[Cfp-interest 1222] rootn

[Fred J. Tydeman]

IEEE-754 (2019)

rootn (+INF, n) is +INF for n > 0
rootn (-INF, n) is -INF for odd n > 0
rootn (-INF, n) is qNaN and signals the invalid operation exception for even n > 0
rootn (+INF, n) is +0 for n < 0
rootn (-INF, n) is -0 for odd n < 0
rootn (-INF, n) is qNaN and signals the invalid operation exception for even n < 0.


CFP TS 18661-4 (after N2309)

-- rootn(+INF, n) is +INF for n > 0.
-- rootn(-INF, n) is -INF for odd n > 0.
-- rootn(-INF, n) is qNaN and raises the "invalid" floating-point exception for even n > 0.
-- rootn(+INF, n) is +0 for n < 0.
-- rootn(-INF, n) is -0 for odd n < 0.
-- rootn(-INF, n) is qNaN and raises the "invalid" floating-point exception for even n < 0.

They match.


---
Fred J. Tydeman        Tydeman Consulting
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