![]() But since it is wrapped in a reversed() function call, the elements are printed in reverse order. In the example above, range() has a default start of 0 and a stop of 5, so it goes from 0 to 4. ![]() You may have seen this coming, but you can combine the range() and reversed() functions to reverse a range in Python. Reversing a Range Using range() and reversed() Print(my_reversed_object) # not very useful! Note that, just like with the range() function, you need to iterate over reversed objects – or use the list() or tuple() functions – to actually get their values: Here’s how it looks:Īs you can see, the elements in my_list were printed in reverse order. The reversed() function is used to… well, reverse a sequence! You simply provide any sequence to reversed() and it will store its elements in the reverse order. But what if you need these values in the reverse order? The reversed() Function R3 = range(4, 10, 2) # start = 4, stop = 10, step = 2Īs you can see, there are ways to define virtually any range of numbers you may want. ![]() # start = 2, stop = 6, step = 1 (default) # start = 0 (default), stop = 3, step = 1 (default) Here are some examples of the start, stop, and step parameters in action: To provide a step argument, you need to provide the start and stop as well. ![]() If you pass two arguments to the range function, they are interpreted as the start and the stop (in this specific order). A step value of 3 means that the range includes one element for every 3 numbers (e.g. Its default value is 1, meaning that no values are skipped. The step represents the number of elements to “skip” at every iteration.A range with a stop of 7 will have the number 6 as its last element. Note that the range goes up to the stop value, but does not include it. The stop represents the end point of the range.The start represents the initial value in the range.Until now, we’ve simply passed a single number to range(), but this function actually accepts up to three arguments: start, stop, and step. Parameters of the Python range() Function The range() function can be used in for loops simply as a way to perform an action repeatedly:įor n in range(10): # repeat the code below 10 times Sometimes, you may not care about the numbers in the range. In the example above, we passed 5 to the range() function, so the last number printed was 4 (since 5 - 1 = 4). For example, provided a number n, range() produces integers from 0 up to n-1. If the name “for loop” confuses you, we recommend checking out our Learn Programming with Python track, which goes over - and well beyond - all of Python’s basic syntax.īelow is a simple example of using the range() function in a for loop:ĭespite the simplicity of these examples, we can already detect some properties of the range() function. You can use the list() or tuple() functions for this (and you can learn more about lists and tuples in this article):Īnother way to access the numbers in the range is to iterate over it in a for loop. So to access the numbers, you’ll need to turn the range into a sequence. This may not sound very exciting at first, but range() is useful in many contexts - some of which we will explore later in this article.īut wait, where are the numbers? A range object doesn’t actually show its elements to you until you explicitly request them. Let’s start with the basics: Python’s range() function is used to produce a sequence of increasing numbers (or decreasing numbers, as we will see below). Let’s get started! Basic Usage of the range() Function After finishing this article, be sure to check out our Built-in Algorithms in Python course, which includes lots of exercises for the functions you’ll see here. We will start by introducing the range() function and work our way through some examples. In this article, we will learn a few different options. As it turns out, there are multiple ways of reversing a range in Python.
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