Sometimes how we do not want a list of data to be modified people? You can use a tuple store, tuples also known as read-only list, can not be modified.
Definition: list-like, but [] into ()
characteristic:
1 can store a plurality of values
2. immutable
3. defines tuple element order from left to right, starting from index 0 accessed sequentially and orderly
create
1 ages = (11, 22, 33, 44, 55) 2 3 #或 4 5 ages = tuple((11, 22, 33, 44, 55))
Common Operations
1 # index 2 >>> AGEs = (. 11, 22 is, 33 is, 44 is, 55 ) . 3 >>> AGEs [0] . 4 . 11 . 5 >>> AGEs [. 3 ] . 6 44 is . 7 >>> AGEs [-1 ] . 8 55 . 9 # slice: List with 10 # cycles . 11 >>> for Age in AGEs: 12 is Print (Age) 13 is . 11 14 22 is 15 33 is 16 44 is . 17 55 18 is # length 19 >>> len(ages) 20 5 21 #包含 22 >>> 11 in ages 23 True 24 >>> 66 in ages 25 False 26 >>> 11 not in ages 27 False
Note: tuples immutable itself, if the tuple further includes other variable elements, these variable elements may vary
why? Since tuples just the address of each memory storage element, [ 'Wangyou Hu', 'Jack'] of this list itself presence tuple memory address does not change, but the list contains the memory address of an element is the presence of additional space It is variable.