Tuples

Tuples are used to store multiple items in a single variable

Tuples are one of 4 built-in data types in Python used to store collections of data

Tuples are written with round brackets ( )

A tuple is ordered, immutable & indexed, and allow duplicates and its is faster performance than a list/p>

  mytuple = ("red", "green", "blue")
  print(mytuple)   #Output: ('red', 'green', 'blue'

Tuple Items are Ordered

mytuple = ("red", "green", "blue")
print(mytuple[0])  #Output: red
print(mytuple[1])  #Output: green
print(mytuple[2])  #Output: blue

Immutable

We cannot change, add or remove items after the tuple has been created.

mytuple = ("red", "green", "blue")
mytuple[0] = "yellow"

TypeError: 'tuple' object does not support item assignment

Tuple Items - Data Types

A tuple can contain different data types

tuple1 = ("apple", 1, "banana", 2, "cherry", 3.5, True, False)
print(tuple1)  #Output ('apple', 1, 'banana', 2, 'cherry', 3.5, True, False)

tuple() Constructor

Using the tuple() constructor to make a tuple

  thistuple = tuple(("apple", "banana", "cherry"))
  print(thistuple)   #Output: ('apple', 'banana', 'cherry')

  thislist = ['apple', 'banana', 'cherry']
  thislist_to_tuple = tuple(thislist)
  print(thislist_to_tuple)  #Output: ('apple', 'banana', 'cherry')

Accessing an Items

Tuple items are indexed and you can access them by referring to the index number

thistuple = ("Leo", "Matt", "Kane", "Scott", "Peter", "Will")

Syntax

thistuple = ("Leo", "Matt", "Kane", "Scott", "Peter", "Will")
# Indexing
print(thistuple[0]) #Output: Leo
print(thistuple[1]) #Output: Matt
print(thistuple[2]) #Output: Kane
print(thistuple[3]) #Output: Scott
print(thistuple[4]) #Output: Peter
print(thistuple[5]) #Output: Will

# Negative Indexing
print(thistuple[-6]) #Output: Leo
print(thistuple[-5]) #Output: Matt
print(thistuple[-4]) #Output: Kane
print(thistuple[-3]) #Output: Scott
print(thistuple[-2]) #Output: Peter
print(thistuple[-1]) #Output: Will

Range of Indexes

You can specify a range of indexes by specifying where to start and where to end the range.

When specifying a range, the return value will be a new list with the specified items.

The returned value will include the specified start index and it exclude the specified end index.

thistuple = ("Leo", "Matt", "Kane", "Scott", "Peter", "Will")

print(thistuple[2:5]) #Output: ("Kane", "Scott", "Peter")

Start index: 2

End index: 5

Index 2, Kane is included and index 5, will not included

Remember that the start\first item has index 0

By leaving out the start value, the range will start at the first item:

thistuple = ("Leo", "Matt", "Kane", "Scott", "Peter", "Will")
print(thistuple[:4]) #Output: ('Leo', 'Matt', 'Kane', 'Scott')

By leaving out the end value, the range will go on to the end of the list:

thistuple = ("Leo", "Matt", "Kane", "Scott", "Peter", "Will")
print(thistuple[2:]) #Output: ('Kane', 'Scott', 'Peter', 'Will')

Range of Negative Indexes

Specify negative indexes if you want to start the search from the end of the list:

thistuple = ("Leo", "Matt", "Kane", "Scott", "Peter", "Will")
print(thistuple[-4:-1]) #Output: ('Kane', 'Scott', 'Peter')

Start index: -4

End index: -1

Index -4, Kane is included and index -1, will not included

Remember that the start\first item has negative index -1

Some Important Tuple Methods

Method	Description
count()	Returns the number of times a specified value occurs in a tuple
index()	Searches the tuple for a specified value and returns the position of where it was found

count()

returns the number of occurrence of the specified value

number_tuple = (1,2,3,4,5)

print(number_tuple.count(3))       #Output: 1
print(number_tuple.count(1))       #Output: 2

print(len(number_tuple))           #Output: 5

index()

returns the index of the first element with the specified value

Syntax

mytuple.index(value,start_index(optional),end_index(optional))

Example

number_tuple = (1,2,3,4,5)

return_index1 = number_tuple.index(1)
print(return_index1)    #Output: 0

return_index2 = number_tuple.index(1,3,6)
print(return_index2)    #Output: 5

return_index3 = number_tuple.index(1,3,)
print(return_index3)    #Output: 5

Tuple Unpacking

Unpacking in python refers to an operation that consists of assigning an iterable of values to a tuple (or list ) of variables in a single assignment statement by using the iterable unpacking operator, *

#Example 1
a, b, c = (1, 2, 3)
print(a)
print(b)
print(c)

#Example 2
a, b, c, *others = (1, 2, 3, 4, 5, 6, 7, 8, 9)
print(a)
print(b)
print(c)
print(others)

#Example 2
a, b, c, *others, d= (1, 2, 3, 4, 5, 6, 7, 8, 9)
print(a)
print(b)
print(c)
print(others)
print(d)

Try it yourself

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