💡 Problem Formulation: Python dictionaries store data as key-value pairs. Sometimes, e.g., for the purpose of iteration or other operations, we may want to create a list out of just the keys from a dictionary. Let’s explore some methods to do this, using a simple dictionary as an example: Our goal is to create a … Read more
In Python, transforming the values from a dictionary into a list is a common operation, especially when you need to perform list-specific operations or simply require an ordered collection of dictionary values. Problem Formulation Suppose you have a dictionary: You want to create a list of the counts, resulting in: Let’s explore several methods to … Read more
💡 Problem Formulation: When dealing with a list of strings in Python, you might encounter a situation where you need to filter the list based on the presence or absence of certain substrings. Here is a succinct example: ✅ Given the list [‘cat’, ‘carpet’, ‘castle’, ‘dog’] and the substring ‘ca’, the challenge is to produce … Read more
💡 Problem Formulation: When working with lists in Python, a common task is to filter elements from one list based on the contents of another list. For example, given a list of numbers list1 = [1, 2, 3, 4, 5] and a list of filters filters = [2, 3], how can we get a result … Read more
When coding in Python, you might encounter a scenario where you need to filter a list using multiple conditions. The filter() function, combined with a lambda function, can accomplish this in a concise and readable way. 💡 Problem Formulation: Let’s say we have a list of integers, and we want to filter out numbers that … Read more
Problem Formulation Imagine a scenario where you have a list of strings and your goal is to filter out only those strings that end with a specific suffix. Here’s a minimal example with the desired input and output: Input: Output: Method 1: Using a Loop with endswith() Python’s endswith() string method can be used within … Read more
💡 Problem Formulation: When working with lists of strings in Python, a common task is to filter the list based on whether the strings start with a specific prefix. Suppose you have a list of names, and you want to retrieve only those that start with the letter “J”. Below are several methods to accomplish … Read more
Below, we explore several methods to filter out empty strings from a list in Python. 💡 Problem Formulation: Given a list of strings like my_list = [“apple”, “”, “banana”, “cherry”, “”], we want to produce a new list that contains only the non-empty strings: [“apple”, “banana”, “cherry”]. Method 1: Using a for-loop The most straightforward … Read more
💡 Problem Formulation: When working with a list of strings in Python, a common task is to filter the list based on specific patterns. Regular Expressions (regex) are a powerful way of defining these patterns, enabling complex matching criteria that can go well beyond simple substring checks. Let’s see how we can use regex to … Read more
💡Problem Formulation: In Python, a common task is to filter a list of strings based on some pattern which may include wildcards (also called asterisks or star * operators). A wildcard character can represent one or multiple characters, making it a powerful tool for string pattern matching. Let’s look at several methods to do so … Read more
When working with text in Python, a common task is to determine how often a specific character or set of characters occurs within a string. This can be useful in various applications such as data preprocessing, parsing, or simply assessing the content of a string. 💡 Problem Formulation: The task is to write a Python … Read more
💡 Problem Formulation: Before diving into the solutions, let’s clearly define the problem. We want to count the number of characters in a string. This includes letters, digits, punctuation, and all other special characters. We assume we are given a string s, and we need to find the total number of characters in s. If … Read more