First, list the type of built-in method

Role: Description multiple values, such as hobbies.
Definition: a plurality of any type can have the value of [], the elements separated by commas.
```
hobby_list = ['play', 'swimming', 'dancing']
my_friend = ['tbb','bill','tom']
```

Built-in methods: Priority to master, need to know.

3.1 Priority grasp

By index value (positive value + antiporter value), may be taken to storage.
```
my_friend = ['tbb','bill','tom']
my_friend[0] = 'TBB'
print(my_friend[0])
```
TBB

slice

my_friend = ['tbb','bill','tom']
print(my_friend[0::2])

['tbb', 'tom']

length

my_friend = ['tbb','bill','tom']
print(len(my_friend))

3

Members and not in operation in

my_friend = ['tbb','bill','tom']
print('Tbb' in my_friend)
print('frank' in my_friend)

False
True

Added value

my_friend = ['tbb','bill','tom']
my_friend.append('frank')
print(my_friend)

['tbb','bill','tom','frank']

delete

my_friend = ['tbb','bill','tom']
del my_friend[1]
print(my_friend)

['tbb','tom']

cycle

my_friend = ['tbb','bill','tom']
for name in my_friend:
    print(name)

tbb
bill
tom

3.2 need to know

insert () object into the specified position of the specified list.

my_friend = ['tbb','bill','tom']
my_friend.insert(1,'frank')
print(my_friend)

['tbb', 'frank', 'bill', 'tom']

2.pop () default to delete the last element

my_friend = ['tbb','bill','tom']
print(my_friend.pop(0))
print(my_friend)

tbb
['bill', 'tom']

remove () remove the first occurrence of a value in the list

my_friend = ['tbb','bill','tom','frank']
my_friend.remove('frank')
print(my_friend)

['tbb', 'bill', 'tom']

count () Count Occurrences

my_friend = ['tbb','bill','tom','frank']
print(my_friend.count('frank'))

1

index () Find index

my_friend = ['tbb','bill','tom','frank']
print(my_friend.index('tom'))

3

clear () Clears

my_friend = ['tbb','bill','tom','frank']
my_friend.clear()
print(my_friend)

[]

copy () Copy

my_friend = ['tbb','bill','tom','frank']
print(my_friend.copy())

['tbb', 'bill', 'tom', 'frank']

extend () a plurality of value added at the end of disposable another sequence list

my_friend = ['tbb','bill','tom','frank']
my_friend2 = ['byebye']
my_friend.extend(my_friend2)
print(my_friend)

['tbb', 'bill', 'tom', 'frank', 'byebye']

reverse () Reverse

my_friend = ['tbb','bill','tom','frank']
my_friend.reverse()
print(my_friend)

['frank', 'tom', 'bill', 'tbb']

sort () to sort the list of original

my_friend = ['tbb','bill','tom','frank']
my_friend.sort()
print(my_friend)

['bill', 'frank', 'tbb', 'tom']

Stored value or a plurality of values: a plurality of values

Ordered or disordered: Ordered

hobby_list = ['read', 'run', 'girl']
print(id(hobby_list))
hobby_list[2] = ''
print(id(hobby_list))

2352832078472
2352832078472

Variable or immutable: Variable Data Type

Second, the tuple type built-in method (Learn)

Tuples are immutable list, i.e., value tuples can not be changed, and therefore generally used only for only the tuple memory requirements are not taken. Thus tuples may also be substituted out list, so compared to the list of tuples used rarely. Tuple is a list of advantages compared to: modify the value list, the list structure will change, but only need to store tuples, in some extent, so the list require more memory. But now the industry is not a memory problem, so the industry group generally does not use Spring.

1. Role

Description multiple values, such as hobbies.

2. Definitions

In () may have a plurality of values of any type, a comma-separated elements

3. built-in method

1 index values

name_tuple = ('tbb', 'bill', 'tom', 'frank')
print(name_tuple[2])

tom

2 slices (care regardless of the end, step)

name_tuple = ('tbb', 'bill', 'tom', 'frank')
print(name_tuple[0:3:2])

('tbb', 'tom')

3 length

name_tuple = ('tbb', 'bill', 'tom', 'frank')
print(len(name_tuple))

4

4 members of the operation

name_tuple = ('tbb', 'bill', 'tom', 'frank')
print('tom' in name_tuple)

True

Cycle 5

name_tuple = ('tbb', 'bill', 'tom', 'frank')
for name in name_tuple:
    print(name)

tbb
bill
tom
frank

6count()

name_tuple = ('tbb', 'bill', 'tom', 'frank')
print(name_tuple.count('bill'))

1

7index()

name_tuple = ('tbb', 'bill', 'tom', 'frank')
print(name_tuple.index('tbb'))

0

4. The stored value or a plurality of values

A value

5. orderly or disorderly

Ordered

6. The variable or invariable

Immutable data type

7. The difference between tuples and lists of

Variable is a list of reasons: the memory address corresponding to the index value can be changed.
Tuples can not become the reason is: the index of the corresponding memory address values can not change, or conversely, as long as the memory address corresponding to the index value has not changed, then the tuple is never changed.

Third, the dictionary type built-in method

1. Role

A plurality of stored values, but each has a value of a corresponding key, key values described functions. It is used for different states when the stored value indicates, for example, the value stored there name, age, height, weight, hobbies.

2. Definitions

A plurality of elements separated by commas within {}, each element is key: value form, value can be any data type, but generally should be a string type key, but the key must be immutable.

3. built-in methods: Priority to master, need to know

3.1 Priority grasp

Access key press value: deposit may be desirable
```
dic = {'a': 1, 'b': 2}

print(dic['a'])
```
1

Length len

dic = {'a': 1, 'b': 2}

print(len(dic))

2

Members and not in operation in

dic = {'a': 1, 'b': 2}

print('a' in dic)
print(1 in dic)

True
False

del Delete

dic = {'a': 1, 'b': 2}
del dic['a']
print(dic)

{'b': 2}

dic = {'a': 1, 'b': 2}
dic.pop('a')
print(dic)

{'b': 2}

Keys Key (), the value of values (), on the key-value items () can return a list traversal (key, value) tuples array.

dic = {'a': 1, 'b': 2}
print(dic.keys())
print(dic.values())
print(dic.items())

dict_keys(['a', 'b'])
dict_values([1, 2])
dict_items([('a', 1), ('b', 2)])

cycle

dic = {'a': 1, 'b': 2}
for k, v in dic.items():  
    print(k, v)

a 1
b 2

3.2 need to know

get () Returns the value of the specified key, if the value is not in the dictionary returns the default value.
```
dic = {'a': 1, 'b': 2}
print(dic.get('a'))
print(dic.get('c'))
```
```
1
None
```
update () dict2 parameters of the dictionary key / value (key / value) updates the dictionary in dict
```
dic = {'a': 1, 'b': 2}
```
```
dic1 = {'a': 1, 'b': 2}
dic2 = {'c': 3}
dic1.update(dic2)
print(dic1)
```
{'a': 1, 'b': 2, 'c': 3}
fromkeys () is used to create a new dictionary, the sequence elements do seq dictionary key, value corresponding to all the keys to the dictionary initial value.
```
dic = dict.fromkeys(['name', 'age', 'sex'], None)
print(dic)
```
{'name': None, 'age': None, 'sex': None}

setdefault (): Similar to get (), if the key does not exist in the dictionary, it will add key and value to the default value

dic = {'a': 1, 'b': 2}
print(dic.setdefault('a',3))
print(dic)
print(dic.setdefault('c',3))
print(dic)

1
{'a': 1, 'b': 2}
3
{'a': 1, 'b': 2, 'c': 3}

4. The stored value or a plurality of values

A plurality of values, the value may be a plurality of types, key must be immutable type, generally should be immutable types string type

5. orderly or disorderly

Disorderly

6. The variable or invariable

Variable data types

dic = {'a': 1, 'b': 2}
print(id(dic))
dic['a'] = 3
print(id(dic))

2875759947640
2875759947640

Fourth, the set of built-in type method (set)

Collection can be understood as a collection of learning Python is a collection of students; students can learn Linux is a collection.

Features: 1 to 2 weight scrambled

1. Role

A lot of stuff storage elements, container data type

2. Definitions

{} The plurality of elements spaced apart by a comma, each element must be immutable.

s = {1, 2, 1, 'a'}  

print(s)

{1, 2, 'a'}

3. built-in methods: Priority to master, need to know

3.1 Priority grasp

Length len
```
s = {1, 2, 'a'}

print(len(s))
```
3
Members and not in operation in
```
s = {1, 2, 'a'}

print(1 in s)
```
True

| Union

pythoners = {'jason', 'nick', 'tank', 'sean'}
linuxers = {'nick', 'egon', 'kevin'}

print(pythoners|linuxers)
print(pythoners.union(linuxers))

{'egon', 'tank', 'kevin', 'jason', 'nick', 'sean'}
{'egon', 'tank', 'kevin', 'jason', 'nick', 'sean'}

& Intersection

pythoners = {'jason', 'nick', 'tank', 'sean'}
linuxers = {'nick', 'egon', 'kevin'}

print(pythoners&linuxers)
print(pythoners.intersection(linuxers))

nick
nick

- difference set

pythoners = {'jason', 'nick', 'tank', 'sean'}
linuxers = {'nick', 'egon', 'kevin'}
print(pythoners-linuxers)
print(pythoners.difference(linuxers))

{'tank', 'jason', 'sean'}
{'tank', 'jason', 'sean'}

^ Symmetric difference

pythoners = {'jason', 'nick', 'tank', 'sean'}
linuxers = {'nick', 'egon', 'kevin'}

print(pythoners^linuxers)
print(pythoners.symmetric_difference(linuxers))

pythoners = {'jason', 'nick', 'tank', 'sean'}
linuxers = {'nick', 'egon', 'kevin'}
javers = {'nick', 'egon', 'kevin'}

print(pythoners==linuxers)
print(javers==linuxers)

False
True

Parent Set:>,> =

pythoners = {'jason', 'nick', 'tank', 'sean'}
linuxers = {'nick', 'egon', 'kevin'}
javaers = {'jason', 'nick'}

print(pythoners>linuxers)
print(pythoners>=linuxers)
print(pythoners>=javaers)
print(pythoners.issuperset(javaers))

False
False
True
True

Subsets: <, <=

pythoners = {'jason', 'nick', 'tank', 'sean'}
linuxers = {'nick', 'egon', 'kevin'}
javaers = {'jason', 'nick'}

print(pythoners<linuxers)
print(pythoners<=linuxers)
print(javaers.issubset(javaers))

False
False
True

3.2 need to know

add()
```
s = {1, 2, 'a'}
s.add(3)

print(s)
```
{1, 2, 3, 'a'}
.remove()
```
s = {1, 2, 'a'}
s.remove(1)

print(s)
```
{2, 'a'}

difference_update () for removing the two sets of elements are present

pythoners = {'jason', 'nick', 'tank', 'sean'}
linuxers = {'nick', 'egon', 'kevin'}
pythoners.difference_update(linuxers)

print(pythoners)

{'tank', 'jason', 'sean'}

discard () for removing the specified collection element.

# set之discard()
s = {1, 2, 'a'}
# s.remove(3)  # 报错
s.discard(3)

print(s)

{1, 2, 'a'}

isdisjoint () for determining whether the two sets contain the same elements, if not returns True, otherwise return False.

pythoners = {'jason', 'nick', 'tank', 'sean'}
linuxers = {'nick', 'egon', 'kevin'}
pythoners.isdisjoint(linuxers)

print(pythoners.isdisjoint(linuxers))

False

4. The stored value or a plurality of values

A plurality of values, and is immutable.

5. orderly or disorderly

Disorderly

6. The variable or invariable

Variable data types

day 08 summary (built-in method)

First, list the type of built-in method

3.1 Priority grasp

3.2 need to know

Second, the tuple type built-in method (Learn)

1. Role

2. Definitions

3. built-in method

4. The stored value or a plurality of values

5. orderly or disorderly

6. The variable or invariable

7. The difference between tuples and lists of

Third, the dictionary type built-in method

1. Role

2. Definitions

3. built-in methods: Priority to master, need to know

3.1 Priority grasp

3.2 need to know

4. The stored value or a plurality of values

5. orderly or disorderly

6. The variable or invariable

Fourth, the set of built-in type method (set)

1. Role

2. Definitions

3. built-in methods: Priority to master, need to know

3.1 Priority grasp

3.2 need to know

4. The stored value or a plurality of values

5. orderly or disorderly

6. The variable or invariable

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