Python - Access Array Items (Complete Guide for Beginners)

 In Python, arrays allow you to store multiple values in a single variable. Once an array is created, you often need to access individual items to read or use the data.

In this tutorial, you will learn how to access array items in Python using index numbers, negative indexing, and looping techniques.

---

What is Array Indexing?

Array indexing means accessing elements using their position number.

Example Concept:

Index:   0   1   2   3
Array:  10  20  30  40

• Index starts from 0
• First element is at index 0
• Last element is at index (n-1)

---

Creating an Array

We use Python’s array module.

import array as arr

numbers = arr.array('i', [10, 20, 30, 40, 50])

---

1. Access Array Items Using Index

You can access elements using square brackets [].

Example

print(numbers[0])
print(numbers[2])
print(numbers[4])

Output

10
30
50

Explanation

• numbers[0] → first element
• numbers[2] → third element
• numbers[4] → fifth element

---

2. Negative Indexing

Python allows accessing elements from the end using negative index.

Example

print(numbers[-1])
print(numbers[-2])

Output

50
40

Explanation

Index	Value
-1	Last element
-2	Second last

---

3. Access Array Items Using Loop

You can access all elements using a loop.

Example

for item in numbers:
    print(item)

Output

10
20
30
40
50

---

4. Access Array Items Using Index Loop

Example

for i in range(len(numbers)):
    print(numbers[i])

Output

10
20
30
40
50

---

5. Access Array Item by Condition

You can access items based on conditions.

Example: Print values greater than 25

for item in numbers:
    if item > 25:
        print(item)

Output

30
40
50

---

6. Access Specific Range (Slicing Concept with List Conversion)

Python arrays do not support slicing directly like lists, but you can convert them.

Example

print(numbers[1:4])

Output

array('i', [20, 30, 40])

---

7. Access First and Last Elements

Example

print("First:", numbers[0])
print("Last:", numbers[-1])

Output

First: 10
Last: 50

---

Real-World Example: Student Marks

import array as arr

marks = arr.array('i', [85, 90, 78, 88, 92])

print("First Mark:", marks[0])
print("Highest Index Mark:", marks[-1])

---

Real-World Example: Product Prices

import array as arr

prices = arr.array('f', [99.99, 149.50, 200.75])

for price in prices:
    print("Price:", price)

---

Common Mistakes

Mistake 1: Using Out-of-Range Index

❌ Wrong

print(numbers[10])

✔ Result: IndexError

---

Mistake 2: Forgetting Index Starts at 0

❌ Wrong assumption:

First element = 1

✔ Correct:

First element = 0 index

---

Mistake 3: Mixing Array Types

arr.array('i', [10, "hello", 20])

✔ Only same data type is allowed

---

Array Access Methods Summary

Method	Description
index [0]	Access first element
index [-1]	Access last element
loop	Access all elements
range loop	Access by index
condition	Filter values
slicing	Access range of items

---

Practice Exercise 1

Print the second and fourth element of an array.

---

Practice Exercise 2

Print all elements greater than 50.

---

Conclusion

Accessing array items in Python is simple and powerful. You can use:

• Positive indexing
• Negative indexing
• Loops
• Conditions
• Range-based access

Understanding array access is essential for working with data processing, scientific computing, and real-world applications.