public code v1

pygrex/explain/individual/explainer.py

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+from tqdm.auto import tqdm
+
+from abc import ABC, abstractmethod
+from typing import Dict, Any
+
+
+class Explainer(ABC):
+    def __init__(self, model, recommendations, data):
+        self.model = model
+        self.recommendations = recommendations
+        self.dataset = data.dataset
+        self.num_items = data.num_item
+        self.num_users = data.num_user
+        self.users = self.dataset.groupby(by="userId")
+
+    def explain_recommendations(self):
+        explanations = []
+
+        with tqdm(
+            total=self.recommendations.shape[0], desc="Computing explanations: "
+        ) as pbar:
+            for _, row in self.recommendations.iterrows():
+                explanations.append(
+                    self.explain_recommendation_to_user(
+                        int(row.userId), int(row.itemId)
+                    )
+                )
+                pbar.update()
+
+        self.recommendations["explanations"] = explanations
+        return self.recommendations
+
+    def get_user_items(self, user_id):
+        """
+        Items Ids rated by a user.
+        :param user_id: the user
+        :return: list
+        """
+        return self.users.get_group(user_id).itemId.values
+
+    @abstractmethod
+    def explain_recommendation_to_user(
+        self, user_id: int, item_id: int
+    ) -> Dict[str, Any]:
+        """
+        Generates an explanation for a single user-item recommendation.
+        This method must be implemented by any subclass.
+        """
+        raise NotImplementedError