Package org.apache.commons.math4.transform

Enum FastFourierTransform.Norm

    • Enum Constant Detail

      • STD

        public static final FastFourierTransform.Norm STD
        Should be passed to the constructor of FastFourierTransform to use the standard normalization convention. This normalization convention is defined as follows
        • forward transform: \( y_n = \sum_{k = 0}^{N - 1} x_k e^{-2 \pi i n k / N} \),
        • inverse transform: \( x_k = \frac{1}{N} \sum_{n = 0}^{N - 1} y_n e^{2 \pi i n k / N} \),
        where \( N \) is the size of the data sample.

      • UNIT

        public static final FastFourierTransform.Norm UNIT
        Should be passed to the constructor of FastFourierTransform to use the unitary normalization convention. This normalization convention is defined as follows
        • forward transform: \( y_n = \frac{1}{\sqrt{N}} \sum_{k = 0}^{N - 1} x_k e^{-2 \pi i n k / N} \),
        • inverse transform: \( x_k = \frac{1}{\sqrt{N}} \sum_{n = 0}^{N - 1} y_n e^{2 \pi i n k / N} \),
        where \( N \) is the size of the data sample.

    • Method Detail

      • values

        public static FastFourierTransform.Norm[] values()
        Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows: 
        for (FastFourierTransform.Norm c : FastFourierTransform.Norm.values())
    System.out.println(c);
        Returns:
        an array containing the constants of this enum type, in the order they are declared

      • valueOf

        public static FastFourierTransform.Norm valueOf​(String name)
        Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
        Parameters:
        name - the name of the enum constant to be returned.
        Returns:
        the enum constant with the specified name
        Throws:
        IllegalArgumentException - if this enum type has no constant with the specified name
        NullPointerException - if the argument is null