Source code for pytorch_lightning.metrics.regression.mean_squared_log_error
# Copyright The PyTorch Lightning team.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
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# http://www.apache.org/licenses/LICENSE-2.0
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# Unless required by applicable law or agreed to in writing, software
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import torch
from typing import Any, Callable, Optional
from pytorch_lightning.metrics.metric import Metric
from pytorch_lightning.metrics.functional.mean_squared_log_error import (
_mean_squared_log_error_update,
_mean_squared_log_error_compute
)
[docs]class MeanSquaredLogError(Metric):
r"""
Computes `mean squared logarithmic error
<https://scikit-learn.org/stable/modules/model_evaluation.html#mean-squared-log-error>`_
(MSLE):
.. math:: \text{MSLE} = \frac{1}{N}\sum_i^N (\log_e(1 + y_i) - \log_e(1 + \hat{y_i}))^2
Where :math:`y` is a tensor of target values, and :math:`\hat{y}` is a tensor of predictions.
Args:
compute_on_step:
Forward only calls ``update()`` and return None if this is set to False. default: True
dist_sync_on_step:
Synchronize metric state across processes at each ``forward()``
before returning the value at the step. default: False
process_group:
Specify the process group on which synchronization is called. default: None (which selects the entire world)
Example:
>>> from pytorch_lightning.metrics import MeanSquaredLogError
>>> target = torch.tensor([2.5, 5, 4, 8])
>>> preds = torch.tensor([3, 5, 2.5, 7])
>>> mean_squared_log_error = MeanSquaredLogError()
>>> mean_squared_log_error(preds, target)
tensor(0.0397)
"""
def __init__(
self,
compute_on_step: bool = True,
dist_sync_on_step: bool = False,
process_group: Optional[Any] = None,
dist_sync_fn: Callable = None,
):
super().__init__(
compute_on_step=compute_on_step,
dist_sync_on_step=dist_sync_on_step,
process_group=process_group,
dist_sync_fn=dist_sync_fn,
)
self.add_state("sum_squared_log_error", default=torch.tensor(0.0), dist_reduce_fx="sum")
self.add_state("total", default=torch.tensor(0), dist_reduce_fx="sum")
[docs] def update(self, preds: torch.Tensor, target: torch.Tensor):
"""
Update state with predictions and targets.
Args:
preds: Predictions from model
target: Ground truth values
"""
sum_squared_log_error, n_obs = _mean_squared_log_error_update(preds, target)
self.sum_squared_log_error += sum_squared_log_error
self.total += n_obs
[docs] def compute(self):
"""
Compute mean squared logarithmic error over state.
"""
return _mean_squared_log_error_compute(self.sum_squared_log_error, self.total)