码迷,mamicode.com
首页 > 编程语言 > 详细

向python3进发

时间:2017-01-15 19:28:47      阅读:250      评论:0      收藏:0      [点我收藏+]

标签:ict   返回   final   python3.x   exp   效果   lock   python3   sed   

在Python2.x中,交互输入有input和raw_input两种方法

  1. input-----------tmd是个坑,就别用
  2. raw_input------把输入无论是Int或str都当做是str处理,加入要取到数字,需要强制类型转化

在Python3.x中,只有input方法,但是效果跟Python2.x的raw_input一样一样的.

 1 #python2.x
 2 >>> s = int(raw_input(input:))
 3 input:a
 4 >>> type(s)
 5 <type str>
 6 
 7 >>> s = raw_input(input:)
 8 input:99
 9 >>> type(s)
10 <type str>
12 >>> score = int(raw_input(input:))
13 input:99
14 >>> type(score)
15 <type int>
16 
17 #python3.x (python 3.x 一切皆类型....看type输出.....)
18 >>> s = int(input(input:))
19 input:a
20 >>> type(s)
21 <class str>
22 
23 >>> s = input(input:)
24 input:99
25 >>> type(s)
26 <class str>
27 
28 >>> score = int(input(input:))
29 input:99
30 >>> type(score)
31 <class int>

 一种不常见的格式化输出:

技术分享
 1 >>> info=‘‘‘
 2 ... ---------info---------
 3 ... name:{_name}
 4 ... age:{_age}
 5 ... ‘‘‘.format(_name=zwj,_age=26)
 6 >>> print (info)
 7 
 8 ---------info---------
 9 name:zwj
10 age:26
View Code

 

>>> print (name:{name},age:{age}.format(name=zwj,age=11))
name:zwj,age:11

 

 一个可以密文输入的模块getpass

>>> import getpass
>>> username = input(username:)
username:zwj
>>> password = getpass.getpass(password:)
password:
>>> print (user:%s,pwd:%s%(username,password))
user:zwj,pwd:mima
>>> 

 Python3的keys(), values(), items()返回的都是迭代器,如果需要像Python2一样返回列表,只要传给list就行了(Python2中iteritems()方法同样返回迭代器,Python3中已经移除)

技术分享
>>> import sys
>>> sys.version
3.5.2 (v3.5.2:4def2a2901a5, Jun 26 2016, 10:47:25) \n[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)]
>>> d={k1:v1,k2:v2}
>>> print (d.keys(),d.values(),d.items())
dict_keys([k1, k2]) dict_values([v1, v2]) dict_items([(k1, v1), (k2, v2)])
>>> print (list(d.keys()),list(d.values()),list(d.items()))
[k1, k2] [v1, v2] [(k1, v1), (k2, v2)]
>>> 
View Code

除法运算

技术分享
>>> a=3
>>> b=2
>>> a/b  #默认浮点
1.5
>>> a//b #取整
1
>>> a%b
1
>>> b%a
2
>>> b/a
0.6666666666666666
>>> c=5
>>> d=7
>>> c//7
0
View Code

 一个可以密文输入的模块getpass

>>> import getpass
>>> username = input(username:)
username:zwj
>>> password = getpass.getpass(password:)
password:
>>> print (user:%s,pwd:%s%(username,password))
user:zwj,pwd:mima
>>> 

 Python3的keys(), values(), items()返回的都是迭代器,如果需要像Python2一样返回列表,只要传给list就行了

技术分享
>>> import sys
>>> sys.version
3.5.2 (v3.5.2:4def2a2901a5, Jun 26 2016, 10:47:25) \n[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)]
>>> d={k1:v1,k2:v2}
>>> print (d.keys(),d.values(),d.items())
dict_keys([k1, k2]) dict_values([v1, v2]) dict_items([(k1, v1), (k2, v2)])
>>> print (list(d.keys()),list(d.values()),list(d.items()))
[k1, k2] [v1, v2] [(k1, v1), (k2, v2)]
>>> 
View Code

除法运算

技术分享
>>> a=3
>>> b=2
>>> a/b  #默认浮点
1.5
>>> a//b #取整
1
>>> a%b
1
>>> b%a
2
>>> b/a
0.6666666666666666
>>> c=5
>>> d=7
>>> c//7
0
View Code

位运算

技术分享
>>> a=60    #60 = 0011 1100 
>>> b=13    #13 = 0000 1101 
>>> a&b      #12 = 0000 1100  
12
>>> a|b        #61 = 0011 1101 
61
>>> a^b        #49 = 00110001
49
>>> ~a        #-61 = 1100 0011
-61
>>> a<<2    #240 = 1111 0000
240
>>> a>>2    #15 = 0000 1111
15
>>> 
View Code

try/except/else/finaly

技术分享
>>> print (1)
1
>>> try:
    print (1)
except:
    print (2)
else:
    print (3)
finally:
    print (4)

    
1
3
4

----------------
>>> try:
    print (x)
except:
    print (2)
else:
    print (3)
finally:
    print (4)

    
2
4
View Code

 给字典排序

from heapq import nsmallest,nlargest

l = [
    {
        name:good4,
        increase: 69,
        price: 20,
    },
    {
        name:good1,
        increase: 45,
        price: 20,
    },
    {
        name:good2,
        increase: 59,
        price: 24,
    },
    {
        name:good3,
        increase: 18,
        price: 10,
    },
]

r = nsmallest(3,l,key=lambda s:(s[price],s[increase]))
print(r)
print(r[0])

r = nlargest(3,l,key=lambda s:(s[price],s[increase]))
print(r)
print(r[0])


out:
[{price: 10, name: good3, increase: 18}, {price: 20, name: good1, increase: 45}, {price: 20, name: good4, increase: 69}]
{price: 10, name: good3, increase: 18}
[{price: 24, name: good2, increase: 59}, {price: 20, name: good4, increase: 69}, {price: 20, name: good1, increase: 45}]
{price: 24, name: good2, increase: 59}

 

向python3进发

标签:ict   返回   final   python3.x   exp   效果   lock   python3   sed   

原文地址:http://www.cnblogs.com/diaosir/p/6224461.html

(0)
(0)
   
举报
评论 一句话评论(0
登录后才能评论!
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码!