convIndex2Time

  convIndex2Time returns the sample time(s) of waveform elements

  Examples:
  Using indices
  time=convIndex2Time(channel, SampleNumber)
  or using subscripts:
  time=convIndex2Time(channel, Epoch, SampleNumberWithinEpoch)
  where:
  channel is a sigTOOL channel object

  When SampleNumber is supplied, this is the 1-D index into the channel adc
  field (adc need not be 1-dimensional so this method can be used
  regardless of the dimensions of the adc matrix).

  Alternatively, subscripts may be used where Epoch and 
  SampleNumberWithinEpoch are the subscripts of the element that the sample
  time is required for e.g. convIndex2Time(channel, 10, 8) returns the time
  of the 8th sample in epoch 10. This is limited to vectors and 2-D matrices.

  To convert between subscripts and indices use ind2sub and sub2ind

  See also convTime2ValidIndex, ind2sub, sub2ind

  SampleNumber, Epoch and SampleNumberWithinEpoch may be column vectors
  with multiple indices. In that case time will a vector of sample times.

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  Author: Malcolm Lidierth 09/06
  Copyright © The Author & King's College London 2006-7
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