Purpose

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  This function computes the rank of each element in a data set. By default,
  The rank 0 element is the smallest element, the rank 1 element is
  second smallest, etc. If decrease keyword is set, the rank 0 element is
  the largest element.

Inputs

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  data: An array of numbers

Outputs

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  An array the same size as data, giving the rank of each element.

Keywords

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  decrease: set it if ranked in decrease order.

Modification History

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  2010-08-03: Written by Chris Beaumont