Module imagingbook.common
Package imagingbook.common.geometry.fitting.line

Class LinearRegressionFit

java.lang.Object
imagingbook.common.geometry.fitting.line.LinearRegressionFit
All Implemented Interfaces:
LineFit
public class LinearRegressionFit extends Object implements LineFit

This class implements line fitting by linear regression to a set of 2D points. See Sec. 10.2.1 of [1] for additional details.

[1] W. Burger, M.J. Burge, Digital Image Processing – An Algorithmic Introduction, 3rd ed, Springer (2022).

Version:
2022/09/29

  • Constructor Summary

    Constructors
    Constructor
    Description
    LinearRegressionFit(Pnt2d[] points)
    Constructor, performs a linear regression fit to the specified points.

  • Method Summary

    Modifier and Type
    Method
    Description
    double
    getD()
    Returns the intercept parameter d for the fitted line y = k * x + d.
    double
    getK()
    Returns the slope parameter k for the fitted line y = k * x + d.
    double[]
    getLineParameters()
    Returns the parameters [A, B, C] for the AlgebraicLine associated with this line fit.
    int
    getSize()
    Returns the size of the point set used for calculating this line fit.
    double
    getSquaredRegressionError(Pnt2d[] points)
    Calculates and returns the sum of the squared differences between the y-coordinates of the data points (xi, yi) and the associated y-value of the regression line (y = k x + d).

    Methods inherited from class java.lang.Object

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

    Methods inherited from interface imagingbook.common.geometry.fitting.line.LineFit

    getLine, getSquaredOrthogonalError

  • Constructor Details

    • LinearRegressionFit

      public LinearRegressionFit(Pnt2d[] points)
      Constructor, performs a linear regression fit to the specified points. At least two different points are required.
      Parameters:
      points - an array with at least 2 points

  • Method Details

    • getSize

      public int getSize()
      Description copied from interface: LineFit
      Returns the size of the point set used for calculating this line fit.
      Specified by:
      getSize in interface LineFit
      Returns:
      the number of sample points used for fitting

    • getLineParameters

      public double[] getLineParameters()
      Description copied from interface: LineFit
      Returns the parameters [A, B, C] for the AlgebraicLine associated with this line fit. To be implemented by concrete classes. null is returned if no fit was found.
      Specified by:
      getLineParameters in interface LineFit
      Returns:
      algebraic line parameters [A, B, C]
      See Also:

    • getK

      public double getK()
      Returns the slope parameter k for the fitted line y = k * x + d.
      Returns:
      line parameter k

    • getD

      public double getD()
      Returns the intercept parameter d for the fitted line y = k * x + d.
      Returns:
      line parameter d

    • getSquaredRegressionError

      public double getSquaredRegressionError(Pnt2d[] points)
      Calculates and returns the sum of the squared differences between the y-coordinates of the data points (xi, yi) and the associated y-value of the regression line (y = k x + d).
      Parameters:
      points - an array of 2D points
      Returns:
      the squared regression error