How to calculate Top-5 accuracy?

[penghusile]

If I change
_, preds_index = preds.topk(1, dim=-1, largest=True, sorted=True)
to
_, preds_index = preds.topk(k=5, dim=-1, largest=True, sorted=True),
the program raise error

dataset_root:    data_lmdb_release/evaluation/CUTE80     dataset: /
sub-directory:  /.       num samples: 288
Traceback (most recent call last):
  File "test.py", line 318, in <module>
    test(opt)
  File "test.py", line 271, in test
    benchmark_all_eval(model, criterion, converter, opt)
  File "test.py", line 57, in benchmark_all_eval
    _, accuracy_by_best_model, norm_ED_by_best_model, _, _, _, infer_time, length_of_data = validation(
  File "test.py", line 151, in validation
    preds_str = converter.decode(preds_index[:,1], length_for_pred)
  File "/home/WeiHongxi/PengHusile/Server/ViTSTR/utils.py", line 197, in decode
    text = ''.join([self.character[i] for i in text_index[index, :]])
IndexError: too many indices for tensor of dimension 1```

or the accuracy turn to 0%