Package org.apache.sysds.runtime.matrix.data

Class LibMatrixFourier

java.lang.Object
org.apache.sysds.runtime.matrix.data.LibMatrixFourier
public class LibMatrixFourier extends Object

  • Constructor Details

    • LibMatrixFourier

      public LibMatrixFourier()

  • Method Details

    • fft

      public static MatrixBlock[] fft(MatrixBlock re, MatrixBlock im, int threads)
      Function to perform FFT for two given matrices. The first one represents the real values and the second one the imaginary values. The output also contains one matrix for the real and one for the imaginary values.
      Parameters:
      re - matrix object representing the real values
      im - matrix object representing the imaginary values
      threads - number of threads
      Returns:
      array of two matrix blocks

    • ifft

      public static MatrixBlock[] ifft(MatrixBlock re, MatrixBlock im, int threads)
      Function to perform IFFT for two given matrices. The first one represents the real values and the second one the imaginary values. The output also contains one matrix for the real and one for the imaginary values.
      Parameters:
      re - matrix object representing the real values
      im - matrix object representing the imaginary values
      threads - number of threads
      Returns:
      array of two matrix blocks

    • fft_linearized

      public static MatrixBlock[] fft_linearized(MatrixBlock re, MatrixBlock im, int threads)
      Function to perform FFT for each row of two given matrices. The first one represents the real values and the second one the imaginary values. The output also contains one matrix for the real and one for the imaginary values.
      Parameters:
      re - matrix object representing the real values
      im - matrix object representing the imaginary values
      threads - number of threads
      Returns:
      array of two matrix blocks

    • ifft_linearized

      public static MatrixBlock[] ifft_linearized(MatrixBlock re, MatrixBlock im, int threads)
      Function to perform IFFT for each row of two given matrices. The first one represents the real values and the second one the imaginary values. The output also contains one matrix for the real and one for the imaginary values.
      Parameters:
      re - matrix object representing the real values
      im - matrix object representing the imaginary values
      threads - number of threads
      Returns:
      array of two matrix blocks

    • fft

      public static void fft(double[] re, double[] im, int rows, int cols, int threads, boolean inclColCalc)
      Function to perform FFT for two given double arrays. The first one represents the real values and the second one the imaginary values. Both arrays get updated and contain the result.
      Parameters:
      re - array representing the real values
      im - array representing the imaginary values
      rows - number of rows
      cols - number of rows
      threads - number of threads
      inclColCalc - if true, fft is also calculated for each column, otherwise only for each row

    • ifft

      public static void ifft(double[] re, double[] im, int rows, int cols, int threads, boolean inclColCalc)
      Function to perform IFFT for two given double arrays. The first one represents the real values and the second one the imaginary values. Both arrays get updated and contain the result.
      Parameters:
      re - array representing the real values
      im - array representing the imaginary values
      rows - number of rows
      cols - number of rows
      threads - number of threads
      inclColCalc - if true, fft is also calculated for each column, otherwise only for each row

    • fft_one_dim

      public static void fft_one_dim(double[] re, double[] im, double[] re_inter, double[] im_inter, int start, int stop, int num, int minStep)
      Function to perform one-dimensional FFT for two given double arrays. The first one represents the real values and the second one the imaginary values. Both arrays get updated and contain the result.
      Parameters:
      re - array representing the real values
      im - array representing the imaginary values
      re_inter - array for the real values of intermediate results
      im_inter - array for the imaginary values of intermediate results
      start - start index (incl.)
      stop - stop index (excl.)
      num - number of values used for fft
      minStep - step size between values used for fft

    • isPowerOfTwo

      public static boolean isPowerOfTwo(int n)
      Function for checking whether the given integer is a power of two.
      Parameters:
      n - integer to check
      Returns:
      true if n is a power of two, false otherwise

    • fft

      public static MatrixBlock[] fft(MatrixBlock re, int threads)
      Function to perform FFT for a given matrix. The given matrix only represents real values. The output contains one matrix for the real and one for the imaginary values.
      Parameters:
      re - matrix object representing the real values
      threads - number of threads
      Returns:
      array of two matrix blocks

    • ifft

      public static MatrixBlock[] ifft(MatrixBlock re, int threads)
      Function to perform IFFT for a given matrix. The given matrix only represents real values. The output contains one matrix for the real and one for the imaginary values.
      Parameters:
      re - matrix object representing the real values
      threads - number of threads
      Returns:
      array of two matrix blocks

    • fft_linearized

      public static MatrixBlock[] fft_linearized(MatrixBlock re, int threads)
      Function to perform FFT for each row of a given matrix. The given matrix only represents real values. The output contains one matrix for the real and one for the imaginary values.
      Parameters:
      re - matrix object representing the real values
      threads - number of threads
      Returns:
      array of two matrix blocks

    • ifft_linearized

      public static MatrixBlock[] ifft_linearized(MatrixBlock re, int threads)
      Function to perform IFFT for each row of a given matrix. The given matrix only represents real values. The output contains one matrix for the real and one for the imaginary values.
      Parameters:
      re - matrix object representing the real values
      threads - number of threads
      Returns:
      array of two matrix blocks