A trigger specifies a timespot or several timespots during training, and a corresponding action will be taken when the timespot(s) s reached.

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Every Epoch

Scala:

 val trigger = Trigger.everyEpoch

Python:

 trigger = EveryEpoch()

A trigger that triggers an action when each epoch finishs. Could be used as trigger in setValidation and setCheckpoint in Optimizer, and also in TrainSummary.setSummaryTrigger.

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Several Iteration

Scala:

 val trigger = Trigger.severalIteration(n)

Python:

 trigger = SeveralIteration(n)

A trigger that triggers an action every n iterations. Could be used as trigger in setValidation and setCheckpoint in Optimizer, and also in TrainSummary.setSummaryTrigger.

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Max Epoch

Scala:

 val trigger = Trigger.maxEpoch(max)

Python:

 trigger = MaxEpoch(max)

A trigger that triggers an action when training reaches the number of epochs specified by "max". Usually used in Optimizer.setEndWhen.

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Max Iteration

Scala:

 val trigger = Trigger.maxIteration(max)

Python:

 trigger = MaxIteration(max)

A trigger that triggers an action when training reaches the number of iterations specified by "max". Usually used in Optimizer.setEndWhen.