Compute MNI talairach coordinates from RAS coords.
ras.to.talairachras(ras_coords, talairach, invert_transform = FALSE)
the Talairach RAS coordinates for the given RAS coordinates
nx3 numerical vector, the input surface RAS coordinates. Could be the vertex coordinates of an 'fs.surface' instance, or the RAS coords from a surface label.
the 4x4 numerical talairach matrix, or a character string which will be interpreted as the path to an xfm file containing the matrix (typically `$SUBJECTS_DIR/$subject/mri/transforms/talairach.xfm`).
logical, whether to invert the transform. Do not use this, call link{talairachras.to.ras}
instead.