Class BicubicSplineFunction

java.lang.Object
org.apache.commons.math3.analysis.interpolation.BicubicSplineFunction
All Implemented Interfaces:
BivariateFunction

class BicubicSplineFunction extends Object implements BivariateFunction
2D-spline function.
  • Field Details

    • N

      private static final short N
      Number of points.
      See Also:
    • a

      private final double[][] a
      Coefficients
    • partialDerivativeX

      private final BivariateFunction partialDerivativeX
      First partial derivative along x.
    • partialDerivativeY

      private final BivariateFunction partialDerivativeY
      First partial derivative along y.
    • partialDerivativeXX

      private final BivariateFunction partialDerivativeXX
      Second partial derivative along x.
    • partialDerivativeYY

      private final BivariateFunction partialDerivativeYY
      Second partial derivative along y.
    • partialDerivativeXY

      private final BivariateFunction partialDerivativeXY
      Second crossed partial derivative.
  • Constructor Details

    • BicubicSplineFunction

      BicubicSplineFunction(double[] coeff)
      Simple constructor.
      Parameters:
      coeff - Spline coefficients.
    • BicubicSplineFunction

      BicubicSplineFunction(double[] coeff, boolean initializeDerivatives)
      Simple constructor.
      Parameters:
      coeff - Spline coefficients.
      initializeDerivatives - Whether to initialize the internal data needed for calling any of the methods that compute the partial derivatives this function.
  • Method Details

    • value

      public double value(double x, double y)
      Compute the value for the function.
      Specified by:
      value in interface BivariateFunction
      Parameters:
      x - Abscissa for which the function value should be computed.
      y - Ordinate for which the function value should be computed.
      Returns:
      the value.
    • apply

      private double apply(double[] pX, double[] pY, double[][] coeff)
      Compute the value of the bicubic polynomial.
      Parameters:
      pX - Powers of the x-coordinate.
      pY - Powers of the y-coordinate.
      coeff - Spline coefficients.
      Returns:
      the interpolated value.
    • partialDerivativeX

      public BivariateFunction partialDerivativeX()
      Returns:
      the partial derivative wrt x.
    • partialDerivativeY

      public BivariateFunction partialDerivativeY()
      Returns:
      the partial derivative wrt y.
    • partialDerivativeXX

      public BivariateFunction partialDerivativeXX()
      Returns:
      the second partial derivative wrt x.
    • partialDerivativeYY

      public BivariateFunction partialDerivativeYY()
      Returns:
      the second partial derivative wrt y.
    • partialDerivativeXY

      public BivariateFunction partialDerivativeXY()
      Returns:
      the second partial cross-derivative.