Class BicubicSplineFunction

    • Field Detail

      • 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 Detail

      • 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 Detail

      • 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.