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  • 匿名函数

    #匿名函数
    def cal(n):
    return n*n

    #匿名函数 简单的需要用函数去解决的问题 匿名函数的函数体 只有一行
    #也叫lambda表达式
    # cal2 = lambda n : n*n
    # ret = cal2(20)
    # print(ret)

    # def add(x,y):return x+y
    # add2 = lambda x,y : x+y
    # ret = add2(1,2)
    # print(ret)

    dic={'k1':10,'k2':100,'k3':30}

    # print(max(dic))
    # func = lambda k:dic[k]
    # print(max(dic,key = func))
    # print(max(dic,key = lambda k:dic[k]))

    l = [1,2,3,4]
    # def pow2(x):
    # return x*x
    # map(pow2,l)
    # print(list(map(lambda x:x*x , l)))

    l = [10,11,8,12]
    # def func(x):
    # return x>10
    # print(list(filter(func,l)))
    # print(list(filter(lambda x:x>10,l)))

    #现有两个元组(('a'),('b')),(('c'),('d')),请使用python中匿名函数生成列表[{'a':'c'},{'b':'d'}]
    t1 = (('a'),('b'))
    t2 = (('c'),('d'))

    # print(list(zip(t1,t2)))
    # print(list(map(lambda t:{t[0]:t[1]} ,zip(t1,t2))))
    # print([{i:j} for i,j in zip(t1,t2)]) #item = ('a', 'c') i,j = ('a', 'c')
    # func = lambda t1,t2 : [{i:j} for i,j in zip(t1,t2)]
    # ret = func(t1,t2)
    # print(ret)
    # print(len([ i+5 for i in range(100) if i % 3 == 0 ]))
    # new_l = []
    # for i in range(100):
    # if i%3 == 0:
    # new_l.append(i+5)
    #
    # print(len([i//2 if i%2==0 else i for i in range(100) if i % 3 == 0 ]))
    #
    # for i in range(100):
    # if i % 3 == 0:
    # if i%2 == 0:
    # new_l.append(i//2)
    # else:
    # new_l.append(i)

    print([i for i in range(30) if i%3 == 0])
    print([i*i for i in range(30) if i%3 == 0])

    # names = [['Tom', 'Billy', 'Jefferson', 'Andrew', 'Wesley', 'Steven', 'Joe'],
    # ['Alice', 'Jill', 'Ana', 'Wendy', 'Jennifer', 'Sherry', 'Eva']]
    # print([name for lst in names for name in lst if name.count('e') >=2])

    mcase = {'a': 10, 'b': 34}
    # for i in mcase:
    # print(i)

    # [i for i in mcase]
    # print({key:key+'1' for key in mcase})
    # print({key:mcase[key] for key in mcase})
    # print({mcase[key]:key for key in mcase})

    # mcase = {'a': 10, 'b': 34, 'A': 7, 'Z': 3}
    # mcase_frequency = {k.lower(): mcase.get(k.lower(), 0) + mcase.get(k.upper(), 0) for k in mcase}
    # print(mcase_frequency)

    # l = [-1,1,2,1]
    # print({i for i in l})
    # print({i*i for i in l})
    print(123)
    m = input('>>')
    print(m)

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  • 原文地址:https://www.cnblogs.com/kxllong/p/7302414.html
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