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Gradual-Underflow Wars

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Nowadays we take IEEE-754 arithmetic for granted (at least in the hardware; 
language support is another matter, unless you’re using an enlightened 
language like GCC or Python). It was a different matter in the late 1970s, 
when the idea for a standard floating-point architecture first came 
together, spurred by Intel’s development of its 8087 chip.

Hard to believe it now, but the most controversial aspect of the proposal 
was its support for denormalized numbers, to fill in the underflow gap 
between the closest normalized number to zero, and zero itself. In theory 
you could write code that would work correctly without such help, but most 
people didn’t have that kind of skill in numerics. And still don’t.

<http://www.eecs.berkeley.edu/~wkahan/ieee754status/754story.html>

Kahan also has a paper elsewhere deriding the floating-point limitations of 
Java. Java does not distinguish between NaN and infinity, and provides no 
way of querying and controlling floating-point exceptions (in the IEEE-754 
sense of “exception”).

His paper was published in 1998, and is still a valid criticism today.

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Gradual-Underflow Wars Lawrence D'Oliveiro <ldo@geek-central.gen.new_zealand> - 2011-05-07 20:50 +1200
  Re: Gradual-Underflow Wars Lew <noone@lewscanon.com> - 2011-05-07 08:06 -0400

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