python核心编程（第二版）第二章学习笔记

1.版本3.40的print string是不行的，需要在输出的字符串上加括号

mystring='my name is '
print(mystring)

2.print和字符串格式操作符（%）合作

1 print("%s is  %d word "%("test",1))
2 #%s=string %d=整形
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3.raw_input()和input()------------用的python3.4,所以用raw_input（)出错，查资料才知道，3.4中没有了raw_input()函数

1 >>>name=input('enter your name')
2 enter your name 34
3 >>>type(name)
4 <class 'str'>
5 >>>age=int(input('enter your age'))
6 enter your age 34
7 >>>type(age)
8 <class 'int'>
9 ///raw_input()是自动区别str和int的，而input都是“str"
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 4.列表（[]）和元组(())元组的单个元素不可以改变

 1 >>> alist=[1,2,4,6]
 2 >>> alist
 3 [1, 2, 4, 6]
 4 >>> type(alist)
 5 <class 'list'>
 6 >>> alist[3]
 7 6
 8 >>> alist[3]=67
 9 >>> alist[3]
10 67
11 >>> atuple=('test1','test2','test4','test7')
12 >>> atuple
13 ('test1', 'test2', 'test4', 'test7')
14 >>> type(atuple)
15 <class 'tuple'>
16 >>> atuple[2]
17 'test4'
18 >>> atuple[2]='gs'
19 Traceback (most recent call last):
20   File "<pyshell#59>", line 1, in <module>
21     atuple[2]='gs'
22 TypeError: 'tuple' object does not support item assignment
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posted @ 2014-04-27 21:46  Jianwen_Zheng  阅读(206)  评论(0)    收藏  举报