[问题] 由L：=M5.Transpose(V55).V55；求coeff（L，M5），出错，为什么?请问谁知道？

[julixi]

由L：=M5.Transpose(V55).V55；求coeff（L，M5），出错，为什么?请问谁知道？
如题，已知：
V55 := Vector(3, {(1) = cos(q5)*(cos(q4)*((qp2+qp3)*r4-cos(q3)*cos(q2)*qp1*r3+sin(q3)*qp2*d3+sin(q3)*sin(q2)*qp1*r3)+sin(q4)*(qp1*(cos(q3)*sin(q2)+sin(q3)*cos(q2))*r4+qp1*(d2+d3*cos(q2))))-sin(q5)*(-sin(q3)*cos(q2)*qp1*r3-cos(q3)*qp2*d3-cos(q3)*sin(q2)*qp1*r3), (2) = -sin(q5)*(cos(q4)*((qp2+qp3)*r4-cos(q3)*cos(q2)*qp1*r3+sin(q3)*qp2*d3+sin(q3)*sin(q2)*qp1*r3)+sin(q4)*(qp1*(cos(q3)*sin(q2)+sin(q3)*cos(q2))*r4+qp1*(d2+d3*cos(q2))))-cos(q5)*(-sin(q3)*cos(q2)*qp1*r3-cos(q3)*qp2*d3-cos(q3)*sin(q2)*qp1*r3), (3) = -sin(q4)*((qp2+qp3)*r4-cos(q3)*cos(q2)*qp1*r3+sin(q3)*qp2*d3+sin(q3)*sin(q2)*qp1*r3)+cos(q4)*(qp1*(cos(q3)*sin(q2)+sin(q3)*cos(q2))*r4+qp1*(d2+d3*cos(q2)))})；
L：=M5.Transpose(V55).V55；
求coeff（L，M5）;
出错：Error, unable to compute coeff
为什么会是这样呢？有谁知道呢？请告知，谢谢！