Class SimulationStats

java.lang.Object
  |
  +--SimulationStats

public class SimulationStats

extends java.lang.Object

A class which hold all of the statistics for a Simulation or set of simulations. Provides ways to store the waiting time for all parties, as well as methods to display the results of the experiments

See Also:

Tester, Simulation

Field Summary

private int[]	counts How many of each party size has finished eating.
private static java.text.DecimalFormat	formatter Used for pretty printing.
private int	runCount The number of Simulations this SimulationStats is keeping track of
private double	runTime The total run time for all Simulations this SimulationStats is keeping track of
private double[][]	waitTimes The waiting times for the various parties.

Constructor Summary

SimulationStats(int[] partyCounts)
Initializes all stat keepers based upon expected party sizes

SimulationStats(SimulationStats set1, SimulationStats set2)
Creates a new set of SimulationStats by combining two sets of stats.

Method Summary

void	addRunTime(double time) Adds the total running time for a Simulation to this set of stats
void	addWaitTime(double time, int partySize) Adds a new waiting time for a specified party size to the statistics.
private double	average(double[] times, int count) Computes and returns the average of all values in an array
private int	countNonZero(double[] times) Counts and returns the number of non-zero elements in a specified array
private double[]	expand(double[] values, int multiplier) Converts an array of values into an expanded array of values by duplicating each value in the array multiplier number of times.
java.lang.String	getHeader() Returns a header which shows the meaning of all output values
double	getRunTime() Returns the run times for this set of statistics
private void	insert(double value, double[] values, int maxIndex) Inserts a value into an array of values, such that the array remains in sorted order.
private double	median(double[] values, int count) Computes and returns the median value in a sorted array of values
private double[]	merge(double[] vals1, int counts1, double[] vals2, int counts2) Merges two arrays, already assumed to be in sorted order, into a larger array in sorted order.
java.lang.String	toString() Returns a summary of all statistics in this set of stats

Methods inherited from class java.lang.Object

, clone, equals, finalize, getClass, hashCode, notify, notifyAll, registerNatives, wait, wait, wait

Field Detail

waitTimes

private double[][] waitTimes

The waiting times for the various parties. Each row number corresponds to the party size, and the column corresponds to the waiting time. Note that each row is stored in sorted order

counts

private int[] counts

How many of each party size has finished eating. The row number corresponds to the party size

runCount

private int runCount

The number of Simulations this SimulationStats is keeping track of

runTime

private double runTime

The total run time for all Simulations this SimulationStats is keeping track of

formatter

private static java.text.DecimalFormat formatter

Used for pretty printing. Shows up to two decimal places (initialized with "#.##")

Constructor Detail

SimulationStats

public SimulationStats(int[] partyCounts)

Initializes all stat keepers based upon expected party sizes

Parameters:

partyCounts - the number of parties of each size expected. The index number corresponds to the party size

SimulationStats

public SimulationStats(SimulationStats set1,
                       SimulationStats set2)

Creates a new set of SimulationStats by combining two sets of stats. It is assumed that both sets of stats contained the same range of party sizes.

Parameters:

set1 - the first set of stats

set2 - the second set of stats

Method Detail

merge

private double[] merge(double[] vals1,
                       int counts1,
                       double[] vals2,
                       int counts2)

Merges two arrays, already assumed to be in sorted order, into a larger array in sorted order.

Parameters:

vals1 - one set of values to merge

counts1 - the number of valid items in vals1. It is expected that 0 <= counts1 < vals1.length

vals2 - another set of values to merge

counts1 - the number of valid items in vals2. It is expected that 0 <= counts2 < vals2.length

Returns:

an array of size counts1 + counts 2 containing all of the values in vals1 and vals2

addWaitTime

public void addWaitTime(double time,
                        int partySize)

Adds a new waiting time for a specified party size to the statistics. It is assumed that the partySize is valid. It is important to note that if a party does not wait, you should still call this method; use a wait time of 0.

Parameters:

time - the amount of time the party waited

partySize - the size of the waiting party

addRunTime

public void addRunTime(double time)

Adds the total running time for a Simulation to this set of stats

Parameters:

time - the amount of time it took to run the simulation

getRunTime

public double getRunTime()

Returns the run times for this set of statistics

insert

private void insert(double value,
                    double[] values,
                    int maxIndex)

Inserts a value into an array of values, such that the array remains in sorted order.

Parameters:

value - the value to be inserted. the value will be inserted in the range [0, maxIndex]

values - an array of values in sorted order

maxIndex - the maximum possible index the value could be inserted

getHeader

public java.lang.String getHeader()

Returns a header which shows the meaning of all output values

toString

public java.lang.String toString()

Returns a summary of all statistics in this set of stats

Overrides:

toString in class java.lang.Object

expand

private double[] expand(double[] values,
                        int multiplier)

Converts an array of values into an expanded array of values by duplicating each value in the array multiplier number of times. That is, if the array initially contained:

[3, 2, 6, 7]

and multiplier were 3, the returned array would be

[3, 3, 3, 2, 2, 2, 6, 6, 6, 7, 7, 7]

Parameters:

values - an array of values to be expanded

multiplier - how many times to repeat each value in the array

countNonZero

private int countNonZero(double[] times)

Counts and returns the number of non-zero elements in a specified array

median

private double median(double[] values,
                      int count)

Computes and returns the median value in a sorted array of values

Parameters:

values - a sorted array of values

count - the number of valid entries in the array. It is expected that 0 < count < values.length

average

private double average(double[] times,
                       int count)

Computes and returns the average of all values in an array

Parameters:

values - the values in the array

count - the number of valid entries in the array. It is expected that 0 < count < values.length