SONFActive

  SONFACTIVE tests filter mask layers to see if they are active

  Implemented through SONFActive.dll

  ANS=SONFActive(FilterMask)

  Bits 0 to 3 are set in ANS if filter mask layers 0 to 3 are active.

  Author:Malcolm Lidierth
  Matlab SON library:
  Copyright © The Author & King's College London 2005-2006