vb_dipole_gradio

 Magnetic field of Gradiometer 
   B = vb_dipole_gradio(V,J,pick, Qpick, Wsensor)
 --- INPUT
   Dipole current source
     V  : current dipole position   ( NP x 3 )
     J  : current dipole moment     ( NP x 3 )
   MEG sensor
  pick(n,1:3) : n-th coil position   [m]
 Qpick(n,1:3) : n-th coil direction 
 Wsensor(m,n) = n-th coil weight for m-th channel
    basis(channel,dipole) = Wsensor * basis(coil,dipole)
 --- OUTPUT
   B : Lead field matrix          ( NP x Nch )

   NP  : # of dipole points
   Nch : # of MEG sensor channel

 双極子磁場差分計算
 V の双極子 J が 観測点 pick1 と pick2 に作る磁場の差分の Q 方向射影

  Ver-2.0 2007-2-22 Made by M. Sato

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

0001 function    B = vb_dipole_gradio(V,J,pick, Qpick, Wsensor)
0002 % Magnetic field of Gradiometer
0003 %   B = vb_dipole_gradio(V,J,pick, Qpick, Wsensor)
0004 % --- INPUT
0005 %   Dipole current source
0006 %     V  : current dipole position   ( NP x 3 )
0007 %     J  : current dipole moment     ( NP x 3 )
0008 %   MEG sensor
0009 %  pick(n,1:3) : n-th coil position   [m]
0010 % Qpick(n,1:3) : n-th coil direction
0011 % Wsensor(m,n) = n-th coil weight for m-th channel
0012 %    basis(channel,dipole) = Wsensor * basis(coil,dipole)
0013 % --- OUTPUT
0014 %   B : Lead field matrix          ( NP x Nch )
0015 %
0016 %   NP  : # of dipole points
0017 %   Nch : # of MEG sensor channel
0018 %
0019 % 双極子磁場差分計算
0020 % V の双極子 J が 観測点 pick1 と pick2 に作る磁場の差分の Q 方向射影
0021 %
0022 %  Ver-2.0 2007-2-22 Made by M. Sato
0023 %
0024 % Copyright (C) 2011, ATR All Rights Reserved.
0025 % License : New BSD License(see VBMEG_LICENSE.txt)
0026 
0027 
0028 B   = vb_dipole_magnetic(V, J, pick, Qpick );
0029 % B : Lead field matrix          ( dipole x coil )
0030 
0031 B = B * Wsensor';
0032 
0033 %B   = vb_dipole_magnetic(V, J, pick1, pickv ) ...
0034 %    - vb_dipole_magnetic(V, J, pick2, pickv );