nt::DoubleSubscriber Class Reference

NetworkTables Double subscriber. More...

#include <networktables/DoubleTopic.h>

Inheritance diagram for nt::DoubleSubscriber:

Public Types
using	TopicType = DoubleTopic
using	ValueType = double
using	ParamType = double
using	TimestampedValueType = TimestampedDouble

Public Member Functions
	DoubleSubscriber ()=default
	DoubleSubscriber (NT_Subscriber handle, ParamType defaultValue)
	Construct from a subscriber handle; recommended to use DoubleTopic::Subscribe() instead. More...
ValueType	Get () const
	Get the last published value. More...
ValueType	Get (ParamType defaultValue) const
	Get the last published value. More...
TimestampedValueType	GetAtomic () const
	Get the last published value along with its timestamp If no value has been published, returns the stored default value and a timestamp of 0. More...
TimestampedValueType	GetAtomic (ParamType defaultValue) const
	Get the last published value along with its timestamp. More...
std::vector< TimestampedValueType >	ReadQueue ()
	Get an array of all value changes since the last call to ReadQueue. More...
TopicType	GetTopic () const
	Get the corresponding topic. More...
Public Member Functions inherited from nt::Subscriber
virtual	~Subscriber ()
	Subscriber (const Subscriber &)=delete
Subscriber &	operator= (const Subscriber &)=delete
	Subscriber (Subscriber &&)
Subscriber &	operator= (Subscriber &&)
	operator bool () const
	Determines if the native handle is valid. More...
NT_Subscriber	GetHandle () const
	Gets the native handle for the subscriber. More...
bool	Exists () const
	Determines if the topic is currently being published. More...
int64_t	GetLastChange () const
	Gets the last time the value was changed. More...
Topic	GetTopic () const
	Gets the subscribed-to topic. More...

Additional Inherited Members
Protected Member Functions inherited from nt::Subscriber
	Subscriber ()=default
	Subscriber (NT_Subscriber handle)
Protected Attributes inherited from nt::Subscriber
NT_Subscriber	m_subHandle {0}

Detailed Description

NetworkTables Double subscriber.

Member Typedef Documentation

ParamType

using nt::DoubleSubscriber::ParamType = double

TimestampedValueType

using nt::DoubleSubscriber::TimestampedValueType = TimestampedDouble

TopicType

using nt::DoubleSubscriber::TopicType = DoubleTopic

ValueType

using nt::DoubleSubscriber::ValueType = double

Constructor & Destructor Documentation

DoubleSubscriber() [1/2]

nt::DoubleSubscriber::DoubleSubscriber ( )

default

DoubleSubscriber() [2/2]

nt::DoubleSubscriber::DoubleSubscriber ( NT_Subscriber  handle, ParamType  defaultValue  )

inline

Construct from a subscriber handle; recommended to use DoubleTopic::Subscribe() instead.

Parameters

handle	Native handle
defaultValue	Default value

Member Function Documentation

Get() [1/2]

double nt::DoubleSubscriber::Get ( ) const

inline

Get the last published value.

If no value has been published, returns the stored default value.

Returns

value

Get() [2/2]

double nt::DoubleSubscriber::Get ( ParamType  defaultValue ) const

inline

Get the last published value.

If no value has been published, returns the passed defaultValue.

Parameters

defaultValue

default value to return if no value has been published

Returns

value

GetAtomic() [1/2]

TimestampedDouble nt::DoubleSubscriber::GetAtomic ( ) const

inline

Get the last published value along with its timestamp If no value has been published, returns the stored default value and a timestamp of 0.

Returns

timestamped value

GetAtomic() [2/2]

TimestampedDouble nt::DoubleSubscriber::GetAtomic ( ParamType  defaultValue ) const

inline

Get the last published value along with its timestamp.

If no value has been published, returns the passed defaultValue and a timestamp of 0.

Parameters

defaultValue

default value to return if no value has been published

Returns

timestamped value

GetTopic()

DoubleTopic nt::DoubleSubscriber::GetTopic ( ) const

inline

Get the corresponding topic.

Returns

Topic

ReadQueue()

std::vector< TimestampedDouble > nt::DoubleSubscriber::ReadQueue ( )

inline

Get an array of all value changes since the last call to ReadQueue.

Also provides a timestamp for each value.

Note

The "poll storage" subscribe option can be used to set the queue depth.

Returns

Array of timestamped values; empty array if no new changes have been published since the previous call.

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

• networktables/DoubleTopic.h
• networktables/DoubleTopic.inc