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Tuples are used to store multiple items in a single variable. A tuple is a collection which is ordered and unchangeable. Tuples are written with round brackets. When we say that tuples are ordered, it means that the items have a defined order, and that order will not change. Tuples are unchangeable, meaning that we cannot change, add or remove items after the tuple has been created.
There are 2 ways to create a tuple. The easiest way is to enclose a sequence of comma-separated values within parentheses. The second way to create tuple is to pass a set, list or tuple in a tuple() function.
Code Example 1:
#Create tuple
thistuple = ("Red", "Green", "Blue")
print(thistuple)
#Output:
('Red', 'Green', 'Blue')
Code Example 2:
#Create tuple from list
myList = ["A", "B", "C"]
myTuple=tuple(myList)
print(myTuple)
#Output:
('A', 'B','C')
Code Example 3:
#Create tuple from set
mySet = {"1", "2", "3"}
myTuple=tuple(mySet)
print(myTuple)
#Output:
('3', '1','2')
Code Example 4:
#Create tuple from tuple
myTuple = ("X", "Y", "Z")
myTuple=tuple(myTuple)
print(myTuple)
#Output:
('X', 'Y','Z')
Tuple allows the duplicates values.
Code Example 5:
#Create tuple
thistuple = ("Kansas", "Nevada", "Kansas")
print(thistuple)
#Output:
('Kansas', 'Nevada', 'Kansas')
You can access items in tuple by referring to the index number, inside square brackets as shown below:
Code Example 6:
#Create tuple
thistuple = ("Kansas", "Texas", "Nevada")
print(thistuple[1])
#Output:
Kansas
Negative indexing means start from the end. For example, -1 refers to the last item, -2 refers to the second last item etc.
Code Example 7:
#Print the last item of the tuple
thistuple = ("Kansas", "Texas", "Nevada")
print(thistuple[-1])
#Output:
Nevada
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 tuple with the specified items.
Code Example 8:
#Return the third and fourth items
thistuple=("Green", "Blue", "Red", "Yellow")
print(thistuple[1:3])
#Output:
('Blue', 'Red')
Tuples are unchangeable, that means items cannot be changed, added, or removed once a tuple is created. There is a workaround update, add, and remove items in the tuple. But there is a workaround. You can convert the tuple into a list, change the list, and convert the list back into a tuple..
#This will create a tuple
x = ("Red", "Green", "Blue")
#This is will convert the Tuple x to List y.
y = list(x)
#Update an item in the List
y[1]="Yellow"
#Convert it back to Tuple
x = tuple(y)
#Print
print(x)
#Output:
("Red", "Yellow", "Blue")
To add an item to tuple, you will convert the existing Tuple to List and add the item and convert it back to Tuple.
Example Code 6
#Create a tuple. x = ("Red", "Green", "Blue") #Convert the Tuple x to List y. y = list(x) """Add another color to the tuple, you will convert the existing Tuple to List, add the item and convert it back to Tuple""" y.append("Purple") #Convert it back to Tuple x = tuple(y) #print print(x) #Output: ("Red", "Green", "Blue", "Purple")
Since Tuples are unchangeable, you cannot remove items from it. But there is a workaround. You can convert Tuple to list, remove an item and convert it back to the Tuple.
Example Code 7
y = ("Red", "Green", "Blue") x = list(y) #Remove an item y.remove("Green") #Convert it back to Tuple. x = tuple(y) #print print(x) #Output: ('Red', 'Blue')
When a tuple is created, values are assigned to it. It is called "packing" a tuple..
Example Code 8
colors = ("Red", "Green", "Blue") #We extract the values back into variables. This is called "unpacking" (color1, color2, color3) = colors #print print(x) #Output: Red Green Blue