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Re: (long) sNaNs not what they could be...

> Date: Fri, 15 Oct 2010 18:54:44 -0400
> To: stds-1788                    <stds-1788@xxxxxxxxxxxxxxxxx>
> From: Michel Hack                          <hack@xxxxxxxxxxxxxx>
> Subject: (long) sNaNs not what they could be...
> . . .
> Btw, some machines (HP's PA-RISC if I remember correctly)
> do use a 1-bit to denote SNaN, and all-ones is an SNaN, but
> this complicates the Quieting operation, which may have to
> insert another 1-bit to prevent decaying to Infinity.
> Michel.

	Oh, Michel, I know this all too well.

	I was HP's "man on the 754 committee"
	in 1980.

	I was on the team that designed that
	first generation of floating-point
	chips at HP in 1981.

	I made that choice.

	The wrong one as it happens.