/**
 * Returns the result of adding two double-double-precision floating point
 * numbers.
 *
 * * relative error bound: 3u^2 + 13u^3, i.e. fl(a+b) = (a+b)(1+ϵ),
 * where ϵ <= 3u^2 + 13u^3, u = 0.5 * Number.EPSILON
 * * the error bound is not sharp - the worst case that could be found by the
 * authors were 2.25u^2
 *
 * ALGORITHM 6 of https://hal.archives-ouvertes.fr/hal-01351529v3/document
 * @param x a double-double precision floating point number
 * @param y another double-double precision floating point number
 */
declare function ddAddDd(x: number[], y: number[]): number[];
export { ddAddDd };