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Jing Zhang
Courses Plus Student 6,465 PointsWhy I can change the element in a tuple??!!
my_third_tuple = ([1,2,3])
print(my_third_tuple)
>>> [1, 2, 3]
my_third_tuple[1] = 5
my_third_tuple
>>> [1, 5, 3]
what?!! I was expecting an error! I am using Jupyter Notebook py35
3 Answers
Jason Anello
Courses Plus Student 94,610 PointsYou could have created a 1 element tuple by adding a comma after the list.
However, if your tuple contains a list, you will still be able to change that list. What you can't do is change the reference to that list to be something else.
>>> my_tuple = ([1, 2, 3],)
>>> my_tuple
([1, 2, 3],)
>>> type(my_tuple)
<class 'tuple'>
>>> my_tuple[0][1] = 5
>>> my_tuple
([1, 5, 3],)
>>> my_tuple[0] = 5
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: 'tuple' object does not support item assignment
>>>
Seth Kroger
56,413 Points([1, 2, 3]) is an array. One way to look at is because it's only a single value, the "tuple" is collapsed to the value. If it was (1, 2, 3) it would be a 3-element tuple and it wouldn't change.
Jing Zhang
Courses Plus Student 6,465 PointsThank you! I am too careless. I created the tuple wrong. What I created are lists, instead of tuples.
Jason Anello
Courses Plus Student 94,610 PointsJason Anello
Courses Plus Student 94,610 Pointsfixed code formatting