org.jfree.data.statistics

Class BoxAndWhiskerCalculator


public abstract class BoxAndWhiskerCalculator
extends java.lang.Object

A utility class that calculates the mean, median, quartiles Q1 and Q3, plus a list of outlier values...all from an arbitrary list of Number objects.

Method Summary

static BoxAndWhiskerItem
calculateBoxAndWhiskerStatistics(List values)
Calculates the statistics required for a BoxAndWhiskerItem from a list of Number objects.
static BoxAndWhiskerItem
calculateBoxAndWhiskerStatistics(List values, boolean stripNullAndNaNItems)
Calculates the statistics required for a BoxAndWhiskerItem from a list of Number objects.
static double
calculateQ1(List values)
Calculates the first quartile for a list of numbers in ascending order.
static double
calculateQ3(List values)
Calculates the third quartile for a list of numbers in ascending order.

Method Details

calculateBoxAndWhiskerStatistics

public static BoxAndWhiskerItem calculateBoxAndWhiskerStatistics(List values)
Calculates the statistics required for a BoxAndWhiskerItem from a list of Number objects. Any items in the list that are null, not an instance of Number, or equivalent to Double.NaN, will be ignored.
Parameters:
values - a list of numbers (a null list is not permitted).
Returns:
A box-and-whisker item.

calculateBoxAndWhiskerStatistics

public static BoxAndWhiskerItem calculateBoxAndWhiskerStatistics(List values,
                                                                 boolean stripNullAndNaNItems)
Calculates the statistics required for a BoxAndWhiskerItem from a list of Number objects. Any items in the list that are null, not an instance of Number, or equivalent to Double.NaN, will be ignored.
Parameters:
values - a list of numbers (a null list is not permitted).
stripNullAndNaNItems - a flag that controls the handling of null and NaN items.
Returns:
A box-and-whisker item.
Since:
1.0.3

calculateQ1

public static double calculateQ1(List values)
Calculates the first quartile for a list of numbers in ascending order. If the items in the list are not in ascending order, the result is unspecified. If the list contains items that are null, not an instance of Number, or equivalent to Double.NaN, the result is unspecified.
Parameters:
values - the numbers in ascending order (null not permitted).
Returns:
The first quartile.

calculateQ3

public static double calculateQ3(List values)
Calculates the third quartile for a list of numbers in ascending order. If the items in the list are not in ascending order, the result is unspecified. If the list contains items that are null, not an instance of Number, or equivalent to Double.NaN, the result is unspecified.
Parameters:
values - the list of values (null not permitted).
Returns:
The third quartile.