Package org.apache.sis.math

Class Plane.Fit

java.lang.Object

org.apache.sis.math.Plane.Fit

Enclosing class:

Plane

private static final class Plane.Fit
extends Object

Computes the plane coefficients. This class needs to iterate over the points two times: one for computing the coefficients, and one for the computing the Pearson coefficient. The second pass can also opportunistically checks if some small coefficients can be replaced by zero.

Field Summary

Fields

Modifier and Type	Field	Description
private final int	n
private final DoubleDouble	sum_x
private final DoubleDouble	sum_xx
private final DoubleDouble	sum_xy
private final DoubleDouble	sum_y
private final DoubleDouble	sum_yy
private final DoubleDouble	sum_z
private final DoubleDouble	sum_zx
private final DoubleDouble	sum_zy
(package private) DoubleDouble	sx	Solution of the plane equation.
(package private) DoubleDouble	sy	Solution of the plane equation.
private final DoubleDouble	xx
private final DoubleDouble	xy
private final DoubleDouble	yy
(package private) DoubleDouble	z0	Solution of the plane equation.
private final DoubleDouble	zx
private final DoubleDouble	zy

Constructor Summary

Constructors

Constructor	Description
Fit(int nx, int ny, Vector vz)	Computes the values of all sum_* fields from the z values on a regular grid.
Fit(Iterable<? extends org.opengis.geometry.DirectPosition> points)	Computes the values of all sum_* fields from randomly distributed points.

Method Summary

Modifier and Type	Method	Description
(package private) double	correlation(int nx, int length, Vector vz, Iterator<? extends org.opengis.geometry.DirectPosition> points)	Computes an estimation of the Pearson correlation coefficient.
private void	resolve()	Computes the sx, sy and Plane.z0() values using the sums computed by the constructor.

Methods inherited from class java.lang.Object

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

Field Details

sum_x

private final DoubleDouble sum_x

sum_y

private final DoubleDouble sum_y

sum_z

private final DoubleDouble sum_z

sum_xx

private final DoubleDouble sum_xx

sum_yy

private final DoubleDouble sum_yy

sum_xy

private final DoubleDouble sum_xy

sum_zx

private final DoubleDouble sum_zx

sum_zy

private final DoubleDouble sum_zy

xx

private final DoubleDouble xx

yy

private final DoubleDouble yy

xy

private final DoubleDouble xy

zx

private final DoubleDouble zx

zy

private final DoubleDouble zy

n

private final int n

sx

DoubleDouble sx

Solution of the plane equation.

sy

DoubleDouble sy

Solution of the plane equation.

z0

DoubleDouble z0

Solution of the plane equation.

Constructor Details

Fit

Fit(Iterable<? extends org.opengis.geometry.DirectPosition> points)

Computes the values of all sum_* fields from randomly distributed points. Value of all other fields are undetermined..

Fit

Fit(int nx,
 int ny,
 Vector vz)

Computes the values of all sum_* fields from the z values on a regular grid. Value of all other fields are undetermined..

Method Details

resolve

private void resolve()

Computes the sx, sy and Plane.z0() values using the sums computed by the constructor.

correlation

double correlation(int nx,
 int length,
 Vector vz,
 Iterator<? extends org.opengis.geometry.DirectPosition> points)

Computes an estimation of the Pearson correlation coefficient. We do not use double-double arithmetic here since the Pearson coefficient is for information purpose (quality estimation).

Only one of (nx, length, z) tuple or points argument should be non-null.