python练习题-day13

1.获取移动平均值

def wrapper(fun):
    def inner(*args,**kwargs):
        ret=fun(*args,**kwargs)
        ret.__next__()
        return ret
    return inner
@wrapper
def g():
    sum=0
    count=0
    avg=0
    while True:
        num=yield avg
        sum+=num
        count+=1
        avg=sum/count
f=g()
print(f.send(10))
print(f.send(20))
print(f.send(30))

2.处理文件：用户指定要查找的文件和内容
将文件中包含要查找内容的每一行都输出到屏幕

def search():
    with open("a1.txt",encoding="utf-8") as f1:
        for i in f1:
            if "我" in i:
                yield i
g=search()
for i in g:
    print(i.strip())

3.写生成器，从文件中读取内容，在每一次读取到的内容之前加上‘***’之后再返回用户

def file_add():
    with open("a1.txt",encoding="utf-8") as f1:
        for i in f1:
            yield "***"+i
g=file_add()
for i in g:
    print(i.strip())

4.面试题

def demo():
    for i in range(4):
        yield i

g=demo()

g1=(i for i in g)
g2=(i for i in g1)

print(list(g1))
print(list(g2))

面试题1

def add(n,i):
    return n+i

def test():
    for i in range(4):
        yield i

g=test()
for n in [1,10]:
    g=(add(n,i) for i in g)

print(list(g))

import os

def init(func):
    def wrapper(*args,**kwargs):
        g=func(*args,**kwargs)
        next(g)
        return g
    return wrapper

@init
def list_files(target):
    while 1:
        dir_to_search=yield
        for top_dir,dir,files in os.walk(dir_to_search):
            for file in files:
                target.send(os.path.join(top_dir,file))
@init
def opener(target):
    while 1:
        file=yield
        fn=open(file)
        target.send((file,fn))
@init
def cat(target):
    while 1:
        file,fn=yield
        for line in fn:
            target.send((file,line))

@init
def grep(pattern,target):
    while 1:
        file,line=yield
        if pattern in line:
            target.send(file)
@init
def printer():
    while 1:
        file=yield
        if file:
            print(file)

g=list_files(opener(cat(grep('python',printer()))))

g.send('/test1')

协程应用：grep -rl /dir

tail&grep