Reference documentation for deal.II version 9.2.0
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#include <deal.II/differentiation/ad/ad_helpers.h>
Public Types | |
using | scalar_type = typename HelperBase< ADNumberTypeCode, ScalarType >::scalar_type |
using | ad_type = typename HelperBase< ADNumberTypeCode, ScalarType >::ad_type |
Public Types inherited from Differentiation::AD::HelperBase< ADNumberTypeCode, double > | |
using | scalar_type = typename AD::NumberTraits< double, ADNumberTypeCode >::scalar_type |
using | ad_type = typename AD::NumberTraits< double, ADNumberTypeCode >::ad_type |
Public Member Functions | |
Constructor / destructor | |
PointLevelFunctionsBase (const unsigned int n_independent_variables, const unsigned int n_dependent_variables) | |
virtual | ~PointLevelFunctionsBase ()=default |
Operations specific to taped mode: Reusing tapes | |
void | set_independent_variables (const std::vector< scalar_type > &values) |
template<typename ValueType , typename ExtractorType > | |
void | set_independent_variable (const ValueType &value, const ExtractorType &extractor) |
Public Member Functions inherited from Differentiation::AD::HelperBase< ADNumberTypeCode, double > | |
HelperBase (const unsigned int n_independent_variables, const unsigned int n_dependent_variables) | |
virtual | ~HelperBase ()=default |
std::size_t | n_independent_variables () const |
std::size_t | n_dependent_variables () const |
void | print (std::ostream &stream) const |
void | print_values (std::ostream &stream) const |
void | print_tape_stats (const typename Types< ad_type >::tape_index tape_index, std::ostream &stream) const |
bool | is_recording () const |
Types< ad_type >::tape_index | active_tape_index () const |
bool | is_registered_tape (const typename Types< ad_type >::tape_index tape_index) const |
void | set_tape_buffer_sizes (const typename Types< ad_type >::tape_buffer_sizes obufsize=64 *1024 *1024, const typename Types< ad_type >::tape_buffer_sizes lbufsize=64 *1024 *1024, const typename Types< ad_type >::tape_buffer_sizes vbufsize=64 *1024 *1024, const typename Types< ad_type >::tape_buffer_sizes tbufsize=64 *1024 *1024) |
bool | start_recording_operations (const typename Types< ad_type >::tape_index tape_index, const bool overwrite_tape=false, const bool keep_independent_values=true) |
void | stop_recording_operations (const bool write_tapes_to_file=false) |
void | activate_recorded_tape (const typename Types< ad_type >::tape_index tape_index) |
bool | recorded_tape_requires_retaping (const typename Types< ad_type >::tape_index tape_index) const |
bool | active_tape_requires_retaping () const |
void | clear_active_tape () |
Static Public Attributes | |
static const unsigned int | dimension = dim |
Independent variables | |
std::vector< bool > | symmetric_independent_variables |
virtual void | reset (const unsigned int n_independent_variables=::numbers::invalid_unsigned_int, const unsigned int n_dependent_variables=::numbers::invalid_unsigned_int, const bool clear_registered_tapes=true) override |
void | register_independent_variables (const std::vector< scalar_type > &values) |
template<typename ValueType , typename ExtractorType > | |
void | register_independent_variable (const ValueType &value, const ExtractorType &extractor) |
const std::vector< ad_type > & | get_sensitive_variables () const |
template<typename ExtractorType > | |
internal::Extractor< dim, ExtractorType >::template tensor_type< ad_type > | get_sensitive_variables (const ExtractorType &extractor) const |
void | set_sensitivity_value (const unsigned int index, const bool symmetric_component, const scalar_type &value) |
bool | is_symmetric_independent_variable (const unsigned int index) const |
unsigned int | n_symmetric_independent_variables () const |
A base helper class that facilitates the evaluation of point-wise defined functions. This is the point-wise counterpart of the CellLevelBase class, and was conceived for computations at a continuum point, or quadrature point, rather than for finite-element level calculations. That being said, the interface to this and the derived classes are sufficiently generic that the dependent function(s) and their argument(s), that are the independent variables, can be interpreted in any manner that the user may choose.
As it offers a field-based interface, this class would typically be used to compute the derivatives of a constitutive law defined at a quadrature point; however, it may also be used in other contexts, such as to compute the linearization of a set of local nonlinear equations.
Definition at line 2640 of file ad_helpers.h.
using Differentiation::AD::PointLevelFunctionsBase< dim, ADNumberTypeCode, ScalarType >::scalar_type = typename HelperBase<ADNumberTypeCode, ScalarType>::scalar_type |
Type definition for the floating point number type that is used in, and results from, all computations.
Definition at line 2655 of file ad_helpers.h.
using Differentiation::AD::PointLevelFunctionsBase< dim, ADNumberTypeCode, ScalarType >::ad_type = typename HelperBase<ADNumberTypeCode, ScalarType>::ad_type |
Type definition for the auto-differentiation number type that is used in all computations.
Definition at line 2662 of file ad_helpers.h.
Differentiation::AD::PointLevelFunctionsBase< dim, ADNumberTypeCode, ScalarType >::PointLevelFunctionsBase | ( | const unsigned int | n_independent_variables, |
const unsigned int | n_dependent_variables | ||
) |
The constructor for the class.
[in] | n_independent_variables | The number of independent variables that will be used in the definition of the functions that it is desired to compute the sensitivities of. In the computation of \(\mathbf{f}(\mathbf{X})\), this will be the number of inputs \(\mathbf{X}\), i.e., the dimension of the domain space. |
[in] | n_dependent_variables | The number of scalar functions to be defined that will have a sensitivity to the given independent variables. In the computation of \(\mathbf{f}(\mathbf{X})\), this will be the number of outputs \(\mathbf{f}\), i.e., the dimension of the image space. |
Definition at line 1160 of file ad_helpers.cc.
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virtualdefault |
Destructor
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overridevirtual |
Reset the state of the helper class.
When an instance of an HelperBase is stored as a class member object with the intention to reuse its instance, it may be necessary to reset the state of the object before use. This is because, internally, there is error checking performed to ensure that the correct auto-differentiable data is being tracked and used only when appropriate. This function clears all member data and, therefore, allows the state of all internal flags to be safely reset to their initial state.
In the rare case that the number of independent or dependent variables has changed, this can also reconfigured by passing in the appropriate arguments to the function.
[in] | n_independent_variables | The number of independent variables that will be used in the definition of the functions that it is desired to compute the sensitivities of. In the computation of \(\mathbf{f}(\mathbf{X})\), this will be the number of inputs \(\mathbf{X}\), i.e., the dimension of the domain space. |
[in] | n_dependent_variables | The number of scalar functions to be defined that will have a sensitivity to the given independent variables. In the computation of \(\mathbf{f}(\mathbf{X})\), this will be the number of outputs \(\mathbf{f}\), i.e., the dimension of the image space. |
[in] | clear_registered_tapes | A flag that indicates the that list of registered_tapes must be cleared. If set to true then the data structure that tracks which tapes have been recorded is cleared as well. It is then expected that any preexisting tapes be re-recorded. |
Reimplemented from Differentiation::AD::HelperBase< ADNumberTypeCode, double >.
Definition at line 1173 of file ad_helpers.cc.
void Differentiation::AD::PointLevelFunctionsBase< dim, ADNumberTypeCode, ScalarType >::register_independent_variables | ( | const std::vector< scalar_type > & | values | ) |
Register the complete set of independent variables \(\mathbf{X}\).
[in] | values | A field that defines the values of all independent variables. When considering taped AD numbers with branching functions, to avoid potential issues with branch switching it may be a good idea to choose these values close or equal to those that will be later evaluated and differentiated around. |
scalar_type
. Depending on the selected ADNumberTypeCode
, this may or may not correspond with the ScalarType
prescribed as a template argument.Definition at line 1225 of file ad_helpers.cc.
void Differentiation::AD::PointLevelFunctionsBase< dim, ADNumberTypeCode, ScalarType >::register_independent_variable | ( | const ValueType & | value, |
const ExtractorType & | extractor | ||
) |
Register the subset of independent variables \(\mathbf{A} \subset \mathbf{X}\).
[in] | value | A field that defines a number of independent variables. When considering taped AD numbers with branching functions, to avoid potential issues with branch switching it may be a good idea to choose these values close or equal to those that will be later evaluated and differentiated around. |
[in] | extractor | An extractor associated with the input field variables. This effectively defines which components of the global set of independent variables this field is associated with. |
scalar_type
. Depending on the selected ADNumberTypeCode
, this may or may not correspond with the ScalarType
prescribed as a template argument.ValueType
. So, for example, if a value is a rank-1 tensor (i.e. of type Tensor<1,dim,scalar_type>), then the extractor must be an FEValuesExtractors::Vector or FEValuesExtractors::Tensor<1>.const std::vector< typename PointLevelFunctionsBase< dim, ADNumberTypeCode, ScalarType >::ad_type > & Differentiation::AD::PointLevelFunctionsBase< dim, ADNumberTypeCode, ScalarType >::get_sensitive_variables |
Return the complete set of independent variables as represented by auto-differentiable numbers. These are the independent variables \(\mathbf{X}\) at which the dependent values are evaluated and differentiated.
This function indicates to the AD library that implements the auto-differentiable number type that operations performed on these numbers are to be tracked so they are considered "sensitive" variables. This is, therefore, the set of variables with which one would then perform computations, and based on which one can then extract both the value of the function and its derivatives with the member functions below. The values of the components of the returned object are initialized to the values set with register_independent_variable().
Definition at line 1251 of file ad_helpers.cc.
internal::Extractor<dim, ExtractorType>::template tensor_type<ad_type> Differentiation::AD::PointLevelFunctionsBase< dim, ADNumberTypeCode, ScalarType >::get_sensitive_variables | ( | const ExtractorType & | extractor | ) | const |
void Differentiation::AD::PointLevelFunctionsBase< dim, ADNumberTypeCode, ScalarType >::set_independent_variables | ( | const std::vector< scalar_type > & | values | ) |
Set the values for the independent variables \(\mathbf{X}\).
[in] | values | A vector that defines the values of all independent variables. |
scalar_type
. Depending on the selected ADNumberTypeCode
, this may or may not correspond with the ScalarType
prescribed as a template argument.keep_independent_values
flag has been set when HelperBase::start_recording_operations() is called then the tape is immediately usable after creation, and the values of the independent variables set by register_independent_variables() are those at which the function is to be evaluated. In this case, a separate call to this function is not strictly necessary. Definition at line 1301 of file ad_helpers.cc.
void Differentiation::AD::PointLevelFunctionsBase< dim, ADNumberTypeCode, ScalarType >::set_independent_variable | ( | const ValueType & | value, |
const ExtractorType & | extractor | ||
) |
Set the values for a subset of independent variables \(\mathbf{A} \subset \mathbf{X}\).
[in] | value | A field that defines the values of a number of independent variables. |
[in] | extractor | An extractor associated with the input field variables. This effectively defines which components of the global set of independent variables this field is associated with. |
scalar_type
. Depending on the selected ADNumberTypeCode
, this may or may not correspond with the ScalarType
prescribed as a template argument.ValueType
. So, for example, if a value is a rank-1 tensor (i.e. of type Tensor<1,dim,scalar_type>), then the extractor must be an FEValuesExtractors::Vector or FEValuesExtractors::Tensor<1>.keep_independent_values
flag has been set when HelperBase::start_recording_operations() is called then the tape is immediately usable after creation, and the values of the independent variables set by register_independent_variable() are those at which the function is to be evaluated. In this case, a separate call to this function is not strictly necessary.
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protected |
Set the actual value of the independent variable \(X_{i}\).
[in] | index | The index in the vector of independent variables. |
[in] | symmetric_component | Mark whether this index relates to a component of a field that has a symmetric counterpart (e.g. if index represents an off-diagonal entry in a symmetric tensor). |
[in] | value | The value to set the index'd independent variable to. |
Definition at line 1279 of file ad_helpers.cc.
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protected |
Return whether the index'th
independent variables is one for which we must take into account symmetry when extracting their gradient or Hessian values.
Definition at line 1197 of file ad_helpers.cc.
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protected |
Return the number of independent variables that have been marked as being components of a symmetric field.
Definition at line 1211 of file ad_helpers.cc.
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static |
Type definition for the dimension of the associated input and output tensor types.
Definition at line 2648 of file ad_helpers.h.
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private |
The independent variables for which we must take into account symmetry when extracting their gradient or Hessian values.
Definition at line 2920 of file ad_helpers.h.