# nc_dqcdzeta_Sin_to_Sout

- Computes derivative matrix of
nc*dQ/dzeta

where Q is the induced velocity induced by bound surface Surf_in onto bound surface Surf_out. The panel normals of Surf_out are constant.

The input/output are: - Der_coll of size (Kout,3*Kzeta_out): derivative due to the movement of collocation point on Surf_out. - Der_vert of size:

(Kout,3*Kzeta_in) if Surf_in_bound is True

(Kout,3*Kzeta_bound_in) if Surf_in_bound is False; Kzeta_bound_in is

the number of vertices in the bound surface of whom Surf_out is the wake.

Note that: - if Surf_in_bound is False, only the TE movement contributes to Der_vert. - if Surf_in_bound is False, the allocation of Der_coll could be speed-up by scanning only the wake segments along the chordwise direction, as on the others the net circulation is null.