Name

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      VARF

Purpose

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      Computes variance inside a moving window.

Category

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Calling Sequence

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      v = varf(x,w)

Inputs

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      x = array of input values. in
      w = width of window. in

Keyword Parameters

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Outputs

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      v = resulting variance array. out

Common Blocks

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Notes

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Notes: This filter may have problems if the variance
is small relative to the values in x. The performance
may be improved by subtracting the mean first:
v=varf(x-mean(x),w).

Modification History

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      Written by R. Sterner, 3 Jan, 1984.
R. Sterner, 25 Sep, 1991 --- added notes.
R. Sterner, 2008 Mar 31 --- Added _extra.
      Johns Hopkins University Applied Physics Laboratory.
  Copyright (C) 1984, Johns Hopkins University/Applied Physics Laboratory
  This software may be used, copied, or redistributed as long as it is not
  sold and this copyright notice is reproduced on each copy made. This
  routine is provided as is without any express or implied warranties
  whatsoever. Other limitations apply as described in the file disclaimer.txt.