Predefined Functions: Length

The Length predefined function allows a user to get the number of characters in a string or the number of items within an array.

The length can be assigned to a variable or used within a condition.

Key Points

Length can count the characters in a string.

Length can count the items in an array.

Length can be assigned to a variable.

Length can be used within a condition.

How to use Length

To use Length, you must write ‘length’ followed by two brackets. Inside the brackets, you must pass a parameter.

The parameter must either be a string or an array.

In the below example, the output would be 5 – the number of characters in the word “Hello”.

word = "Hello"

print(len(word))

In this example, the output would be 3 – the number of items within the array.

fruit = ["Apple", "Pear", "Strawberry"]

print(len(fruit))

Using Length within a condition

The Length of a string or an array can be used within a condition.

The following examples show two different approaches.

The below example first stores the length of a variable before using the variable in the condition.

word = "Hello"

length_of_word = len(word)

if length_of_word == 5:
    print("The word has 5 characters!")

Additionally, the length can be used directly within the condition.

word = "Hello"

if len(word) == 5:
    print("The word has 5 characters!")

National 5 Requirements

You should be able to identify and explain the length predefined function.

You should be able to use the length predefined function within your code.