Design Review 1: KLIFF Trainer framework

kliff/_exceptions.py

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+"""
+This module contains exceptions to be raised in kliff modules, along with details on
+where they are raised.
+"""
+
+
+class TrainerError(Exception):
+    """
+    Exceptions to be raised in Trainer and associated classes.
+    """
+
+    def __init__(self, message):
+        super().__init__(message)

kliff/trainer/__init__.py

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+from .kim_trainer import KIMTrainer
+from .kliff_trainer import Trainer

kliff/trainer/kim_residuals.py

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+from typing import Any, Dict
+
+import numpy as np
+
+
+def MSE_residuals(
+    predictions: np.ndarray,
+    targets: np.ndarray,
+) -> np.ndarray:
+    r"""
+    Compute the mean squared error (MSE) of the residuals.
+
+    Args:
+
+    Returns:
+        The MSE of the residuals.
+    """
+    residuals = predictions - targets
+    return np.mean(residuals**2)