/**
 * Wilder's Moving Average / RMA.
 * Implements the Wilder smoothing recurrence (rma = (rma*(period-1) + x)/period).
 * When `skipna` is true NaNs are ignored during seeding and updates; otherwise
 * a dense fast-path is used for NaN-free inputs.
 * @param source Input series
 * @param period Smoothing period (must be > 0)
 * @param skipna Whether to ignore NaNs during computation (default: true)
 * @returns Float64Array of RMA values (NaN before window fills)
 */
export declare function rma(source: ArrayLike<number>, period: number, skipna?: boolean): Float64Array;