Using Python to Find Maximum Value in List

To get the maximum of a list in Python, we can use the Python max() function. You can use the max() function in Python to get the maximum value of a list of numbers, strings and objects.

list_of_numbers = [10,32,98,38,47,34]

print(max(list_of_numbers))

#Output
98

When working with different collections of data in Python, the ability to be able to summarize and find properties of these pieces of data are valuable.

One such case is if you want to find the maximum value of a list in Python.

You can use the Python max() function to find the maximum, or biggest, value in a list made up of numbers or strings.

Let’s say we have the following list of numbers in Python. You can use the Python built-in max() function to get the maximum value of the list in the following way:

list_of_numbers = [10,32,98,38,47,34]

print(max(list_of_numbers))

#Output
98

For a collection of strings, the biggestvalue is determaxed after sorting alphabetically.

print(max("Mike","Alex","Patricia"))

#Output
Patricia

Using Lambda Expression with max() Function on List of Objects in Python

Depending on the objects in your list, it might make sense that you need to apply a function or want to find the maximum value based on a certain attribute of the objects in a list.

One cool thing is that you can pass a lambda expression to the “key” parameter to instruct max() what to use to find the maximum value.

One use of a lambda expression with max() is if you want to find the maximum value in list of objects.

For example, if we have a list of numbers and want to take the maximum after applying the absolute value to each element, we can use a lambda.

Below shows a simple example of using a lambda expression with max() in Python.

example_list = [0, 3, 1, -3, -5, 4]

print(max(example_list, key=lambda x:abs(x)))

#Output:
5

Another example is let’s say we have a list of dictionaries and want to find the maximum value over our list for the key “height”.

You can easily do this with “key” and a lambda expression.

Below is an example of how to use a lambda expression with max() to get the maximum value of a list of dictionaries for a given key.

data = [{"name":"Andrew", "age":10, "height":50}, {"name":"Sally", "age":9, "height":45}, {"name":"Jose", "age":11, "height":52}]

print(max(data,key=lambda x: x["height"]))

#Output:
{"name":"Jose", "age":11, "height":52}

If you have a list of tuples, you can use “key” and a lambda as well to get the maximum value of a given position in the tuples.

Below is an example of how to use a lambda expression with max() to get the maximum value of a list of tuples for the first element.

data = [(0,'a'),(3,'d'),(2,'r'),(1,'m')]

print(max(data, key=lambda x: x[0]))

#Output:
(3,'d')

Finding Minimum Value of List with min() in Python

If you want to go the other way and find the min value of a list, you can use the Python min() function.

min() works the same as max and returns the smallest value of the list.

Below is a simple example showing you how to use min() in Python.

list_of_numbers = [10,32,98,38,47,34]

print(max(list_of_numbers))

#Output
10

Hopefully this article has been useful for you to learn how to get the maximum value of a list in Python with max().