python学习---列表生成式
1 #!/usr/bin/env python3 2 # -*- coding: utf-8 -*- 3 4 #列表生成式即List Comprehensions,是Python内置的非常简单却 5 #强大的可以用来创建list的生成式 6 print([x * x for x in range(1,21,2)]) 7 print([x * x for x in range(1,11) if x % 2 == 0]) 8 print([m + n for m in 'ABC' for n in 'XYZ']) 9 10 d = {'x': 'A', 'y': 'B', 'z': 'C'} 11 print([k + '=' + v for k,v in d.items()]) 12 13 L = ['Hello', 'World', 'IBM', 'Apple'] 14 print([s.lower() for s in L]) 15 16 L2 = ['Hello', 'World', 18, 'IBM', 'Apple'] 17 def lower2(s): 18 if isinstance(s,str): 19 return s 20 else: 21 return s 22 print([lower2(s) for s in L2])