org.das2.qds.util

Class LinFit

java.lang.Object

org.das2.qds.util.LinFit

public class LinFit
extends java.lang.Object

Linear Fit routine. This will allow errors on the Y values, and will report chi squared. Borrowed from pamguard, https://sourceforge.net/projects/pamguard/.

Constructor Summary

Constructors

Constructor and Description
LinFit(QDataSet x, QDataSet y) do fit with uniform weights or weight=0 where fill is found.
LinFit(QDataSet x, QDataSet y, QDataSet sig) do fit with weights.

Method Summary

Modifier and Type	Method and Description
double	getA() return the result A, the intercept, of the fit y = A + B * x
double	getB() return the result B, the slope, of the fit y = A + B * x
double	getChi2() return the Chi-Squared result from the fit.
Datum	getIntercept() return the intercept (A of linear fit equation) as a datum with units of y.
double	getQ()
double	getSiga()
double	getSigb()
Datum	getSlope() return the slope (B of linear fit equation) as a datum with units of Yunits/Xunits.

Methods inherited from class java.lang.Object

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

Constructor Detail

LinFit

public LinFit(QDataSet x,
              QDataSet y)

do fit with uniform weights or weight=0 where fill is found.

Parameters:

x - the x data

y - the y data

LinFit

public LinFit(QDataSet x,
              QDataSet y,
              QDataSet sig)

do fit with weights. X and Y must not contain fill where sig>0.

Parameters:

x - the x data

y - the y data

sig - the error bar, or zero for fill.

Method Detail

getA

public double getA()

return the result A, the intercept, of the fit y = A + B * x

Returns:

the result A of the fit y = A + B * x

getB

public double getB()

return the result B, the slope, of the fit y = A + B * x

Returns:

the result B of the fit y = A + B * x

getSlope

public Datum getSlope()

return the slope (B of linear fit equation) as a datum with units of Yunits/Xunits. Note the current version of the library is unable to do many unit calculations.

Returns:

the slope as a Datum with units.

getIntercept

public Datum getIntercept()

return the intercept (A of linear fit equation) as a datum with units of y.

Returns:

getChi2

public double getChi2()

return the Chi-Squared result from the fit.

Returns:

the Chi-Squared result from the fit.

getQ

public double getQ()

getSiga

public double getSiga()

getSigb

public double getSigb()