How do I declare an array in Python? - Stack Overflow
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]].
python - Check if item is in an array / list - Stack Overflow
I'm also going to assume that you mean "list" when you say "array." Sven Marnach's solution is good. If you are going to be doing repeated checks on the list, then it might be worth converting it to a set or frozenset, which can be faster for each check.
python - array.array versus numpy.array - Stack Overflow
Jun 21, 2022 · In defense of array.array, I think its important to note that it is also a lot more lightweight than numpy.array, and that saying 'will do just fine' for a 1D array should really be 'a lot faster, smaller, and works in pypy/cython without issues.'
python - Difference between array[i][:] and array[i ... - Stack Overflow
May 17, 2017 · x[:] makes a shallow copy of a list, but is virtually useless when x is an array. It makes a new view - same data and shape, but different array object.
Python list vs. array – when to use? - Stack Overflow
Aug 17, 2022 · array.array is also a reasonable way to represent a mutable string in Python 2.x (array('B', bytes)). However, Python 2.6+ and 3.x offer a mutable byte string as bytearray . However, if you want to do math on a homogeneous array of numeric data, then you're much better off using NumPy, which can automatically vectorize operations on complex ...
Meaning of list[-1] in Python - Stack Overflow
Sep 19, 2018 · So, if you wanted the last element in array, you would call array[-1]. All your return c.most_common()[-1] statement does is call c.most_common and return the last value in the resulting list, which would give you the least common item in that list.
What does [:-1] mean/do in python? - Stack Overflow
Mar 20, 2013 · Working on a python assignment and was curious as to what [:-1] means in the context of the following code: instructions = f.readline()[:-1] Have searched on here on S.O. and on Google but to no a...
How to create an integer array in Python? - Stack Overflow
Dec 7, 2009 · Use the array module. With it you can store collections of the same type efficiently. >>> import array >>> import itertools >>> a = array_of_signed_ints = array.array("i", itertools.repeat(0, 10)) For more information - e.g. different types, look at the documentation of the array module. For up to 1 million entries this should feel pretty snappy.
python - What does [:] mean? - Stack Overflow
Jul 16, 2019 · used for limiter or slicing in array , hash eg: [1:5] for displaying values between 1 inclusive and 5 exclusive i.e 1-4 [start:end] basically used in array for slicing , understand bracket accept variable that mean value or key to display, and " : …
Erase whole array Python - Stack Overflow
Aug 17, 2010 · Differences worth noting: you need to specify the type when creating the array, and you save storage at the expense of extra time converting between the C type and the Python type when you do arr[i] = expression or arr.append(expression), and lvalue = arr[i]