运行lingo程序出现unexpectedjacobian

model:

min=max(T1..T5);

n1*8+2*((k1-1)*3.2+4.8)/1.6*x1=T1;

n2*8+2*((k2-1)*3.2+4.8)/1.6*x2=T2;

n3*8+2*((k3-1)*3.2+4.8)/1.6*x3=T3;

n4*8+2*((k4-1)*3.2+4.8)/1.6*x4=T4;

n5*8+2*((k5-1)*3.2+4.8)/1.6*x5=T5;

k5=28;

@bnd(1,k1,k2);

@bnd(k1,k2,k3);

@bnd(k2,k3,k4);

@bnd(k3,k4,k5);

@gin(k1);@gin(k2);@gin(k3);@gin(k4);

n1=0.5*(k1-1);

n2=0.5*(k2-k1);

n3=0.5*(k3-k2);

n4=0.5*(k4-k3);

n5=0.5*(k5-k4);

x1=(k1-1)*100/18;

x2=(k2-k1)*100/18;

x3=(k3-k2)*100/18;

x4=(k4-k3)*100/18;

x5=(k5-k4)*100/18;

end