com.pervasive.datarush.analytics.functions

Class StatsFunctions

java.lang.Object

com.pervasive.datarush.analytics.functions.StatsFunctions

public class StatsFunctions
extends Object

Useful statistics related functions.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	StatsFunctions.NormalizeMethod Supported methods of value normalization.

Method Summary

Modifier and Type	Method and Description
static ScalarValuedFunction	minmax(ScalarValuedFunction expr, BigDecimal min, BigDecimal max) Create a MinMax normalization function for the given subexpression.
static ScalarValuedFunction	minmax(ScalarValuedFunction expr, double min, double max) Create a MinMax normalization function for the given subexpression.
static ScalarValuedFunction	minmax(String field, BigDecimal min, BigDecimal max) Create a MinMax normalization function for the input field.
static ScalarValuedFunction	minmax(String field, double min, double max) Create a MinMax normalization function for the input field.
static ScalarValuedFunction	normalizeFunction(StatsFunctions.NormalizeMethod method, ScalarValuedFunction expr, AbstractNumericInfo<?> numInfo) Create a normalization function for the given function expression.
static ScalarValuedFunction	normalizeFunction(StatsFunctions.NormalizeMethod method, String field, AbstractNumericInfo<?> numInfo) Create a normalization function for the given input field.
static ScalarValuedFunction	zscore(ScalarValuedFunction expr, BigDecimal mean, BigDecimal stddev) Create a Z-Score normalization function for the given input function.
static ScalarValuedFunction	zscore(ScalarValuedFunction expr, double mean, double stddev) Create a Z-Score normalization function for the given input function.
static ScalarValuedFunction	zscore(String field, BigDecimal mean, BigDecimal stddev) Create a Z-Score normalization function for the input field.
static ScalarValuedFunction	zscore(String field, double mean, double stddev) Create a Z-Score normalization function for the input field.

Methods inherited from class java.lang.Object

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

Method Detail

normalizeFunction

public static ScalarValuedFunction normalizeFunction(StatsFunctions.NormalizeMethod method,
                                                     String field,
                                                     AbstractNumericInfo<?> numInfo)

Create a normalization function for the given input field.

Parameters:

method - the method to use

field - input field to normalize

numInfo - numerical statistics of the input field

Returns:

normalization function

normalizeFunction

public static ScalarValuedFunction normalizeFunction(StatsFunctions.NormalizeMethod method,
                                                     ScalarValuedFunction expr,
                                                     AbstractNumericInfo<?> numInfo)

Create a normalization function for the given function expression.

Parameters:

method - the method to use

expr - apply normalization to the result of this function

numInfo - numerical statistics of the input field

Returns:

normalization function

zscore

public static ScalarValuedFunction zscore(String field,
                                          double mean,
                                          double stddev)

Create a Z-Score normalization function for the input field.

Parameters:

field - input field to normalize

mean - mean of the input data

stddev - standard deviation of the input data

Returns:

normalization function

zscore

public static ScalarValuedFunction zscore(ScalarValuedFunction expr,
                                          double mean,
                                          double stddev)

Create a Z-Score normalization function for the given input function.

Parameters:

expr - apply normalization to the result of this function

mean - mean of the input data

stddev - standard deviation of the input data

Returns:

normalization function

zscore

public static ScalarValuedFunction zscore(String field,
                                          BigDecimal mean,
                                          BigDecimal stddev)

Create a Z-Score normalization function for the input field.

Parameters:

field - input field to normalize

mean - mean of the input data

stddev - standard deviation of the input data

Returns:

normalization function

zscore

public static ScalarValuedFunction zscore(ScalarValuedFunction expr,
                                          BigDecimal mean,
                                          BigDecimal stddev)

Create a Z-Score normalization function for the given input function.

Parameters:

expr - apply normalization to the result of this function

mean - mean of the input data

stddev - standard deviation of the input data

Returns:

normalization function

minmax

public static ScalarValuedFunction minmax(String field,
                                          double min,
                                          double max)

Create a MinMax normalization function for the input field.

Parameters:

field - input field to normalize

min - minimum value of the input data

max - maximum value of the input data

Returns:

normalization function

minmax

public static ScalarValuedFunction minmax(ScalarValuedFunction expr,
                                          double min,
                                          double max)

Create a MinMax normalization function for the given subexpression.

Parameters:

expr - apply normalization to the result of this function

min - minimum value of the input data

max - maximum value of the input data

Returns:

normalization function

minmax

public static ScalarValuedFunction minmax(String field,
                                          BigDecimal min,
                                          BigDecimal max)

Create a MinMax normalization function for the input field.

Parameters:

field - input field to normalize

min - minimum value of the input data

max - maximum value of the input data

Returns:

normalization function

minmax

public static ScalarValuedFunction minmax(ScalarValuedFunction expr,
                                          BigDecimal min,
                                          BigDecimal max)

Create a MinMax normalization function for the given subexpression.

Parameters:

expr - apply normalization to the result of this function

min - minimum value of the input data

max - maximum value of the input data

Returns:

normalization function