Note that this reference documentation is identical to the help that is displayed in MATLAB when you type “help ft_transform_sens”.

  FT_TRANSFORM_SENS applies a homogenous coordinate transformation to a
  structure with EEG electrodes or MEG gradiometers. For MEG gradiometers
  the homogenous transformation matrix should be limited to a rigid-body
  translation plus rotation.
 
  Use as
    sens = ft_transform_sens(transform, sens)
 
  See also FT_READ_SENS, FT_PREPARE_VOL_SENS, FT_COMPUTE_LEADFIELD