NumPy's arrays are more compact than Python lists -- a list of lists as you describe, in Python, would take at least 20 MB or so, while a NumPy 3D array with single-precision floats in the …

177 The += operator in python seems to be operating unexpectedly on lists. Can anyone tell me what is going on here?

In Python, when should you use lists and when tuples? Sometimes you don't have a choice, for example if you have "hello %s you are %s years old" % x then x must be a tuple. But if I am …

Python creating a dictionary of lists Asked 16 years, 7 months ago Modified 2 years, 10 months ago Viewed 637k times

Mar 19, 2019 · One common application for this technique is to avoid deeply nested loops. See Avoiding nested for loops for a more specific duplicate. Similarly, this technique might be used …

Python's own built-in deepcopy is based around that example. The only difference is it supports other types, and also supports user-classes by duplicating the attributes into a new duplicate …

The colon, :, is what tells Python you're giving it a slice and not a regular index. That's why the idiomatic way of making a shallow copy of lists in Python 2 is

30 The difference between two lists (say list1 and list2) can be found using the following simple function.

Oct 31, 2008 · 1) The difference between append and extend append: Appends any Python object as-is to the end of the list (i.e. as a the last element in the list). The resulting list may be …

405 How do I concatenate two lists in Python? As of 3.9, these are the most popular stdlib methods for concatenating two (or more) lists in Python. ... * A solution will qualify as a …