org.tinfour.demo.utils

Class TabulatorDelta

java.lang.Object

org.tinfour.demo.utils.TabulatorDelta

public class TabulatorDelta
extends Object

Tabulates mean and variance for "delta" values obtained from tests in which the result is found by comparing an estimated value (such as an interpolation result) with a known or expected value. The tabulator collects sums using both the signed values of the deltas as well as the absolute values of the deltas. The Kahan Summation algorithm is used to provide extended precision when processing a very large number of samples.

Constructor Summary

Constructors

Constructor and Description
TabulatorDelta()

Method Summary

Modifier and Type	Method and Description
double	getMaxValue() Get the signed maximum value of the input samples
double	getMeanAbsValue() Get the mean of the absolute values of the input sample values.
double	getMinValue() Get the signed minimum value of the input samples
int	getNumberSamples() Gets the number of sample values passed into this instance of the tabulator.
double	getStdDevAbsValue() Get an unbiased estimate of the standard deviation of the population based on the tabulated samples.
double	getSumSignedValues() Gets the sum of the signed sample values as input into this tabulator.
void	summarize(PrintStream ps, String label) Print a summary of the mean, standard deviation, min, max, and sum of signed errors.
void	tabulate(double delta) Adds the specified delta value to the running tally of observed value.

Methods inherited from class java.lang.Object

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

Constructor Detail

TabulatorDelta

public TabulatorDelta()

Method Detail

tabulate

public void tabulate(double delta)

Adds the specified delta value to the running tally of observed value.

Parameters:

delta - a valid floating point value, NaN's are ignored.

summarize

public void summarize(PrintStream ps,
                      String label)

Print a summary of the mean, standard deviation, min, max, and sum of signed errors.

Parameters:

ps - the print stream to which output is to be streamed

label - a label for the beginning of the output line

getMeanAbsValue

public double getMeanAbsValue()

Get the mean of the absolute values of the input sample values.

Returns:

a valid floating point number, zero if no input has occurred.

getStdDevAbsValue

public double getStdDevAbsValue()

Get an unbiased estimate of the standard deviation of the population based on the tabulated samples.

Returns:

the standard deviation of the absolute values of the inputs.

getMinValue

public double getMinValue()

Get the signed minimum value of the input samples

Returns:

a valid floating point number

getMaxValue

public double getMaxValue()

Get the signed maximum value of the input samples

Returns:

a valid floating point number

getSumSignedValues

public double getSumSignedValues()

Gets the sum of the signed sample values as input into this tabulator. In practice, a sum with a large positive or negative value would mean that the process used to estimate values consistently overshot or undershot the actual value.

Returns:

the sum of the signed values.

getNumberSamples

public int getNumberSamples()

Gets the number of sample values passed into this instance of the tabulator.

Returns:

a positive, potentially zero value.