% Berechnungsmodell (Kreisringsegment):

ri   = 100 ; ra    = 120 ; alpha = 104.2 ;
nrad = 2 ; ntang = 20  ;
[ne , nk , xy , km , kr] = TorsArcnetD6 (ri , ra , alpha , nrad , ntang) ;
ep = [] ;
bk = zeros (nk,1) ;

drawtorsmod (xy , km , kr , bk) ;

% Finite-Elemente-Algorithmus:
[succ uv] = feskal_m (xy , km , ep , kr , bk) ;

% Torsions-Traegheitsmoment:
It = 0 ;
for i = 1:ne
    k1 = km(i,1) ;
    k2 = km(i,2) ;
    k3 = km(i,3) ;
    k4 = km(i,4) ;
    k5 = km(i,5) ;
    k6 = km(i,6) ;
    x1 = xy(k1,1) ;
    y1 = xy(k1,2) ;
    x2 = xy(k2,1) ;
    y2 = xy(k2,2) ;
    x3 = xy(k3,1) ;
    y3 = xy(k3,2) ;
    Ai = ((x2-x1)*(y3-y1)-(x3-x1)*(y2-y1)) * 0.5 ;
    It = It - (uv(k4) + uv(k5) + uv(k6)) * Ai ;
end

It = It*4/3
ItDurch_s_tHoch3 = It/(pi*alpha/180*(ra+ri)/2*(ra-ri)^3)