Drake
DiscreteValues< T > Class Template Reference

DiscreteValues is a container for numerical but non-continuous state and parameters. More...

#include <drake/systems/framework/discrete_values.h>

## Public Member Functions

DiscreteValues ()
Constructs an empty DiscreteValues object containing no groups. More...

DiscreteValues (const std::vector< BasicVector< T > *> &data)
Constructs a DiscreteValues that does not own the underlying data. More...

DiscreteValues (std::vector< std::unique_ptr< BasicVector< T >>> &&data)
Constructs a DiscreteValues that owns the underlying data. More...

DiscreteValues (std::unique_ptr< BasicVector< T >> datum)
Constructs a one-group DiscreteValues object that owns a single datum vector which may not be null. More...

int AppendGroup (std::unique_ptr< BasicVector< T >> datum)
Adds an additional group that owns the given datum, which must be non-null. More...

virtual ~DiscreteValues ()

int num_groups () const

const std::vector< BasicVector< T > * > & get_data () const

const BasicVector< T > & get_vector (int index) const
Returns a const reference to the vector holding data for the indicated group. More...

BasicVector< T > & get_mutable_vector (int index)
Returns a mutable reference to the vector holding data for the indicated group. More...

void CopyFrom (const DiscreteValues< T > &other)
Writes the values from other into this DiscreteValues, possibly writing through to unowned data. More...

void SetFrom (const DiscreteValues< double > &other)
Resets the values in this DiscreteValues from the values in other, possibly writing through to unowned data. More...

std::unique_ptr< DiscreteValues< T > > Clone () const
Creates a deep copy of this object with the same substructure but with all data owned by the copy. More...

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

DiscreteValuesoperator= (const DiscreteValues &)=delete

DiscreteValues (DiscreteValues &&)=delete

DiscreteValuesoperator= (DiscreteValues &&)=delete

Convenience accessors for DiscreteValues with just one group.

These will fail (at least in Debug builds) if there is more than one group in this DiscreteValues object.

int size () const
Returns the number of elements in the only DiscreteValues group. More...

T & operator[] (std::size_t idx)
Returns a mutable reference to an element in the only group. More...

const T & operator[] (std::size_t idx) const
Returns a const reference to an element in the only group. More...

const BasicVector< T > & get_vector () const
Returns a const reference to the BasicVector containing the values for the only group. More...

BasicVector< T > & get_mutable_vector ()
Returns a mutable reference to the BasicVector containing the values for the only group. More...

## Detailed Description

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

DiscreteValues is a container for numerical but non-continuous state and parameters.

It may own its underlying data, for use with leaf Systems, or not, for use with Diagrams.

DiscreteValues is an ordered collection xd of BasicVector "groups" so xd = [xd₀, xd₁...], where each group xdᵢ is a contiguous vector. Requesting a specific group index from this collection is the most granular way to retrieve discrete values from the Context, and thus is the unit of cache invalidation. System authors are encouraged to partition their DiscreteValues such that each cacheable computation within the System may depend on only the elements of DiscreteValues that it needs.

None of the contained vectors (groups) may be null, although any of them may be zero-length.

Template Parameters
 T A mathematical type compatible with Eigen's Scalar.

## ◆ DiscreteValues() [1/6]

 DiscreteValues ( const DiscreteValues< T > & )
delete

## ◆ DiscreteValues() [2/6]

 DiscreteValues ( DiscreteValues< T > && )
delete

## ◆ DiscreteValues() [3/6]

 DiscreteValues ( )
inline

Constructs an empty DiscreteValues object containing no groups.

## ◆ DiscreteValues() [4/6]

 DiscreteValues ( const std::vector< BasicVector< T > *> & data )
inlineexplicit

Constructs a DiscreteValues that does not own the underlying data.

The referenced data must outlive this DiscreteValues. Every entry must be non-null.

## ◆ DiscreteValues() [5/6]

 DiscreteValues ( std::vector< std::unique_ptr< BasicVector< T >>> && data )
inlineexplicit

Constructs a DiscreteValues that owns the underlying data.

Every entry must be non-null.

## ◆ DiscreteValues() [6/6]

 DiscreteValues ( std::unique_ptr< BasicVector< T >> datum )
inlineexplicit

Constructs a one-group DiscreteValues object that owns a single datum vector which may not be null.

## ◆ ~DiscreteValues()

 virtual ~DiscreteValues ( )
inlinevirtual

## ◆ AppendGroup()

 int AppendGroup ( std::unique_ptr< BasicVector< T >> datum )
inline

Adds an additional group that owns the given datum, which must be non-null.

Returns the assigned group number, counting up from 0 for the first group.

## ◆ Clone()

 std::unique_ptr > Clone ( ) const
inline

Creates a deep copy of this object with the same substructure but with all data owned by the copy.

That is, if the original was a DiagramDiscreteValues object that maintains a tree of substates, the clone will not include any references to the original substates and is thus decoupled from the Context containing the original. The concrete type of the BasicVector underlying each leaf DiscreteValue is preserved.

## ◆ CopyFrom()

 void CopyFrom ( const DiscreteValues< T > & other )
inline

Writes the values from other into this DiscreteValues, possibly writing through to unowned data.

Asserts if the dimensions don't match.

## ◆ get_data()

 const std::vector*>& get_data ( ) const
inline

## ◆ get_mutable_vector() [1/2]

 BasicVector& get_mutable_vector ( )
inline

Returns a mutable reference to the BasicVector containing the values for the only group.

## ◆ get_mutable_vector() [2/2]

 BasicVector& get_mutable_vector ( int index )
inline

Returns a mutable reference to the vector holding data for the indicated group.

## ◆ get_vector() [1/2]

 const BasicVector& get_vector ( ) const
inline

Returns a const reference to the BasicVector containing the values for the only group.

## ◆ get_vector() [2/2]

 const BasicVector& get_vector ( int index ) const
inline

Returns a const reference to the vector holding data for the indicated group.

## ◆ num_groups()

 int num_groups ( ) const
inline

## ◆ operator=() [1/2]

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

## ◆ operator=() [2/2]

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

## ◆ operator[]() [1/2]

 T& operator[] ( std::size_t idx )
inline

Returns a mutable reference to an element in the only group.

## ◆ operator[]() [2/2]

 const T& operator[] ( std::size_t idx ) const
inline

Returns a const reference to an element in the only group.

## ◆ SetFrom()

 void SetFrom ( const DiscreteValues< double > & other )
inline

Resets the values in this DiscreteValues from the values in other, possibly writing through to unowned data.

Asserts if the dimensions don't match.

## ◆ size()

 int size ( ) const
inline

Returns the number of elements in the only DiscreteValues group.

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