import type { NutrientResult, nutrientColHeaders, Units } from './csv.js';
export { Units };
export declare function convertUnits(from: NutrientResult | NutrientResult[], to?: Units): NutrientResult[];
declare type UnitSpec = {
    Element: string;
    ValueUnit: string;
};
export declare type UnitsSpec = {
    [element: keyof typeof nutrientColHeaders]: UnitSpec;
};
export declare const standardUnits: Units;
export declare function validateUnits(nrs: NutrientResult[]): NutrientResult[];