Class StackingSensor

Sensor that wraps around another Sensor to provide temporal stacking. Conceptually, consecutive observations are stored left-to-right, which is how they're output For example, 4 stacked sets of observations would be output like | t = now - 3 | t = now -3 | t = now - 2 | t = now | Internally, a circular buffer of arrays is used. The m_CurrentIndex represents the most recent observation.

Currently, compressed and multidimensional observations are not supported.

Inheritance
Object
StackingSensor
Namespace: Unity.MLAgents.Sensors
Syntax
public class StackingSensor : object, ISensor

Constructors

StackingSensor(ISensor, Int32)

Initializes the sensor.

Declaration
public StackingSensor(ISensor wrapped, int numStackedObservations)
Parameters
Type Name Description
ISensor wrapped

The wrapped sensor.
Int32 numStackedObservations

Number of stacked observations to keep.

Methods

GetCompressedObservation()

Return a compressed representation of the observation. For small observations, this should generally not be implemented. However, compressing large observations (such as visual results) can significantly improve model training time.

Declaration
public virtual byte[] GetCompressedObservation()
Returns
Type Description
Byte[]

Compressed observation.
Implements

GetCompressionType()

Return the compression type being used. If no compression is used, return None.

Declaration
public virtual SensorCompressionType GetCompressionType()
Returns
Type Description
SensorCompressionType

Compression type used by the sensor.
Implements

GetName()

Get the name of the sensor. This is used to ensure deterministic sorting of the sensors on an Agent, so the naming must be consistent across all sensors and agents.

Declaration
public string GetName()
Returns
Type Description
String

The name of the sensor.
Implements

GetObservationShape()

Returns the size of the observations that will be generated. For example, a sensor that observes the velocity of a rigid body (in 3D) would return new {3}. A sensor that returns an RGB image would return new [] {Height, Width, 3}

Declaration
public int[] GetObservationShape()
Returns
Type Description
Int32[]

Size of the observations that will be generated.
Implements

Reset()

Resets the internal states of the sensor. This is called at the end of an Agent's episode. Most implementations can leave this empty.

Declaration
public void Reset()
Implements

Update()

Updates the index of the "current" buffer.

Declaration
public void Update()
Implements

Write(ObservationWriter)

Write the observation data directly to the ObservationWriter. Note that this (and GetCompressedObservation()) may be called multiple times per agent step, so should not mutate any internal state.

Declaration
public int Write(ObservationWriter writer)
Parameters
Type Name Description
ObservationWriter writer

Where the observations will be written to.
Returns
Type Description
Int32

The number of elements written.
Implements