The value of a floating-point sum is a function both of the + * input values as well as the order of addition operations. The + * order of addition operations of this method is intentionally + * not defined to allow for implementation flexibility to improve + * the speed and accuracy of the computed result. + * + * In particular, this method may be implemented using compensated + * summation or other technique to reduce the error bound in the + * numerical sum compared to a simple summation of {@code double} + * values. + * + * @apiNote Sorting values by increasing absolute magnitude tends to yield + * more accurate results. * * @return the sum of values, or zero if none */ @@ -153,13 +165,21 @@ } /** - * Returns the arithmetic mean of values recorded, or zero if no values have been - * recorded. The average returned can vary depending upon the order in - * which values are recorded. This is due to accumulated rounding error in - * addition of values of differing magnitudes. Values sorted by increasing - * absolute magnitude tend to yield more accurate results. If any recorded - * value is a {@code NaN} or the sum is at any point a {@code NaN} then the - * average will be {@code NaN}. + * Returns the arithmetic mean of values recorded, or zero if no + * values have been recorded. + * + * If any recorded value is a NaN or the sum is at any point a NaN + * then the average will be code NaN. + * + *
The average returned can vary depending upon the order in + * which values are recorded. + * + * This method may be implemented using compensated summation or + * other technique to reduce the error bound in the {@link #getSum + * numerical sum} used to compute the average. + * + * @apiNote Values sorted by increasing absolute magnitude tend to yield + * more accurate results. * * @return the arithmetic mean of values, or zero if none */