Python數據基礎類型-新建列表

1，遍歷列表

　　遍歷列表的全部元素，對每一個元素執行相同的操做。可以使用for循環

magicians = ['alice','david','carolina']
for magician in magicians:
　　print(magician)

運行結果
alice
david
carolina

magicians = ['alice','david','carolina']
for magician in magicians:
    #print(magician)
    print(magician.title() + ", that was a great trick!")
    print("I can't wait to see your next trick, " + magician.title() + ".\n")

print("Thank you, everyone. That was a great magic show!")

運行結果
Alice, that was a great trick!
I can't wait to see your next trick, Alice.

David, that was a great trick!
I can't wait to see your next trick, David.

Carolina, that was a great trick!
I can't wait to see your next trick, Carolina.

Thank you, everyone. That was a great magic show!

 2，建立數字列表

　一，列表很是適合用於存儲數字集合，函數range（）可以輕鬆生成一系列的數字。　　

for value in range(1,5):
    print(value)

運行結果
1
2
3
4

　　二，使用range（）建立數字列表。可以使用函數list（）將range（）的結果直接轉換成列表。還可指定步長。

numbers = list(range(1,6))
print(numbers)

運行結果
[1, 2, 3, 4, 5]

 　　3、列表解析

　　列表解析將for循環和建立新元素的代碼合併成一行，並自動附加新元素。

　　語法：描述性的列表名 = 【表達式（用於存儲到列表中的值）  for循環】

squares = []
for value in range(1,11):
    squares.append(value**2)
print(squares)

View Code

[1, 4, 9, 16, 25, 36, 49, 64, 81, 100]

result

squares = [value**2 for value in range(1,11)]
print(squares)

View Code

[1, 4, 9, 16, 25, 36, 49, 64, 81, 100]

result

　　4、切片

　　1，處理列表的部分元素-稱之爲切片　

players = ['charles','martina','michael','florence','eli']
print(players[0:3])
print(players[1:4])
print(players[:4])
print(players[2:])
print(players[-3:])
print(players[:-3])

View Code

['charles', 'martina', 'michael']
['martina', 'michael', 'florence']
['charles', 'martina', 'michael', 'florence']
['michael', 'florence', 'eli']
['michael', 'florence', 'eli']
['charles', 'martina']

result

　　2，遍歷切片

players = ['charles','martina','michael','florence','eli']
print("\nHere are the first three players on my team:")
for player in players[:3]:
    print(player.title())

View Code

運行結果：
Here are the first three players on my team:
Charles
Martina
Michael

result

　　3，複製列表

3，元組

　　Python的元組與列表相似，不一樣之處在於元組的元素不能修改。

　　元組使用小括號，列表使用方括號。

　　元組建立很簡單，只須要在括號中添加元素，並使用逗號隔開便可。

　　以下實例：

　　

dimensions = (200,50)
#dimensions[0] = 250 修改無組值報錯
print(dimensions[0])
print(dimensions[1])

#遍歷元組中的全部值，for循環
for dimension in dimensions:
    print(dimension)
@修改元組變量
dimensions = (250,50)
print("\nModified dimensions:")
for dimension in dimensions:
    print(dimension)

View Code

運行結果：
200
50
200
50

Modified dimensions:
250
50

result