FT_PREPARE_NEIGHBOURS
Note that this reference documentation is identical to the help that is displayed in MATLAB when you type “help ft_prepare_neighbours”.
FT_PREPARE_NEIGHBOURS finds the neighbours of the channels based on three different methods. Using the 'distance'-method, prepare_neighbours is based on a minimum neighbourhood distance (in cfg.neighbourdist). The 'triangulation'-method calculates a triangulation based on a two-dimenstional projection of the sensor position. The 'template'-method loads a default template for the given data type. prepare_neighbours should be verified using cfg.feedback ='yes' or by calling ft_neighbourplot The positions of the channel are specified in a gradiometer or electrode configuration or from a layout. The sensor configuration can be passed into this function in three ways: (1) in a configuration field, (2) in a file whose name is passed in a configuration field, and that can be imported using FT_READ_SENS, or (3) in a data field. Use as neighbours = ft_prepare_neighbours(cfg, data) The configuration can contain cfg.method = 'distance', 'triangulation' or 'template' cfg.neighbourdist = number, maximum distance between neighbouring sensors (only for 'distance') cfg.template = name of the template file, e.g. CTF275_neighb.mat cfg.layout = filename of the layout, see FT_PREPARE_LAYOUT cfg.channel = channels for which neighbours should be found cfg.feedback = 'yes' or 'no' (default = 'no') The EEG or MEG sensor positions can be present in the data or can be specified as cfg.elec = structure with electrode positions, see FT_DATATYPE_SENS cfg.grad = structure with gradiometer definition, see FT_DATATYPE_SENS cfg.elecfile = name of file containing the electrode positions, see FT_READ_SENS cfg.gradfile = name of file containing the gradiometer definition, see FT_READ_SENS The output is an array of structures with the "neighbours" which is structured like this: neighbours(1).label = 'Fz'; neighbours(1).neighblabel = {'Cz', 'F3', 'F3A', 'FzA', 'F4A', 'F4'}; neighbours(2).label = 'Cz'; neighbours(2).neighblabel = {'Fz', 'F4', 'RT', 'RTP', 'P4', 'Pz', 'P3', 'LTP', 'LT', 'F3'}; neighbours(3).label = 'Pz'; neighbours(3).neighblabel = {'Cz', 'P4', 'P4P', 'Oz', 'P3P', 'P3'}; etc. Note that a channel is not considered to be a neighbour of itself. See also FT_NEIGHBOURPLOT