Class Neuron
java.lang.Object
org.apache.commons.math3.ml.neuralnet.Neuron
- All Implemented Interfaces:
Serializable
Describes a neuron element of a neural network.
This class aims to be thread-safe.
- Since:
- 3.3
- See Also:
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Method Summary
Modifier and TypeMethodDescriptionboolean
compareAndSetFeatures
(double[] expect, double[] update) Tries to atomically update the neuron's features.copy()
Performs a deep copy of this instance.double[]
Gets the neuron's features.long
Gets the neuron's identifier.long
Retrieves the number of calls to thecompareAndSetFeatures
method.long
Retrieves the number of successful calls to thecompareAndSetFeatures
method.int
getSize()
Gets the length of the feature set.
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Method Details
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copy
Performs a deep copy of this instance. Upon return, the copied and original instances will be independent: Updating one will not affect the other.- Returns:
- a new instance with the same state as this instance.
- Since:
- 3.6
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getIdentifier
public long getIdentifier()Gets the neuron's identifier.- Returns:
- the identifier.
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getSize
public int getSize()Gets the length of the feature set.- Returns:
- the number of features.
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getFeatures
public double[] getFeatures()Gets the neuron's features.- Returns:
- a copy of the neuron's features.
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compareAndSetFeatures
public boolean compareAndSetFeatures(double[] expect, double[] update) Tries to atomically update the neuron's features. Update will be performed only if the expected values match the current values.
In effect, when concurrent threads call this method, the state could be modified by one, so that it does not correspond to the the state assumed by another. Typically, a callerretrieves the current state
, and uses it to compute the new state. During this computation, another thread might have done the same thing, and updated the state: If the current thread were to proceed with its own update, it would overwrite the new state (which might already have been used by yet other threads). To prevent this, the method does not perform the update when a concurrent modification has been detected, and returnsfalse
. When this happens, the caller should fetch the new current state, redo its computation, and call this method again.- Parameters:
expect
- Current values of the features, as assumed by the caller. Update will never succeed if the contents of this array does not match the values returned bygetFeatures()
.update
- Features's new values.- Returns:
true
if the update was successful,false
otherwise.- Throws:
DimensionMismatchException
- if the length ofupdate
is not the same as specified in theconstructor
.
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getNumberOfAttemptedUpdates
public long getNumberOfAttemptedUpdates()Retrieves the number of calls to thecompareAndSetFeatures
method. Note that if the caller wants to use this method in combination withgetNumberOfSuccessfulUpdates()
, additional synchronization may be required to ensure consistency.- Returns:
- the number of update attempts.
- Since:
- 3.6
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getNumberOfSuccessfulUpdates
public long getNumberOfSuccessfulUpdates()Retrieves the number of successful calls to thecompareAndSetFeatures
method. Note that if the caller wants to use this method in combination withgetNumberOfAttemptedUpdates()
, additional synchronization may be required to ensure consistency.- Returns:
- the number of successful updates.
- Since:
- 3.6
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