yp = [ 
    S11*y(1)  + S12*y(2) + S13*y(3) + 0         + 0        + 0        + 0         + 0        + 0        + 0          + 0         + 0         + S_1*y(13)  + 0          + 0          + 0          + 0      
    S14*y(1)  + S15*y(2) + S16*y(3) + 0         + 0        + 0        + 0         + 0        + 0        + 0          + 0         + 0         + 0          + 0          + 0          + 0          + 0      
    S17*y(1)  + S18*y(2) + S19*y(3) + 0         + 0        + 0        + 0         + 0        + 0        + 0          + 0         + 0         + 0          + 0          + 0          + 0          + 0      
    0         + 0        + 0        + S21*y(4)  + S22*y(5) + S23*y(6) + 0         + 0        + 0        + 0          + 0         + 0         + 0          + S_1*y(14)  + 0          + 0          + 0      
    0         + 0        + 0        + S24*y(4)  + S25*y(5) + S26*y(6) + 0         + 0        + 0        + 0          + 0         + 0         + 0          + 0          + 0          + 0          + 0      
    0         + 0        + 0        + S27*y(4)  + S28*y(5) + S29*y(6) + 0         + 0        + 0        + 0          + 0         + 0         + 0          + 0          + 0          + 0          + 0      
    0         + 0        + 0        + 0         + 0        + 0        + S31*y(7)  + S32*y(8) + S33*y(9) + 0          + 0         + 0         + 0          + 0          + S_1*y(15)  + 0          + 0
    0         + 0        + 0        + 0         + 0        + 0        + S34*y(7)  + S35*y(8) + S36*y(9) + 0          + 0         + 0         + 0          + 0          + 0          + 0          + 0
    0         + 0        + 0        + 0         + 0        + 0        + S37*y(7)  + S38*y(8) + S39*y(9) + 0          + 0         + 0         + 0          + 0          + 0          + 0          + 0
    0         + 0        + 0        + 0         + 0        + 0        + 0         + 0        + 0        + S41*y(10)  + S42*y(11) + S43*y(12) + 0          + 0          + 0          + S_1*y(16)  + 0      
    0         + 0        + 0        + 0         + 0        + 0        + 0         + 0        + 0        + S44*y(10)  + S45*y(11) + S46*y(12) + 0          + 0          + 0          + 0          + 0      
    0         + 0        + 0        + 0         + 0        + 0        + 0         + 0        + 0        + S47*y(10)  + S48*y(11) + S49*y(12) + 0          + 0          + 0          + 0          + 0      
    NG11*y(1) + 0        + 0        + 0         + 0        + 0        + 0         + 0        + 0        + 0          + 0         + 0         + NG12*y(13) + 0          + 0          + 0          + (q1/CN1)
    0         + 0        + 0        + NG21*y(4) + 0        + 0        + 0         + 0        + 0        + 0          + 0         + 0         + 0          + NG22*y(14) + 0          + 0          + (q2/CN2)
    0         + 0        + 0        + 0         + 0        + 0        + NG31*y(7) + 0        + 0        + 0          + 0         + 0         + 0          + 0          + NG32*y(15) + 0          + (q3/CN3)
    0         + 0        + 0        + 0         + 0        + 0        + 0         + 0        + 0        + NG21*y(10) + 0         + 0         + 0          + 0          + 0          + NG42*y(16) + (q4/CN4)
] ;