string='''hahaha
wo
ni
haha
'''
print(string)#三引号有多行功能
hahaha
wo
ni
haha
In [7]:
print('a\nb')#换行
a
b
In [8]:
a=1
print(a)
1
In [9]:
del a#删除变量
print(a)
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
<ipython-input-9-29a34d62998c> in <module>()
1 del a
----> 2 print(a)
NameError: name 'a' is not defined
In [10]:
b=2E3#exp指数
c=2e3
In [11]:
print(b,c)
2000.0 2000.0
In [15]:
c='llovepython'#切片，注意范围
print(c[1:4])
print(c[1:-1])
lov
lovepytho
In [9]:
sum = lambda (a,b):a+b
sum(1,3)
File "<ipython-input-9-f273882c85a6>", line 1
sum = lambda (a,b):a+b
^
SyntaxError: invalid syntax
In [3]:
sum = lambda a,b:a+b#匿名函数,不占内存存取参数
sum(1,3)
Out[3]:
4
In [8]:
def member(name,*duobianliang):#变长参数
print(name)
print(duobianliang)
return
member('lili',1,'15years old')
lili
(1, '15years old')
In [10]:
def py(name,age=17):#默认参数
print(name)
print(age)
py('xiaohua')
py('xiaoli',18)
xiaohua
17
xiaoli
18
In [15]:
def difference(a,b):#全局变量，局部变量
sum=a+b
return sum
sum=10
print('局部变量值:',difference(1,3))
print('全局变量值:',sum)
局部变量值: 4
全局变量值: 10
In [16]:
[x**2 for x in range(1,10,2)]#list快速生成
Out[16]:
[1, 9, 25, 49, 81]
