Posted on Jun 1 • Edited on Nov 6

Tuple in Python (1)

#python #tuple #ordered #immutable

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My post explains tuple functions.
My post explains 10 collection types and their related posts.

A tuple:

is the ordered immutable(hashable) collection of zero or more elements whose type is tuple:
- Ordered means that the order of each element in a tuple is kept so it guarantees that the order is always the same.
- Immutable(Hashable) means the elements of a tuple cannot be changed.
allows duplicated elements.
can have any types of elements.
can be used with len() to get the length.
is True if it's non-empty and False if it's empty, checking it with bool().
is False if it's non-empty and True if it's empty, inverting the truth value with not.
can be checked if a specific element is and isn't in the tuple with in and not in respectively.
can be checked if the tuple is and isn't referred to by two variables with is and is not respectively:
- Be careful, tuple literals with is and is not get warnings so use == and != respectively.
and other tuple can be checked if:
- all the elements in them are and aren't equal with == and != respectively:
  - == and != can also check if types of values are and aren't the same respectively.
- the tuple is greater than other tuple with >.
- the tuple is greater than or equal to other tuple with >=.
- the tuple is less than other tuple with <.
- the tuple is less than or equal to other tuple with <=.
and other tuple cannot be checked if they have and don't have their common elements with bool() and & and with not and & respectively.
can be enlarged with * and a number.
and other tuples can be concatenated with +.
and other tuple cannot return:
- all the elements in them with '|' (Union: A ∪ B).
- their common elements with '&' (Intersection: A ∩ B).
- the elements in the tuple which aren't in other tuple with '-' (Difference: A - B).
- the elements in either the tuple or other tuple but not both with '^' (Symmetric Difference: A Δ B).
can be iterated with a for statement.
can be unpacked with an assignment and for statement, function and * but not with **.
can be created by () and/or ',', by tuple() with or without an iterable and by a tuple comprehension:
- For tuple(), the words type conversion are also suitable in addition to the word creation.
cannot be big because it gets MemoryError.
can be read by indexing and slicing.
cannot be changed by indexing, slicing and a del statement.
can be continuously used through multiple variables.
cannot be shallow-copied by copy.copy(), tuple().
cannot be deep-copied and even shallow-copied by copy.deepcopy().

Be careful, a big tuple gets `MemoryError`.

() and/or ',' can create a tuple as shown below:

v = () # Empty 1D tuple v = (0,) # 1D tuple v = 0, # 1D tuple v = (0) # int not tuple v = 0 # int not tuple v = (0), # 1D tuple v = (0, 1, 2, 3, 4) # 1D tuple v = 0, 1, 2, 3, 4 # 1D tuple v = (0, 1, 2, 0, 1, 2) # 1D tuple v = ((0,),) # 2D tuple v = (((0),)), # 2D tuple v = (0, 1, 2, 3, (4, 5, 6, 7)) # 2D tuple v = ((0, 1, 2, 3), (4, 5, 6, 7)) # 2D tuple v = (((0,),),) # 3D tuple v = (((((0),)),)), # 3D tuple v = ((0, 1, 2, 3), ((4, 5), (6, 7))) # 3D tuple v = (((0, 1), (2, 3)), ((4, 5), (6, 7))) # 3D tuple # No error  print((0, 0.0, 0.0+0.0j, False)) print((1, 1.0, 1.0+0.0j, True)) print(('A', b'A', bytearray(b'A'), 2, 2.3, 2.3+4.5j, True, [2, 3], (2, 3), {2, 3}, frozenset({2, 3}), {'A':'a'}, range(2, 3), iter([2, 3]))) print(len((0, 1, 2, 3, 4))) print(bool((0,))) print(bool(((),))) print(bool(())) print(not (0,)) print(not ((),)) print(not ()) print('A' in ('A', ('B', 'C'))) print('A' not in ('A', ('B', 'C'))) print((0, 1, 2) is (0, 1, 2)) # It gets warning so use `==`. print((0, 1, 2) is not (0, 1, 2)) # It gets warning so use `!=`. print((0, 1, 2) == (0, 1, 2)) print((0, 1, 2) != (0, 1, 2)) print((0, 1, 2) <= (0, 1, 2)) print((0, 1, 2) >= (0, 1, 2)) print((0, 1, 2) < (0, 1, 2)) print((0, 1, 2) > (0, 1, 2)) print((0, 1, 2, 3, 4) * 3) print(('A', 'B', 'C', 'D', 'E') * 3) print(() * 3) print((0, 1, 2) + ((3, 4),) + (((5, 6, 7, 8),),)) for x in (0, 1, 2, 3, 4): print(x) for x in ((0, 1, 2, 3), (4, 5, 6, 7)): print(x) for x in (((0, 1), (2, 3)), ((4, 5), (6, 7))): print(x) v1, v2, v3 = (0, 1, 2); print(v1, v2, v3) v1, *v2, v3 = (0, 1, 2, 3, 4, 5); print(v1, v2, v3) for v1, v2, v3 in ((0, 1, 2), (3, 4, 5)): print(v1, v2, v3) for v1, *v2, v3 in ((0, 1, 2, 3, 4, 5), (6, 7, 8, 9, 10, 11)): print(v1, v2, v3) print(*(0, 1), 2, *(3, 4, *(5,))) print((*(0, 1), 2, *(3, 4, *(5,)))) print(tuple(x**2 for x in (0, 1, 2, 3, 4, 5, 6, 7))) print(tuple(tuple(y**2 for y in x) for x in ((0, 1, 2, 3), (4, 5, 6, 7)))) print(tuple(tuple(tuple(z**2 for z in y) for y in x) for x in (((0, 1), (2, 3)), ((4, 5), (6, 7))))) # No error  print(bool((0, 1, 2) & (1, 3))) print(not ((0, 1, 2) & (1, 3))) print((0, 4) | (0, 2, 4)) print((0, 1, 2, 3) & (0, 2, 4)) print((0, 1, 2, 3) - (0, 2, 4)) print((0, 1, 2, 3) ^ (0, 2, 4)) print((0, 1, 2, 3, 4) * 1000000000) print(tuple(range(1000000000))) print(tuple(x for x in range(1000000000))) # Error

A tuple is the ordered immutable(hashable) collection of zero or more elements whose type is tuple as shown below:

v = (0, 1, 2, 3, 4) v = 0, 1, 2, 3, 4 print(v) # (0, 1, 2, 3, 4)  print(type(v)) # <class 'tuple'>  v[1] = 'X' v[3] = 'Y' # TypeError: 'tuple' object does not support item assignment

v = (0,) v = 0, v = ((0,)) print(v) # (0,)

v = () # Empty tuple  print(v) # ()

A tuple allows duplicated elements as shown below:

v = (0, 1, 2, 0, 1, 2) print(v) # (0, 1, 2, 0, 1, 2)

v = (0, 0.0, 0.0+0.0j, False) print(v) # (0, 0.0, 0j, False)

v = (1, 1.0, 1.0+0.0j, True) print(v) # (1, 1.0, (1+0j), True)

A tuple can have any types of elements as shown below:

v = ('A', b'A', bytearray(b'A'), 2, 2.3, 2.3+4.5j, True, [2, 3], (2, 3), {2, 3}, frozenset({2, 3}), {'A':'a'}, range(2, 3), iter([2, 3])) print(v) # ('A', b'A', bytearray(b'A'), 2, 2.3, (2.3+4.5j), True, # [2, 3], (2, 3), {2, 3}, frozenset({2, 3}), {'A': 'a'}, # range(2, 3), <list_iterator object at 0x000001F3B99BF250>)