Exact integer-valued floats

[Tim Roberts]

Dennis Lee Bieber <wlfraed at ix.netcom.com> wrote:
>
>On 22 Sep 2012 01:36:59 GMT, Steven D'Aprano wrote:
>> 
>> For non IEEE 754 floating point systems, there is no telling how bad the 
>> implementation could be :(
>
>	Let's see what can be found...
>
>	IBM 360: Same as Sigma-6 (no surprise; hearsay is the Sigma was
>designed by renegade IBM folk; even down to using EBCDIC internally --
>but with a much different interrupt system [224 individual interrupt
>vectors as I recall, vs the IBM's 7 vectors and polling to find what
>device]).

The Control Data 6000/Cyber series had sign bit and 11-bit exponent, with
either a 48-bit mantissa or a 96-bit mantissa, packed into one or two
60-bit words.  Values were not automatically normalized, so there was no
assumed 1 bit, as in IEEE-754.
-- 
Tim Roberts, timr at probo.com
Providenza & Boekelheide, Inc.