Correct signum function according to the Haskell report.#60
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dmjio merged 1 commit intoarrayfire:masterfrom Mar 31, 2026
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In Haskell, `signum x` is defined to be -1 if x is negative, 1 if it is positive, and 0 if x is 0. This is different from ArrayFire's `sign` function, but it can be implemented in terms of this function.
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In Haskell,
signum xis defined to be -1 if x is negative, 1 if it is positive, and 0 if x is 0.(In particular,
signum x * abs x ≡ xshould hold.)This is different from ArrayFire's
signfunction (which yields 1 for a negative number and 0 else), but it can be implemented in terms of that function:x, we haveA.sign (-x) - A.sign x = 0 - 1 = -1x=0, we haveA.sign (-x) - A.sign x = 1 - 1 = 0x, we haveA.sign (-x) - A.sign x = 1 - 0 = 1