# Python Program to get the first item from the array

In programming array is a data structure, which is used to store collection of homogeneous data elements. And each element in the array is identified by an index value or key.

## Arrays in Python

Python doesn’t have a built-in data structure to represent arrays, but it has a built-in array module for arrays. And also we can use the NumPy package to work with arrays in python.

An array defined by the array module is −

array('i', [1, 2, 3, 4])


A Numpy array defined by the NumPy module is

array([1, 2, 3, 4])


Also, we can use the list data structure to represent arrays, for that we need to store homogeneous items into the list.

## Input Output Scenarios

Let’s see the below input output scenarios to understand how to get the first item from the array. Assume we have an array with 4 elements. And in output array the first element will be displayed.

Input array:
[1, 2, 3, 4, 5]
Output:
[1]


Below examples we will use indexing and slicing features to access the first element from an array.

Python indexing is nothing but accessing the elements of a sequence by using their individual positional values, and it starts from 0 to n-1. In the same way, the slicing is used to access the group of elements from a sequence.

### Syntax

Array[start : end]

• Start  The starting index where slicing of an array starts.

• End  The ending index where slicing of the array stops. This value is not inclusive.

## Using List

The Python lists are zero-indexed, which means the first element is available at index 0.

### Example

# creating array
lst = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

print ("The original array is: ", lst)
print()

# get first element
result = lst[0]
print ("The first element is: ", result)


### Output

The original array is:  [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
The first element is:  1


We accessed the first element by using list indenting lst[0]. Similarly, we can use the slicing to get the first elements. See the below example to get the first elements using slicing.

### Example

# creating array
lst = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
print ("The original array is: ", lst)
print()
# get first element
result = lst[:1]
print ("The first element is: ", result)


### Output

The original array is:  [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
The first element is:  [1]


The slicing syntax [:1] returns a first element then it is stored in the result variable.

## Using Array Module

By using array() method we can converts the python list into an array, and this array also supports the indexing and array slicing.

### Example

Let’s access the first item of an array using the index value.

import array

# creating array
array = array.array('i', [1, 3, 4, 8])

print ("The original array is: ", array)
print()

# get the first element
result = array[0]
print ("The first element is: ", result)


### Output

The original array is:  array('i', [1, 3, 4, 8])

The first element is:  1


### Example

In this example, we will access the first item of an array using the array slicing.

import array
# creating array
array = array.array('i', [1, 3, 4, 8])
print ("The original array is: ", array)
print()
# get the first element
result = array[:1]
print ("The first element is: ", result)


### Output

The original array is:  array('i', [1, 3, 4, 8])
The first element is:  1


The statement array[:1] mean retrieving the array element upto the index value 1.

## Using NumPy Array

Using the numpy array we can easily access the array elements.

### Example

The index of a numpy array also starts from 0.

import numpy
# creating array
numpy_array = numpy.random.randint(1, 10, 4)
print ("The original array is: ", numpy_array)
print()
# get the first element
result = numpy_array[0]
print ("The first element is: ", result)


### Output

The original array is:  [5 4 2 1]
The first element is:  5


In the above example we have accessed the 1st element and the element is 5.

### Example

We can use slicing syntax [:1] to get the first element. Let’s see in the example below.

import numpy
# creating array
numpy_array = numpy.random.randint(1, 10, 4)
print ("The original array is: ", numpy_array)
print()
# get the first element
result = numpy_array[:1]
print ("The first element is: ", result)


### Output

The original array is:  [6 2 1 6]
The first element is:  [6]


The first element 6 is accessed from the numpy using slicing.

Updated on: 29-May-2023

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