vb_load_basis

 Load leadfileld matrix.

 [syntax]
 [basis,Norient]=vb_load_basis(basisfile)

 [input]
 basisfile : <<string>> Leadfield file (.basis.mat)
 patch_norm: <optional> <<bool>> If true, leadfield is multiplied by patch area.
 brainfile : <optional> <<string>> Brain file, necessary if patch_norm is ON.

 [output]
 basis  : <<matrix>> Leadfield matrix.
  basis( Norient * Nvertex , Npick)
       basis( n, k )   : k-th sensor magnetic field for dipole current
       at n-th dipole.
 Norient: <<int>> Number of independent current orientation.

 2010-11-15 Taku Yoshioka
  Comment modified.
 2022-04-27 Y. Takeda
  Added option for patch_norm = ON

 Copyright (C) 2011, ATR All Rights Reserved.
 License : New BSD License(see VBMEG_LICENSE.txt)

0001 function [basis,Norient]=vb_load_basis(basisfile,patch_norm,brainfile);
0002 % Load leadfileld matrix.
0003 %
0004 % [syntax]
0005 % [basis,Norient]=vb_load_basis(basisfile)
0006 %
0007 % [input]
0008 % basisfile : <<string>> Leadfield file (.basis.mat)
0009 % patch_norm: <optional> <<bool>> If true, leadfield is multiplied by patch area.
0010 % brainfile : <optional> <<string>> Brain file, necessary if patch_norm is ON.
0011 %
0012 % [output]
0013 % basis  : <<matrix>> Leadfield matrix.
0014 %  basis( Norient * Nvertex , Npick)
0015 %       basis( n, k )   : k-th sensor magnetic field for dipole current
0016 %       at n-th dipole.
0017 % Norient: <<int>> Number of independent current orientation.
0018 %
0019 % 2010-11-15 Taku Yoshioka
0020 %  Comment modified.
0021 % 2022-04-27 Y. Takeda
0022 %  Added option for patch_norm = ON
0023 %
0024 % Copyright (C) 2011, ATR All Rights Reserved.
0025 % License : New BSD License(see VBMEG_LICENSE.txt)
0026 
0027 
0028 s = load(basisfile);
0029 
0030 % extra dipole basis
0031 if isfield(s, 'extra_basis_parm')
0032     Norient = 3;
0033     basis   = s.basis;
0034     return;
0035 else
0036 % basis
0037     Norient = s.basis_parm.Basis_mode;
0038 
0039     if exist('patch_norm', 'var') & patch_norm==ON,
0040         [tmp1,tmp2,tmp3,tmp4,xxA] = vb_load_cortex(brainfile, 'subj');
0041         S = repmat(xxA, Norient, size(s.basis, 2));
0042         basis = s.basis.*S;
0043     else
0044         basis = s.basis;
0045     end
0046 end
0047