Caveats Linear time-complexity in list length An index call checks every element of the list in order, until it finds a match. If the list is long, and if there is no guarantee that the value will be near the …

Of course the question asks specifically about lists so the best solution is to use the try-except method, however the speed improvements (at least 20x here compared to try-except) offered by using the …

Python's list.index(x) throws an exception if the item doesn't exist. Is there a better way to do this that doesn't require handling exceptions?

May 6, 2011 · The "Index" that your link is talking about is the same as Get Item in the python.org wiki. You can see in the cpython source code that the index method is doing an O (n) search of the list.

74 Python's list type has an index () method that takes one parameter and returns the index of the first item in the list matching the parameter. For instance:

172 Ultimately it probably doesn't have a safe .get method because a dict is an associative collection (values are associated with names) where it is inefficient to check if a key is present (and return its …

Feb 6, 2009 · Is there any built-in methods that are part of lists that would give me the first and last index of some value, like: verts.IndexOf(12.345) verts.LastIndexOf(12.345)

Mar 19, 2019 · My class implements an iterator so I can do: for i in class(): But I want to be able to access the class by index as well: class()[1] How can I do that?

Jul 16, 2016 · index = 0 for item in self.items: if item.id == desired_id: return index index = index + 1 return -1 I used -1 to indicate the item wasn't found. What's a better way to do this, and why doesn't …

Here's the timeit comparison of all the answers with list of 1000 elements on Python 3.9.1 and Python 2.7.16. Answers are listed in the order of performance for both the Python versions.