smac.optimizer.smbo¶
Classes
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Interface that contains the main Bayesian optimization loop. |
- class smac.optimizer.smbo.SMBO(scenario, stats, initial_design, runhistory, runhistory2epm, intensifier, num_run, model, acq_optimizer, acquisition_func, rng, tae_runner, restore_incumbent=None, random_configuration_chooser=<smac.optimizer.configuration_chooser.random_chooser.ChooserNoCoolDown object>, predict_x_best=True, min_samples_model=1, epm_chooser=<class 'smac.optimizer.configuration_chooser.epm_chooser.EPMChooser'>, epm_chooser_kwargs=None)[source]¶
Bases:
object
Interface that contains the main Bayesian optimization loop.
- Parameters
scenario (smac.scenario.scenario.Scenario) – Scenario object
stats (Stats) – statistics object with configuration budgets
initial_design (InitialDesign) – initial sampling design
runhistory (RunHistory) – runhistory with all runs so far
runhistory2epm (AbstractRunHistory2EPM) – Object that implements the AbstractRunHistory2EPM to convert runhistory data into EPM data
intensifier (Intensifier) – intensification of new challengers against incumbent configuration (probably with some kind of racing on the instances)
num_run (int) – id of this run (used for pSMAC)
model (BaseEPM) – empirical performance model
acq_optimizer (AcquisitionFunctionMaximizer) – Optimizer of acquisition function.
acquisition_func (AcquisitionFunction) – Object that implements the AbstractAcquisitionFunction (i.e., infill criterion for acq_optimizer)
restore_incumbent (Configuration) – incumbent to be used from the start. ONLY used to restore states.
rng (np.random.RandomState) – Random number generator
tae_runner (smac.tae.base.BaseRunner Object) – target algorithm run executor
random_configuration_chooser (
RandomChooser
) – Chooser for random configuration – one of * ChooserNoCoolDown(modulus) * ChooserLinearCoolDown(start_modulus, modulus_increment, end_modulus)predict_x_best (bool) – Choose x_best for computing the acquisition function via the model instead of via the observations.
min_samples_model (int) – Minimum number of samples to build a model.
epm_chooser_kwargs (Optional[Dict]) – Additional arguments passed to epmchooser
- logger¶
- incumbent¶
- scenario¶
- config_space¶
- stats¶
- initial_design¶
- runhistory¶
- intensifier¶
- num_run¶
- rng¶
- initial_design_configs¶
- epm_chooser¶
- tae_runner¶
- run()[source]¶
Runs the Bayesian optimization loop.
- Returns
incumbent – The best found configuration.
- Return type
np.array(1, H)
- start()[source]¶
Starts the Bayesian Optimization loop.
Detects whether the optimization is restored from a previous state.
- Return type
None
- validate(config_mode='inc', instance_mode='train+test', repetitions=1, use_epm=False, n_jobs=- 1, backend='threading')[source]¶
Create validator-object and run validation, using scenario- information, runhistory from smbo and tae_runner from intensify.
- Parameters
config_mode (str or list<Configuration>) – string or directly a list of Configuration str from [def, inc, def+inc, wallclock_time, cpu_time, all] time evaluates at cpu- or wallclock-timesteps of: [max_time/2^0, max_time/2^1, max_time/2^3, …, default] with max_time being the highest recorded time
instance_mode (string) – what instances to use for validation, from [train, test, train+test]
repetitions (int) – number of repetitions in nondeterministic algorithms (in deterministic will be fixed to 1)
use_epm (bool) – whether to use an EPM instead of evaluating all runs with the TAE
n_jobs (int) – number of parallel processes used by joblib
- Returns
runhistory – runhistory containing all specified runs
- Return type