Find the minimum and maximum of a list in Python

min() gives the smallest item in a list and max() gives the largest. Writing the same thing with a loop shows how they work.

The program

temperatures = [21.5, 18.0, 25.3, 19.8, 23.1]

print("Lowest:", min(temperatures))
print("Highest:", max(temperatures))
print("Hottest day is number", temperatures.index(max(temperatures)) + 1)

Lowest: 18.0
Highest: 25.3
Hottest day is number 3

How it works

• min() and max() look at every item once and return the smallest or largest value.
• temperatures.index(value) gives the position of the first item equal to value. Positions start at 0, so we add 1 to get "day 3".
• Both functions also work on strings, where "smallest" means first in alphabetical order: min(["Linus", "Ada", "Grace"]) is "Ada".

Another way: by hand

Start with the first item as both the smallest and the largest so far, then compare every other item with them:

numbers = [3, 1, 4, 1, 5, 9, 2, 6]

smallest = numbers[0]
largest = numbers[0]
for n in numbers[1:]:
    if n < smallest:
        smallest = n
    if n > largest:
        largest = n

print("Min:", smallest)
print("Max:", largest)

Min: 1
Max: 9

An empty list

min([]) raises a ValueError, because there is no smallest item. Give a default value to get that value instead:

print(min([], default=None))
print(max([], default=0))

None
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