Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site kobold.UUCP Path: utzoo!linus!decvax!genrad!grkermit!masscomp!kobold!tjt From: tjt@kobold.UUCP Newsgroups: net.arch Subject: Re: Re: Complement Arithmetic - (nf) Message-ID: <271@kobold.UUCP> Date: Mon, 6-Feb-84 11:19:10 EST Article-I.D.: kobold.271 Posted: Mon Feb 6 11:19:10 1984 Date-Received: Thu, 9-Feb-84 07:46:31 EST References: <5354@uiucdcs.UUCP> Organization: Masscomp, Westford, MA Lines: 25 parsec!wallach wants to why the IEEE floating point standard uses a sign-magnitude representation while representing integers in 2's-complement notation. I can't speak for the IEEE specifiers, but I always thought the basic floating point representation of: ---------------------- | S | EXP | Mantissa | ---------------------- EXP-offset where S is a sign bit and the mantissa gets multiplied by B used the offset notation of the exponent so that the machine integer comparison instructions would also work for floating point. I didn't study the IEEE specification closely enough to know if this still works, especially with unnormalized numbers. It is also true that using integer comparison instructions would not trap "illegal" values (e.g. -0). -- Tom Teixeira, Massachusetts Computer Corporation. Westford MA ...!{ihnp4,harpo,decvax}!masscomp!tjt (617) 692-6200 x275