This little guy is often overlooked by newbies because they think it’s just a fancy way to write out numbers on a line (which it can do), but let me tell you, my friends, this function has some serious power and versatility that will blow your mind!
To start what does `range()` actually do? Well, in simple terms, it generates a sequence of numbers within a specified range. This function can take up to three arguments: start (default is 0), stop (exclusive), and step (default is 1). Let me break that down for you:
– `start`: this specifies the starting number of your sequence. If you don’t include it, the default value is 0. For example, if you want to generate a range from 5 to 10 (inclusive), you can use `range(5, 11)`.
– `stop`: this specifies the ending number of your sequence. If you don’t include it, the default value is infinity. For example, if you want to generate a range from 0 to 9, you can use `range(0, 10)`. Note that the stop value is not included in the final result!
– `step`: this specifies how many numbers should be skipped between each number in your sequence. If you don’t include it, the default value is 1 (which means every number will be included). For example, if you want to generate a range from 0 to 9 with a step of 2 (i.e., only even numbers), you can use `range(0, 11, 2)`.
Now that we’ve covered the basics, some cool applications for this function! Here are just a few examples:
– Looping through a list of items using a for loop and range()
# This script is used to loop through a list of items using a for loop and range() function.
# First, we define a list of numbers called "my_list".
my_list = [1, 2, 3, 4, 5]
# Next, we use the range() function to generate a sequence of numbers from 0 to the length of "my_list" - 1.
# The range() function takes in three arguments: start, stop, and step.
# In this case, we want to start at 0, stop at the length of "my_list" - 1, and increment by 1 each time.
# Note: The stop value is not included in the sequence, so we use the length of "my_list" - 1 to ensure we loop through all the items in the list.
for i in range(0, len(my_list), 1):
# Inside the for loop, we use the current value of "i" as the index to access each item in "my_list".
# We use the print() function to display the item at the current index.
print(my_list[i])
– Generating a list of numbers within a specified range using list() and range()
# Generating a list of numbers within a specified range using list() and range()
# Create a list of numbers from 0 to 9 using the range() function
numbers = list(range(10))
# Print the list of numbers
print(numbers)
# Output: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
# The range() function creates a sequence of numbers starting from 0 up to the specified number (10 in this case)
# The list() function then converts this sequence into a list and assigns it to the variable "numbers"
# The print() function then displays the list of numbers on the screen
– Reversing the order of a sequence using slice notation or reversed() function with range()
# Reversing the order of a sequence using slice notation or reversed() function with range()
# Creating a list with numbers 1 to 5
my_list = [1, 2, 3, 4, 5]
# Using slice notation to reverse the order of the list
# The range() function creates a sequence of numbers from 0 to the length of the list
# The [::-1] notation reverses the sequence, resulting in a reversed list
reversed_list = list(range(len(my_list))[::-1])
# Printing the reversed list
print(reversed_list)
# Using the reversed() function to reverse the order of the list
# The reversed() function takes in a sequence and returns a reversed iterator
# The list() function converts the iterator into a list
reversed_list = list(reversed(range(len(my_list))))
# Printing the reversed list
print(reversed_list)
– Generating a sequence of random numbers within a specified range using randint() and range() from Python’s `random` module
# Import the random module
import random
# Create a list of 5 random numbers between 1 and 6 using list comprehension
# The "_" is used as a placeholder for the index, as it is not needed in this case
numbers = [random.randint(1, 6) for _ in range(5)]
# Print the list of random numbers
print(numbers)
– Generating a sequence of numbers with negative step using range() and list()
# Generating a sequence of numbers with negative step using range() and list()
# Create a list using the range function with a negative step of 3
my_list = list(range(-10, -20, -3))
# Print the list
print(my_list)
# Output: [-10, -13, -16, -19]
# The range function creates a sequence of numbers starting from -10 and ending at -20 with a step of -3.
# The list function then converts this sequence into a list and assigns it to the variable my_list.
# Finally, the print function displays the contents of my_list.
As you can see, the `range()` function is incredibly versatile and can be used in a variety of ways to enhance your Python code. So next time you’re working on a project that involves loops or generating sequences of numbers, remember to give this little guy some love!