Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

Re: As simple as it is now, I am still against motion 24.03...

Dan Zuras Intervals wrote:

	Folks,

	The motion is now, & I quote:

	The Motion: Every IEEE 1788 compliant system SHALL provide
	the four basic arithmetic operations addition, subtraction,
	multiplication, and division with rounding downwards and
	upwards. Type conversions with directed roundings SHALL
	also be provided.
From our point of view (constraint programming and use in global optimization), we often need both rounding directions for the same operations. 

Thus it would be more useful to have operations that take a list of
reals and return a (preferably the tightest) representable interval
enclosing the result of an operation with them. Addition and inner
product of arbitrarily many inputs, subtraction, division with two
arguments, and sqrt with one argument.

This fully substitutes for directed rounding (probably at virtually
no extra cost if done in hardware).


Arnold Neumaier