Decimals and other numbers
Marko Rauhamaa
marko at pacujo.net
Fri Jan 9 07:45:04 CET 2015
Dave Angel <davea at davea.name>:
> What you don't say is which behavior you actually expected. Since 0**0
> is undefined mathematically, I'd expect either an exception or a NAN
> result.
IEEE 754 mandates that 0**0 should evaluate to 1:
<URL: http://en.wikipedia.org/wiki/NaN#Operations_generating_NaN>
The standard pow function and the integer exponent pown function
define 0**0, 1**∞, and ∞**0 as 1.
The powr function defines all three indeterminate forms as invalid
operations and so returns NaN.
Should IEEE 754's anomalies spill over to decimal, is a different
question.
Marko
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