Package ffx.numerics.fft

Class Complex3D

java.lang.Object
ffx.numerics.fft.Complex3D
public class Complex3D extends Object
Compute the 3D FFT of complex, double precision input of arbitrary dimensions via 1D Mixed Radix FFTs.

For interleaved data, the location of the input point [x, y, z] within the input array must be:
double real = input[x*nextX + y*nextY + z*nextZ]
double imag = input[x*nextX + y*nextY + z*nextZ + 1]
where
int nextX = 2
int nextY = 2*nX
int nextZ = 2*nX*nY

For blocked data along x, the location of the input point [x, y, z] within the input array must be:
double real = input[x*nextX + y*nextY + z*nextZ]
double imag = input[x*nextX + y*nextY + z*nextZ + im]
where
int nextX = 1
int nextY = 2*nX
int nextZ = 2*nX*nY
int im = nX for BLOCKED_X
int im = nX*nY for BLOCKED_XY
int im = nX*nY*nZ for BLOCKED_XYZ

Since:
1.0
Author:
Michal J. Schnieders
See Also:

  • Constructor Summary

    Constructors
    Constructor
    Description
    Complex3D(int nX, int nY, int nZ)
    Initialize the 3D FFT for complex 3D matrix using interleaved data layout.
    Complex3D(int nX, int nY, int nZ, DataLayout3D layout)
    Initialize the 3D FFT for complex 3D matrix.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    convolution(double[] input)
    Perform a convolution.
    void
    fft(double[] input)
    Compute the 3D FFT.
    void
    ifft(double[] input)
    Compute the inverse 3D FFT.
    static int
    index3D(int i, int j, int k, int nX, int nY, DataLayout3D layout)
    Determine the index of the complex number in the blocked 1D array from the X, Y and Z indices.
    static int
    interleavedIndex(int i, int j, int k, int nX, int nY)
    Determine the index of the complex number in the 1D array from the X, Y and Z indices.
    void
    setPackFFTs(boolean packFFTs)
    Set the 2D transform to pack FFTs.
    void
    setRecip(double[] recip)
    Setter for the field recip.
    void
    setUseSIMD(boolean useSIMD)
    Set the 2D transform to use SIMD instructions.

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • Complex3D

      public Complex3D(int nX, int nY, int nZ)
      Initialize the 3D FFT for complex 3D matrix using interleaved data layout.
      Parameters:
      nX - X-dimension.
      nY - Y-dimension.
      nZ - Z-dimension.

    • Complex3D

      public Complex3D(int nX, int nY, int nZ, DataLayout3D layout)
      Initialize the 3D FFT for complex 3D matrix.
      Parameters:
      nX - X-dimension.
      nY - Y-dimension.
      nZ - Z-dimension.
      layout - Data layout.

  • Method Details

    • setUseSIMD

      public void setUseSIMD(boolean useSIMD)
      Set the 2D transform to use SIMD instructions.
      Parameters:
      useSIMD - True to use SIMD instructions.

    • setPackFFTs

      public void setPackFFTs(boolean packFFTs)
      Set the 2D transform to pack FFTs.
      Parameters:
      packFFTs - True to pack FFTs.

    • interleavedIndex

      public static int interleavedIndex(int i, int j, int k, int nX, int nY)
      Determine the index of the complex number in the 1D array from the X, Y and Z indices.
      Parameters:
      i - the index along the X-axis.
      j - the index along the Y-axis.
      k - the index along the Z-axis.
      nX - the number of points along the X-axis.
      nY - the number of points along the Y-axis.
      Returns:
      the index of the complex number in the 1D array.

    • index3D

      public static int index3D(int i, int j, int k, int nX, int nY, DataLayout3D layout)
      Determine the index of the complex number in the blocked 1D array from the X, Y and Z indices.
      Parameters:
      i - the index along the X-axis.
      j - the index along the Y-axis.
      k - the index along the Z-axis.
      nX - the number of points along the X-axis.
      nY - the number of points along the Y-axis.
      layout - the data layout.
      Returns:
      the index of the complex number in the 1D array using blocked data layout.

    • fft

      public void fft(double[] input)
      Compute the 3D FFT.
      Parameters:
      input - The input array must be of size 2 * nX * nY * nZ.

    • ifft

      public void ifft(double[] input)
      Compute the inverse 3D FFT.
      Parameters:
      input - The input array must be of size 2 * nX * nY * nZ.

    • convolution

      public void convolution(double[] input)
      Perform a convolution.
      Parameters:
      input - The input array.

    • setRecip

      public void setRecip(double[] recip)
      Setter for the field recip.
      Parameters:
      recip - an array of double.