FT_DATATYPE_RAW describes the FieldTrip MATLAB structure for raw data

 The raw datatype represents sensor-level time-domain data typically
 obtained after calling FT_DEFINETRIAL and FT_PREPROCESSING. It contains
 one or multiple segments of data, each represented as Nchan X Ntime
 arrays.

 An example of a raw data structure with 151 MEG channels is

          label: {151x1 cell}      the channel labels (e.g. 'MRC13')
           time: {1x266 cell}      the timeaxis [1*Ntime double] per trial
          trial: {1x266 cell}      the numeric data [151*Ntime double] per trial
     sampleinfo: [266x2 double]    the begin and endsample of each trial relative to the recording on disk
      trialinfo: [266x1 double]    optional trigger or condition codes for each trial
            hdr: [1x1 struct]      the full header information of the original dataset on disk
           grad: [1x1 struct]      information about the sensor array (for EEG it is called elec)
           cfg: [1x1 struct]       the configuration used by the function that generated this data structure

 Required fields:
   - time, trial, label

 Optional fields:
   - sampleinfo, trialinfo, grad, elec, opto, hdr, cfg

 Deprecated fields:
   - fsample

 Obsoleted fields:
   - offset

 Revision history:

 (2011/latest) The description of the sensors has changed, see FT_DATATYPE_SENS
 for further information.

 (2010v2) The trialdef field has been replaced by the sampleinfo and
 trialinfo fields. The sampleinfo corresponds to trl(:,1:2), the trialinfo
 to trl(4:end).

 (2010v1) In 2010/Q3 it shortly contained the trialdef field which was a copy
 of the trial definition (trl) is generated by FT_DEFINETRIAL.

 (2007) It used to contain the offset field, which correcponds to trl(:,3).
 Since the offset field is redundant with the time axis, the offset field is
 from now on not present any more. It can be recreated if needed.

 (2003) The initial version was defined

 See also FT_DATATYPE, FT_DATATYPE_COMP, FT_DATATYPE_TIMELOCK, FT_DATATYPE_FREQ,
 FT_DATATYPE_SPIKE, FT_DATATYPE_SENS