Problem: Given are two lists l1 and l2. You want to perform either of the following: 1. Boolean Comparison: Compare the lists element-wise and return True if your comparison metric returns True for all pairs of elements, and otherwise False. 2. Difference: Find the difference of elements in the first list but not in the …
The Most Pythonic Way to Compare Two Lists in Python Read More »
The standard way of checking if an element exists in a list is to use the in keyword. For example, ‘Alice’ in [1, ‘Alice’, 3] will return True while the same returns False for ‘Bob’. If you need to check more complicated conditions, use the any(condition(x) for x in list) function with a generator expression. …
The Most Pythonic Way to Check If a List Contains an Element Read More »
To convert a list lst of strings to a string, use the ”.join(lst) method with an empty separator string between the elements. If you have a list of objects, first convert each element to a string and join the result with the generator expression ”.join(str(x) for x in lst). Problem: Given a list of elements. …
The Most Pythonic Way to Convert a List to a String Read More »
If you’re like me, you may have asked yourself the following question: Why is it string.join(list) instead of list.join(string) in Python? 🙄 The join method works with any iterable, not just with lists. Therefore, you’d have to implement it in hundreds of classes instead of just one (in the string class). Additionally, join() works only …
string.join(list) vs list.join(string) | Why Python’s Creators Chose The Former Read More »
The most Pythonic way to concatenate a list of objects is the expression ”.join(str(x) for x in lst) that converts each object to a string using the built-in str(…) function in a generator expression. You can concatenate the resulting list of strings using the join() method on the empty string as a delimiter. The result …
How to Use Python’s Join() on a List of Objects (Not Strings)? Read More »
To join specific list elements (e.g., with indices 0, 2, and 4) and return the joined string that’s the concatenation of all those, use the expression ”.join([lst[i] for i in [0, 2, 4]]). The list comprehension statement creates a list consisting of elements lst[0], lst[2], and lst[4]. The ”.join() method concatenates those elements using the …
To join and replace all strings in a list lst between start index 1 and end index 5, use the one-liner lst[1:5] = [”.join(lst[1:5])]. This solution is based on slice assignment that selects the slice you want to replace on the left and the values to replace it on the right side of the assignment. …
Given a list of strings. Join the first with the second string, the second with the third, and so on. The one-liner [lst[i] + lst[i+1] for i in range(0, len(lst), 2)] solves the problem by using the range function to iterate over every other index i=0, 2, 4, 5, … to concatenate the i-th and …
If the search phrase “Python Join List Range” brought you here, you’re having most likely one of the following problems: You don’t know how to concatenate two range() iterables, or You want to use .join() to create a string from a range() iterable—but it doesn’t work. In any case, by reading this article, I hope …
The most efficient method to join a list of Python strings in reverse order is to use the Python code ”.join(l[::-1]). First, reverse the list l using slicing with a negative step size l[::-1]. Second, glue together the strings in the list using the join(…) method on the empty string ”. Problem: Given a list …
The Most Pythonic Way to Join a List in Reverse Order Read More »
When teaching the Finxter Python students, I’m often shocked how even intermediate-level coders do not understand the very basic foundations of computer science. In CS, there’s almost nothing as fundamental as a simple, plain byte. (You know, that sequence of 0s and 1s called bits). This tutorial aims to clarify some misconceptions and questions regarding …
Python Join List of Bytes (and What’s a Python Byte Anyway?) Read More »