PCA

java.lang.Object
- jhplot.stat.PCA

```
public class PCA
extends Object
```
Perform a principle component analysis

Constructor Summary

Constructors
Constructor and Description

PCA(double[][] xy)
Initialize 2D PCA analysis

PCA(P1D p1d)
Perform PCA analysis using P1D object (in 2D).

Constructors
Constructor and Description
`PCA(double[][] xy)` Initialize 2D PCA analysis
`PCA(P1D p1d)` Perform PCA analysis using P1D object (in 2D).

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`double[][]`	`center_reduce(double[][] x)`
`void`	`doc()` Show online documentation.
`void`	`eval()`
`double`	`getCoordinate(int k, int i)` Positions of the last coordinates of the projection vectors (eigenvectors)
`double[][]`	`getCovariance()` Get covariance matrix
`double[]`	`getD()` Get transpose
`double`	`getEigenvalue(int k)` Information about eigenvalues
`double`	`getEigenvalueTot(int k)` Express eigenvalues as percentage of total
`double`	`getMean(int k)` Get means for the component k
`double`	`getStd(int k)` Get standard deviations
`String`	`getSummary()` Return projection vectors and information per projection vector.
`double[]`	`inv_center_reduce(double[] y)`
`double[][]`	`inv_center_reduce(double[][] y)`
`static void`	`main(String[] args)`

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - PCA
```
public PCA(double[][] xy)
```
    Initialize 2D PCA analysis
    
    Parameters:
    
    xy - array in X
  - PCA
```
public PCA(P1D p1d)
```
    Perform PCA analysis using P1D object (in 2D). All weights for points are set to 1. X and Y component of P1D are used for the PCA.
    
    Parameters:
    
    p1d - P1D input objects
- Method Detail
  - eval
```
public void eval()
```
  - center_reduce
```
public double[][] center_reduce(double[][] x)
```
  - inv_center_reduce
```
public double[] inv_center_reduce(double[] y)
```
  - inv_center_reduce
```
public double[][] inv_center_reduce(double[][] y)
```
  - getSummary
```
public String getSummary()
```
    Return projection vectors and information per projection vector.
    
    Returns:
    
    text
  - getEigenvalue
```
public double getEigenvalue(int k)
```
    Information about eigenvalues
    
    Parameters:
    
    k - - integer value (axis index of the projection)
    
    Returns:
  - getEigenvalueTot
```
public double getEigenvalueTot(int k)
```
    Express eigenvalues as percentage of total
    
    Parameters:
    
    k - integer value (axis index of the projection)
    
    Returns:
  - getCoordinate
```
public double getCoordinate(int k,
                            int i)
```
    Positions of the last coordinates of the projection vectors (eigenvectors)
    
    Parameters:
    
    k - - integer value (axis index)
    
    i - - index (position)
    
    Returns:
  - getCovariance
```
public double[][] getCovariance()
```
    Get covariance matrix
    
    Returns:
  - getD
```
public double[] getD()
```
    Get transpose
    
    Returns:
  - getMean
```
public double getMean(int k)
```
    Get means for the component k
    
    Parameters:
    
    k - index of the axis
    
    Returns:
  - getStd
```
public double getStd(int k)
```
    Get standard deviations
    
    Parameters:
    
    k - index of the axis
    
    Returns:
  - main
```
public static void main(String[] args)
```
  - doc
```
public void doc()
```
    Show online documentation.

Class PCA

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

PCA

PCA

Method Detail

eval

center_reduce

inv_center_reduce

inv_center_reduce

getSummary

getEigenvalue

getEigenvalueTot

getCoordinate

getCovariance

getD

getMean

getStd

main

doc