Name

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  MGH_EXAMPLE_ROI

Purpose

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  What *is* an ROI anyway? And how do I make it line up with an
  image?
  In my experience IDL, is disturbingly vague about registration
  between images and vector elements. The developers obviously
  assume that you will always deal with images having large numbers
  of elements, where a mismatch of a pixel here or there doesn't
  matter much. But I often to deal with small data sets, and I find
  it makes a difference whether the position of pixel is taken to be
  its centre or one of its corners.
  In this example a simple ROI is set up and used to compute a mask.
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  This software is provided subject to the following conditions:
  1. NIWA makes no representations or warranties regarding the
    accuracy of the software, the use to which the software may
    be put or the results to be obtained from the use of the
    software. Accordingly NIWA accepts no liability for any loss
    or damage (whether direct of indirect) incurred by any person
    through the use of or reliance on the software.
  2. NIWA is to be acknowledged as the original author of the
    software where the software is used or presented in any form.
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Modification History

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  Mark Hadfield, 2001-06:
    Written.