FieldTrip

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

  FT_PREPARE_LAYOUT creates a 2-D layout of the channel locations. This layout
  is required for plotting the topographical distribution of the potential
  or field distribution, or for plotting timecourses in a topographical
  arrangement.
  
  Use as
    lay = ft_prepare_layout(cfg, data)
 
  There are several ways in which a 2-D layout can be made: it can be read
  directly from a *.lay file, it can be created based on 3-D electrode or
  gradiometer positions in the configuration or in the data, or it can be
  created based on the specification of an electrode of gradiometer file.
 
  You can specify either one of the following configuration options
    cfg.layout      filename containg the layout
    cfg.rotate      number, rotation around the z-axis in degrees (default = [], which means automatic)
    cfg.projection  string, 2D projection method can be 'stereographic', 'orthographic', 'polar', 'gnomic' or 'inverse' (default = 'polar')
    cfg.elec        structure with electrode positions, or
    cfg.elecfile    filename containing electrode positions
    cfg.grad        structure with gradiometer definition, or
    cfg.gradfile    filename containing gradiometer definition
    cfg.output      filename to which the layout will be written (default = [])
    cfg.montage     'no' or a montage structure (default = 'no')
    cfg.image       filename, use an image to construct a layout (e.g. usefull for ECoG grids)
    cfg.bw          if an image is used and bw = 1 transforms the image in black and white (default = 0, do not transform)
 
  Alternatively the layout can be constructed from either
    data.elec     structure with electrode positions
    data.grad     structure with gradiometer definition
 
  Alternatively you can specify the following layouts which will be
  generated for all channels present in the data. Note that these layouts
  are suitable for multiplotting, but not for topoplotting.
    cfg.layout = 'ordered'  will give you a NxN ordered layout
    cfg.layout = 'vertical' will give you a Nx1 ordered layout
    cfg.layout = 'butterfly'  will give you a layout with all channels on top of each other
  
  The output layout structure will contain the following fields
    lay.label   = Nx1 cell-array with channel labels
    lay.pos     = Nx2 matrix with channel positions
    lay.width   = Nx1 vector with the width of each box for multiplotting
    lay.height  = Nx1 matrix with the height of each box for multiplotting
    lay.height  = Nx1 matrix with the height of each box for multiplotting
    lay.mask    = optional cell-array with line segments that determine the area for topographic interpolation
    lay.outline = optional cell-array with line segments that represent the head, nose, ears, sulci or other anatomical features
 
  See also FT_LAYOUTPLOT, FT_TOPOPLOTER, FT_TOPOPLOTTFR, FT_MULTIPLOTER, FT_MULTIPLOTTFR