Python Tuples
Tuples
A tuple is a container which holds a series of comma-separated values (items or elements) between parentheses such as an (x, y) co-ordinate. Tuples are like lists, except they are immutable (i.e. you cannot change its content once created) and can hold mix data types. Tuples play a sort of "struct" role in Python -- a convenient way to pass around a little logical, fixed size bundle of values.
Contents:
- Tuple commands
- Create a tuple
- How to get an item of the tuple in Python?
- How to know if an element exists within a tuple in Python?
- List to tuple
- Unpack a tuple in several variables
- Add item in Python tuple!
- Clone a tuple
- In Python how to know the number of times an item has repeated
- Remove an item from a tuple
- Slice a tuple
- How to get the index of an item of the tuple in Python?
- The size of a tuple
- How operators + and * are used with a Python tuple?
- Slice of a tuple using step parameter.
- Modify items of a tuple
- Python Data Types: Tuple - Exercises, Practice, Solution
Tuple: Commands
Tuple is an immutable and hashable list.
<tuple> = ()<tuple> = (<el>, )<tuple> = (<el_1>, <el_2> [, ...])
Named Tuple
Tuple's subclass with named elements.
>>> from collections import namedtuple>>> Point = namedtuple('Point', 'x y')>>> p = Point(1, y=2)Point(x=1, y=2)>>> p[0]1>>> p.x1>>> getattr(p, 'y')2>>> p._fields # Or: Point._fields('x', 'y')Create a tuple?
To create a tuple, just list the values within parenthesis separated by commas. The "empty" tuple is just an empty pair of parenthesis
>>> #create an empty tuple>>> tuplex = ()>>> print (tuplex)()>>> #create a tuple with different data types>>> tuplex = ('tuple', False, 3.2, 1)>>> print (tuplex)('tuple', False, 3.2, 1)>>> #create a tuple with numbers, notation without parenthesis>>> tuplex = 4, 7, 3, 8, 1 >>> print (tuplex)(4, 7, 3, 8, 1)>>> #create a tuple of one item, notation without parenthesis>>> tuplex = 4, >>> print (tuplex)(4,)>>> #create an empty tuple with tuple() function built-in Python>>> tuplex = tuple()>>> print (tuplex)()>>> #create a tuple from a iterable object>>> tuplex = tuple([True, False]) >>> print (tuplex)(True, False)>>>How to get an item of the tuple in Python?
>>> #create a tuple>>> tuplex = ("w", 3, "r", "e", "s", "o", "u", "r", "c", "e") >>> print(tuplex)('w', 3, 'r', 'e', 's', 'o', 'u', 'r', 'c', 'e')>>> #get item (4th element)of the tuple by index>>> item = tuplex[3]>>> print(item)e>>> #get item (4th element from last)by index negative>>> item1 = tuplex[-4]>>> print(item1)u>>>How to know if an element exists within a tuple in Python?
>>> #create a tuple>>> tuplex = ("w", 3, "r", "e", "s", "o", "u", "r", "c", "e")>>> print(tuplex)('w', 3, 'r', 'e', 's', 'o', 'u', 'r', 'c', 'e')>>> #use in statement>>> print("r" in tuplex)True>>> print(5 in tuplex)False>>>List to tuple
>>> #create list>>> listx = [5, 10, 7, 4, 15, 3]>>> print(listx)[5, 10, 7, 4, 15, 3]>>> #use the tuple() function built-in Python, passing as parameter the list>>> tuplex = tuple(listx)>>> print(tuplex)(5, 10, 7, 4, 15, 3)>>>Unpack a tuple in several variables
>>> #create a tuple>>> tuplex = 4, 8, 3 >>> print(tuplex)(4, 8, 3)>>> n1, n2, n3 = tuplex>>> #unpack a tuple in variables>>> print(n1 + n2 + n3) 15>>> #the number of variables must be equal to the number of items of the tuple>>> n1, n2, n3, n4 = tuplex Traceback (most recent call last): File "<stdin>", line 1, in <module>ValueError: need more than 3 values to unpack>>>Add item in Python tuple!
>>> #create a tuple>>> tuplex = (4, 6, 2, 8, 3, 1) >>> print(tuplex)(4, 6, 2, 8, 3, 1)>>> #tuples are immutable, so you can not add new elements>>> #using merge of tuples with the + operator you can add an element and it will create a new tuple>>> tuplex = tuplex + (9,)>>> print(tuplex)(4, 6, 2, 8, 3, 1, 9)>>> #adding items in a specific index>>> tuplex = tuplex[:5] + (15, 20, 25) + tuplex[:5]>>> print(tuplex)(4, 6, 2, 8, 3, 15, 20, 25, 4, 6, 2, 8, 3)>>> #converting the tuple to list>>> listx = list(tuplex) >>> #use different ways to add items in list>>> listx.append(30)>>> tuplex = tuple(listx)>>> print(tuplex)(4, 6, 2, 8, 3, 15, 20, 25, 4, 6, 2, 8, 3, 30)>>>Clone a tuple
>>> from copy import deepcopy>>> #create a tuple>>> tuplex = ("HELLO", 5, [], True) >>> print(tuplex)('HELLO', 5, [], True)>>> #make a copy of a tuple using deepcopy() function>>> tuplex_clone = deepcopy(tuplex)>>> tuplex_clone[2].append(50)>>> print(tuplex_clone)('HELLO', 5, [50], True)>>> print(tuplex)('HELLO', 5, [], True)>>>In Python how to know the number of times an item has repeated
>>> #create a tuple>>> tuplex = 2, 4, 5, 6, 2, 3, 4, 4, 7 >>> print(tuplex)(2, 4, 5, 6, 2, 3, 4, 4, 7)>>> #return the number of times it appears in the tuple.>>> count = tuplex.count(4)>>> print(count)3>>> count = tuplex.count(7)>>> print(count)1>>> count = tuplex.count(5)>>> print (count)1>>>Remove an item from a tuple
>>> #create a tuple>>> tuplex = "w", 3, "d", "r", "e", "s", "l" >>> print(tuplex)('w', 3, 'd', 'r', 'e', 's', 'l')>>> #tuples are immutable, so you can not remove elements>>> #using merge of tuples with the + operator you can remove an item and it will create a new tuple>>> tuplex = tuplex[:2] + tuplex[3:]>>> print(tuplex)('w', 3, 'r', 'e', 's', 'l')>>> #converting the tuple to list>>> listx = list(tuplex) >>> #use different ways to remove an item of the list>>> listx.remove("l") >>> #converting the tuple to list>>> tuplex = tuple(listx) >>> print(tuplex)('w', 3, 'r', 'e', 's')>>>Slice a tuple
>>> #create a tuple>>> tuplex = (2, 4, 3, 5, 4, 6, 7, 8, 6, 1) >>> #used tuple[start:stop] the start index is inclusive and the stop index>>> _slice = tuplex[3:5] #is exclusive.>>> print(_slice)(5, 4)>>> #if the start index isn't defined, is taken from the beg inning of the tuple.>>> _slice = tuplex[:6]>>> print(_slice)(2, 4, 3, 5, 4, 6)>>> #if the end index isn't defined, is taken until the end of the tuple>>> _slice = tuplex[5:] >>> print(_slice)(6, 7, 8, 6, 1)>>> #if neither is defined, returns the full tuple>>> _slice = tuplex[:]>>> print(_slice)(2, 4, 3, 5, 4, 6, 7, 8, 6, 1)>>> #The indexes can be defined with negative values>>> _slice = tuplex[-8:-4] >>> print(_slice)(3, 5, 4, 6)>>>Find the index of an item of the tuple
>>> #create a tuple>>> tuplex = tuple("index tuple") >>> print(tuplex)('i', 'n', 'd', 'e', 'x', ' ', 't', 'u', 'p', 'l', 'e')>>> #get index of the first item whose value is passed as parameter>>> index = tuplex.index("p") >>> print(index)8>>> #define the index from which you want to search>>> index = tuplex.index("p", 5) >>> print(index)8>>> #define the segment of the tuple to be searched>>> index = tuplex.index("e", 3, 6) >>> print(index)3>>> #if item not exists in the tuple return ValueError Exception>>> index = tuplex.index("y")Traceback (most recent call last): File "<stdin>", line 1, in <module>ValueError: tuple.index(x): x not in tuple>>>The size of a tuple
>>> tuplex = tuple("w3resource")#create a tuple>>> print(tuplex)('w', '3', 'r', 'e', 's', 'o', 'u', 'r', 'c', 'e')>>> #use the len() function to known the length of tuple.>>> print(len(tuplex))10>>>How operators + and * are used with a Python tuple?
>>> #create a tuple>>> tuplex = 5, #create a tuple>>> #The * operator allow repeat the items in the tuple>>> print(tuplex * 6) (5, 5, 5, 5, 5, 5)>>> #create a tuple with repeated items.>>> tuplex = (5, 10, 15) * 4 >>> print(tuplex)(5, 10, 15, 5, 10, 15, 5, 10, 15, 5, 10, 15)>>> #create three tuples>>> tuplex1 = (3, 6, 9, 12, 15) >>> tuplex2 = ("w", 3, "r", "s", "o", "u", "r", "c", "e")>>> tuplex3 = (True, False)>>> #The + operator allow create a tuple joining two or more tuples>>> tuplex = tuplex1 + tuplex2 + tuplex3>>> print(tuplex)(3, 6, 9, 12, 15, 'w', 3, 'r', 's', 'o', 'u', 'r', 'c', 'e', True, False)>>>Slice of a tuple using step parameter
>>> #create a tuple>>> tuplex = tuple("HELLO WORLD") >>> print(tuplex)('H', 'E', 'L', 'L', 'O', ' ', 'W', 'O', 'R', 'L', 'D')>>> #step specify an increment between the elements to cut of the tuple.>>> _slice = tuplex[2:9:2]#tuple[start:stop:step]>>> print(_slice)('L', 'O', 'W', 'R')>>> #returns a tuple with a jump every 3 items.>>> _slice = tuplex[::4] >>> print(_slice)('H', 'O', 'R')>>> #when step is negative the jump is made back>>> _slice = tuplex[9:2:-4] >>> print(_slice)('L', ' ')>>> #when step is negative the jump is made back>>> _slice = tuplex[9:2:-3] >>> print(_slice)('L', 'W', 'L')>>>Modify items of a tuple
>>> #create a tuple>>> tuplex = ("w", 3, "r", [], False)>>> print(tuplex)('w', 3, 'r', [], False)>>> #tuples are immutable, so you can not modify items which are also immutable, as str, boolean, numbers etc.>>> tuplex[3].append(200)>>> print(tuplex)('w', 3, 'r', [200], False)>>>Previous: Python Dictionary
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