python进阶日记（生成器）

list1 = [x*3 for x in range(10)]
print(type(list1))

g = (x*3 for x in range(10))
print(type(g))

print(next(g))

用生成器的好处在于不用一次开辟所有空间，每次去数子再运算即可

def fib(length):
    a, b = 0, 1
    n = 0
    while n < length:
        a, b = b, a + b
        n += 1
        yield b  #可以近似理解为return b
        

g = fib(100)
print(g) #得到的是一个生成器
print(next(g))
print(next(g))
print(next(g))
print(next(g))
print(next(g))
print(next(g))
print(next(g))
print(next(g))

生成器用于多线程：

def thread1():
    for i in range(10):
        yield None
        print("--{}--".format(i))

def thread2():
    for i in range(10):
        yield None
        print("++{}++".format(i))


g1 = thread1()
g2 = thread2()

while True:
    try:
        for i in range(10): #用生成器来实现交替进行函数
            next(g1)
            next(g2)
    except:
        break