Function expansion_sum_zeroelim2

pub fn expansion_sum_zeroelim2(e: &[f64], f: &[f64], h: &mut [f64]) -> usize

Sums two expansions, eliminating zero components from the output expansion.

Sets h = e + f. See the paper for details.

Maintains the nonoverlapping property. If round-to-even is used (as
with IEEE 754), maintains the nonadjacent property as well. (That is, if e has one of these properties, so will h.) Does NOT maintain the
strongly nonoverlapping property.