# Python 內建容器
###### tags: `Python` `Container`
#### 2022/04/01 by JohnAxer

- Python 內建容器 Container
- 容器顧名思義就是用來儲存物品的東西，而用來裝資料的就是資料容器。Python 內建有四大資料容器，好好利用，對於解決問題有莫大的幫助。
- 串列(list): ``a = [1,2,3,4]``
- 元組(tuple): ``t = (1,2,3,4)``
- 集合(set): ``s = {1,2,3,4}``
- 字典(dictionay): ``d = {"age":28, "name": "JohnAxer"}``

- 集合
- 使用範例

    #宣告或定義
    e1 = set()
    s1 = {1, 2, 5, 5, 8}
    s2 = { i**2 for i in range(5) }  # {0, 1, 4, 9, 16}
    print("e1 =", e1)
    print("s1 =", s1)
    print("s2 =", s2)

    #集合元素的增刪與巡覽
    s1.add(9)
    print("s1 =", s1)
    s1.remove(5)
    print("s1 =", s1)
    result = 16 in s2
    print("16 in s2 = ", result)
    for i in s2:
        print(i)

    #集合屬性 len、sum、max、min
    print("len =", len(s1))
    print("sum =", sum(s1))
    print("max =", max(s1))
    print("min =", min(s1))

    #集合運算
    #union
    s3 = s1 | s2
    print("s3 =", s3)

    #intersection
    s4 = s1 & s2
    print("s4 =", s4)

    #差集
    s5 = s1 - s2
    s6 = s2 - s1
    print("s5 =", s5)
    print("s6 =", s6)

    #對稱差集
    s7 = s1 ^ s2
    print("s7 =", s7)

    #轉型
    a = [1, 2, 3, 5, 5, 5, 10]
    s8 = set(a)    # {1, 2, 3, 5, 10}
    a = list(s8)   # [1, 2, 3, 5, 10]
    print(a)

- 集合中的元素本身是無序的且不重複的，所以，集合不能排序。

- 字典
- 範例

    #宣告
    d1 = {}      #空字典
    d2 = dict()  #空字典
    d3 = {
        "name": 'johnaxer',
        'age': 50,
        'height': 170,
        'weight': 72,
        'salary': [6, 7, 8, 6],
        5: "888"
    }

    #存取 Read
    print(d3['name'])
    #print(d3['sex'])   #error
    print(d3.get('sex'))

    #取得所有 key
    print(list(d3.keys()))

    #判斷有沒有這個 key
    print("sex" in d3.keys())
    print("age" in d3.keys())
    print("abc" in d3)

    #取出所有值
    print(list(d3.values()))
    a = list(d3.values())
    print(a[4][2])

    #新增 create
    d3["sex"] = "男"
    print(d3)

    #修改  update
    d3["sex"] = '女'
    print(d3)
    print(len(d3))

    #刪除  delete
    del d3["salary"]
    print(d3)

    sex = d3.pop("sex")
    print(d3)
    print(sex)

    d3.clear()
    print(d3)