Create the advection constrain.
c = divand_constr_advec(s,velocity)
Create the advection constrain using the specified velocity.
Input:
s: structure created by divand_background
velocity: cell array of velocity vectors
Output:
c: structure to be used by divand_addc with the following fields: R (a
covariance matrix), H (extraction operator) and yo (specified value for
the constrain).
Package: divand