firedrake.adjoint_utils.blocks package

Submodules

firedrake.adjoint_utils.blocks.assembly module

class firedrake.adjoint_utils.blocks.assembly.AssembleBlock(form, ad_block_tag=None)

Bases: Block

block_helper

compute_action_adjoint(adj_input, arity_form, form=None, c_rep=None, space=None, dform=None)

This computes the action of the adjoint of the derivative of form wrt c_rep on adj_input. In other words, it returns: <(dform/dc_rep)*, adj_input>

• If form has arity 0 => dform/dc_rep is a 1-form and adj_input a float, we can simply use the * operator.

• If form has arity 1 => dform/dc_rep is a 2-form and we can symbolically take its adjoint and then apply the action on adj_input, to finally assemble the result.

evaluate_adj_component(inputs, adj_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for evaluating the adjoint of the block that corresponds to one dependency. If one considers the adjoint action a vector right multiplied with the Jacobian matrix, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• adj_inputs (list) – A list of the adjoint input values, determined by the outputs list.

• block_variable (BlockVariable) – The block variable of the dependency corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_adj method. Default is None.

Returns:

The resulting product.

Return type:

An object of a type consistent with the adj_value type of block_variable

evaluate_hessian_component(inputs, hessian_inputs, adj_inputs, block_variable, idx, relevant_dependencies, prepared=None)

This method must be overridden.

The method should implement a routine for evaluating the hessian of the block. It is preferable that a “Forward-over-Reverse” scheme is used. Thus the hessians are evaluated in reverse (starting with the last block on the tape).

evaluate_tlm_component(inputs, tlm_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for computing the tangent linear model of the block that corresponds to one output. If one considers the tangent linear action as a Jacobian matrix multiplied with a vector, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• tlm_inputs (list) – A list of the tlm input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_tlm method. Default is None.

Returns:

The resulting product.

Return type:

An object of the same type as block_variable.saved_output

prepare_evaluate_adj(inputs, adj_inputs, relevant_dependencies)

Runs preparations before evalute_adj_component is ran.

The return value is supplied to each of the subsequent evaluate_adj_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• adj_inputs – The adjoint inputs

• relevant_dependencies – A list of the relevant block variables for evaluate_adj_component.

Returns:

Anything. The returned value is supplied to evaluate_adj_component

prepare_evaluate_hessian(inputs, hessian_inputs, adj_inputs, relevant_dependencies)

Runs preparations before evalute_hessian_component is ran for each relevant dependency.

The return value is supplied to each of the subsequent evaluate_hessian_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• hessian_inputs – The hessian inputs

• adj_inputs – The adjoint inputs

• relevant_dependencies – A list of the relevant block variables for evaluate_hessian_component.

Returns:

Anything. The returned value is supplied to evaluate_hessian_component

prepare_evaluate_tlm(inputs, tlm_inputs, relevant_outputs)

Runs preparations before evalute_tlm_component is ran.

The return value is supplied to each of the subsequent evaluate_tlm_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• tlm_inputs – The tlm inputs

• relevant_outputs – A list of the relevant block variables for evaluate_tlm_component.

Returns:

Anything. The returned value is supplied to evaluate_tlm_component

prepare_recompute_component(inputs, relevant_outputs)

Runs preparations before recompute_component is ran.

The return value is supplied to each of the subsequent recompute_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• relevant_outputs – A list of the relevant block variables for recompute_component.

Returns:

Anything. The returned value is supplied to recompute_component

recompute_component(inputs, block_variable, idx, prepared)

This method must be overridden.

The method should implement a routine for recomputing one output of the block in the forward computations. The output to recompute is determined by the idx argument, which corresponds to the index of the output in the outputs list. If the block only has a single output, then idx will always be 0.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the output to compute.

• prepared (object) – Anything returned by the prepare_recompute_component method. Default is None.

Returns:

An object of the same type as block_variable.checkpoint which is determined by OverloadedType._ad_create_checkpoint (often the same as block_variable.saved_output): The new output.

firedrake.adjoint_utils.blocks.block_utils module

firedrake.adjoint_utils.blocks.block_utils.isconstant(expr)

Check whether expression is constant type. In firedrake this is a function in the real space Ie: firedrake.Function(FunctionSpace(mesh, “R”))

firedrake.adjoint_utils.blocks.constant module

class firedrake.adjoint_utils.blocks.constant.ConstantAssignBlock(other, ad_block_tag=None)

Bases: Block

block_helper

evaluate_adj_component(inputs, adj_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for evaluating the adjoint of the block that corresponds to one dependency. If one considers the adjoint action a vector right multiplied with the Jacobian matrix, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• adj_inputs (list) – A list of the adjoint input values, determined by the outputs list.

• block_variable (BlockVariable) – The block variable of the dependency corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_adj method. Default is None.

Returns:

The resulting product.

Return type:

An object of a type consistent with the adj_value type of block_variable

evaluate_hessian_component(inputs, hessian_inputs, adj_inputs, block_variable, idx, relevant_dependencies, prepared=None)

This method must be overridden.

The method should implement a routine for evaluating the hessian of the block. It is preferable that a “Forward-over-Reverse” scheme is used. Thus the hessians are evaluated in reverse (starting with the last block on the tape).

evaluate_tlm_component(inputs, tlm_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for computing the tangent linear model of the block that corresponds to one output. If one considers the tangent linear action as a Jacobian matrix multiplied with a vector, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• tlm_inputs (list) – A list of the tlm input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_tlm method. Default is None.

Returns:

The resulting product.

Return type:

An object of the same type as block_variable.saved_output

prepare_evaluate_adj(inputs, adj_inputs, relevant_dependencies)

Runs preparations before evalute_adj_component is ran.

The return value is supplied to each of the subsequent evaluate_adj_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• adj_inputs – The adjoint inputs

• relevant_dependencies – A list of the relevant block variables for evaluate_adj_component.

Returns:

Anything. The returned value is supplied to evaluate_adj_component

prepare_evaluate_hessian(inputs, hessian_inputs, adj_inputs, relevant_dependencies)

Runs preparations before evalute_hessian_component is ran for each relevant dependency.

The return value is supplied to each of the subsequent evaluate_hessian_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• hessian_inputs – The hessian inputs

• adj_inputs – The adjoint inputs

• relevant_dependencies – A list of the relevant block variables for evaluate_hessian_component.

Returns:

Anything. The returned value is supplied to evaluate_hessian_component

recompute_component(inputs, block_variable, idx, prepared)

This method must be overridden.

The method should implement a routine for recomputing one output of the block in the forward computations. The output to recompute is determined by the idx argument, which corresponds to the index of the output in the outputs list. If the block only has a single output, then idx will always be 0.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the output to compute.

• prepared (object) – Anything returned by the prepare_recompute_component method. Default is None.

Returns:

An object of the same type as block_variable.checkpoint which is determined by OverloadedType._ad_create_checkpoint (often the same as block_variable.saved_output): The new output.

firedrake.adjoint_utils.blocks.constant.constant_from_values(constant, values=None)

Returns a new Constant with constant.values().

If the optional argument values is provided, then values will be the values of the new Constant instead, while still preserving the ufl_shape of constant.

Parameters:

• constant – A constant with the ufl_shape to preserve. values

• (numpy.array) – An optional argument to use instead of

• constant.values().

Returns:

The created Constant of the same type as constant.

Return type:

Constant

firedrake.adjoint_utils.blocks.dirichlet_bc module

class firedrake.adjoint_utils.blocks.dirichlet_bc.DirichletBCBlock(*args, **kwargs)

Bases: Block

block_helper

evaluate_adj_component(inputs, adj_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for evaluating the adjoint of the block that corresponds to one dependency. If one considers the adjoint action a vector right multiplied with the Jacobian matrix, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• adj_inputs (list) – A list of the adjoint input values, determined by the outputs list.

• block_variable (BlockVariable) – The block variable of the dependency corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_adj method. Default is None.

Returns:

The resulting product.

Return type:

An object of a type consistent with the adj_value type of block_variable

evaluate_hessian_component(inputs, hessian_inputs, adj_inputs, block_variable, idx, relevant_dependencies, prepared=None)

This method must be overridden.

The method should implement a routine for evaluating the hessian of the block. It is preferable that a “Forward-over-Reverse” scheme is used. Thus the hessians are evaluated in reverse (starting with the last block on the tape).

evaluate_tlm_component(inputs, tlm_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for computing the tangent linear model of the block that corresponds to one output. If one considers the tangent linear action as a Jacobian matrix multiplied with a vector, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• tlm_inputs (list) – A list of the tlm input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_tlm method. Default is None.

Returns:

The resulting product.

Return type:

An object of the same type as block_variable.saved_output

recompute()

Recomputes the overloaded function with new inputs

and stores the results in the checkpoint attribute of the outputs.

This method will by default call the recompute_component method for each output.

Parameters:

markings (bool) – If True, then each block_variable will have set marked_in_path attribute indicating whether their checkpoints need to be recomputed for recomputing the final target function value. Default is False.

firedrake.adjoint_utils.blocks.dirichlet_bc.extract_bc_subvector(value, Vtarget, bc)

Extract from value (a function in a mixed space), the sub function corresponding to the part of the space bc applies to. Vtarget is the target (collapsed) space.

firedrake.adjoint_utils.blocks.function module

class firedrake.adjoint_utils.blocks.function.FunctionAssignBlock(func, other, ad_block_tag=None)

Bases: Block

block_helper

evaluate_adj_component(inputs, adj_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for evaluating the adjoint of the block that corresponds to one dependency. If one considers the adjoint action a vector right multiplied with the Jacobian matrix, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• adj_inputs (list) – A list of the adjoint input values, determined by the outputs list.

• block_variable (BlockVariable) – The block variable of the dependency corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_adj method. Default is None.

Returns:

The resulting product.

Return type:

An object of a type consistent with the adj_value type of block_variable

evaluate_hessian_component(inputs, hessian_inputs, adj_inputs, block_variable, idx, relevant_dependencies, prepared=None)

This method must be overridden.

The method should implement a routine for evaluating the hessian of the block. It is preferable that a “Forward-over-Reverse” scheme is used. Thus the hessians are evaluated in reverse (starting with the last block on the tape).

evaluate_tlm_component(inputs, tlm_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for computing the tangent linear model of the block that corresponds to one output. If one considers the tangent linear action as a Jacobian matrix multiplied with a vector, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• tlm_inputs (list) – A list of the tlm input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_tlm method. Default is None.

Returns:

The resulting product.

Return type:

An object of the same type as block_variable.saved_output

prepare_evaluate_adj(inputs, adj_inputs, relevant_dependencies)

Runs preparations before evalute_adj_component is ran.

The return value is supplied to each of the subsequent evaluate_adj_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• adj_inputs – The adjoint inputs

• relevant_dependencies – A list of the relevant block variables for evaluate_adj_component.

Returns:

Anything. The returned value is supplied to evaluate_adj_component

prepare_evaluate_hessian(inputs, hessian_inputs, adj_inputs, relevant_dependencies)

Runs preparations before evalute_hessian_component is ran for each relevant dependency.

The return value is supplied to each of the subsequent evaluate_hessian_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• hessian_inputs – The hessian inputs

• adj_inputs – The adjoint inputs

• relevant_dependencies – A list of the relevant block variables for evaluate_hessian_component.

Returns:

Anything. The returned value is supplied to evaluate_hessian_component

prepare_evaluate_tlm(inputs, tlm_inputs, relevant_outputs)

Runs preparations before evalute_tlm_component is ran.

The return value is supplied to each of the subsequent evaluate_tlm_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• tlm_inputs – The tlm inputs

• relevant_outputs – A list of the relevant block variables for evaluate_tlm_component.

Returns:

Anything. The returned value is supplied to evaluate_tlm_component

prepare_recompute_component(inputs, relevant_outputs)

Runs preparations before recompute_component is ran.

The return value is supplied to each of the subsequent recompute_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• relevant_outputs – A list of the relevant block variables for recompute_component.

Returns:

Anything. The returned value is supplied to recompute_component

recompute_component(inputs, block_variable, idx, prepared=None)

Recompute the assignment.

Parameters:

• inputs (list of Function or Constant) – The variables in the RHS of the assignment.

• block_variable (pyadjoint.block_variable.BlockVariable) – The output block variable.

• idx (int) – Index associated to the inputs list.

• prepared – The precomputed RHS value.

Notes

Recomputes the block_variable only if the checkpoint was not delegated to another Function.

Returns:

Return either the firedrake function or BlockVariable checkpoint to which was delegated the checkpointing.

Return type:

Function

class firedrake.adjoint_utils.blocks.function.FunctionMergeBlock(func, idx, ad_block_tag=None)

Bases: Block

block_helper

evaluate_adj_component(inputs, adj_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for evaluating the adjoint of the block that corresponds to one dependency. If one considers the adjoint action a vector right multiplied with the Jacobian matrix, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• adj_inputs (list) – A list of the adjoint input values, determined by the outputs list.

• block_variable (BlockVariable) – The block variable of the dependency corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_adj method. Default is None.

Returns:

The resulting product.

Return type:

An object of a type consistent with the adj_value type of block_variable

evaluate_hessian_component(inputs, hessian_inputs, adj_inputs, block_variable, idx, relevant_dependencies, prepared=None)

This method must be overridden.

The method should implement a routine for evaluating the hessian of the block. It is preferable that a “Forward-over-Reverse” scheme is used. Thus the hessians are evaluated in reverse (starting with the last block on the tape).

evaluate_tlm()

Computes the tangent linear action and stores the result in the tlm_value attribute of the outputs.

This method will by default call the evaluate_tlm_component method for each output.

Parameters:

markings (bool) – If True, then each block_variable will have set marked_in_path attribute indicating whether their tlm components are relevant for computing the final target tlm values. Default is False.

recompute_component(inputs, block_variable, idx, prepared)

This method must be overridden.

The method should implement a routine for recomputing one output of the block in the forward computations. The output to recompute is determined by the idx argument, which corresponds to the index of the output in the outputs list. If the block only has a single output, then idx will always be 0.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the output to compute.

• prepared (object) – Anything returned by the prepare_recompute_component method. Default is None.

Returns:

An object of the same type as block_variable.checkpoint which is determined by OverloadedType._ad_create_checkpoint (often the same as block_variable.saved_output): The new output.

class firedrake.adjoint_utils.blocks.function.SubfunctionBlock(func, idx, ad_block_tag=None)

Bases: Block

block_helper

evaluate_adj_component(inputs, adj_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for evaluating the adjoint of the block that corresponds to one dependency. If one considers the adjoint action a vector right multiplied with the Jacobian matrix, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• adj_inputs (list) – A list of the adjoint input values, determined by the outputs list.

• block_variable (BlockVariable) – The block variable of the dependency corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_adj method. Default is None.

Returns:

The resulting product.

Return type:

An object of a type consistent with the adj_value type of block_variable

evaluate_hessian_component(inputs, hessian_inputs, adj_inputs, block_variable, idx, relevant_dependencies, prepared=None)

This method must be overridden.

The method should implement a routine for evaluating the hessian of the block. It is preferable that a “Forward-over-Reverse” scheme is used. Thus the hessians are evaluated in reverse (starting with the last block on the tape).

evaluate_tlm_component(inputs, tlm_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for computing the tangent linear model of the block that corresponds to one output. If one considers the tangent linear action as a Jacobian matrix multiplied with a vector, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• tlm_inputs (list) – A list of the tlm input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_tlm method. Default is None.

Returns:

The resulting product.

Return type:

An object of the same type as block_variable.saved_output

recompute_component(inputs, block_variable, idx, prepared)

This method must be overridden.

The method should implement a routine for recomputing one output of the block in the forward computations. The output to recompute is determined by the idx argument, which corresponds to the index of the output in the outputs list. If the block only has a single output, then idx will always be 0.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the output to compute.

• prepared (object) – Anything returned by the prepare_recompute_component method. Default is None.

Returns:

An object of the same type as block_variable.checkpoint which is determined by OverloadedType._ad_create_checkpoint (often the same as block_variable.saved_output): The new output.

firedrake.adjoint_utils.blocks.mesh module

class firedrake.adjoint_utils.blocks.mesh.MeshInputBlock(mesh, ad_block_tag=None)

Bases: Block

Block which links a MeshGeometry to its coordinates, which is a firedrake function.

block_helper

evaluate_adj_component(inputs, adj_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for evaluating the adjoint of the block that corresponds to one dependency. If one considers the adjoint action a vector right multiplied with the Jacobian matrix, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• adj_inputs (list) – A list of the adjoint input values, determined by the outputs list.

• block_variable (BlockVariable) – The block variable of the dependency corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_adj method. Default is None.

Returns:

The resulting product.

Return type:

An object of a type consistent with the adj_value type of block_variable

evaluate_hessian_component(inputs, hessian_inputs, adj_inputs, idx, block_variable, relevant_dependencies, prepared=None)

This method must be overridden.

The method should implement a routine for evaluating the hessian of the block. It is preferable that a “Forward-over-Reverse” scheme is used. Thus the hessians are evaluated in reverse (starting with the last block on the tape).

evaluate_tlm_component(inputs, tlm_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for computing the tangent linear model of the block that corresponds to one output. If one considers the tangent linear action as a Jacobian matrix multiplied with a vector, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• tlm_inputs (list) – A list of the tlm input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_tlm method. Default is None.

Returns:

The resulting product.

Return type:

An object of the same type as block_variable.saved_output

recompute_component(inputs, block_variable, idx, prepared)

This method must be overridden.

The method should implement a routine for recomputing one output of the block in the forward computations. The output to recompute is determined by the idx argument, which corresponds to the index of the output in the outputs list. If the block only has a single output, then idx will always be 0.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the output to compute.

• prepared (object) – Anything returned by the prepare_recompute_component method. Default is None.

Returns:

An object of the same type as block_variable.checkpoint which is determined by OverloadedType._ad_create_checkpoint (often the same as block_variable.saved_output): The new output.

class firedrake.adjoint_utils.blocks.mesh.MeshOutputBlock(func, mesh, ad_block_tag=None)

Bases: Block

Block which is called when the coordinates of a mesh are changed.

block_helper

evaluate_adj_component(inputs, adj_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for evaluating the adjoint of the block that corresponds to one dependency. If one considers the adjoint action a vector right multiplied with the Jacobian matrix, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• adj_inputs (list) – A list of the adjoint input values, determined by the outputs list.

• block_variable (BlockVariable) – The block variable of the dependency corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_adj method. Default is None.

Returns:

The resulting product.

Return type:

An object of a type consistent with the adj_value type of block_variable

evaluate_hessian_component(inputs, hessian_inputs, adj_inputs, idx, block_variable, relevant_dependencies, prepared=None)

This method must be overridden.

The method should implement a routine for evaluating the hessian of the block. It is preferable that a “Forward-over-Reverse” scheme is used. Thus the hessians are evaluated in reverse (starting with the last block on the tape).

evaluate_tlm_component(inputs, tlm_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for computing the tangent linear model of the block that corresponds to one output. If one considers the tangent linear action as a Jacobian matrix multiplied with a vector, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• tlm_inputs (list) – A list of the tlm input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_tlm method. Default is None.

Returns:

The resulting product.

Return type:

An object of the same type as block_variable.saved_output

recompute_component(inputs, block_variable, idx, prepared)

This method must be overridden.

The method should implement a routine for recomputing one output of the block in the forward computations. The output to recompute is determined by the idx argument, which corresponds to the index of the output in the outputs list. If the block only has a single output, then idx will always be 0.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the output to compute.

• prepared (object) – Anything returned by the prepare_recompute_component method. Default is None.

Returns:

An object of the same type as block_variable.checkpoint which is determined by OverloadedType._ad_create_checkpoint (often the same as block_variable.saved_output): The new output.

firedrake.adjoint_utils.blocks.solving module

class firedrake.adjoint_utils.blocks.solving.GenericSolveBlock(lhs, rhs, func, bcs, *args, **kwargs)

Bases: Block

block_helper

evaluate_adj_component(inputs, adj_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for evaluating the adjoint of the block that corresponds to one dependency. If one considers the adjoint action a vector right multiplied with the Jacobian matrix, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• adj_inputs (list) – A list of the adjoint input values, determined by the outputs list.

• block_variable (BlockVariable) – The block variable of the dependency corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_adj method. Default is None.

Returns:

The resulting product.

Return type:

An object of a type consistent with the adj_value type of block_variable

evaluate_hessian_component(inputs, hessian_inputs, adj_inputs, block_variable, idx, relevant_dependencies, prepared=None)

This method must be overridden.

The method should implement a routine for evaluating the hessian of the block. It is preferable that a “Forward-over-Reverse” scheme is used. Thus the hessians are evaluated in reverse (starting with the last block on the tape).

evaluate_tlm_component(inputs, tlm_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for computing the tangent linear model of the block that corresponds to one output. If one considers the tangent linear action as a Jacobian matrix multiplied with a vector, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• tlm_inputs (list) – A list of the tlm input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_tlm method. Default is None.

Returns:

The resulting product.

Return type:

An object of the same type as block_variable.saved_output

pop_kwargs_keys = ['adj_cb', 'adj_bdy_cb', 'adj2_cb', 'adj2_bdy_cb', 'forward_args', 'forward_kwargs', 'adj_args', 'adj_kwargs']

prepare_evaluate_adj(inputs, adj_inputs, relevant_dependencies)

Runs preparations before evalute_adj_component is ran.

The return value is supplied to each of the subsequent evaluate_adj_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• adj_inputs – The adjoint inputs

• relevant_dependencies – A list of the relevant block variables for evaluate_adj_component.

Returns:

Anything. The returned value is supplied to evaluate_adj_component

prepare_evaluate_hessian(inputs, hessian_inputs, adj_inputs, relevant_dependencies)

Runs preparations before evalute_hessian_component is ran for each relevant dependency.

The return value is supplied to each of the subsequent evaluate_hessian_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• hessian_inputs – The hessian inputs

• adj_inputs – The adjoint inputs

• relevant_dependencies – A list of the relevant block variables for evaluate_hessian_component.

Returns:

Anything. The returned value is supplied to evaluate_hessian_component

prepare_evaluate_tlm(inputs, tlm_inputs, relevant_outputs)

Runs preparations before evalute_tlm_component is ran.

The return value is supplied to each of the subsequent evaluate_tlm_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• tlm_inputs – The tlm inputs

• relevant_outputs – A list of the relevant block variables for evaluate_tlm_component.

Returns:

Anything. The returned value is supplied to evaluate_tlm_component

prepare_recompute_component(inputs, relevant_outputs)

Runs preparations before recompute_component is ran.

The return value is supplied to each of the subsequent recompute_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• relevant_outputs – A list of the relevant block variables for recompute_component.

Returns:

Anything. The returned value is supplied to recompute_component

recompute_component(inputs, block_variable, idx, prepared)

This method must be overridden.

The method should implement a routine for recomputing one output of the block in the forward computations. The output to recompute is determined by the idx argument, which corresponds to the index of the output in the outputs list. If the block only has a single output, then idx will always be 0.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the output to compute.

• prepared (object) – Anything returned by the prepare_recompute_component method. Default is None.

Returns:

An object of the same type as block_variable.checkpoint which is determined by OverloadedType._ad_create_checkpoint (often the same as block_variable.saved_output): The new output.

class firedrake.adjoint_utils.blocks.solving.NonlinearVariationalSolveBlock(equation, func, bcs, adj_F, dFdm_cache, problem_J, solver_params, solver_kwargs, **kwargs)

Bases: GenericSolveBlock

block_helper

evaluate_adj_component(inputs, adj_inputs, block_variable, idx, prepared=None)

This method should be overridden.

The method should implement a routine for evaluating the adjoint of the block that corresponds to one dependency. If one considers the adjoint action a vector right multiplied with the Jacobian matrix, then this method should return one entry in the resulting product, where the entry returned is decided by the argument idx.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• adj_inputs (list) – A list of the adjoint input values, determined by the outputs list.

• block_variable (BlockVariable) – The block variable of the dependency corresponding to index idx.

• idx (int) – The index of the component to compute.

• prepared (object) – Anything returned by the prepare_evaluate_adj method. Default is None.

Returns:

The resulting product.

Return type:

An object of a type consistent with the adj_value type of block_variable

prepare_evaluate_adj(inputs, adj_inputs, relevant_dependencies)

Runs preparations before evalute_adj_component is ran.

The return value is supplied to each of the subsequent evaluate_adj_component calls. This method is intended to be overridden for blocks that require such preparations, by default there is none.

Parameters:

• inputs – The values of the inputs

• adj_inputs – The adjoint inputs

• relevant_dependencies – A list of the relevant block variables for evaluate_adj_component.

Returns:

Anything. The returned value is supplied to evaluate_adj_component

class firedrake.adjoint_utils.blocks.solving.ProjectBlock(v, V, output, bcs=[], *args, **kwargs)

Bases: SolveVarFormBlock

block_helper

class firedrake.adjoint_utils.blocks.solving.SolveLinearSystemBlock(A, u, b, *args, **kwargs)

Bases: GenericSolveBlock

block_helper

class firedrake.adjoint_utils.blocks.solving.SolveVarFormBlock(equation, func, bcs=[], *args, **kwargs)

Bases: GenericSolveBlock

block_helper

class firedrake.adjoint_utils.blocks.solving.SupermeshProjectBlock(source, target_space, target, bcs=[], **kwargs)

Bases: Block

Annotates supermesh projection.

Suppose we have a source space, \(V_A\), and a target space, \(V_B\). Projecting a source from \(V_A\) to \(V_B\) amounts to solving the linear system

\[M_B * v_B = M_{AB} * v_A,\]

where

• \(M_B\) is the mass matrix on \(V_B\),

• \(M_{AB}\) is the mixed mass matrix for \(V_A\) and \(V_B\),

• \(v_A\) and \(v_B\) are vector representations of the source and target Function s.

This can be broken into two steps:

Step 1. form RHS, multiplying the source with the mixed mass matrix;

Step 2. solve linear system.

apply_mixedmass(a)

block_helper

evaluate_adj_component(inputs, adj_inputs, block_variable, idx, prepared=None)

Evaluate the adjoint to one output of the block

Recall that the forward propagation can be broken down as:

Step 1. multiply \(w := M_{AB} * v_A\);

Step 2. solve \(M_B * v_B = w\).

For a seed vector \(v_B^{seed}\) from the target space, the adjoint is given by:

Adjoint of step 2. solve \(M_B^T * w = v_B^{seed}\) for w;

Adjoint of step 1. multiply \(v_A^{adj} := M_{AB}^T * w\).

evaluate_hessian_component(inputs, hessian_inputs, adj_inputs, block_variable, idx, relevant_dependencies, prepared=None)

This method must be overridden.

The method should implement a routine for evaluating the hessian of the block. It is preferable that a “Forward-over-Reverse” scheme is used. Thus the hessians are evaluated in reverse (starting with the last block on the tape).

evaluate_tlm_component(inputs, tlm_inputs, block_variable, idx, prepared=None)

Given that the input is a Function, we just have a linear operation. As such, the tlm is just the sum of each tlm input projected into the target space.

recompute_component(inputs, block_variable, idx, prepared)

This method must be overridden.

The method should implement a routine for recomputing one output of the block in the forward computations. The output to recompute is determined by the idx argument, which corresponds to the index of the output in the outputs list. If the block only has a single output, then idx will always be 0.

Parameters:

• inputs (list) – A list of the saved input values, determined by the dependencies list.

• block_variable (BlockVariable) – The block variable of the output corresponding to index idx.

• idx (int) – The index of the output to compute.

• prepared (object) – Anything returned by the prepare_recompute_component method. Default is None.

Returns:

An object of the same type as block_variable.checkpoint which is determined by OverloadedType._ad_create_checkpoint (often the same as block_variable.saved_output): The new output.

firedrake.adjoint_utils.blocks.solving.extract_subfunction(u, V)

If V is a subspace of the function-space of u, return the component of u that is in that subspace.

firedrake.adjoint_utils.blocks.solving.solve_init_params(self, args, kwargs, varform)

Module contents