Purpose

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  This function appends a second array to a first one. It's
  only real convenience is that it handles the case when the first
  array is undefined.

Inputs

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  a: The first array. This need not be defined
  b: The second array, which must be defined

Outputs

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  The concatenation of a and b

Examples

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  a = [1,2,3]
  b = [4,5]
  print, append(a,b)
    [1,2,3,4,5]
  d = [6,7]
  print, append(not_defined, d)
    [6,7]

Modification History

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  April 2010: Written by Chris Beaumont