python - What is the best way to get the number of elements in a PyTables row iterator? -


my current approach is:

rowiter = atable.where(condition) rowiter_length = max([i i, row in enumerate(rowiter)])

is there way length of rowiter without looping through entire iterator?

not sure if there's more efficient way, should using len(rowiter) instead of list comp, 2 reasons:

  1. if iterator object have more efficient way of calculating length, it'll have made accessible via __len__ special method, you'll speedup if it's available.
  2. enumerate starts @ index 0, construct return 1 less actual length of iterator.

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