phase_angle_data

 PHASE_ANGLE_DATA(data, chns, evt1, evt2) computes phase angle taking into
 account additional padding due to Hilbert Transform edge effects

 ARGUMENTS
   data        ... struct, zoo file to operate on
   chns        ... cell array strings, channels over which to compute phase angle
   evt1        ... string, name of first event where phase angle computation should start
   evt12       ... string, name of second event where phase angle computation should end
   pad_type    ... num, option to pad with zeros or Nans. Default is NaN
 
 RETURNS
   data        ... struct, zoo file with additonal phase angle channels added
                   as 'chns{i}_phase'