/**
 * Apply a join operation to a list of values
 * @param joinOperator - The join operation to apply, the following are supported:
 * - 'sum' - Sum the values
 * - 'mean' - Mean the values
 * - 'min' - Min the values
 * - 'max' - Max the values
 * @param values - The list of values to apply the join operation to
 * @returns The result of the join operation
 */
export declare function applyJoin(joinOperator: string, values: number[]): string | number;