Is there a quick and easy way to get the first character from a string in Python? Yes, there is using the slice operator. To get the first character in a string simply use the code my_string[0] where my_string is a variable containing the string and the slice operator [0] captures the first index of that string, being the first character. ...
How do you get the last character from a string using Python? Thankfully Python has an easy way to fetch the last character from a string using the slice operator. To get the last character of the string in Python use the syntax my_string[-1]. The square brackets are used to indicate a specific character by index number, and as string data types can be iterated, you can use the slice operator [:], specifically -1 inside to capture the last character. ...
Creating a list in Python can be super easy, but how do you populate that list with a bunch on zeroes? To create a list of zeroes in Python use the syntax [0] * n where n represents the number of items needed to create the list of zeroes required. Here’s an example demonstrating this use: 1 2 3 >>> my_zeros_list = [0] * 5 >>> print(my_zeros_list) [0, 0, 0, 0, 0] As you can see from the above example the list containing five elements are all populated with the value of 0. ...
How can you remove the first and last characters from a string easily in Python? Can it be done using just one line of code? To remove the first and last characters from a string in Python use the slice operator on the string to return the needed characters, for example, my_string[1:-1]. Here is an example demonstrating the technique: 1 2 3 >>> my_string = "<html>" >>> my_string[1:-1] 'html' Slice Notation: How Does It Work? The powerful slice operator in Python allows you to capture a range according to the following pattern: ...
How do you know if an element in Python is empty? First, you need to define what is meant by the term empty. Does it mean None or an empty string "" or something else? For the examples in this article, I’ll assume that empty means an element is defined as None, however, if you’ve defined empty as something else then you can simply substitute my None references to your definition of an empty element. ...
To insert or append an empty element into a Python list you need to first define what is meant by the word empty. By empty do you mean an empty string, None or something else? While I may use None in this post you can easily substitute it for something else according to your requirements. To add an empty element into a list either replace the existing element with the empty variable or if inserting it at the end use the list method .append() or if inserting it at a specific place use the other list method .insert(). ...
Similar to the previous post on how to check if a string is empty the same principles and methods apply when checking if a list is empty in Python. To check if a list is empty either use the direct approach by using an expression where a list is compared to an empty list or use the boolean expression with a not operator (i.e. if not my_empty_list:) or use the built-in function len() to see if the length of the list is 0. ...
How can you check if a string is empty in Python? To determine if a string is empty in Python use of the following three means available: see if the string has any length by using the built-in len() function, do a direct comparison using the expression == "" or convert the string to a boolean data type and if the result is false it is an empty string. Let’s look at each approach and see how they perform. ...
A way to easily sort a list of strings equally is to change all the strings to lower case, but how do you change strings to lower case in Python? To change a string to lower case in Python use the string method .lower() like this: my_string.lower(). Similarly, to change a string to upper case in Python use the string method .upper() like this: my_string.upper(). An example of how this works is as follows: ...
It can be easy to sort a list, whether a list of strings or even a list of dictionaries, but can you sort a dictionary? One way to sort a dictionary by the values of each key : value pair in Python is to use a dictionary comprehension. Dictionary comprehensions are very similar to list comprehensions and have the following schema: 1 new_dict = { key: value for (key, value) in original_dict.items()} The first expression within the dictionary comprehension, the key: value portion, is the basic structure for setting any key and value pair within a dictionary. The second expression is familiar as the one-liner for loop, and within this statement we have a tuple representing the key and value returned from the dictionary’s .items() method. ...