匿名函数 - lambda 的应用
lambda 的高级应用：
1 # ---CASE 1 2 fs = map(lambda i:(lambda j: i*j), range(6)) 3 print([f(2) for f in fs]) 4 5 #---CASE 2 6 fs = [lambda j:i*j for i in range(6)] 7 print([f(2) for f in fs]) 8 9 #---CASE 3 10 fs = [] 11 for i in range(6): 12 fs.append(lambda j:i*j) 13 if i==3: 14 break 15 print([f(2) for f in fs]) 16 17 #---CASE 4 18 fs = [(lambda i:lambda j:i*j)(i) for i in range(6)] 19 print([f(2) for f in fs])
[0, 2, 4, 6, 8, 10]
[10, 10, 10, 10, 10, 10]
[6, 6, 6, 6]
[0, 2, 4, 6, 8, 10]
参考：www.cnblogs.com/xiangnan/p/3900285.html?utm_source=tuicool&utm_medium=referral
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>>> L = [['a',1],['a',2],['a',4],['b',1],['b',2]];
>>> L
[['a', 1], ['a', 2], ['a', 4], ['b', 1], ['b', 2]]
>>> {key:[k[1] for k in L if k[0]==key] for key in set(j[0] for j in L)}
{'a': [1, 2, 4], 'b': [1, 2]}
