d1dxqa_    d1dxqb_    d1dxqc_    d1dxqd_ 
d1dxqa_           0.0        0.0        0.0        0.0 
d1dxqb_           0.0        0.0        0.0        0.0 
d1dxqc_           0.0        0.0        0.0        0.0 
d1dxqd_           0.0        0.0        0.0        0.0