Update app.py

app.py

@@ -345,8 +345,9 @@ def choose(img, choice, calibrate_prompts, user_id, request: gr.Request):
         choice = 0
     
     row_mask = [p.split('/')[-1] in img for p in prevs_df['paths'].to_list()]
-    prevs_df.loc[row_mask, 'user:rating'][0][user_id] = choice
-    prevs_df.loc[row_mask, 'latest_user_to_rate'] = [user_id]
+    if len(prevs_df.loc[row_mask, 'user:rating'][0]) > 0:
+        prevs_df.loc[row_mask, 'user:rating'][0][user_id] = choice
+        prevs_df.loc[row_mask, 'latest_user_to_rate'] = [user_id]
     img, calibrate_prompts = next_image(calibrate_prompts, user_id)
     return img, calibrate_prompts