Tuples of combined data types

describe

This is one about " Tuples of combined data types " My little exercises , Override the base of tuple types 、 The operator 、 Use of functions and methods, etc , There are two parts ： Follow practice and quiz .‪‬‪‬‪‬‪‬‪‬‮‬‭‬‫‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‪‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‭‬‪‬‪‬‪‬‪‬‪‬‮‬‭‬‫‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‭‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‪‬

stay " Follow practice " link , Please use IDLE The interaction mode of the editor , Enter the following statements one by one , Observe and compare the output .‪‬‪‬‪‬‪‬‪‬‮‬‭‬‫‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‪‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‭‬‪‬‪‬‪‬‪‬‪‬‮‬‭‬‫‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‭‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‪‬

stay " quiz " link , Please fill in the corresponding " Submission code " Enter the code on the page as required ," Save and submit comments " Check the results after .‪‬‪‬‪‬‪‬‪‬‮‬‭‬‫‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‪‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‭‬‪‬‪‬‪‬‪‬‪‬‮‬‭‬‫‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‭‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‪‬

Follow practice

  Please use IDLE The interaction mode of the editor （ contain >>> Prompt ）, Enter the following statements one by one in order （ common 20 individual ）：‪‬‪‬‪‬‪‬‪‬‮‬‭‬‫‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‪‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‭‬‪‬‪‬‪‬‪‬‪‬‮‬‭‬‫‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‭‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‪‬

>>>t = 1, 2, 3, 2, 1
>>>max(t)
3
>>>t.index(1)
0
>>>t.count(1)
2
>>>s = (1, "a", 2, "b")
>>>min(s)
Traceback (most recent call last):
  File "<pyshell#49>", line 1, in <module>
    min(s)
TypeError: unorderable types: str() < int()
>>>t + s
(1, 2, 3, 2, 1, 1, 'a', 2, 'b')
>>>print(t, s)
(1, 2, 3, 2, 1) (1, 'a', 2, 'b')
>>>t2 = tuple(set(t))
>>>print(t, t2)
(1, 2, 3, 2, 1) (1, 2, 3)
>>>len(t)
5
>>>t > t2
True
>>>t3 = t2*3
>>>print(t2, t3)
(1, 2, 3) (1, 2, 3, 1, 2, 3, 1, 2, 3)
>>>t3[::3]
(1, 1, 1)
>>>t3[::-1]
(3, 2, 1, 3, 2, 1, 3, 2, 1)
>>>t2 in t3
False
>>>2, 3 in t3
(2, True)
>>>p = 1, 2, [1,2]
(1, 2, [1, 2])
>>> p[-1]
[1, 2]

quiz

Please paste the following code into " Submission code " page ," Save and submit comments " Check the results after . Be careful , At this point, the code is not in interactive mode , It's file mode . ‪‬‪‬‪‬‪‬‪‬‮‬‭‬‫‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‪‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‭‬‪‬‪‬‪‬‪‬‪‬‮‬‭‬‫‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‭‬‪‬‪‬‪‬‪‬‪‬‮‬‫‬‪‬

t = 1, 2, 3, [1, 2, 3]
try:
   t[-1].extend([4, 5, 6])
   print(t)
except:
   print("error")

When defining tuples , A list can be its element , In fact, the pointer to the list is its element . therefore , Tuples require that their elements cannot be modified , As long as the list pointer is not modified . therefore , Here we see a kind of " strange " The phenomenon of , Of a tuple element " value " Can be modified , Please understand this phenomenon reasonably .