evaluate the sparse Hessian of the objective function and of the constraints of a given AMPL problem
W = ampl_eval_sp_w(asl, v)
the dual variables
a structure which handles the pointer to the problem
a matrix handling the Hessian (dimension: n_var x n_var)
Evaluate the sparse Hessian of the objective function and of the constraintsof a given AMPL problem. The Hessian is evaluated at the last point given to ampl_evalf.