Purpose

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  This function calculates the divergence of a 1, 2, or 3-dimensional
  vector function sampled on a uniform grid.

Inputs

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  x: The x component of the vector field.
  y: The y component of the vector field. Optional
  z: The z component of the vector field. Optional

Keyword Parameters

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  order: The order of the lagrange interpolation polynomial to use
  when calculating derivatives. See pdiv.pro for details. Defaults to 1.

Outputs

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  An array of the same shape as data, giving the divergence at each
  point.

Modification History

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  2010-08-03: Written by Chris Beaumont