Counting at the speed of light!
range() function.The range() function allows you to print a sequence of numbers with a given step size (default = 1). Notice that the list stops before the 2nd argument.
range(start,stop,step)
# Range function with a the default step-size of 1
for value in range(1,5):
print(value)
1
2
3
4
You can define a specific step-size to create more interesting sequences of numbers.
# Print all even numbers from 1-10
for value in range(1,11,2):
print(value)
1
3
5
7
9
You can also make a range of numbers into a list by calling the list() function. You can then use any of the list methods such as sort() to manipulate your list.
# Make a list of numbers from 1-4
numbers = list(range(1,5))
print(numbers)
[1, 2, 3, 4]
You are not just limited to counting by an integer step-size. You can specify an expression to generate almost any sequences imaginable:
# Create an empty list
squares = []
# For loop to generate integers from 1 to 10
for value in range(1,11):
# Append the square of the integer in value to the List
squares.append(value**2)
# Print the list
print(squares)
[1, 4, 9, 16, 25, 36, 49, 64, 81, 100]
You can use the min(), max() and sum() functions to get the minimum, maximum and sum of all the numbers in a list respectively
digits = [1,2,3,4,5,6,7,8,9,0]
# Find minimum, maximum and total sum of the digits list
print(min(digits))
print(max(digits))
print(sum(digits))
0
9
45
The program used to create the sequence of perfect square numbers in previous slide in three lines but with a list comprehension you can do all three steps in one line.
# Build a list of the first 10 perfect square numbers
squares = [value**2 for value in range(1,11)]
print(squares)
[1, 4, 9, 16, 25, 36, 49, 64, 81, 100]