A basic tutorial to Enumerate() in Python - Handle data and datasets easily

Python is one of the most popular programming languages in the current IT landscape. The primary reason behind this popularity is it can easily integrate with modern technologies like data science, artificial intelligence, etc. Albeit that it offers a variety of functions that aids heavily during web development and application development. 

One similar built-in function is enumerate in Python. In this article, we explain the different facets of Python enumerate function. Facets such as the syntax, the parameters, and the different examples associated with Python function enumerate.

What are some Python Basics?

Python for mobile apps development is many companies' first choice. It is because Python is a high-level language-interpreted programming language. Python is often referred to for its simplicity and ease of usage. Here are some basics about Python that one must know about:

• Variables: These are the elements in the Python basics that are used for storing the value. The value in a Python variable is assigned using ‘=’ operator.
• Data Types: Basics of Python several data types that can be used such as integers, floats, boolean, strings, and lists. These variables in Python can be determined using type().
• Operators: Basics of Python comprises of multiple operators that can be used for mathematical as well as logical operations. Some common operators used are “+,-,*,/,=,==,<,>”.
• Control Structures: These are loops and conditional statements that control the flow of the program. In Python basics there are several if statements, for loops, and while loops that are considered.
• Functions: These are block of codes that are used to perform a specific task.
• Comments: These are used for creating notes inside a program. In python, to write a comment we use the symbol “#”.

Python Enumerate Function - Syntax and Parameters

Enumerate in Python is used to iterate over a sequence of lists, tuples, or strings. Once the Python enumerate function does its operations then it returns an enumerated object. Below is the syntax for Python function enumerate:

Enumerate(sequence, start=0)

Here “sequence” is the parameter that will be iterated over. The “start” parameter is optional in nature and is used for specifying the start value of the index. However, if this optional parameter is not used, the default value will be considered 0.

Example of Enumerate in Python

 

Example 1: Python Enumerate Function for List

Cars = [‘Bentley’, ‘Mercedes’, ‘Audi’]

For index, Cars in enumerate(Cars):
print(index, cars)

Output:

• 0 Bentley
• 1 Mercedes
• 2 Audi

Example 2: Enumerate in Python for Tuple

Cars = (‘Bentley’, ‘Mercedes’, ‘Audi’)

For index, Cars in enumerate(Cars, Start=1):
print(index, Cars)

Output:

• 1 Bentley
• 2 Mercedes
• 3 Audi

Example 3: Python Function Enumerate for String

Text = ‘MobileAppDaily’

For index, character in enumerate(text):
print(index, character)

Output:

• 0 M
• 1 o
• 2 b
• 3 i
• 4 l
• 5 e
• 6 A
• 7 p
• 8 p
• 9 D
• 10 a
• 11 i
• 12 l
• 13 y

Enumerate in Python - Common Errors and Mistakes

While implementing the Python function enumerate, there are some important things to keep in mind that create some common errors and mistakes.

Common errors while using Enumerate in Python

• Forgetting to unpack the tuple that is returned by enumerate()
• Using an out-of-range index value
• Changing the length of the sequence that is being enumerated during the iteration

Ways to avoid these errors!

• Make sure to unpack the tuple returned after the enumerate() function has been executed
• Always use the len() function in order to figure out the length of the sequence and run out of range
• Don’t change the length of the sequence during iterations

What does enumerate do in Python?

There are several functions of enumerate in Python. We have listed the important use cases:

Use Case 1: Enumerate list of Objects

Let’s start with the object “Cars” below:

Class Cars:

The objective here would be to iterate the object “Cars” and print out the names along with the index. To do that we will use the enumerate in Python function. Have a look at the code below:

Car_Company = [Cars(‘Bentley’), Cars(‘Mercedes’), Cars(‘Audi’)]

For index, Cars in enumerate(Car_Company):
print(index, Cars.Car_Name)

Output:

• 0 Bentley
• 1 Mercedes
• 2 Audi

Use Case 2: Enumerating list of Tuples

Now, let’s take the example of tuple representing a dataset. In this tuple, the first element is a label and the remaining are the data points. The task here is to iterate the list and print out each and every label that corresponds to its data points. To do this, we can use the enumerate function. Let’s see the code first:

Student_Age = [(‘class A age’, 10, 11, 10), (‘class B age’, 12,10,11), (‘class C age’, 10, 10, 11)]
For index, (labe, *Student_Age) in enumerate(Student_Age):
print(index, label, Student_Age)

Output:

• 0 class A age [10, 11, 10]
• 1 class B age [12, 10, 11]
• 2 class C age [10, 10, 11]

Use Case 3: Enumerating a dictionary

Now, let’s suppose we have a dictionary of word that are mapped from word to their corresponding frequency counts. To iterate the dictionary and print out each and every word along with its frequency count, we can use the enumerate function. Let’s check the code for that:

Word_counts = {‘Bentley’:3, ‘Mercedes’:2, ‘Audi’:1}

For index, (word, count) in enumerate(word_counts.items()):
print(index, word, count)

Output:

• 0 Bentley 3
• 1 Mercedes 2
• 2 Audi 1

A majority of mobile app development companies are using Python simply for the ease of these function. The enumerate in Python is a useful built-in function that is used in Python for iterating sequences and keeping track of the index. The Python enumerate function can be used in multiple case scenarios that include working with objects, tuples, and dictionaries. There are alternatives, however, it becomes easier to accomplish this task using the enumerate in Python function.