# -*- coding: utf-8 -*-
# (C) Copyright 2020, 2021, 2022 IBM. All Rights Reserved.
#
# This code is licensed under the Apache License, Version 2.0. You may
# obtain a copy of this license in the LICENSE.txt file in the root directory
# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.
#
# Any modifications or derivative works of this code must retain this
# copyright notice, and modified files need to carry a notice indicating
# that they have been altered from the originals.
"""Global drift compensation for inference."""
from torch.autograd import no_grad
from torch import abs as torch_abs
from torch import clamp, Tensor, eye
from aihwkit.inference.compensation.base import BaseDriftCompensation
[docs]class GlobalDriftCompensation(BaseDriftCompensation):
"""Global drift compensation.
Uses a constant factor for compensating the drift.
"""
[docs] @no_grad()
def readout(self, out_tensor: Tensor) -> Tensor:
"""Read outs the mean abs."""
return clamp(torch_abs(out_tensor).mean(), min=0.0001)
[docs] @no_grad()
def get_readout_tensor(self, in_size: int) -> Tensor:
"""Return the read-out tensor.
Uses the set of one-hot vectors (eye).
"""
return eye(in_size)
def __str__(self) -> str:
return '{}()'.format(self.__class__.__name__)