【Python組み込み型】「set」のサンプルコード

Python
2022.09.09

こちらは「set」（Python組み込み型）のサンプルコードについての記事となっております。

基本情報 … Basic Information

Pythonの「set」は、重複しない要素の集合を表現するデータ型です。通常、波括弧 {} を用いて要素を定義します。

setは順序が保証されていないので、インデックスを指定して要素を取り出すことはできません。また、要素の変更も削除も可能ですが、変更することはできません。ただし、要素の追加や削除を行うことができます。

setは、集合演算（和集合、積集合、差集合など）を行う際に非常に便利です。また、データの重複を排除したい場合や、順序を気にせず要素を扱いたい場合にもよく利用されます。

チートシート … Cheat Sheet

Create a Empty Seta = set()set()
Create a Number Seta = {1,2,3}
Create a String Seta = {“one”,”two”,”three”}
Delete a Setdel a
Get a Length of the Seta=len(input_set)A. set()
B, {1,2,3}		A. 0
B. 3
Get a Type of the Seta=type(input_set)A. set()
B, {1,2,3}		A. <class ‘set’>
B. <class ‘set’>
Edit a Set with Valueinput_set.add(new_val)A. set(), 999
B. {1,2,3}, 999
C. {“one”,”two”,”three”}, 999		A. {999}
B. {1, 2, 3, 999}
C. {“one”,”two”,”three”,999}
Delete Elements of Setinput_set.clear()A. {1,2,3}
B. {“one”,”two”,”three”}		A. set()
B. set()
Create a Set with Set
Copy a Set		a = input_set.copy()A. {1,2,3}
B. {“one”,”two”,”three”}		A. {1,2,3}
B. {“one”,”two”,”three”}
Create a Set with Set
Difference		a = src_set.difference(dst_set)A. {1,2,3}, {2,4,6}
B. {2,4,6}, {1,2,3}		A. {1, 3}
B. {4, 6}
Create a Set with Set
Interaction		a = src_set.interaction(dst_set)A. {1,2,3}, {2,4,6}
B. {2,4,6}, {1,2,3}		A. {2}
B. {2}
Create a Set with Set
Symmetric Diffference		a = src_set.symmetric_difference(dst_set)A. {1,2,3}, {2,4,6}
B. {2,4,6}, {1,2,3}		A. {1, 3, 4, 6}
B. {1, 3, 4, 6}
Create a Set with Set
Union		a = src_set.union(dst_set)
a = src_set.union(dst_set1, dst_set2, …)		A. {1,2,3}, {4,5,6}
B. {1,2,3}, {2,4,6}
C. {1,2,3}, {4,5,6},{2,4,6}		A. {1, 2, 3, 4, 5, 6}
B. {1, 2, 3, 4, 6}
C. {1, 2, 3, 4, 5, 6}
Edit a Set with Set
Difference		src_set.difference_update(dst_set)A. {1,2,3}, {2,4,6}
B. {2,4,6}, {1,2,3}		A. {1, 3}
B. {4, 6}
Edit a Set with Set
Interaction		src_set.interaction_update(dst_set)A. {1,2,3}, {2,4,6}
B. {2,4,6}, {1,2,3}		A. {2}
B. {2}
Edit a Set with Set
Symmetric Diffference		src_set.symmetric_difference_update(dst_set)A. {1,2,3}, {2,4,6}
B. {2,4,6}, {1,2,3}		A. {1, 3, 4, 6}
B. {1, 3, 4, 6}
Edit a Set with Set
Union		src_set.update(dst_set)
src_set.update(dst_set1, dst_set2, …)		A. {1,2,3}, {4,5,6}
B. {1,2,3}, {2,4,6}
C. {1,2,3}, {4,5,6},{2,4,6}		A. {1, 2, 3, 4, 5, 6}
B. {1, 2, 3, 4, 6}
C. {1, 2, 3, 4, 5, 6}
Edit a Set with Value
Remove a Element of Set		input_set.discard(target_val)A. {1,2,3}, 2
B. {1,2,3}, 999		A. {1,3}
B. {1,2,3}
Edit a Set with Value
Remove a Element of Set		input_set.remove(target_val)
* KeyError		A. {1,2,3}, 2
B. {1,2,3}, 999		A. {1,3}
B. KeyError
Edit a Set
Pop a Element from Set		input_set.pop()
*KeyError:		A. {1,2,3}
B. {1}
C. set()		A. {2,3}
B. set()
C. KeyError
Check a Set with Set
Disjoint Checker		src_set.isdisjoint(dst_set)A. {1,2,3}, {4,5,6}
B. {1,2,3}, {2,4,6}		A.True
B. False
Check a Set with Set
Subset Checker		src_set.issubset(dst_set)A. {1,2,3}, {1,2,3,4,5,6}
B. {1,2,3,4,5,6}, {1,2,3}		A.True
B. False
Check a Set with Set
Superset Checker		src_set.issuperset(dst_set)A. {1,2,3}, {1,2,3,4,5,6}
B. {1,2,3,4,5,6}, {1,2,3}		A.True
B. False

サンプルコード … Sample Code

### Create Set
EMPTY_SET   = {}                        ### set()
INT_SET     = {1,2,3}
STR_SET     = ["one","two","three"]

### Delete Set
### del set
INT_SET     = {1,2,3}
del INT_SET

### Read Length
### len(set)
INT_SET     = {1,2,3}
### print(INT_SET)          ### {1, 2, 3}
### print(len(INT_SET))     ### 3

### Read Type
### type(set)
INT_SET     = {1,2,3}
### print(INT_SET)          ### {1, 2, 3}  
### print(type(INT_SET))    ### <class 'set'>

### Add new_val
### set.add(new_val)
INT_SET     = {1,2,3}
### print(INT_SET)          ### {1, 2, 3}  
INT_SET.add(999)
### print(INT_SET)          ### {1, 2, 3, 999}

### Clear All Values
### set.clear()
INT_SET     = {1,2,3}
### print(INT_SET)          ### {1, 2, 3}  
INT_SET.clear()
### print(INT_SET)          ### set()

### Create Copy
### set.copy()
INT_SET     = {1,2,3}
copy_SET_1  = INT_SET 
copy_SET_2  = INT_SET.copy()
### print(copy_SET_1)       ### {1, 2, 3}
### print(copy_SET_2)       ### {1, 2, 3}
INT_SET.add(999)
### print(copy_SET_1)       ### {1, 2, 999}
### print(copy_SET_2)       ### {1, 2, 3}

### Create Set (Difference)
INT_SET_1   = {1,2,3}
INT_SET_2   = {2,4,6}
diff_SET_1  = INT_SET_1.difference(INT_SET_2)
diff_SET_2  = INT_SET_2.difference(INT_SET_1)
### print(diff_SET_1)       ### {1, 3}
### print(diff_SET_2)       ### {4, 6}

### Create Set (Intersection)
INT_SET_1       = {1,2,3}
INT_SET_2       = {2,4,6}
inter_SET_1     = INT_SET_1.intersection(INT_SET_2)
inter_SET_2     = INT_SET_2.intersection(INT_SET_1)
### print(inter_SET_1)       ### {2}
### print(inter_SET_2)       ### {2}

### Create Set (Symmetric Difference)
INT_SET_1       = {1,2,3}
INT_SET_2       = {2,4,6}
sym_SET_1       = INT_SET_1.symmetric_difference(INT_SET_2)
sym_SET_2       = INT_SET_2.symmetric_difference(INT_SET_1)
### print(sym_SET_1)       ### {1, 3, 4, 6}
### print(sym_SET_2)       ### {1, 3, 4, 6}

### Create Set (Union)
INT_SET_1   = {1,2,3}
INT_SET_2   = {4,5,6}
INT_SET_3   = {2,4,6}

uni_SET_1 = INT_SET_1.union(INT_SET_2)
uni_SET_2 = INT_SET_1.union(INT_SET_3)
uni_SET_3 = INT_SET_1.union(INT_SET_2,INT_SET_3)

### print(uni_SET_1)        ### {1, 2, 3, 4, 5, 6}
### print(uni_SET_2)        ### {1, 2, 3, 4, 6}
### print(uni_SET_3)        ### {1, 2, 3, 4, 5, 6}

### Update Set (Difference)
INT_SET_1   = {1,2,3}
INT_SET_2   = {2,4,6}
### print(INT_SET_1)        ### {1, 2, 3}
### print(INT_SET_2)        ### {2, 4, 6}
INT_SET_1.difference_update(INT_SET_2)
### print(INT_SET_1)        ### {1, 3}

INT_SET_1   = {1,2,3}
INT_SET_2   = {2,4,6}
### print(INT_SET_1)        ### {1, 2, 3}
### print(INT_SET_2)        ### {2, 4, 6}
INT_SET_2.difference_update(INT_SET_1)
### print(INT_SET_2)        ### {4, 6}

### Update Set (Intersection)
INT_SET_1   = {1,2,3}
INT_SET_2   = {2,4,6}
### print(INT_SET_1)        ### {1, 2, 3}
### print(INT_SET_2)        ### {2, 4, 6}
INT_SET_1.intersection_update(INT_SET_2)
### print(INT_SET_1)        ### {2}

INT_SET_1   = {1,2,3}
INT_SET_2   = {2,4,6}
### print(INT_SET_1)        ### {1, 2, 3}
### print(INT_SET_2)        ### {2, 4, 6}
INT_SET_2.intersection_update(INT_SET_1)
### print(INT_SET_2)        ### {2}

### Update Set (Symmetric Difference)
INT_SET_1   = {1,2,3}
INT_SET_2   = {2,4,6}
### print(INT_SET_1)        ### {1, 2, 3}
### print(INT_SET_2)        ### {2, 4, 6}
INT_SET_1.symmetric_difference_update(INT_SET_2)
### print(INT_SET_1)        ### {1, 3, 4, 6}

INT_SET_1   = {1,2,3}
INT_SET_2   = {2,4,6}
### print(INT_SET_1)        ### {1, 2, 3}
### print(INT_SET_2)        ### {2, 4, 6}
INT_SET_2.symmetric_difference_update(INT_SET_1)
### print(INT_SET_2)        ### {1, 3, 4, 6}

### Update Set (Union)
INT_SET_1   = {1,2,3}
INT_SET_2   = {2,4,6}
### print(INT_SET_1)        ### {1, 2, 3}
### print(INT_SET_2)        ### {2, 4, 6}
INT_SET_1.update(INT_SET_2)
### print(INT_SET_1)        ### {1, 2, 3, 4, 6}

INT_SET_1   = {1,2,3}
INT_SET_2   = {2,4,6}
### print(INT_SET_1)        ### {1, 2, 3}
### print(INT_SET_2)        ### {2, 4, 6}
INT_SET_2.update(INT_SET_1)
### print(INT_SET_2)        ### {1, 2, 3, 4, 6}

### Remove target_val
INT_SET     = {1,2,3}
### print(INT_SET)          ### {1, 2, 3}
INT_SET.discard(2)
INT_SET.discard(999)
### print(INT_SET)          ### {1, 3}

### Remove target_val
INT_SET     = {1,2,3}
### print(INT_SET)          ### {1, 2, 3}
INT_SET.remove(2)
### print(INT_SET)          ### {1, 3}
### INT_SET.remove(999)     ### KeyError: 999

### Remove Random Value
INT_SET     = {1,2,3}
### print(INT_SET)          ### {1, 2, 3}
INT_SET.pop()
### print(INT_SET)          ### {2, 3}
INT_SET.pop()
### print(INT_SET)          ### {3}

### Check Disjoint
INT_SET_1   = {1,2,3}
INT_SET_2   = {4,5,6}
INT_SET_3   = {2,4,6}

### print(INT_SET_1.isdisjoint(INT_SET_2))  ### True
### print(INT_SET_1.isdisjoint(INT_SET_3))  ### False

### Check Subset
INT_SET_1   = {1,2,3}
INT_SET_2   = {1,2,3,4,5,6}

### print(INT_SET_1.issubset(INT_SET_2))    ### True
### print(INT_SET_2.issubset(INT_SET_1))    ### False

### Check Superset
INT_SET_1   = {1,2,3}
INT_SET_2   = {1,2,3,4,5,6}

### print(INT_SET_1.issuperset(INT_SET_2))  ### False
### print(INT_SET_2.issuperset(INT_SET_1))  ### True

このプログラムは、Pythonのセット(set)に関する基本的な操作を紹介しています。プログラム内で行われている操作には、セットの作成、削除、長さの取得、タイプの取得、値の追加、値の削除、コピーの作成、差分の取得、共通部分の取得、対象差分の取得、和集合の取得、差分のアップデート、共通部分のアップデート、対象差分のアップデート、和集合のアップデート、ランダムな値の削除、部分集合の確認、上位集合の確認などが含まれます。

参考リンク … Reference Link

Built-in Types
The following sections describe the standard types that are built into the interpreter. The principal built-in types are...
docs.python.org
Sets in Python - GeeksforGeeks
A Computer Science portal for geeks. It contains well written, well thought and well explained computer science and prog...
www.geeksforgeeks.org
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