encoding of an interval datum is a bit string
> that comprises, in the order defined above, the 754-2008 interchange
> encodings of the two floating-datums, and of the decoration represented
> as a small integer, as follows:
> ill 0
> trv 4
> def 8
> dac 12
> com 16
> This encoding permits future refinement without disturbing the natural
> propagation order of the decorations, and fits within the range of a C
> signed char, namely 0..127.
Here you could say "the range of a signed octet, namely 0..127", which
is a notion more general than C.
> Export and import of interchange formats normally occurs as a stream
> of octets (8-bit bytes), e.g. in a file or a network packet. There
> is therefore a need to define the mapping of the conceptual Level 4
> bit strings (as specified by 754-2008) and of the small integers used
> to encode decorations (out of scope for 754-2008) into a sequence of
> octets. There is also the fact that 754-2008 defines two distinct
> encodings of decimal formats, called BID and DPD.
I don't think that you want to do that (convert bit strings),
otherwise (inf,sup) could be reversed by the change of endianness
on the bit string. The endianness should apply on words (thus this
is a conversion from the Level 3 representation), not on the whole
bit string.
--
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <https://www.vinc17.net/>
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