io.praesid.livestats

Class LiveStats

java.lang.Object

io.praesid.livestats.LiveStats

All Implemented Interfaces:

Serializable, java.util.function.DoubleConsumer

@ThreadSafe
public final class LiveStats
extends Object
implements java.util.function.DoubleConsumer, Serializable

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
LiveStats(DecayConfig decayConfig, double... quantiles) Constructs a LiveStats object which will exponentially decay collected stats over time
LiveStats(double... quantiles) Constructs a LiveStats object which will track stats for all time

Method Summary

Modifier and Type	Method and Description
void	accept(double item) Adds another datum
void	add(double item) Adds another datum
void	decay()
void	decayByTime() Decays the currently recorded stats as much as they currently should be.
int	decayCount()
double	decayedMaximum() Gets the decayed maximum value of items so far added.
double	decayedMinimum() Gets the decayed minimum value of items so far added.
double	decayedNum()
double	kurtosis()
double	maximum()
double	mean()
double	minimum()
long	num()
Map<Double,Double>	quantiles()
double	skewness()
double	variance()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.function.DoubleConsumer

andThen

Constructor Detail

LiveStats

public LiveStats(double... quantiles)

Constructs a LiveStats object which will track stats for all time

Parameters:

quantiles - Quantiles to track (eg. .5 for the 50th percentile)

LiveStats

public LiveStats(DecayConfig decayConfig,
                 double... quantiles)

Constructs a LiveStats object which will exponentially decay collected stats over time

Parameters:

decayConfig - the configuration for time-based decay of statistics

quantiles - Quantiles to track (eg. .5 for the 50th percentile)

Method Detail

decayByTime

public void decayByTime()

Decays the currently recorded stats as much as they currently should be. The only time you need to call this directly is before reading stats. In general, it's called automatically as you add items.

decay

public void decay()

accept

public void accept(double item)

Adds another datum

Specified by:

accept in interface java.util.function.DoubleConsumer

Parameters:

item - the value to add

add

public void add(double item)

Adds another datum

Parameters:

item - the value to add

maximum

public double maximum()

Returns:

The maximum value.

decayedMaximum

public double decayedMaximum()

Gets the decayed maximum value of items so far added. This is not generally very useful, but could be used to drive some kind of peak meter or something. This value tends to jump around a lot as new maximums come in and decay periods hit.

Returns:

The decayed maximum.

mean

public double mean()

Returns:

The current decayed mean.

minimum

public double minimum()

Returns:

The maximum value.

decayedMinimum

public double decayedMinimum()

Gets the decayed minimum value of items so far added. This is not generally very useful, but could be used to drive some kind of peak meter or something. This value tends to jump around a lot as new minimums come in and decay periods hit.

Returns:

The decayed minimum.

num

public long num()

Returns:

The total number of items.

decayedNum

public double decayedNum()

Returns:

The approximate number of items counted in decayed stats.

decayCount

public int decayCount()

Returns:

The number of times that stats have been decayed.

quantiles

public Map<Double,Double> quantiles()

Returns:

Map of quantile to height

variance

public double variance()

Returns:

The current decayed variance.

kurtosis

public double kurtosis()

Returns:

The current decayed kurtosis.

skewness

public double skewness()

Returns:

The current decayed skewness.