lf34capr.m
computes the vector-leadfield relating sensor s and solution point d.
assuming that the external radio is one,
in an approximate way using the one shell model
using Berg parameters {EEG Journal 90 (1994) 58-64}.
s=(xs,ys,zs) sensor coordinates (electrode).
d=(xd,yd,zd) dipole coordinate or solution point.
lead=(lx,ly,lz) resulting components of the leadfield.
Models used
flag=1==> Cuffin and Cohen (1979) 4-shell model
flag=2==> Rush and Driscoll(1968) 3-shell model
flag=3==> Stok (1986) 4-shell model. Default model.
Conductivities order and radios from the outside to the inside.
3-shell model ==> { Scalp,Skull,Brain} 3 concentric spheres.
4-shell model ==> { Scalp,Skull,CSF,Brain} 4 concentric spheres.
uses lf1
rgpm 3-1-97.