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Path: utzoo!watmath!watnot!watdcsu!herbie
From: herbie@watdcsu.UUCP (Herb Chong [DCS])
Newsgroups: net.arch
Subject: Re: IBM 360 float architecture problems
Message-ID: <1548@watdcsu.UUCP>
Date: Sat, 20-Jul-85 13:13:21 EDT
Article-I.D.: watdcsu.1548
Posted: Sat Jul 20 13:13:21 1985
Date-Received: Mon, 22-Jul-85 05:43:36 EDT
References: <36900010@ima.UUCP> <4006@alice.UUCP> <741@masscomp.UUCP>
Reply-To: herbie@watdcsu.UUCP (Herb Chong [DCS])
Organization: U of Waterloo
Lines: 24
Summary: 

In article <741@masscomp.UUCP> carter@masscomp.UUCP (Jeff Carter) writes:
>Its been a long time since I used 
>360/370 family machines, but I seem to remember that there 
>are indeed more exponent bits in double precision than single.
>( I could be wrong on the IBM details a lot of water's passed under
>  the bridge since I last used an IBM, I prefer computers that
>  accuarately reflect the calculations I intended to perform )
>This means that the IBM *will* overflow on conversions, totally
>unrelated to the rounding mode.

the first eight bits are sign, and 7 bit exponent in excess 64 notation
to the base 16 in all three floating point formats on 360/370
machines.  i have the principle of operations open right in front of me
as i write this.  you get maximum of 24, 56, and 112 bits of precision in
short, long, and extended floating point.

Herb Chong...

I'm user-friendly -- I don't byte, I nybble....

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