Drake
AffineSystem< T > Class Template Reference

A discrete OR continuous affine system (with constant coefficients). More...

#include <drake/systems/primitives/affine_system.h>

## Public Member Functions

AffineSystem (const Eigen::Ref< const Eigen::MatrixXd > &A, const Eigen::Ref< const Eigen::MatrixXd > &B, const Eigen::Ref< const Eigen::VectorXd > &f0, const Eigen::Ref< const Eigen::MatrixXd > &C, const Eigen::Ref< const Eigen::MatrixXd > &D, const Eigen::Ref< const Eigen::VectorXd > &y0, double time_period=0.0)
Constructs an Affine system with a fixed set of coefficient matrices A, B,C, and D as well as fixed initial velocity offset xDot0 and output offset y0. More...

template<typename U >
AffineSystem (const AffineSystem< U > &)
Scalar-converting copy constructor. See System Scalar Conversion. More...

Does not allow copy, move, or assignment
AffineSystem (const AffineSystem &)=delete

AffineSystemoperator= (const AffineSystem &)=delete

AffineSystem (AffineSystem &&)=delete

AffineSystemoperator= (AffineSystem &&)=delete

Helper getter methods.
const Eigen::MatrixXd & A () const

const Eigen::MatrixXd & B () const

const Eigen::VectorXd & f0 () const

const Eigen::MatrixXd & C () const

const Eigen::MatrixXd & D () const

const Eigen::VectorXd & y0 () const

Implementations of TimeVaryingAffineSystem<T>'s pure virtual

methods.

MatrixX< TA (const T &) const final

MatrixX< TB (const T &) const final

VectorX< Tf0 (const T &) const final

MatrixX< TC (const T &) const final

MatrixX< TD (const T &) const final

VectorX< Ty0 (const T &) const final

Public Member Functions inherited from TimeVaryingAffineSystem< T >
const InputPort< T > & get_input_port () const
Returns the input port containing the externally applied input. More...

const OutputPort< T > & get_output_port () const
Returns the output port containing the output state. More...

double time_period () const

int num_states () const

int num_inputs () const

int num_outputs () const

TimeVaryingAffineSystem (const TimeVaryingAffineSystem &)=delete

TimeVaryingAffineSystemoperator= (const TimeVaryingAffineSystem &)=delete

TimeVaryingAffineSystem (TimeVaryingAffineSystem &&)=delete

TimeVaryingAffineSystemoperator= (TimeVaryingAffineSystem &&)=delete

Public Member Functions inherited from LeafSystem< T >
~LeafSystem () override

std::unique_ptr< CompositeEventCollection< T > > AllocateCompositeEventCollection () const final
Allocates a CompositeEventCollection object for this system. More...

std::unique_ptr< LeafContext< T > > AllocateContext () const
Shadows System<T>::AllocateContext to provide a more concrete return type LeafContext<T>. More...

std::unique_ptr< ContextBaseDoAllocateContext () const final
Derived class implementations should allocate a suitable concrete Context type, then invoke the above InitializeContextBase() method. More...

void SetDefaultState (const Context< T > &context, State< T > *state) const override
Default implementation: sets all continuous state to the model vector given in DeclareContinuousState (or zero if no model vector was given) and discrete states to zero. More...

void SetDefaultParameters (const Context< T > &context, Parameters< T > *parameters) const override
Default implementation: sets all numeric parameters to the model vector given to DeclareNumericParameter, or else if no model was provided sets the numeric parameter to one. More...

std::unique_ptr< ContinuousState< T > > AllocateTimeDerivatives () const override
Returns the AllocateContinuousState value, which must not be nullptr. More...

std::unique_ptr< DiscreteValues< T > > AllocateDiscreteVariables () const override
Returns the AllocateDiscreteState value, which must not be nullptr. More...

std::multimap< int, intGetDirectFeedthroughs () const final
Reports all direct feedthroughs from input ports to output ports. More...

int get_num_continuous_states () const final
Returns the dimension of the continuous state vector that has been declared until now. More...

LeafSystem (const LeafSystem &)=delete

LeafSystemoperator= (const LeafSystem &)=delete

LeafSystem (LeafSystem &&)=delete

LeafSystemoperator= (LeafSystem &&)=delete

Public Member Functions inherited from System< T >
~System () override=default

void GetWitnessFunctions (const Context< T > &context, std::vector< const WitnessFunction< T > *> *w) const
Gets the witness functions active for the given state. More...

T CalcWitnessValue (const Context< T > &context, const WitnessFunction< T > &witness_func) const
Evaluates a witness function at the given context. More...

System (const System &)=delete

Systemoperator= (const System &)=delete

System (System &&)=delete

Systemoperator= (System &&)=delete

std::unique_ptr< Context< T > > AllocateContext () const
Returns a Context<T> suitable for use with this System<T>. More...

std::unique_ptr< BasicVector< T > > AllocateInputVector (const InputPort< T > &input_port) const
Given an input port, allocates the vector storage. More...

std::unique_ptr< AbstractValueAllocateInputAbstract (const InputPort< T > &input_port) const
Given an input port, allocates the abstract storage. More...

std::unique_ptr< SystemOutput< T > > AllocateOutput () const
Returns a container that can hold the values of all of this System's output ports. More...

std::unique_ptr< Context< T > > CreateDefaultContext () const
This convenience method allocates a context using AllocateContext() and sets its default values using SetDefaultContext(). More...

void SetDefaultContext (Context< T > *context) const

virtual void SetRandomState (const Context< T > &context, State< T > *state, RandomGenerator *generator) const
Assigns random values to all elements of the state. More...

virtual void SetRandomParameters (const Context< T > &context, Parameters< T > *parameters, RandomGenerator *generator) const
Assigns random values to all parameters. More...

void SetRandomContext (Context< T > *context, RandomGenerator *generator) const

void AllocateFixedInputs (Context< T > *context) const
For each input port, allocates a fixed input of the concrete type that this System requires, and binds it to the port, disconnecting any prior input. More...

bool HasAnyDirectFeedthrough () const
Returns true if any of the inputs to the system might be directly fed through to any of its outputs and false otherwise. More...

bool HasDirectFeedthrough (int output_port) const
Returns true if there might be direct-feedthrough from any input port to the given output_port, and false otherwise. More...

bool HasDirectFeedthrough (int input_port, int output_port) const
Returns true if there might be direct-feedthrough from the given input_port to the given output_port, and false otherwise. More...

void Publish (const Context< T > &context, const EventCollection< PublishEvent< T >> &events) const
This method is the public entry point for dispatching all publish event handlers. More...

void Publish (const Context< T > &context) const
Forces a publish on the system, given a context. More...

const ContinuousState< T > & EvalTimeDerivatives (const Context< T > &context) const
Returns a reference to the cached value of the continuous state variable time derivatives, evaluating first if necessary using CalcTimeDerivatives(). More...

const TEvalPotentialEnergy (const Context< T > &context) const
Returns a reference to the cached value of the potential energy (PE), evaluating first if necessary using CalcPotentialEnergy(). More...

const TEvalKineticEnergy (const Context< T > &context) const
Returns a reference to the cached value of the kinetic energy (KE), evaluating first if necessary using CalcKineticEnergy(). More...

const TEvalConservativePower (const Context< T > &context) const
Returns a reference to the cached value of the conservative power (Pc), evaluating first if necessary using CalcConservativePower(). More...

const TEvalNonConservativePower (const Context< T > &context) const
Returns a reference to the cached value of the non-conservative power (Pnc), evaluating first if necessary using CalcNonConservativePower(). More...

template<template< typename > class Vec = BasicVector>
const Vec< T > * EvalVectorInput (const Context< T > &context, int port_index) const
Returns the value of the vector-valued input port with the given port_index as a BasicVector or a specific subclass Vec derived from BasicVector. More...

Eigen::VectorBlock< const VectorX< T > > EvalEigenVectorInput (const Context< T > &context, int port_index) const
Returns the value of the vector-valued input port with the given port_index as an Eigen vector. More...

int get_num_constraint_equations (const Context< T > &context) const
Gets the number of constraint equations for this system using the given context (useful in case the number of constraints is dependent upon the current state (as might be the case with a system modeled using piecewise differential algebraic equations). More...

Eigen::VectorXd EvalConstraintEquations (const Context< T > &context) const
Evaluates the constraint equations for the system at the generalized coordinates and generalized velocity specified by the context. More...

Eigen::VectorXd EvalConstraintEquationsDot (const Context< T > &context) const
Computes the time derivative of each constraint equation, evaluated at the generalized coordinates and generalized velocity specified by the context. More...

Eigen::VectorXd CalcVelocityChangeFromConstraintImpulses (const Context< T > &context, const Eigen::MatrixXd &J, const Eigen::VectorXd &lambda) const
Computes the change in velocity from applying the given constraint forces to the system at the given context. More...

double CalcConstraintErrorNorm (const Context< T > &context, const Eigen::VectorXd &error) const
Computes the norm on constraint error (used as a metric for comparing errors between the outputs of algebraic equations applied to two different state variable instances). More...

void CalcTimeDerivatives (const Context< T > &context, ContinuousState< T > *derivatives) const
Calculates the time derivatives xcdot of the continuous state xc into a given output argument. More...

void CalcDiscreteVariableUpdates (const Context< T > &context, const EventCollection< DiscreteUpdateEvent< T >> &events, DiscreteValues< T > *discrete_state) const
This method is the public entry point for dispatching all discrete variable update event handlers. More...

void CalcDiscreteVariableUpdates (const Context< T > &context, DiscreteValues< T > *discrete_state) const
This method forces a discrete update on the system given a context, and the updated discrete state is stored in discrete_state. More...

void CalcUnrestrictedUpdate (const Context< T > &context, const EventCollection< UnrestrictedUpdateEvent< T >> &events, State< T > *state) const
This method is the public entry point for dispatching all unrestricted update event handlers. More...

void CalcUnrestrictedUpdate (const Context< T > &context, State< T > *state) const
This method forces an unrestricted update on the system given a context, and the updated state is stored in state. More...

T CalcNextUpdateTime (const Context< T > &context, CompositeEventCollection< T > *events) const
This method is called by a Simulator during its calculation of the size of the next continuous step to attempt. More...

void GetPerStepEvents (const Context< T > &context, CompositeEventCollection< T > *events) const
This method is called by Simulator::Initialize() to gather all update and publish events that are to be handled in StepTo() at the point before Simulator integrates continuous state. More...

void GetInitializationEvents (const Context< T > &context, CompositeEventCollection< T > *events) const
This method is called by Simulator::Initialize() to gather all update and publish events that need to be handled at initialization before the simulator starts integration. More...

optional< PeriodicEventDataGetUniquePeriodicDiscreteUpdateAttribute () const
Gets whether there exists a unique periodic attribute that triggers one or more discrete update events (and, if so, returns that unique periodic attribute). More...

std::map< PeriodicEventData, std::vector< const Event< T > * >, PeriodicEventDataComparatorGetPeriodicEvents () const
Gets all periodic triggered events for a system. More...

void CalcOutput (const Context< T > &context, SystemOutput< T > *outputs) const
Utility method that computes for every output port i the value y(i) that should result from the current contents of the given Context. More...

T CalcPotentialEnergy (const Context< T > &context) const
Calculates and returns the potential energy represented by the current configuration provided in context. More...

T CalcKineticEnergy (const Context< T > &context) const
Calculates and returns the kinetic energy represented by the current configuration and velocity provided in context. More...

T CalcConservativePower (const Context< T > &context) const
Calculates and returns the conservative power represented by the current contents of the given context. More...

T CalcNonConservativePower (const Context< T > &context) const
Calculates and returns the non-conservative power represented by the current contents of the given context. More...

void MapVelocityToQDot (const Context< T > &context, const VectorBase< T > &generalized_velocity, VectorBase< T > *qdot) const
Transforms a given generalized velocity v to the time derivative qdot of the generalized configuration q taken from the supplied Context. More...

void MapVelocityToQDot (const Context< T > &context, const Eigen::Ref< const VectorX< T >> &generalized_velocity, VectorBase< T > *qdot) const
Transforms the given generalized velocity to the time derivative of generalized configuration. More...

void MapQDotToVelocity (const Context< T > &context, const VectorBase< T > &qdot, VectorBase< T > *generalized_velocity) const
Transforms the time derivative qdot of the generalized configuration q to generalized velocities v. More...

void MapQDotToVelocity (const Context< T > &context, const Eigen::Ref< const VectorX< T >> &qdot, VectorBase< T > *generalized_velocity) const
Transforms the given time derivative qdot of generalized configuration q to generalized velocity v. More...

std::string GetMemoryObjectName () const
Returns a name for this System based on a stringification of its type name and memory address. More...

const InputPort< T > & get_input_port (int port_index) const
Returns the typed input port at index port_index. More...

const InputPort< T > & GetInputPort (const std::string &port_name) const
Returns the typed input port with the unique name port_name. More...

const OutputPort< T > & get_output_port (int port_index) const
Returns the typed output port at index port_index. More...

const OutputPort< T > & GetOutputPort (const std::string &port_name) const
Returns the typed output port with the unique name port_name. More...

int get_num_constraints () const
Returns the number of constraints specified for the system. More...

const SystemConstraint< T > & get_constraint (SystemConstraintIndex constraint_index) const
Returns the constraint at index constraint_index. More...

boolean< TCheckSystemConstraintsSatisfied (const Context< T > &context, double tol) const
Returns true if context satisfies all of the registered SystemConstraints with tolerance tol. More...

void CheckValidOutput (const SystemOutput< T > *output) const
Checks that output is consistent with the number and size of output ports declared by the system. More...

template<typename T1 = T>
void CheckValidContextT (const Context< T1 > &context) const
Checks that context is consistent for this System template. More...

VectorX< TCopyContinuousStateVector (const Context< T > &context) const
Returns a copy of the continuous state vector xc into an Eigen vector. More...

std::string GetGraphvizString (int max_depth=std::numeric_limits< int >::max()) const
Returns a Graphviz string describing this System. More...

int64_t GetGraphvizId () const
Returns an opaque integer that uniquely identifies this system in the Graphviz output. More...

void FixInputPortsFrom (const System< double > &other_system, const Context< double > &other_context, Context< T > *target_context) const
Fixes all of the input ports in target_context to their current values in other_context, as evaluated by other_system. More...

const SystemScalarConverterget_system_scalar_converter () const
(Advanced) Returns the SystemScalarConverter for this object. More...

std::unique_ptr< System< AutoDiffXd > > ToAutoDiffXd () const
Creates a deep copy of this System, transmogrified to use the autodiff scalar type, with a dynamic-sized vector of partial derivatives. More...

std::unique_ptr< System< AutoDiffXd > > ToAutoDiffXdMaybe () const
Creates a deep copy of this system exactly like ToAutoDiffXd(), but returns nullptr if this System does not support autodiff, instead of throwing an exception. More...

std::unique_ptr< System< symbolic::Expression > > ToSymbolic () const
Creates a deep copy of this System, transmogrified to use the symbolic scalar type. More...

std::unique_ptr< System< symbolic::Expression > > ToSymbolicMaybe () const
Creates a deep copy of this system exactly like ToSymbolic(), but returns nullptr if this System does not support symbolic, instead of throwing an exception. More...

Public Member Functions inherited from SystemBase
~SystemBase () override

void set_name (const std::string &name)
Sets the name of the system. More...

const std::string & get_name () const
Returns the name last supplied to set_name(), if any. More...

const std::string & GetSystemName () const final
Returns a human-readable name for this system, for use in messages and logging. More...

std::string GetSystemPathname () const final
Generates and returns a human-readable full path name of this subsystem, for use in messages and logging. More...

std::string GetSystemType () const final
Returns the most-derived type of this concrete System object as a human-readable string suitable for use in error messages. More...

void ThrowIfContextNotCompatible (const ContextBase &context) const final
Throws an exception with an appropriate message if the given context is not compatible with this System. More...

std::unique_ptr< ContextBaseAllocateContext () const
Returns a Context suitable for use with this System. More...

int get_num_input_ports () const
Returns the number of input ports currently allocated in this System. More...

int get_num_output_ports () const
Returns the number of output ports currently allocated in this System. More...

const InputPortBaseget_input_port_base (InputPortIndex port_index) const
Returns a reference to an InputPort given its port_index. More...

const OutputPortBaseget_output_port_base (OutputPortIndex port_index) const
Returns a reference to an OutputPort given its port_index. More...

int get_num_total_inputs () const
Returns the total dimension of all of the vector-valued input ports (as if they were muxed). More...

int get_num_total_outputs () const
Returns the total dimension of all of the vector-valued output ports (as if they were muxed). More...

int num_cache_entries () const
Returns the number nc of cache entries currently allocated in this System. More...

const CacheEntryget_cache_entry (CacheIndex index) const
Return a reference to a CacheEntry given its index. More...

void CheckValidContext (const ContextBase &context) const
Checks whether the given context is valid for this System and throws an exception with a helpful message if not. More...

SystemBase (const SystemBase &)=delete

SystemBaseoperator= (const SystemBase &)=delete

SystemBase (SystemBase &&)=delete

SystemBaseoperator= (SystemBase &&)=delete

const AbstractValueEvalAbstractInput (const ContextBase &context, int port_index) const
Returns the value of the input port with the given port_index as an AbstractValue, which is permitted for ports of any type. More...

template<typename V >
const V * EvalInputValue (const ContextBase &context, int port_index) const
Returns the value of an abstract-valued input port with the given port_index as a value of known type V. More...

const CacheEntryDeclareCacheEntry (std::string description, CacheEntry::AllocCallback alloc_function, CacheEntry::CalcCallback calc_function, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
Declares a new CacheEntry in this System using the least-restrictive definitions for the associated functions. More...

template<class MySystem , class MyContext , typename ValueType >
const CacheEntryDeclareCacheEntry (std::string description, ValueType(MySystem::*make)() const, void(MySystem::*calc)(const MyContext &, ValueType *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
Declares a cache entry by specifying member functions to use both for the allocator and calculator. More...

template<class MySystem , class MyContext , typename ValueType >
const CacheEntryDeclareCacheEntry (std::string description, const ValueType &model_value, void(MySystem::*calc)(const MyContext &, ValueType *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
Declares a cache entry by specifying a model value of concrete type ValueType and a calculator function that is a class member function (method) with signature: More...

template<class MySystem , class MyContext , typename ValueType >
const CacheEntryDeclareCacheEntry (std::string description, const ValueType &model_value, ValueType(MySystem::*calc)(const MyContext &) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
Declares a cache entry by specifying a model value of concrete type ValueType and a calculator function that is a class member function (method) with signature: More...

template<class MySystem , class MyContext , typename ValueType >
const CacheEntryDeclareCacheEntry (std::string description, void(MySystem::*calc)(const MyContext &, ValueType *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
Declares a cache entry by specifying only a calculator function that is a class member function (method) with signature: More...

template<class MySystem , class MyContext , typename ValueType >
const CacheEntryDeclareCacheEntry (std::string description, ValueType(MySystem::*calc)(const MyContext &) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
Declares a cache entry by specifying only a calculator function that is a class member function (method) with signature: More...

DependencyTicket discrete_state_ticket (DiscreteStateIndex index) const
Returns a ticket indicating dependence on a particular discrete state variable xdáµ¢ (may be a vector). More...

DependencyTicket abstract_state_ticket (AbstractStateIndex index) const
Returns a ticket indicating dependence on a particular abstract state variable xaáµ¢. More...

DependencyTicket numeric_parameter_ticket (NumericParameterIndex index) const
Returns a ticket indicating dependence on a particular numeric parameter pnáµ¢ (may be a vector). More...

DependencyTicket abstract_parameter_ticket (AbstractParameterIndex index) const
Returns a ticket indicating dependence on a particular abstract parameter paáµ¢. More...

DependencyTicket input_port_ticket (InputPortIndex index)
Returns a ticket indicating dependence on input port uáµ¢ indicated by index. More...

DependencyTicket cache_entry_ticket (CacheIndex index)
Returns a ticket indicating dependence on the cache entry indicated by index. More...

DependencyTicket output_port_ticket (OutputPortIndex index)
(Internal use only) Returns a ticket indicating dependence on the output port indicated by index. More...

int num_discrete_state_groups () const
Returns the number of declared discrete state groups (each group is a vector-valued discrete state variable). More...

int num_abstract_states () const
Returns the number of declared abstract state variables. More...

int num_numeric_parameters () const
Returns the number of declared numeric parameters (each of these is a vector-valued parameter). More...

int num_abstract_parameters () const
Returns the number of declared abstract parameters. More...

## Static Public Member Functions

static std::unique_ptr< AffineSystem< T > > MakeAffineSystem (const Eigen::Ref< const VectorX< symbolic::Expression >> &dynamics, const Eigen::Ref< const VectorX< symbolic::Expression >> &output, const Eigen::Ref< const VectorX< symbolic::Variable >> &state_vars, const Eigen::Ref< const VectorX< symbolic::Variable >> &input_vars, double time_period=0.0)
Creates a unique pointer to AffineSystem<T> by decomposing dynamics and outputs using state_vars and input_vars. More...

Static Public Member Functions inherited from System< T >
template<template< typename > class S = ::drake::systems::System>
static std::unique_ptr< S< AutoDiffXd > > ToAutoDiffXd (const S< T > &from)
Creates a deep copy of from, transmogrified to use the autodiff scalar type, with a dynamic-sized vector of partial derivatives. More...

template<template< typename > class S = ::drake::systems::System>
static std::unique_ptr< S< symbolic::Expression > > ToSymbolic (const S< T > &from)
Creates a deep copy of from, transmogrified to use the symbolic scalar type. More...

Static Public Member Functions inherited from SystemBase
static DependencyTicket nothing_ticket ()
Returns a ticket indicating that a computation does not depend on any source value; that is, it is a constant. More...

static DependencyTicket time_ticket ()
Returns a ticket indicating dependence on time. More...

static DependencyTicket accuracy_ticket ()
Returns a ticket indicating dependence on the accuracy setting in the Context. More...

static DependencyTicket q_ticket ()
Returns a ticket indicating that a computation depends on configuration state variables q. More...

static DependencyTicket v_ticket ()
Returns a ticket indicating dependence on velocity state variables v. More...

static DependencyTicket z_ticket ()
Returns a ticket indicating dependence on any or all of the miscellaneous continuous state variables z. More...

static DependencyTicket xc_ticket ()
Returns a ticket indicating dependence on all of the continuous state variables q, v, or z. More...

static DependencyTicket xd_ticket ()
Returns a ticket indicating dependence on all of the numerical discrete state variables, in any discrete variable group. More...

static DependencyTicket xa_ticket ()
Returns a ticket indicating dependence on all of the abstract state variables in the current Context. More...

static DependencyTicket all_state_ticket ()
Returns a ticket indicating dependence on all state variables x in this system, including continuous variables xc, discrete (numeric) variables xd, and abstract state variables xa. More...

static DependencyTicket pn_ticket ()
Returns a ticket indicating dependence on all of the numerical parameters in the current Context. More...

static DependencyTicket pa_ticket ()
Returns a ticket indicating dependence on all of the abstract parameters pa in the current Context. More...

static DependencyTicket all_parameters_ticket ()
Returns a ticket indicating dependence on all parameters p in this system, including numeric parameters pn, and abstract parameters pa. More...

static DependencyTicket all_input_ports_ticket ()
Returns a ticket indicating dependence on all input ports u of this system. More...

static DependencyTicket all_sources_ticket ()
Returns a ticket indicating dependence on every possible independent source value, including time, accuracy, state, input ports, and parameters (but not cache entries). More...

static DependencyTicket configuration_ticket ()
Returns a ticket indicating dependence on all source values that may affect configuration-dependent computations. More...

static DependencyTicket kinematics_ticket ()
Returns a ticket indicating dependence on all source values that may affect configuration- or velocity-dependent computations. More...

static DependencyTicket xcdot_ticket ()
Returns a ticket for the cache entry that holds time derivatives of the continuous variables. More...

static DependencyTicket pe_ticket ()
Returns a ticket for the cache entry that holds the potential energy calculation. More...

static DependencyTicket ke_ticket ()
Returns a ticket for the cache entry that holds the kinetic energy calculation. More...

static DependencyTicket pc_ticket ()
Returns a ticket for the cache entry that holds the conservative power calculation. More...

static DependencyTicket pnc_ticket ()
Returns a ticket for the cache entry that holds the non-conservative power calculation. More...

## Protected Member Functions

AffineSystem (SystemScalarConverter converter, const Eigen::Ref< const Eigen::MatrixXd > &A, const Eigen::Ref< const Eigen::MatrixXd > &B, const Eigen::Ref< const Eigen::VectorXd > &f0, const Eigen::Ref< const Eigen::MatrixXd > &C, const Eigen::Ref< const Eigen::MatrixXd > &D, const Eigen::Ref< const Eigen::VectorXd > &y0, double time_period)
Constructor that specifies scalar-type conversion support. More...

Protected Member Functions inherited from TimeVaryingAffineSystem< T >
TimeVaryingAffineSystem (SystemScalarConverter converter, int num_states, int num_inputs, int num_outputs, double time_period)
Constructor. More...

Protected Member Functions inherited from LeafSystem< T >
LeafSystem ()
Default constructor that declares no inputs, outputs, state, parameters, events, nor scalar-type conversion support (AutoDiff, etc.). More...

LeafSystem (SystemScalarConverter converter)
Constructor that declares no inputs, outputs, state, parameters, or events, but allows subclasses to declare scalar-type conversion support (AutoDiff, etc.). More...

virtual std::unique_ptr< LeafContext< T > > DoMakeLeafContext () const
Provides a new instance of the leaf context for this system. More...

virtual void DoValidateAllocatedLeafContext (const LeafContext< T > &context) const
Derived classes that impose restrictions on what resources are permitted should check those restrictions by implementing this. More...

T DoCalcWitnessValue (const Context< T > &context, const WitnessFunction< T > &witness_func) const final
Derived classes will implement this method to evaluate a witness function at the given context. More...

void AddTriggeredWitnessFunctionToCompositeEventCollection (Event< T > *event, CompositeEventCollection< T > *events) const final
Add event to events due to a witness function triggering. More...

void DoCalcNextUpdateTime (const Context< T > &context, CompositeEventCollection< T > *events, T *time) const override
Computes the next update time based on the configured periodic events, for scalar types that are arithmetic, or aborts for scalar types that are not arithmetic. More...

BasicVector< T > * DoAllocateInputVector (const InputPort< T > &input_port) const override
Allocates a vector that is suitable as an input value for input_port. More...

AbstractValueDoAllocateInputAbstract (const InputPort< T > &input_port) const override
Allocates an AbstractValue suitable as an input value for input_port. More...

void GetGraphvizFragment (int max_depth, std::stringstream *dot) const override
Emits a graphviz fragment for this System. More...

void GetGraphvizInputPortToken (const InputPort< T > &port, int max_depth, std::stringstream *dot) const final
Appends a fragment to the dot stream identifying the graphviz node representing port. More...

void GetGraphvizOutputPortToken (const OutputPort< T > &port, int max_depth, std::stringstream *dot) const final
Appends a fragment to the dot stream identifying the graphviz node representing port. More...

virtual std::unique_ptr< ContinuousState< T > > AllocateContinuousState () const
Returns a ContinuousState used to implement both CreateDefaultContext and AllocateTimeDerivatives. More...

virtual std::unique_ptr< DiscreteValues< T > > AllocateDiscreteState () const
Reserves the discrete state as required by CreateDefaultContext. More...

virtual std::unique_ptr< AbstractValuesAllocateAbstractState () const
Reserves the abstract state as required by CreateDefaultContext. More...

virtual std::unique_ptr< Parameters< T > > AllocateParameters () const
Reserves the parameters as required by CreateDefaultContext. More...

virtual optional< boolDoHasDirectFeedthrough (int input_port, int output_port) const
Returns true if there is direct-feedthrough from the given input_port to the given output_port, false if there is not direct-feedthrough, or nullopt if unknown (in which case SystemSymbolicInspector will attempt to measure the feedthrough using symbolic form). More...

int DeclareNumericParameter (const BasicVector< T > &model_vector)
Declares a numeric parameter using the given model_vector. More...

template<template< typename > class U = BasicVector>
const U< T > & GetNumericParameter (const Context< T > &context, int index) const
Extracts the numeric parameters of type U from the context at index. More...

template<template< typename > class U = BasicVector>
U< T > & GetMutableNumericParameter (Context< T > *context, int index) const
Extracts the numeric parameters of type U from the context at index. More...

int DeclareAbstractParameter (const AbstractValue &model_value)
Declares an abstract parameter using the given model_value. More...

template<typename EventType >
void DeclarePeriodicEvent (double period_sec, double offset_sec)
Declares that this System has a simple, fixed-period event specified with no custom callback function, and its attribute field contains an Event<T>::PeriodicAttribute constructed from the specified period_sec and offset_sec. More...

template<typename EventType >
void DeclarePeriodicEvent (double period_sec, double offset_sec, const EventType &event)
Declares that this System has a simple, fixed-period event specified by event. More...

void DeclarePeriodicDiscreteUpdate (double period_sec, double offset_sec=0)
Declares a periodic discrete update event with period = period_sec and offset = offset_sec. More...

void DeclarePeriodicUnrestrictedUpdate (double period_sec, double offset_sec=0)
Declares a periodic unrestricted update event with period = period_sec and offset = offset_sec. More...

void DeclarePeriodicPublish (double period_sec, double offset_sec=0)
Declares a periodic publish event with period = period_sec and offset = offset_sec. More...

template<typename EventType >
void DeclarePerStepEvent (const EventType &event)
Declares a per-step event using event, which is deep copied (the copy is maintained by this). More...

template<typename EventType >
void DeclareInitializationEvent (const EventType &event)
Declares an initialization event by deep copying event and storing it internally. More...

void DeclareContinuousState (int num_state_variables)
Declares that this System should reserve continuous state with num_state_variables state variables, which have no second-order structure. More...

void DeclareContinuousState (int num_q, int num_v, int num_z)
Declares that this System should reserve continuous state with num_q generalized positions, num_v generalized velocities, and num_z miscellaneous state variables. More...

void DeclareContinuousState (const BasicVector< T > &model_vector)
Declares that this System should reserve continuous state with model_vector.size() miscellaneous state variables, stored in a vector Cloned from model_vector. More...

void DeclareContinuousState (const BasicVector< T > &model_vector, int num_q, int num_v, int num_z)
Declares that this System should reserve continuous state with num_q generalized positions, num_v generalized velocities, and num_z miscellaneous state variables, stored in a vector Cloned from model_vector. More...

void DeclareContinuousState (std::unique_ptr< BasicVector< T >> model_vector, int num_q, int num_v, int num_z)
Declares that this System should reserve continuous state with num_q generalized positions, num_v generalized velocities, and num_z miscellaneous state variables, stored in the a vector Cloned from model_vector. More...

void DeclareDiscreteState (int num_state_variables)
Declares that this System should reserve discrete state with num_state_variables state variables. More...

int DeclareAbstractState (std::unique_ptr< AbstractValue > abstract_state)
Declares an abstract state. More...

template<class MySystem >
SystemConstraintIndex DeclareEqualityConstraint (void(MySystem::*calc)(const Context< T > &, VectorX< T > *) const, int count, const std::string &description)
Declares a system constraint of the form f(context) = 0 by specifying a member function to use to calculate the (VectorX) constraint value with a signature: More...

SystemConstraintIndex DeclareEqualityConstraint (typename SystemConstraint< T >::CalcCallback calc, int count, const std::string &description)
Declares a system constraint of the form f(context) = 0 by specifying a std::function to use to calculate the (Vector) constraint value with a signature: More...

template<class MySystem >
SystemConstraintIndex DeclareInequalityConstraint (void(MySystem::*calc)(const Context< T > &, VectorX< T > *) const, int count, const std::string &description)
Declares a system constraint of the form f(context) â‰¥ 0 by specifying a member function to use to calculate the (VectorX) constraint value with a signature: More...

SystemConstraintIndex DeclareInequalityConstraint (typename SystemConstraint< T >::CalcCallback calc, int count, const std::string &description)
Declares a system constraint of the form f(context) â‰¥ 0 by specifying a std::function to use to calculate the (Vector) constraint value with a signature: More...

virtual void DoPublish (const Context< T > &context, const std::vector< const PublishEvent< T > *> &events) const
Derived-class event handler for all simultaneous publish events in events. More...

virtual void DoCalcUnrestrictedUpdate (const Context< T > &context, const std::vector< const UnrestrictedUpdateEvent< T > *> &events, State< T > *state) const
Derived-class event handler for all simultaneous unrestricted update events. More...

const InputPort< T > & DeclareVectorInputPort (std::string name, const BasicVector< T > &model_vector, optional< RandomDistribution > random_type=nullopt)
Declares a vector-valued input port using the given model_vector. More...

const InputPort< T > & DeclareAbstractInputPort (std::string name, const AbstractValue &model_value)
Declares an abstract-valued input port using the given model_value. More...

const InputPort< T > & DeclareVectorInputPort (const BasicVector< T > &model_vector, optional< RandomDistribution > random_type=nullopt)
See the nearly identical signature with an additional (first) argument specifying the port name. More...

const InputPort< T > & DeclareAbstractInputPort (const AbstractValue &model_value)
See the nearly identical signature with an additional (first) argument specifying the port name. More...

template<class MySystem , typename BasicVectorSubtype >
const OutputPort< T > & DeclareVectorOutputPort (std::string name, const BasicVectorSubtype &model_vector, void(MySystem::*calc)(const Context< T > &, BasicVectorSubtype *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
Declares a vector-valued output port by specifying (1) a model vector of type BasicVectorSubtype derived from BasicVector and initialized to the correct size and desired initial value, and (2) a calculator function that is a class member function (method) with signature: More...

template<class MySystem , typename BasicVectorSubtype >
const OutputPort< T > & DeclareVectorOutputPort (std::string name, void(MySystem::*calc)(const Context< T > &, BasicVectorSubtype *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
Declares a vector-valued output port by specifying only a calculator function that is a class member function (method) with signature: More...

const OutputPort< T > & DeclareVectorOutputPort (std::string name, const BasicVector< T > &model_vector, typename LeafOutputPort< T >::CalcVectorCallback vector_calc_function, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
(Advanced) Declares a vector-valued output port using the given model_vector and a function for calculating the port's value at runtime. More...

template<class MySystem , typename OutputType >
const OutputPort< T > & DeclareAbstractOutputPort (std::string name, const OutputType &model_value, void(MySystem::*calc)(const Context< T > &, OutputType *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
Declares an abstract-valued output port by specifying a model value of concrete type OutputType and a calculator function that is a class member function (method) with signature: More...

template<class MySystem , typename OutputType >
const OutputPort< T > & DeclareAbstractOutputPort (std::string name, void(MySystem::*calc)(const Context< T > &, OutputType *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
Declares an abstract-valued output port by specifying only a calculator function that is a class member function (method) with signature: More...

template<class MySystem , typename OutputType >
const OutputPort< T > & DeclareAbstractOutputPort (std::string name, OutputType(MySystem::*make)() const, void(MySystem::*calc)(const Context< T > &, OutputType *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
Declares an abstract-valued output port by specifying member functions to use both for the allocator and calculator. More...

const OutputPort< T > & DeclareAbstractOutputPort (std::string name, typename LeafOutputPort< T >::AllocCallback alloc_function, typename LeafOutputPort< T >::CalcCallback calc_function, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
(Advanced) Declares an abstract-valued output port using the given allocator and calculator functions provided in their most generic forms. More...

template<class MySystem , typename BasicVectorSubtype >
const OutputPort< T > & DeclareVectorOutputPort (const BasicVectorSubtype &model_vector, void(MySystem::*calc)(const Context< T > &, BasicVectorSubtype *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
See the nearly identical signature with an additional (first) argument specifying the port name. More...

template<class MySystem , typename BasicVectorSubtype >
const OutputPort< T > & DeclareVectorOutputPort (void(MySystem::*calc)(const Context< T > &, BasicVectorSubtype *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
See the nearly identical signature with an additional (first) argument specifying the port name. More...

const OutputPort< T > & DeclareVectorOutputPort (const BasicVector< T > &model_vector, typename LeafOutputPort< T >::CalcVectorCallback vector_calc_function, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
See the nearly identical signature with an additional (first) argument specifying the port name. More...

template<class MySystem , typename OutputType >
std::enable_if_t<!std::is_same< OutputType, std::string >::value, const OutputPort< T > & > DeclareAbstractOutputPort (const OutputType &model_value, void(MySystem::*calc)(const Context< T > &, OutputType *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
See the nearly identical signature with an additional (first) argument specifying the port name. More...

template<class MySystem , typename OutputType >
const OutputPort< T > & DeclareAbstractOutputPort (void(MySystem::*calc)(const Context< T > &, OutputType *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
See the nearly identical signature with an additional (first) argument specifying the port name. More...

template<class MySystem , typename OutputType >
const OutputPort< T > & DeclareAbstractOutputPort (OutputType(MySystem::*make)() const, void(MySystem::*calc)(const Context< T > &, OutputType *) const, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
See the nearly identical signature with an additional (first) argument specifying the port name. More...

const OutputPort< T > & DeclareAbstractOutputPort (typename LeafOutputPort< T >::AllocCallback alloc_function, typename LeafOutputPort< T >::CalcCallback calc_function, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
See the nearly identical signature with an additional (first) argument specifying the port name. More...

template<class MySystem >
std::unique_ptr< WitnessFunction< T > > DeclareWitnessFunction (const std::string &description, const WitnessFunctionDirection &direction_type, T(MySystem::*calc)(const Context< T > &) const) const
Constructs the witness function with the given description (used primarily for debugging and logging), direction type, and calculator function; and with no event object. More...

std::unique_ptr< WitnessFunction< T > > DeclareWitnessFunction (const std::string &description, const WitnessFunctionDirection &direction_type, std::function< T(const Context< T > &)> calc) const
Constructs the witness function with the given description (used primarily for debugging and logging), direction type, and calculator function; and with no event object. More...

template<class MySystem >
std::unique_ptr< WitnessFunction< T > > DeclareWitnessFunction (const std::string &description, const WitnessFunctionDirection &direction_type, T(MySystem::*calc)(const Context< T > &) const, void(MySystem::*publish_callback)(const Context< T > &, const PublishEvent< T > &) const) const
Constructs the witness function with the given description (used primarily for debugging and logging), direction type, calculator function, and publish event callback function for when this triggers. More...

template<class MySystem >
std::unique_ptr< WitnessFunction< T > > DeclareWitnessFunction (const std::string &description, const WitnessFunctionDirection &direction_type, T(MySystem::*calc)(const Context< T > &) const, void(MySystem::*du_callback)(const Context< T > &, const DiscreteUpdateEvent< T > &, DiscreteValues< T > *) const) const
Constructs the witness function with the given description (used primarily for debugging and logging), direction type, calculator function, and discrete update event callback function for when this triggers. More...

template<class MySystem >
std::unique_ptr< WitnessFunction< T > > DeclareWitnessFunction (const std::string &description, const WitnessFunctionDirection &direction_type, T(MySystem::*calc)(const Context< T > &) const, void(MySystem::*uu_callback)(const Context< T > &, const UnrestrictedUpdateEvent< T > &, State< T > *) const) const
Constructs the witness function with the given description (used primarily for debugging and logging), direction type, calculator function, and unrestricted update event callback function for when this triggers. More...

template<class MySystem >
std::unique_ptr< WitnessFunction< T > > DeclareWitnessFunction (const std::string &description, const WitnessFunctionDirection &direction_type, T(MySystem::*calc)(const Context< T > &) const, const Event< T > &e) const
Constructs the witness function with the given description (used primarily for debugging and logging), direction type, and calculator function, and with an object corresponding to the event that is to be dispatched when this witness function triggers. More...

std::unique_ptr< WitnessFunction< T > > DeclareWitnessFunction (const std::string &description, const WitnessFunctionDirection &direction_type, std::function< T(const Context< T > &)> calc, const Event< T > &e) const
Constructs the witness function with the given description (used primarily for debugging and logging), direction type, and calculator function, and with an object corresponding to the event that is to be dispatched when this witness function triggers. More...

Protected Member Functions inherited from System< T >
virtual void DoGetWitnessFunctions (const Context< T > &, std::vector< const WitnessFunction< T > *> *) const
Derived classes can override this method to provide witness functions active for the given state. More...

SystemConstraintIndex AddConstraint (std::unique_ptr< SystemConstraint< T >> constraint)
Adds an already-created constraint to the list of constraints for this System. More...

const EventCollection< PublishEvent< T > > & get_forced_publish_events () const

const EventCollection< DiscreteUpdateEvent< T > > & get_forced_discrete_update_events () const

const EventCollection< UnrestrictedUpdateEvent< T > > & get_forced_unrestricted_update_events () const

void set_forced_publish_events (std::unique_ptr< EventCollection< PublishEvent< T >>> forced)

void set_forced_discrete_update_events (std::unique_ptr< EventCollection< DiscreteUpdateEvent< T >>> forced)

void set_forced_unrestricted_update_events (std::unique_ptr< EventCollection< UnrestrictedUpdateEvent< T >>> forced)

System (SystemScalarConverter converter)
Constructs an empty System base class object and allocates base class resources, possibly supporting scalar-type conversion support (AutoDiff, etc.) using converter. More...

const InputPort< T > & DeclareInputPort (std::string name, PortDataType type, int size, optional< RandomDistribution > random_type=nullopt)
Adds a port with the specified type and size to the input topology. More...

const InputPort< T > & DeclareAbstractInputPort (std::string name)
Adds an abstract-valued port to the input topology. More...

const InputPort< T > & DeclareInputPort (PortDataType type, int size, optional< RandomDistribution > random_type=nullopt)
See the nearly identical signature with an additional (first) argument specifying the port name. More...

const InputPort< T > & DeclareAbstractInputPort ()
See the nearly identical signature with an argument specifying the port name. More...

virtual T DoCalcPotentialEnergy (const Context< T > &context) const
Override this method for physical systems to calculate the potential energy PE currently stored in the configuration provided in the given Context. More...

virtual T DoCalcKineticEnergy (const Context< T > &context) const
Override this method for physical systems to calculate the kinetic energy KE currently present in the motion provided in the given Context. More...

virtual T DoCalcConservativePower (const Context< T > &context) const
Override this method to return the rate Pc at which mechanical energy is being converted from potential energy to kinetic energy by this system in the given Context. More...

virtual T DoCalcNonConservativePower (const Context< T > &context) const
Override this method to return the rate Pnc at which work W is done on the system by non-conservative forces. More...

virtual void DoMapQDotToVelocity (const Context< T > &context, const Eigen::Ref< const VectorX< T >> &qdot, VectorBase< T > *generalized_velocity) const
Provides the substantive implementation of MapQDotToVelocity(). More...

virtual void DoMapVelocityToQDot (const Context< T > &context, const Eigen::Ref< const VectorX< T >> &generalized_velocity, VectorBase< T > *qdot) const
Provides the substantive implementation of MapVelocityToQDot(). More...

virtual int do_get_num_constraint_equations (const Context< T > &context) const
Gets the number of constraint equations for this system from the given context. More...

virtual Eigen::VectorXd DoEvalConstraintEquations (const Context< T > &context) const
Evaluates the constraint equations for the system at the generalized coordinates and generalized velocity specified by the context. More...

virtual Eigen::VectorXd DoEvalConstraintEquationsDot (const Context< T > &context) const
Computes the time derivative of each constraint equation, evaluated at the generalized coordinates and generalized velocity specified by the context. More...

virtual Eigen::VectorXd DoCalcVelocityChangeFromConstraintImpulses (const Context< T > &context, const Eigen::MatrixXd &J, const Eigen::VectorXd &lambda) const
Computes the change in velocity from applying the given constraint forces to the system at the given context. More...

virtual double DoCalcConstraintErrorNorm (const Context< T > &context, const Eigen::VectorXd &error) const
Computes the norm of the constraint error. More...

Eigen::VectorBlock< VectorX< T > > GetMutableOutputVector (SystemOutput< T > *output, int port_index) const
Returns a mutable Eigen expression for a vector valued output port with index port_index in this system. More...

Protected Member Functions inherited from SystemBase
SystemBase ()=default
(Internal use only) Default constructor. More...

void AddInputPort (std::unique_ptr< InputPortBase > port)
(Internal use only) Adds an already-constructed input port to this System. More...

void AddOutputPort (std::unique_ptr< OutputPortBase > port)
(Internal use only) Adds an already-constructed output port to this System. More...

std::string NextInputPortName (std::string given_name) const
(Internal use only) Returns a name for the next input port, using the given name if it isn't kUseDefaultName, otherwise making up a name like "u3" from the next available input port index. More...

std::string NextOutputPortName (std::string given_name) const
(Internal use only) Returns a name for the next output port, using the given name if it isn't kUseDefaultName, otherwise making up a name like "y3" from the next available output port index. More...

(Internal use only) Assigns a ticket to a new discrete variable group with the given index. More...

(Internal use only) Assigns a ticket to a new abstract state variable with the given index. More...

(Internal use only) Assigns a ticket to a new numeric parameter with the given index. More...

(Internal use only) Assigns a ticket to a new abstract parameter with the given index. More...

const CacheEntryDeclareCacheEntryWithKnownTicket (DependencyTicket known_ticket, std::string description, CacheEntry::AllocCallback alloc_function, CacheEntry::CalcCallback calc_function, std::set< DependencyTicket > prerequisites_of_calc={ all_sources_ticket()})
(Internal use only) This is for cache entries associated with pre-defined tickets, for example the cache entry for time derivatives. More...

const internal::SystemParentServiceInterface * get_parent_service () const
Returns a pointer to the service interface of the immediately enclosing Diagram if one has been set, otherwise nullptr. More...

DependencyTicket assign_next_dependency_ticket ()
(Internal use only) Assigns the next unused dependency ticket number, unique only within a particular system. More...

const AbstractValueEvalAbstractInputImpl (const char *func, const ContextBase &context, InputPortIndex port_index) const
(Internal use only) Shared code for updating an input port and returning a pointer to its abstract value, or nullptr if the port is not connected. More...

void ThrowNegativePortIndex (const char *func, int port_index) const
Throws std::out_of_range to report a negative port_index that was passed to API method func. More...

void ThrowInputPortIndexOutOfRange (const char *func, InputPortIndex port_index) const
Throws std::out_of_range to report bad input port_index that was passed to API method func. More...

void ThrowOutputPortIndexOutOfRange (const char *func, OutputPortIndex port_index) const
Throws std::out_of_range to report bad output port_index that was passed to API method func. More...

void ThrowNotAVectorInputPort (const char *func, InputPortIndex port_index) const
Throws std::logic_error because someone misused API method func, that is only allowed for declared-vector input ports, on an abstract port whose index is given here. More...

void ThrowInputPortHasWrongType (const char *func, InputPortIndex port_index, const std::string &expected_type, const std::string &actual_type) const
Throws std::logic_error because someone called API method func claiming the input port had some value type that was wrong. More...

void ThrowCantEvaluateInputPort (const char *func, InputPortIndex port_index) const
Throws std::logic_error because someone called API method func, that requires this input port to be evaluatable, but the port was neither fixed nor connected. More...

const InputPortBaseGetInputPortBaseOrThrow (const char *func, int port_index) const
(Internal use only) Returns the InputPortBase at index port_index, throwing std::out_of_range we don't like the port index. More...

const OutputPortBaseGetOutputPortBaseOrThrow (const char *func, int port_index) const
(Internal use only) Returns the OutputPortBase at index port_index, throwing std::out_of_range we don't like the port index. More...

void InitializeContextBase (ContextBase *context) const
This method must be invoked from within derived class DoAllocateContext() implementations right after the concrete Context object has been allocated. More...

Static Protected Member Functions inherited from SystemBase
static void set_parent_service (SystemBase *child, const internal::SystemParentServiceInterface *parent_service)
(Internal use only) Declares that parent_service is the service interface of the Diagram that owns this subsystem. More...

## Detailed Description

### template<typename T> class drake::systems::AffineSystem< T >

A discrete OR continuous affine system (with constant coefficients).

 u(t) →
AffineSystem
 → y(t)

Let u denote the input vector, x denote the state vector, and y denote the output vector.

If time_period > 0.0, the affine system will have the following discrete-time state update:

$x(t+h) = A x(t) + B u(t) + f_0,$

where h is the time_period. If time_period == 0.0, the affine system will have the following continuous-time state update:

$\dot{x} = A x + B u + f_0.$

In both cases, the system will have the output:

$y = C x + D u + y_0,$

Template Parameters
 T The scalar element type, which must be a valid Eigen scalar.

Instantiated templates for the following kinds of T's are provided:

They are already available to link against in the containing library. No other values for T are currently supported.

LinearSystem
MatrixGain

## ◆ AffineSystem() [1/5]

 AffineSystem ( const AffineSystem< T > & )
delete

## ◆ AffineSystem() [2/5]

 AffineSystem ( AffineSystem< T > && )
delete

## ◆ AffineSystem() [3/5]

 AffineSystem ( const Eigen::Ref< const Eigen::MatrixXd > & A, const Eigen::Ref< const Eigen::MatrixXd > & B, const Eigen::Ref< const Eigen::VectorXd > & f0, const Eigen::Ref< const Eigen::MatrixXd > & C, const Eigen::Ref< const Eigen::MatrixXd > & D, const Eigen::Ref< const Eigen::VectorXd > & y0, double time_period = 0.0 )

Constructs an Affine system with a fixed set of coefficient matrices A, B,C, and D as well as fixed initial velocity offset xDot0 and output offset y0.

The coefficient matrices must obey the following dimensions :

Matrix Num Rows Num Columns
A num states num states
B num states num inputs
C num outputs num states
D num outputs num inputs
Parameters
 time_period Defines the period of the discrete time system; use time_period=0.0 to denote a continuous time system. Default: 0.0

Subclasses must use the protected constructor, not this one.

## ◆ AffineSystem() [4/5]

 AffineSystem ( const AffineSystem< U > & other )
explicit

Scalar-converting copy constructor. See System Scalar Conversion.

## ◆ AffineSystem() [5/5]

 AffineSystem ( SystemScalarConverter converter, const Eigen::Ref< const Eigen::MatrixXd > & A, const Eigen::Ref< const Eigen::MatrixXd > & B, const Eigen::Ref< const Eigen::VectorXd > & f0, const Eigen::Ref< const Eigen::MatrixXd > & C, const Eigen::Ref< const Eigen::MatrixXd > & D, const Eigen::Ref< const Eigen::VectorXd > & y0, double time_period )
protected

Constructor that specifies scalar-type conversion support.

Parameters
 converter scalar-type conversion support helper (i.e., AutoDiff, etc.); pass a default-constructed object if such support is not desired. See System Scalar Conversion for detailed background and examples related to scalar-type conversion support.

## ◆ A() [1/2]

 const Eigen::MatrixXd& A ( ) const
inline

## ◆ A() [2/2]

 MatrixX A ( const T & ) const
inlinefinalvirtual

## ◆ B() [1/2]

 const Eigen::MatrixXd& B ( ) const
inline

## ◆ B() [2/2]

 MatrixX B ( const T & ) const
inlinefinalvirtual

## ◆ C() [1/2]

 const Eigen::MatrixXd& C ( ) const
inline

## ◆ C() [2/2]

 MatrixX C ( const T & ) const
inlinefinalvirtual

## ◆ D() [1/2]

 const Eigen::MatrixXd& D ( ) const
inline

## ◆ D() [2/2]

 MatrixX D ( const T & ) const
inlinefinalvirtual

## ◆ f0() [1/2]

 const Eigen::VectorXd& f0 ( ) const
inline

## ◆ f0() [2/2]

 VectorX f0 ( const T & ) const
inlinefinalvirtual

## ◆ MakeAffineSystem()

 unique_ptr< AffineSystem< T > > MakeAffineSystem ( const Eigen::Ref< const VectorX< symbolic::Expression >> & dynamics, const Eigen::Ref< const VectorX< symbolic::Expression >> & output, const Eigen::Ref< const VectorX< symbolic::Variable >> & state_vars, const Eigen::Ref< const VectorX< symbolic::Variable >> & input_vars, double time_period = 0.0 )
static

Creates a unique pointer to AffineSystem<T> by decomposing dynamics and outputs using state_vars and input_vars.

Exceptions
 std::runtime_error if either dynamics or outputs is not affine in state_vars and input_vars.

## ◆ operator=() [1/2]

 AffineSystem& operator= ( AffineSystem< T > && )
delete

## ◆ operator=() [2/2]

 AffineSystem& operator= ( const AffineSystem< T > & )
delete

## ◆ y0() [1/2]

 const Eigen::VectorXd& y0 ( ) const
inline

## ◆ y0() [2/2]

 VectorX y0 ( const T & ) const
inlinefinalvirtual

The documentation for this class was generated from the following files: