[Fix] Fix mask order in sequence (#310)

Author: massquantity

libreco/batch/sequence.py

@@ -57,7 +57,7 @@ def get_interacted_seq(
             # first item has no historical interaction, fill in with pad_index
             batch_interacted_len.append(1.0)
         elif position < num:
-            batch_interacted[j, -position:] = consumed_items[:position]
+            batch_interacted[j, :position] = consumed_items[:position]
             batch_interacted_len.append(float(position))
         else:
             if mode == "recent":
@@ -79,7 +79,7 @@ def get_recent_seqs(n_users, user_consumed, pad_index, max_seq_len, dtype):
         u_consumed_items = user_consumed[u]
         u_items_len = len(u_consumed_items)
         if u_items_len < max_seq_len:
-            recent_seqs[u, -u_items_len:] = u_consumed_items
+            recent_seqs[u, :u_items_len] = u_consumed_items
             recent_seq_lens.append(float(u_items_len))
         else:
             recent_seqs[u] = u_consumed_items[-max_seq_len:]

libreco/recommendation/preprocess.py

@@ -38,7 +38,7 @@ def process_embed_seq(model, user_id, seq, inner_id):
 def build_rec_seq(seq, model, inner_id, repeat=False):
     seq, seq_len = _extract_seq(seq, model, inner_id)
     recent_seq = np.full((1, model.max_seq_len), model.n_items, dtype=np.int32)
-    recent_seq[0, -seq_len:] = seq[-seq_len:]
+    recent_seq[0, :seq_len] = seq[-seq_len:]
     seq_len = np.array([seq_len], dtype=np.float32)
     if repeat:
         recent_seq = np.repeat(recent_seq, model.n_items, axis=0)

libreco/utils/constants.py

@@ -84,6 +84,7 @@ class SageModels(StrEnum):
 @unique
 class UserEmbedModels(StrEnum):
     """Models can only generate user embeddings dynamically."""
+
     YOUTUBERETRIEVAL = "YouTubeRetrieval"
     RNN4REC = "RNN4Rec"
     CASER = "Caser"