/**
 * Returns the product of a double-double-precision floating point number and a
 * double.
 *
 * * slower than ALGORITHM 8 (one call to fastTwoSum more) but about 2x more
 * accurate
 * * relative error bound: 1.5u^2 + 4u^3, i.e. fl(a+b) = (a+b)(1+ϵ),
 * where ϵ <= 1.5u^2 + 4u^3, u = 0.5 * Number.EPSILON
 * * the bound is very sharp
 * * probably prefer `ddMultDouble2` due to extra speed
 *
 * * ALGORITHM 7 of https://hal.archives-ouvertes.fr/hal-01351529v3/document
 * @param y a double
 * @param x a double-double precision floating point number
 */
declare function ddMultDouble1(y: number, x: number[]): number[];
/**
 * Returns the product of a double-double-precision floating point number and a double.
 *
 * * faster than ALGORITHM 7 (one call to fastTwoSum less) but about 2x less
 * accurate
 * * relative error bound: 3u^2, i.e. fl(a*b) = (a*b)(1+ϵ),
 * where ϵ <= 3u^2, u = 0.5 * Number.EPSILON
 * * the bound is sharp
 * * probably prefer this algorithm due to extra speed
 *
 * * ALGORITHM 8 of https://hal.archives-ouvertes.fr/hal-01351529v3/document
 * @param y a double
 * @param x a double-double precision floating point number
 */
declare function ddMultDouble2(y: number, x: number[]): number[];
export { ddMultDouble1, ddMultDouble2 };