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/** * This is the internal implementation of quantiles: when you know * that the order is sorted, you don't need to re-sort it, and the computations * are faster. * * @param {Array<number>} x sample of one or more data points * @param {number} p desired quantile: a number between 0 to 1, inclusive * @returns {number} quantile value * @throws {Error} if p ix outside of the range from 0 to 1 * @throws {Error} if x is empty * @example * quantileSorted([3, 6, 7, 8, 8, 9, 10, 13, 15, 16, 20], 0.5); // => 9 */function quantileSorted(x, p) {    const idx = x.length * p;    if (x.length === 0) {        throw new Error("quantile requires at least one data point.");    } else if (p < 0 || p > 1) {        throw new Error("quantiles must be between 0 and 1");    } else if (p === 1) {        // If p is 1, directly return the last element        return x[x.length - 1];    } else if (p === 0) {        // If p is 0, directly return the first element        return x[0];    } else if (idx % 1 !== 0) {        // If p is not integer, return the next element in array        return x[Math.ceil(idx) - 1];    } else if (x.length % 2 === 0) {        // If the list has even-length, we'll take the average of this number        // and the next value, if there is one        return (x[idx - 1] + x[idx]) / 2;    } else {        // Finally, in the simple case of an integer value        // with an odd-length list, return the x value at the index.        return x[idx];    }}
export default quantileSorted;