DoubleSummaryStatistics

open class DoubleSummaryStatistics : DoubleConsumer

<code>DoubleSummaryStatistics stats = doubleStream.collect(DoubleSummaryStatistics::new,
                                                       DoubleSummaryStatistics::accept,
                                                       DoubleSummaryStatistics::combine);
  </code>

<code>DoubleSummaryStatistics stats = people.stream()
      .collect(Collectors.summarizingDouble(Person::getWeight));
 </code>

DoubleSummaryStatistics

DoubleSummaryStatistics()

Constructs an empty instance with zero count, zero sum, Double.POSITIVE_INFINITY min, Double.NEGATIVE_INFINITY max and zero average.

DoubleSummaryStatistics

DoubleSummaryStatistics(
    count: Long, 
    min: Double, 
    max: Double, 
    sum: Double)

Constructs a non-empty instance with the specified count, min, max, and sum.

If count is zero then the remaining arguments are ignored and an empty instance is constructed.

If the arguments are inconsistent then an IllegalArgumentException is thrown. The necessary consistent argument conditions are:

• count >= 0
• (min <= max && !isNaN(sum)) || (isNaN(min) && isNaN(max) && isNaN(sum))

Parameters
count	Long: the count of values
min	Double: the minimum value
max	Double: the maximum value
sum	Double: the sum of all values

Exceptions
java.lang.IllegalArgumentException	if the arguments are inconsistent

accept

open fun accept(value: Double): Unit

Records another value into the summary information.

Parameters
value	Double: the input value

combine

open fun combine(other: DoubleSummaryStatistics!): Unit

Combines the state of another DoubleSummaryStatistics into this one.

Parameters
other	DoubleSummaryStatistics!: another DoubleSummaryStatistics

Exceptions
java.lang.NullPointerException	if other is null

getAverage

fun getAverage(): Double

Returns the arithmetic mean of values recorded, or zero if no values have been recorded.

The computed average can vary numerically and have the special case behavior as computing the sum; see getSum for details.

Return
Double	the arithmetic mean of values, or zero if none

getCount

fun getCount(): Long

Return the count of values recorded.

Return
Long	the count of values

getMax

fun getMax(): Double

Returns the maximum recorded value, Double.NaN if any recorded value was NaN or Double.NEGATIVE_INFINITY if no values were recorded. Unlike the numerical comparison operators, this method considers negative zero to be strictly smaller than positive zero.

Return
Double	the maximum recorded value, Double.NaN if any recorded value was NaN or Double.NEGATIVE_INFINITY if no values were recorded

getMin

fun getMin(): Double

Returns the minimum recorded value, Double.NaN if any recorded value was NaN or Double.POSITIVE_INFINITY if no values were recorded. Unlike the numerical comparison operators, this method considers negative zero to be strictly smaller than positive zero.

Return
Double	the minimum recorded value, Double.NaN if any recorded value was NaN or Double.POSITIVE_INFINITY if no values were recorded

getSum

fun getSum(): Double

Returns the sum of values recorded, or zero if no values have been recorded.

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 double values. Because of the unspecified order of operations and the possibility of using differing summation schemes, the output of this method may vary on the same input values.

Various conditions can result in a non-finite sum being computed. This can occur even if the all the recorded values being summed are finite. If any recorded value is non-finite, the sum will be non-finite:

• If any recorded value is a NaN, then the final sum will be NaN.
• If the recorded values contain one or more infinities, the sum will be infinite or NaN.
  • If the recorded values contain infinities of opposite sign, the sum will be NaN.
  • If the recorded values contain infinities of one sign and an intermediate sum overflows to an infinity of the opposite sign, the sum may be NaN.

It is possible for intermediate sums of finite values to overflow into opposite-signed infinities; if that occurs, the final sum will be NaN even if the recorded values are all finite. If all the recorded values are zero, the sign of zero is not guaranteed to be preserved in the final sum.

Return
Double	the sum of values, or zero if none

toString

open fun toString(): String

Returns a non-empty string representation of this object suitable for debugging. The exact presentation format is unspecified and may vary between implementations and versions.

Return
String	a string representation of the object.