org.knime.base.util.math
Class StatisticUtils

java.lang.Object
  org.knime.base.util.math.StatisticUtils

public final class StatisticUtils
extends Object

Implements basic statistical functions.

Author:

Christoph Sieb, University of Konstanz

Method Summary

static double[][]	covariance(double[][] dataMatrix) Calculates the covariance matrix for the given input matrix.
static double[]	mean(double[][] matrix) Calculates the mean for each column of the given input matrix.
static double[]	standardDeviation(double[][] matrix) Calculates the standard deviation for each column of the given input matrix.
static double[]	variance(double[][] matrix) Calculates the variance for each column of the given input matrix.

Methods inherited from class java.lang.Object

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

Method Detail

covariance

public static double[][] covariance(double[][] dataMatrix)

Calculates the covariance matrix for the given input matrix.

Parameters:

dataMatrix - The input data matrix. The first dimension represents data rows, the second dimension the columns (attributes).

Returns:

the square covariance matrix

standardDeviation

public static double[] standardDeviation(double[][] matrix)

Calculates the standard deviation for each column of the given input matrix.

Parameters:

matrix - the input matrix

Returns:

an array with the standard deviation for each column

variance

public static double[] variance(double[][] matrix)

Calculates the variance for each column of the given input matrix.

Parameters:

matrix - the input matrix

Returns:

an array with the variance for each column

mean

public static double[] mean(double[][] matrix)

Calculates the mean for each column of the given input matrix.

Parameters:

matrix - the input matrix

Returns:

an array with the mean for each column