For instance methods, I check that it is callable and not a class method. One caveat: this approach of using vars (or __dict__ for that matter) won't work with __slots__. Using Python 3.6.9 (because it's what the Docker image I'm using as my interpreter has):

How Python Figures Out Missing Parameters: When slicing, if you leave out any parameter, Python tries to figure it out automatically. If you check the source code of CPython, you will find a function called PySlice_GetIndicesEx() which figures out indices to a slice for any given parameters. Here is the logical equivalent code in Python.

Python's array module. The standard library also has the array module, which is a wrapper over C arrays. Like C arrays, array.array objects hold only a single type (which has to be specified at object creation time by using a type code), whereas Python list objects can hold anything.

Oct 3, 2009 · @AndersonGreen As I said there's no such thing as a variable declaration in Python. You would create a multidimensional list by taking an empty list and putting other lists inside it or, if the dimensions of the list are known at write-time, you could just write it as a literal like this: my_2x2_list = [[a, b], [c, d]].

Apr 18, 2011 · My solution was to create a class that returns an empty value, then subclass it and implement different value methods, then instantiate each subclass into an array, then call the instance's method depending on the row number. Global namespace polution is limited by making the subclasses inner to the table generator class.

No. NumPy arrays have, but standard python lists don't. Even so, the numpy array implementations are not what you'd expect: they don't take a predicate, but evaluate every element by converting them to boolean. Edit: any and all exist as functions (not as methods), but they don't apply predicates, but consider booleanized values as numpy methods.

@BT: I suspect at least part of the reason for __len__ vs. .length() is that all names that begin and end with double-underscores (dunders) are: 1) Reserved for language use, and 2) Allow the language to bypass normal lookup rules (e.g. the method can be looked up directly on the instance's class w/o checking if the instance has shadowed it with an attribute of the same name).

Jun 21, 2022 · For storage purposes, both numpy array and array.array are comparable. Here is the code for benchmark for both comparing storage size of unsigned integer of 4 bytes. Other datatypes can also be used for comparison.

Oct 31, 2008 · For example, if the list is an attribute of an object, self.l1 += l2 and self.l1.extend(l2) have identical performance on my Python 3.6 install, simply because real operation is more like self.l1 = self.l1.__iadd__(l2), which means it must perform a moderately expensive STORE_ATTR that self.l1.extend(l2) doesn't have to.

Mar 18, 2015 · For example, np.resize returns a new array with the specified shape. On the other hand, ndarray.resize changes the shape of the array in-place. The fill values used in each case are also different. Similarly, a.sort() sorts the array a …