Python Arrays

An Array is a collection of similar type of data.

Array in Python can be created by importing the array module.

Syntax

array(data type, [array list])

Example

    from array import array

nums = array("i", [1, 3, 44, 56, 77, 8])
print("int nums = ", end = "")
for i in range(len(nums)):
    print(nums[i], end = " ")
print()

nums = array("d", [1.3, 3.5, 44.46, 56.3])
print("double nums = ", end = "")
for i in range(len(nums)):
    print(nums[i], end = " ")
  
Output
int nums = 1 3 44 56 77 8
double nums = 1.3 3.5 44.46 56.3

While creating an array, the first argument you need to provide is the data type of the array values. The following table will help you create arrays of different types:

Type Code C Type Python Type Minimum Size in bytes
'b' signed char int 1
'B' unsigned char int 1
'u' Py_UNICODE Unicode Character 2
'h' signed short int 2
'H' unsigned short int 2
'i' signed int int 2
'I' unsigned int int 2
'l' unsigned long int 4
'L' unsigned long int 4
'f' float int 4
'd' double int 8

Array Methods

Some of the useful array methods are given below:

Method Description
append() Adds an item at the end of an array.
clear() Removes all items from an array.
count() Returns the number of items in an array.
copy() Return copy of an array.
extend() Adds multiple items at the end of an array.
insert() Adds an item at the specified index of an array.
pop() Removes an item from the specified index of an array.
remove() Removes the specified item from an array.
reverse() Reverses the order of items in an array.
sort() Sorts the order of items in an array.

Access Items of an Array

To access items of array, you can use the square brackets with index.

Syntax

array[index]

Example

        from array import array
        nums = array("i", [1, 3, 44, 56, 77, 8])
        print(nums[2])
  
Output
44

Add Item in an Array

To add item in an array, you can use the append() method.

Example

        from array import array

nums = array("i", [1, 3, 44, 56, 77, 8])
print("nums before = ", end = "")
for i in range(len(nums)):
    print(nums[i], end = " ")
print()

#add new value
nums.append(55)
print("nums after = ", end = "")
for i in range(len(nums)):
    print(nums[i], end = " ")
  
Output
nums before = 1 3 44 56 77 8
nums after = 1 3 44 56 77 8 55

Insert Item in an Array

To insert an item at the specified index of an array, you can use the insert() method.

Syntax

insert(index, item)

Example

            from array import array

nums = array("i", [1, 3, 44, 56, 77, 8])
print("nums before = ", end = "")
for i in range(len(nums)):
    print(nums[i], end = " ")
print()

#add new value
nums.insert(0,55)
print("nums after = ", end = "")
for i in range(len(nums)):
    print(nums[i], end = " ")
  
Output
nums before = 1 3 44 56 77 8
nums after = 55 3 44 56 77 8

Remove Item from an Array

To remove an item from an array, you can use the remove() method.

Example

            from array import array

nums = array("i", [1, 3, 44, 56, 77, 8])
print("nums before = ", end = "")
for i in range(len(nums)):
    print(nums[i], end = " ")
print()

#remove value
nums.remove(77)
print("nums after = ", end = "")
for i in range(len(nums)):
    print(nums[i], end = " ")
  
Output
nums before = 1 3 44 56 77 8
nums after = 1 3 44 56 8

Pop Item from an Array

To remove an item at the specified index of an array, you can use the pop() method.

Syntax

pop(index)

Example

                from array import array

nums = array("i", [1, 3, 44, 56, 77, 8])
print("nums before = ", end = "")
for i in range(len(nums)):
    print(nums[i], end = " ")
print()

#remove value at specified index
nums.pop(2)
print("nums after = ", end = "")
for i in range(len(nums)):
    print(nums[i], end = " ")
  
Output
nums before = 1 3 44 56 77 8
nums after = 1 3 56 77 8