Python Basic Tutorials

Python is a high level general purpose programming language which has a clear/easy learning curve. Python programming language is massively used in various domains like Artificial Intelligence, Data Science, Web Development, Utilities Tools and Scripts and many more

Python is a Programming language, and the default Python we use is written in C programming language which is also referred to as CPython (Python implementation in C). There are various implementation of Python Programming language i.e Jython(in JAVA), Skulpt(in JS) e.t.c

To make everything easy: We refer CPython as Python

Python Array

Basically, the array is the collection of similar kinds of data types. In arrays, elements are stored in contiguous memory locations. Python arrays are similar to the python list but the difference is python array can contain elements of similar types only. Similar to the python lists, indexing is possible in python arrays.

Creating a Python Array

Python array can be created by importing array module. In python, to create an array, we need to first declare the code of data type of the elements.

Syntax of the array is given as:

>>>array(data_type_code, value_list)

So, during the creation of an array, we've to first write the datatypes and then corresponding value_list. These are enclosed inside the () brackets.

Now, let's create an array.

import array as arr

print("The Array elements are:\n")
for i in arr1:
    print(1,end=" ")

The Array elements are:
1 2 4 3 5 6
Different datatype's specification codes used are listed below:
Code C Type Python Type Min byte
b signed char int 1
B unsigned char Unicode 2
u Py_UNICODE Unicode 2
h signed short int 2
H unsigned short int 2
i signed int int 2
l signed long int 4
L unsigned long int 4
f float float 4
d double float 8
Accessing Array Items

To access array items use simply use array indexing. Which is similar to list indexing.

#program that access the array elements.
alpha_Array = arr.array('u', ['a','b','c','d','e'])

print("First Element: ",alpha_Array[0])
print("Last Elements: " ,alpha_Array [-1])
print("Second Last Element: ", alpha_Array[-2])

First Element: a
Last Elements: e
Second Last Element: d
Modifying array items-Adding items to the array.

Arrays are almost similar to lists. We can use append(), insert(), extend(), etc functions to perform some modifications.

  • The append() method is used to insert the element at the last of the array.
  • The insert() method is used to insert the element wherever you want, by giving the required position index in the function.
  • The extend() method is used to merge two iterables in the array. We can simply merge another list having the same kind of element to an array.

>>>alpha_array = arr.array('u', ['a','b','c','d','e'])
   array('u', 'abcde')

   array('u', 'abcdef')

   array('u', 'zabcdeyf')

   array('u', 'zabcdeyfrst')
Removing items from an Array

We can simply use del statement, remove(), pop(), etc functions in an array to remove items just similarly we do in a list.

  • The del statement: Using the del statement we can remove elements from anywhere, by giving the required index number.
  • The pop() method: Using the pop() method we can remove the items from the last.
  • The remove() method: The remove() method is used to remove the element from an array by passing the element to be deleted from an array to remove() method.

>>>#Program to delete items from an array with different methods.
>>>alpha_array = arr.array('u', ['Z','a','b','c','d','e','y','f','r','s','t'])
   array('u', 'Zabcdeyfrst')

>>>#The pop() method.
   array('u', 'Zabcdeyfr')

>>>#The del statement.
>>>del alpha_array[0]
   array('u', 'acdeyfr')

>>>#The remove() method.
   array('u', 'abeyfr')
Slicing an Array

We can access the required range of elements by slicing an array. It is done using the slicing operator(':').


>>>import array as arr
>>>int_array = arr.array('i',[23,3,4,2,5,45,6,3,65,43])
>>>print(int_array[:]) #prints all items.
   array('i', [23, 3, 4, 2, 5, 45, 6, 3, 65, 43])

>>>print(int_array[1:]) #prints 1st index to end.
   array('i', [3, 4, 2, 5, 45, 6, 3, 65, 43])

>>>print(int_array[:-1]) #prints second last index to beginning.
   array('i', [23, 3, 4, 2, 5, 45, 6, 3, 65])

>>>print(int_array[2:6]) #prints second index to fifth index.
   array('i', [4, 2, 5, 45])

>>>print(int_array[:-6]) #prints beginning to 5th index.
   array('i', [23, 3, 4, 2])

Changing items with slicing

We can use slicing to insert, replace and delete items from an array. We can modify it for the required range of items using slicing.


>>>import array as arr
>>>arr1 = arr.array('i',[1,2,4,5,6])
   array('i', [1, 2, 4, 5, 6])

>>>arr1[1:4]= arr.array('i',[8,9,10]) #replaces 1st, 2nd and 3rd indexes.
   array('i', [1, 8, 9, 10, 6])

>>>del arr1[1:3] #delete 1st & 2nd indexes.
   array('i', [1, 10, 6])
Seaching items in an array.

We can find the index of a particular element of an array by using the index() method.


import array as arr
arr1 = arr.array('i',[1,2,3,4,5,6])

print("Index of 3 is: ", arr1.index(3))
print("Index of 4 is: ",arr1.index(4))

print("\nIndex of whole items of an array.")
for i in range(6):
    print(f"Index of {arr1[i]}: ",arr1.index(arr1[i]))


array('i', [1, 2, 3, 4, 5, 6])
Index of 3 is: 2
Index of 4 is: 3

Index of whole items of an array.
Index of 1: 0
Index of 2: 1
Index of 3: 2
Index of 4: 3
Index of 5: 4
Index of 6: 5