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more about binary floating-point arithmetic



Another property of the binary floating-point arithmetic used by computers
is that the associative law doesn't hold for addition.
Evaluate these two Emacs Lisp forms:
(+ (+ (expt 10 16.2) 0.7) 0.4)
(+ (expt 10 16.2) (+ 0.7 0.4))
By the associative law, both calculations should yield the same answer.
They don't!

-- Chris

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