python基础知识-集合[set]方法操作

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}

# 将元素 10 添加到集合中
a.add(10)
print(a)

# 运行结果
{1, 2, 3, 4, 5, 6, 10}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}

# 从集合中移除元素 1。如果 1 不存在于集合中则会引发 KeyError
a.remove(1)
print(a)

# 运行结果
{2, 3, 4, 5, 6}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}

# 从集合中移除并返回任意一个元素。如果集合为空则会引发 KeyError
a.pop()
print(a)

# 运行结果
{2, 3, 4, 5, 6}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}
# 从集合中移除所有元素
a.clear()
print(a)

# 运行结果
set()

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}


# 返回原集合的浅拷贝
c = a.copy()
print(c)

# 运行结果
{1, 2, 3, 4, 5, 6}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}


# 更新集合，添加来自 b 中的所有元素
a.update(b)
print(a)

# 运行结果
{1, 2, 3, 4, 5, 6, 7, 8, 9}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}

# 如果集合中没有与 b 共有的元素则返回 True。当且仅当两个集合的交集为空集合时，两者为不相交集合
c = a.isdisjoint(b)
print(c)

# 运行结果
False

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}
b = {4, 5, 6, 7, 8, 9}


# 检测是否集合中的每个元素都在 b 之中
c = a.issubset(b)
print(c)

# 运行结果
False

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}


# 检测是否 b 中的每个元素都在集合之中
c = a.issuperset(b)
print(c)

# 运行结果
False

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}


# 返回一个新集合，其中包含来自原集合以及 b 指定的所有集合中的元素
c = a.union(b)
print(c)

# 运行结果
{1, 2, 3, 4, 5, 6, 7, 8, 9}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}


# 返回一个新集合，其中包含原集合以及 b 指定的所有集合中共有的元素
c = a.intersection(b)
print(c)

# 运行结果
{4, 5, 6}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}


# 返回一个新集合，其中包含原集合中在 b 指定的其他集合中不存在的元素
c = a.difference(b)
print(c)

# 运行结果
{1, 2, 3}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}


# 返回一个新集合，其中的元素或属于原集合或属于 b 指定的其他集合，但不能同时属于两者
c = a.symmetric_difference(b)
print(c)

# 运行结果
{1, 2, 3, 7, 8, 9}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}


# 更新集合，只保留其中在所有 b 中也存在的元素
a.intersection_update(b)
print(a)

# 运行结果
{4, 5, 6}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}


# 更新集合，移除其中也存在于 b 中的元素。
a.difference_update(b)
print(a)

# 运行结果
{1, 2, 3}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}


# 更新集合，只保留存在于集合的一方而非共同存在的元素
a.symmetric_difference_update(b)
print(a)

# 运行结果
{1, 2, 3, 7, 8, 9}

Process finished with exit code 0

a = {1, 2, 3, 4, 5, 6}

b = {4, 5, 6, 7, 8, 9}

# 如果元素 1 存在于集合中则将其移除。不存在就返回原集合
a.discard(1)
print(a)

# 运行结果
{2, 3, 4, 5, 6}

Process finished with exit code 0