Function quantityExponent

src/util/number.ts:581–598

(val: number)

 * @return
 */
export function quantityExponent(val: number): number {
    if (val === 0) {
        // PENDING: like IEEE754 use exponent `0` in this case.
        // but methematically, exponent of zero is `-Infinity`.
        return 0;
    }

    let exp = mathFloor(mathLog(val) / mathLN10);
    /**
     * exp is expected to be the rounded-down result of the base-10 log of val.
     * But due to the precision loss with Math.log(val), we need to restore it
     * using 10^exp to make sure we can get val back from exp. #11249
     */
    if (val / mathPow(10, exp) >= 10) {
        exp++;
    }
    return exp;
}

export const NICE_MODE_ROUND = 1 as const;
export const NICE_MODE_MIN = 2 as const;