See the "NumLearningCycles" section on the page https://www.mathworks.com/help/stats/fitcensemble.html.
The info from there:
NumLearningCycles — Number of ensemble learning cycles
100 (default) | positive integer | 'AllPredictorCombinations'
Number of ensemble learning cycles, specified as the comma-separated pair consisting of 'NumLearningCycles' and a positive integer or 'AllPredictorCombinations'.
- If you specify a positive integer, then, at every learning cycle, the software trains one weak learner for every template object in Learners. Consequently, the software trains NumLearningCycles*numel(Learners) learners.
- If you specify 'AllPredictorCombinations', then set Method to 'Subspace' and specify one learner only for Learners. With these settings, the software trains learners for all possible combinations of predictors taken NPredToSample at a time. Consequently, the software trains nchoosek(size(X,2),NPredToSample) learners.
The software composes the ensemble using all trained learners and stores them in Mdl.Trained.
Example: 'NumLearningCycles',500
Data Types: single | double | char | string
