function max(x) {
    if (x.length === 0) {
        throw new Error("max requires at least one data point");
    }

    let value = x[0];
    for (let i = 1; i < x.length; i++) {
        if (x[i] > value) {
            value = x[i];
        }
    }
    return value;
}
This computes the maximum number in an array.

This runs in `O(n)`, linear time, with respect to the length of the array.

@param {Array<number>} x sample of one or more data points
@returns {number} maximum value
@throws {Error} if the length of x is less than one
@example
max([1, 2, 3, 4]);
// => 4