CppAD: A C++ Algorithmic Differentiation Package
20171217


inline 
Reverse mode Hessian sparsity pattern for nonlinear unary operators.
The C++ source code corresponding to this operation is
z = fun(x)
where fun is a nonlinear functions; e.g. sin. or
z = q / x
where q is a parameter.
This routine is given the forward mode Jacobian sparsity patterns for x. It is also given the reverse mode dependence of G on z. In addition, it is given the revese mode Hessian sparsity for the quanity of interest G(z , y , ... ) and it uses them to compute the sparsity patterns for
H( x , w , u , ... ) = G[ z(x) , x , w , u , ... ]
Vector_set  is the type used for vectors of sets. It can be either sparse_pack or sparse_list. 
i_z  variable index corresponding to the result for this operation; i.e. the row index in sparsity corresponding to z. 
i_x  variable index corresponding to the argument for this operator; i.e. the row index in sparsity corresponding to x. 
rev_jacobian  rev_jacobian[i_z] is all false (true) if the Jacobian of G with respect to z must be zero (may be nonzero). rev_jacobian[i_x] is all false (true) if the Jacobian with respect to x must be zero (may be nonzero). On input, it corresponds to the function G, and on output it corresponds to the function H. 
for_jac_sparsity  The set with index i_x in for_jac_sparsity is the forward mode Jacobian sparsity pattern for the variable x. 
rev_hes_sparsity  The set with index i_z in in rev_hes_sparsity is the Hessian sparsity pattern for the fucntion G where one of the partials derivative is with respect to z. The set with index i_x in rev_hes_sparsity is the Hessian sparsity pattern where one of the partials derivative is with respect to x. On input, it corresponds to the function G, and on output it corresponds to the function H. 
Definition at line 189 of file sparse_unary_op.hpp.
Referenced by rev_hes_sweep().