python压缩映射过滤器

a=[1,2]

b=‘abcd’

c=zip(a,b)#压缩以短的为主

for x in c:

print(x)

def deal(b):

return b*b

a=[1,2,3,4]

c=map(deal,a)

print©

for i in c:

print(i)

a=[{‘name’:‘张三’,‘age’:18},

{‘name’:‘张二’,‘age’:28},

{‘name’:‘张大’,‘age’:38}

]

def maxage(a):

return a[‘age’]

c=max(a,key=maxage)

print©

def maxage(a):

return a[‘age’]

c=max(a,key=maxage)#以字典中的年龄作为参照

print©

def maxage(a):

return a[‘age’]#maxage=a[‘age’]

c=max(a,key=maxage)

print©

a=[1,3,-5,8,2]

a.sort()

print(a)

a.sort(key=abs)

print(a)

a=[2,5,-1,-6,3]

a.sort(key=abs)#abs绝对值abs,abs

print(a)

a=[2,4,-2,0,32]

a.sort(key=abs)

print(a)

def se(a):

return a%21

b=[1,2,3,4,5]

c=filter(se,b)#filter过滤器如果对就收入，如果错就抛弃

for i in c:

print(i)

def se(a):

return a%20

b=[1,2,3,4]

c=filter(se,b)

for i in c:

print(i)