Python 生成器说明

生成器

python 生成器

常规形态

# list
def square_numbers(nums: list):
    squared_nums = []
    for i in nums:
        squared_nums.append(i * i)
    return squared_nums

# demo
nums = [-1, 0, 1, 2, 3]
square_nums = square_numbers(nums)
list_nums = [i * i for i in nums]    # 列表推导式
print(square_nums)

generator

# generator
# 节省内存
# 只是生成一个生成器,未进行计算！！！
# 通过延迟加载的方式处理序列数据
def square_numbers(nums: list):
    for i in nums:
        yield(i * i)

# demo
nums = [-1, 0, 1, 2, 3]
square_nums = square_numbers(nums)
gen_nums = (i * i for i in nums)    # 生成器推导式
print(gen_nums)	# 生成器
# 全部生成
for num in square_nums:
    print(num)