Reference documentation for deal.II version 9.3.3

#include <deal.II/differentiation/ad/ad_helpers.h>
Public Types  
template<int , int dim, typename NumberType >  
using  type = SymmetricTensor< 4, dim, NumberType > 
An intermediate helper struct that defines the return type of Hessian (second derivative) calculations of scalar fields with respect to fields defined by the two extractortype template parameters. This particular specialization is for taking both the first and second derivatives with respect to symmetric tensor fields.
Definition at line 2271 of file ad_helpers.h.
using Differentiation::AD::internal::HessianType< FEValuesExtractors::SymmetricTensor< 2 >, FEValuesExtractors::SymmetricTensor< 2 > >::type = SymmetricTensor<4 , dim, NumberType> 
The type associated with computing the gradient of a scalar field with respect to the given ExtractorType_Row = FEValuesExtractors::SymmetricTensor<2>
followed by the ExtractorType_Col = FEValuesExtractors::SymmetricTensor<2>
.
Definition at line 2283 of file ad_helpers.h.