# Copyright (c) 2020, Fabio Muratore, Honda Research Institute Europe GmbH, and
# Technical University of Darmstadt.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
# 3. Neither the name of Fabio Muratore, Honda Research Institute Europe GmbH,
# or Technical University of Darmstadt, nor the names of its contributors may
# be used to endorse or promote products derived from this software without
# specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL FABIO MURATORE, HONDA RESEARCH INSTITUTE EUROPE GMBH,
# OR TECHNICAL UNIVERSITY OF DARMSTADT BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
# OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
# IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
import numpy as np
from pyrado.environment_wrappers.base import EnvWrapperAct
from pyrado.spaces.box import BoxSpace
[docs]class ActNormWrapper(EnvWrapperAct):
"""Environment wrapper which normalizes the action space, such that all action values are in range [-1, 1]."""
def _process_act(self, act: np.ndarray) -> np.ndarray:
# Get the bounds of the inner action space
lb, ub = self.wrapped_env.act_space.bounds
# Denormalize action
act_denorm = lb + (act + 1) * (ub - lb) / 2
return act_denorm # can be out of action space, but this has to be checked by the environment
def _process_act_space(self, space: BoxSpace) -> BoxSpace:
if not isinstance(space, BoxSpace):
raise NotImplementedError("Only implemented ActNormWrapper._process_act_space() for BoxSpace!")
# Return space with same shape but bounds from -1 to 1
return BoxSpace(-np.ones(space.shape), np.ones(space.shape), labels=space.labels)