Input: Output: What’s the most elegant (read: Pythonic) way to write intersperse? Answer I would have written a generator myself, but like this:
Tag: list
Slicing a list in Python without generating a copy
I have the following problem. Given a list of integers L, I need to generate all of the sublists L[k:] for k in [0, len(L) – 1], without generating copies. How do I accomplish this in Python? With a buffer object somehow? Answer The short answer Slicing lists does not generate copies of the objects in the list; it just
Why doesn’t list have safe “get” method like dictionary?
Why doesn’t list have a safe “get” method like dictionary? Answer 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 value) without throwing an exception, while it is super trivial to avoid exceptions accessing
Convert [key1,val1,key2,val2] to a dict?
Let’s say I have a list a in Python whose entries conveniently map to a dictionary. Each even element represents the key to the dictionary, and the following odd element is the value for example, and I’d like to convert it to a dictionary b, where What is the syntactically cleanest way to accomplish this? Answer If a is large,
Python: Sum string lengths
Is there a more idiomatic way to sum string lengths in Python than by using a loop? I tried sum(), but it only works for integers: Answer I know this is an old question, but I can’t help noting that the Python error message tells you how to do this: So:
Pythonic way to split a list into first and rest in Python 2.x?
I think in Python 3 I’ll be able to do: which is exactly what I want, but I’m using 2.6. For now I’m doing: This is fine, but I was just wondering if there’s something more elegant. Answer Basically the same, except that it’s a oneliner. Tuple assigment rocks. This is a bit longer and less obvious, but generalized for
Get difference between two lists with Unique Entries
I have two lists in Python: Assuming the elements in each list are unique, I want to create a third list with items from the first list which are not in the second list: Are there any fast ways without cycles and checking? Answer To get elements which are in temp1 but not in temp2 (assuming uniqueness of the elements in
Check if multiple strings exist in another string
How can I check if any of the strings in an array exists in another string? For example: How can I replace the if a in s: line to get the appropriate result? Answer You can use any: Similarly to check if all the strings from the list are found, use all instead of any.
Find and replace string values in list [duplicate]
This question already has answers here: Apply function to each element of a list (4 answers) Closed 5 months ago. The community reviewed whether to reopen this question 5 months ago and left it closed: Original close reason(s) were not resolved I got this list: What I would like is to replace [br] with some fantastic value similar to <br
How slow is Python’s string concatenation vs. str.join?
As a result of the comments in my answer on this thread, I wanted to know what the speed difference is between the += operator and ”.join() So what is the speed comparison between the two? Answer From: Efficient String Concatenation Method 1: Method 4: Now I realise they are not strictly representative, and the 4th method appends to a