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[John G Dobnick]

[Just who was that masked line eater, anyway?]

> 
> BTW, I believe the machine with the unusual floating point might have been a
> univac 1100, but I could be mistaken.
> 
> 	Michael Meissner
> 	Data General

Speaking of the Sperry 1100 (Univac ceased to exist when Sperry Corp., in their
infinite wisdom, decided to make a name change at the start of their fiscal
year (April 1 -- yup! You heard me right!)) floating point formats...

It *is* possible to have a floating point zero on the Sperry 1100 that is
*not* all zero bits (or all *one* bits -- this is a one's-complement machine
and thus has *two* zeros).  However, such a F.P. zero is *un*-normalized,
and is likely to cause undefined results when used in computations.  A
*normalized* F.P. zero is defined as a floating point number with *all*
bits the same as the sign bit; this is what one normally sees and uses.

Aside:  Un-normalized F.P. operands *do* produce defined results when used
	with the ADD and ADD-NEGATIVE (also known as SUBTRACT in certain
	circles) operations.  You may get less precision in the results
	if you do this.  I have seen one case where this was, in fact,
	done deliberately to produce a *scaled* result.  Needless to say,
	such *trickery* is highly machine dependent.
-- 

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John G Dobnick
Computing Services Division @ University of Wisconsin - Milwaukee
(...ihnp4!uwmcsd1!jgd)