Purpose

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  This procedure computes the Helmholz decomposition of a 3D vector
  field into its divergence and curl free components.

Inputs

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  x: The x component of the vector. A 3D array
  y: The y component of the vector. A 3D array
  z: The z component of the vector. A 3D array

Outputs

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  dx: The x component of the divergence-y (curl-free) term
  dy: The y component of the divergence-y (curl-free) term
  dz: The z component of the divergence-y (curl-free) term
  cx: The x component of the curly (divergence-free) term
  cy: The y component of the curly (divergence-free) term
  cz: The z component of the curly (divergence-free) term

Procedure

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  The input vector is projected into fourier space, and decomposed
  into modes parallel and perpendicular to k. These are then
  projected back into the original space, and are equal to the curl-
  and divergence-free vectors, respectively.

Modification History

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  2010-07-29: Created by Chris Beaumont