Function accurate::util::round3

pub fn round3<F>(s0: F, s1: F, s2: F) -> F where
    F: Round3, 

Correctly rounded sum of three non-overlapping numbers

Calculates the correctly rounded sum of three numbers s0, s1 and s2 which are non-overlapping, i.e.:

s0.abs() > s1.abs() > s2.abs()
fl(s0 + s1) = s0
fl(s1 + s2) = s1

References

Based on Zhu and Hayes 09