Python Set Method Summary

1. Add an item at the tail

Add (...)

This have no effect if the element is already present

>>> a = set ([1,2,3,4,5])

>>> A.add(' Shaw ')

>>> A

Set ([1, 2, 3, 4, 5, ' Shaw '])

2 . Empties all elements in the collection

Clear (...)

Remove all elements from the This set

>>>a = Set ([1, 2, 3, 4, 5, ' Shaw '])

>>>a.Clear()

>>>a

Set ([])

3. Returns a new collection, but the elements in the new collection, a has,b does not

Difference (...)

>>> a = set ([1, 2, 3, 4, 5, ' Shaw '])

>>> B = Set ([2,3,5, ' Sam '])

>>> A.difference(b)

Set ([1, 4, ' Shaw '])

4. Delete from set a , elements owned by both collection a and set b

Difference_update (...)

>>> a = set ([1, 2, 3, 4, 5, ' Shaw '])

>>> B = Set ([2,3,5, ' Sam '])

>>> A.difference_update(b)

>>> A

Set ([1, 4, ' Shaw '])

>>> b

Set ([2, 3, 5, ' Sam '])

5. Delete The specified element in the set (even if the element does not exist with this set, no error will be given)

Discard (...)

The Remove an element from a set if it is amember. f The element is not a member, does nothing.

>>> a = set ([1, 2, 3, 4, 5, ' Shaw '])

>>> A.Discard(' 5 ')

>>> A

Set ([1, 2, 3, 4, 5, ' Shaw '])

>>> A.discard (' Sam ')

>>> A

Set ([1, 2, 3, 4, 5, ' Shaw '])

6. Returns a new collection with a new collection element consisting of the intersection of set a and set B

Intersection (...)

Return the intersection of or more Setsas a new set.

>>> a = set ([1, 2, 3, 4, 5, ' Shaw '])

>>> B = Set ([2,3,5, ' Sam '])

>>> a.intersection (b) equivalent to A & B

Set ([2, 3, 5])

7. remove elements from set a thatare outside the intersection of a and b

Intersection_update (...)

>>> a = set ([1, 2, 3, 4, 5, ' Shaw '])

>>> B = Set ([2,3,5, ' Sam '])

>>> A.intersection_update (b)

>>> A

Set ([2, 3, 5])

8. Determine if two sets have intersections, and if so, return True, otherwise False

Isdisjoint (...)

>>> a = set ([1, 2, 3, 4, 5, ' Shaw '])

>>> B = Set ([2,3,5, ' Sam '])

>>> A.isdisjoint (b)

False

>>> C = Set ([9, ' alices '])

>>> A.isdisjoint (c)

True

9 . Tests whether the elements in one collection are in another element (that is, whether test set b is a subset of collection a )

Issubset (...)

Report whether another set contains the this set

Note:

Issuperset (...)

Report whether this set contains another set

>>> a = set ([1, 2, 3, 4, 5, ' Shaw '])

>>> B = Set ([2,3,5, ' Sam '])

>>> C = Set ([5, ' Shaw '])

>>> B.issubset (a)

False

>>> C.issubset (a) equivalent to C <= a

True

Delete an element (the first item is deleted by default) and if the element to be deleted does not exist, it is reported keyerror

Pop (...)

>>>a = Set ([1, 2, 3, 4, 5, ' Shaw '])

>>>a.pop ()

1

>>>a

Set ([2,3, 4, 5, ' Shaw '])

Delete the specified element, and if the element to be deleted does not exist, it is reported keyerror

Remove (...)

>>> a = set ([1, 2, 3, 4, 5, ' Shaw '])

>>> A.remove (1)

>>> A

Set ([2, 3, 4, 5, ' Shaw '])

>>> a.remove (' Shaw ')

>>> A

Set ([2, 3, 4, 5])

Symmetric difference set (this element is in a and not in b , and b has a elements not in the

Symmetric_difference (...)

>>> a = set (' ABCdef ')

>>> B = Set (' Abcklyt ')

>>> A.symmetric_difference (b)

Set ([' E ', ' t ', ' f ', ' y ', ' k ', ' l ', ' d '])

>>> a ^ b

Set ([' E ', ' t ', ' f ', ' y ', ' k ', ' l ', ' d '])

Take a set (returns a new set containing each element in s and t )

Union (...)

>>> a = set (' ACDF ')

>>> B = Set (' Adkh ')

>>> A.union (b)

Set ([' A ', ' C ', ' d ', ' f ', ' h ', ' K '])

>>> A | B

Set ([' A ', ' C ', ' d ', ' f ', ' h ', ' K '])

Add an element to collection a (when another collection is added, duplicate elements are removed)

Update (...)

>>> a = set (' ACDF ')

>>> B = Set (' Adkh ')

>>> A.update (b)

>>> A

Set ([' A ', ' C ', ' d ', ' f ', ' h ', ' K '])

>>> a = set (' ACDF ')

>>> B = Set (' Adkh ')

>>> a |= b

>>> A

Set ([' A ', ' C ', ' d ', ' f ', ' h ', ' K '])

>>> a= set (' Shaw ')

>>> a.update (' Bnga ')

>>> A

Set ([' A ', ' B ', ' g ', ' h ', ' n ', ' s ', ' W ')

This article is from the "Shaw blog" blog, please be sure to keep this source http://opsedu.blog.51cto.com/9265055/1762866

Python Set Method Summary