Python 学习笔记（十一）Python语句（一）

 1 >>> a = 2
 2 >>> b = 2
 3 >>> a == b  #判断a、b两个对象是否相等，返回结果为true,说明两个变量所引用的对象相等
 4 True
 5 >>> a is b
 6 True
 7 >>> id(a),id(b) #a 和ｂ　引用的同一个对象
 8 (54354784L, 54354784L)
 9 >>> da ={"lang":["python",c],"teacher":"cc"}
10 >>> import copy
11 >>> db =copy.deepcopy(da) #深拷贝
12 >>> db
13 {'lang': ['python', set([0, 1, 3, 5, 6])], 'teacher': 'cc'}
14 >>> id(da),id(db) #是不同的两个对象
15 (54489976L, 64755912L)
16 >>> da is db #判断是否为同一个对象
17 False
18 >>> da ==db #两个对象相等
19 True
20 >>> da !=db #两个对象不相等
21 False
22 >>> a,b =2,3
23 >>> a!=b 
24 True
25 >>> a<>b
26 True
27 >>> 321>1234
28 False
29 >>> "321">"1234"
30 True
31 >>>

 1 >>> a ="python"
 2 >>> b =[]
 3 >>> bool(a)
 4 True
 5 >>> bool(b)
 6 False
 7 >>> bool(0)
 8 False
 9 >>> bool(1)
10 True
11 >>> 4>3 and 4<9
12 True
13 >>> 4<3 and 4>9
14 False
15 >>> 4>3 or 4>9
16 True
17 >>> 4<3 or 4<9
18 True
19 >>> not(4>3)
20 False
21 >>> 4>3 and 4>9 or 4<5  #先执行4>3 为true,接着执行and的右边, or 4>9为false,则执行4<5为true,and的右边即为true, 所以此处返回true
22 True
23 >>>

1 >>> print "hello world"  #print语句
2 hello world3 >>> import math  #import语句
4 >>> a = 2 #赋值语句

 1 import random  #引入随机数模块
 2 a =random.randint(0,100)  #随机0到100的整数
 3 if a >50:
 4     print a  #注意：print前有四个空格
 5     print "a is bigger than 50"
 6 elif a==50:
 7     print a
 8     print "a is 50"
 9 else:
10     print a
11     print "a is smaller than 50"

>>> x = 2
>>> y = 8
>>> a ="python" if x>y else "web" 如果x>y 将python赋值给A,否则将web赋值给a.
>>> a
'web'
>>>