Python first day-Getting Started Python (5) Collection operations

This article focuses on some simple operations for collections

Sets are divided into mutable sets and immutable sets

Variable set (non-hash)

S={1,'a', (+/-),}  # equals set ({1, ' a ', (+/-),})

Add Value

S={1,'a', (All-you-do),}print(s) s.add ('123 ' )print(s)

Clear Collection

S={1,'a', (+/-),}print(s) s.clear ()  Print(s)

Copy Collection

S={1,'a', (A/b),}print(s) a=s.copy ()Print (a)

Random Delete

S={1,'a', (+/-),}print(s) s.pop ()Print (s)

Specify delete element

S={1,'a', (A/b),}print(s) s.remove (1)Print (s)

Non-repeatable properties

Immutable collections

Less use

Calling the Frozenset method

F=frozenset ({1,2,3,4})

When you're done, you'll find no F.add,f.pop,f.remove method.

Variable Collection Common operations

Example:
python_list=['Tom','Jack','Lucy']openstact_list=['Rose','Tom','xiaoming','Lucy']p_u=Set (python_list) O_u=set (Openstact_list)#define a list as a collection

Subtraction

# learn only OpenStack courses without learning python lessons, and vice versa Res=o_u- p_uprint(res)

and set:

Res=p_u | O_u Print (RES)

Intersection:

Res=p_u & O_uprint(res)

Complementary set:

Res=p_u ^ O_uprint(res)

Parameter operation:

Print (P_u.difference (O_u))  # Straight Results p_u.difference_update (O_u)# Find the results and update print(P_u)

P_u.discard ('Tom')  # If the collection is removed, nothing is done print(P_u) P_u.discard ('asdasdasd')print(P_u)

Print (P_u.intersection (O_u))      # intersection # Output and update

Res=p_u.union (O_u)  # and set print(res)

# Cross complement set Print (RES)

Python first day-Getting Started Python (5) Collection operations