# The Range Function¶

You can use the range function to create a list of numbers. If the range function is passed just one value it will return a list of all the numbers from 0 to one less than that number.

csp-7-4-1: Which of the following lines actually gives us a list of all the numbers from 0 to 5?
• range(5)
• This will return a list of all the numbers from 0 to 4.
• range(6)
• This will return a list of all the numbers from 0 to 5.
• range(7)
• This will return a list of all the numbers from 0 to 6.

If two values are passed as input to the range function then it will return a list of values that includes the first value, but ends at one less than the second value. It is inclusive of the first value and exclusive of the second value.

csp-7-4-2: Which of the following lines actually gives us a list of all numbers from 1 to 10?
• range(10)
• That includes zero and doesn't include 10: [0,1,2,3,4,5,6,7,8,9]
• range(1,10)
• That doesn't include 10: [1,2,3,4,5,6,7,8,9]
• range(11)
• That includes zero: [0,1,2,3,4,5,6,7,8,9,10]
• range(1,11)
• That returns [1,2,3,4,5,6,7,8,9,10]

Let’s rewrite the program that calculates the product using the range function to generate the list of numbers as shown below.

csp-7-4-3: Change ONE number in the above program to tell us the product of all numbers from 1 to 20
• 121645100408832000
• That is the product of all numbers from 1 to 19 (e.g., you changed the 11 to 20)
• 3628800
• That is the product of all numbers from 1 to 10 (e.g., no change at all)
• 362880
• That is the product of all numbers from 1 to 9 (e.g., you changed the 11 to 10)
• 2432902008176640000
• That is the product of all numbers from 1 to 20 (e.g., you changed the 11 to 21)

Note

Discuss topics in this section with classmates.