第四章 列表,切片,元组
1 # 第四章 操作列表 2 3 magicians = ['alice', 'david', 'carolina'] 4 for magician in magicians: 5 print(magician) 6 7 for magician in magicians: 8 print(magician.title() + ",that was a great trick!") 9 print("循环内语句,前面有空格缩进") 10 11 for magician in magicians: 12 print(magician.title() + ",that was a great trick!") 13 print("循环外语句") 14 15 # 创建数字列表 只有1,2,3,4 没有5,5是开区间 16 # start是闭区间 end是开区间 17 for value in range(1, 5): 18 print(value) 19 20 # 转list列表 [1, 2, 3, 4, 5] 21 numbers = list(range(1, 6)) 22 print(numbers) 23 24 # 指定步长的list [2, 4, 6, 8, 10] 25 even_numbers = list(range(2, 11, 2)) 26 print(even_numbers) 27 28 # [1, 4, 9, 16, 25, 36, 49, 64, 81, 100] 29 squares = [] 30 for value in range(1, 11): 31 squares.append(value ** 2) 32 print(squares) 33 34 # 上面等价于一行代码 35 squares = [value ** 2 for value in range(1, 11)] 36 print(squares) 37 38 # 列表的统计 39 digits = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0] 40 print(min(digits)) 41 print(max(digits)) 42 print(sum(digits)) 43 44 # 切片 有点像substring 45 players = ['charles', 'martina', 'michael', 'florence', 'eli'] 46 # ['charles', 'martina', 'michael'] 47 print(players[0:3]) 48 # ['martina', 'michael', 'florence'] 49 print(players[1:4]) 50 # ['charles', 'martina', 'michael', 'florence'] 51 print(players[:4]) 52 # ['michael', 'florence', 'eli'] 53 print(players[2:]) 54 # 最后3名队员的名字 55 # ['michael', 'florence', 'eli'] 56 print(players[-3:]) 57 58 # 遍历切片 前3名队员 59 for play in players[:3]: 60 print(play.title()) 61 62 # 复制列表 值拷贝 63 my_foods = ['pizza','falafel','carrot cake'] 64 friend_foods = my_foods[:] 65 print("my favorite foods are:") 66 print(my_foods) 67 print("my friend favorite foods are:") 68 print(friend_foods) 69 70 # 引用 71 friend_foods = my_foods 72 73 #元组 74 dimensions = (200,50) 75 print(dimensions[0]) 76 print(dimensions[1]) 77 #修改值禁止 78 #dimension[0]=250 79 80 # 遍历元组 81 for dimension in dimensions: 82 print(dimension) 83 84 # 修改元组值 85 dimensions = (200,50) 86 dimensions = (400,100) 87 for dimension in dimensions: 88 print(dimension)