class_docstr: Additive Ornstein-Uhlenbeck process.
  
  Used in https://arxiv.org/abs/1509.02971 for exploration.
  
  Args:
      mu (float): Mean of the OU process
      theta (float): Friction to pull towards the mean
      sigma (float or ndarray): Scale of noise
      start_with_mu (bool): Start the process without noise
code: def __init__(
      self,
      mu=0.0,
      theta=0.15,
      sigma=0.3,
      start_with_mu=False,
      logger=getLogger(__name__),
  ):
      self.mu = mu
      self.theta = theta
      self.sigma = sigma
      self.start_with_mu = start_with_mu
      self.logger = logger
      self.ou_state = None
  
file_path: pfrl/pfrl/explorers/additive_ou.py
imports: from logging import getLogger
  import numpy
  from pfrl import explorer
label_desc: Use image node_id 1 to create a new AdditiveOU object from inherited base classes: explorer with example: obj = AdditiveOU(mu, theta, sigma, start_with_mu, logger)