My way to Python - Day03

 1 Python 2.7.6 (default, Mar 22 2014, 22:59:56) 
 2 [GCC 4.8.2] on linux2
 3 Type "help", "copyright", "credits" or "license" for more information.
 4 >>> import collections
 5 >>> c1 = collections.Counter()
 6 >>> str1 = ‘fujafksabfaskfjaslfl jshjfkk fhsfj hfajsjfsk fj‘
 7 >>> c1 = collections.Counter(str1)
 8 >>> c1  # 对于字符串操作的结果是：为每个出现的字符计数
 9 Counter({‘f‘: 11, ‘j‘: 8, ‘s‘: 7, ‘a‘: 5, ‘k‘: 5, ‘ ‘: 4, ‘h‘: 3, ‘l‘: 2, ‘b‘: 1, ‘u‘: 1})
10 >>> list1 = [11,22,22,33,33,33,44,44,44,44]
11 >>> c1 = collections.Counter(list1)
12 >>> c1  # 对于列表操作的结果是：为每个出现的元素计数
13 Counter({44: 4, 33: 3, 22: 2, 11: 1})
14 >>> 

1 dic ={}
2 dic = {‘k1‘:[]}      # → 这两行等同于下例中的一行(#←)
3 dic[‘k1‘].append(1)  # → 这两行等同于下例中的一行(#←)

1 from collections import defaultdict
2 dic = collections.defaultdict(list)   # ←
3 dic[‘k1‘].append(1)

 1 >>> from collections import defaultdict  # 使用默认字典，需要先导入defaultdict
 2 >>> dic = {}
 3 >>> dic = collections.defaultdict(list)  # 创建一个默认字典对象，把字典的value的默认类型置为列表
 4 >>> dic[‘k1‘].append(1) # 向字典中添加一个key k1<list类型>，并向k1中append一个元素1
 5 >>> dic
 6 defaultdict(<type ‘list‘>, {‘k1‘: [1]})
 7 >>> 
 8 >>> dic1 = {‘k1‘:1}
 9 >>> dic1
10 {‘k1‘: 1}
11 >>> 
12 >>> dic1 = collections.defaultdict(list)
13 >>> dic1
14 defaultdict(<type ‘list‘>, {})
15 >>> 
16 >>> dic1.append(22)  # 直接对dict1做append操作会报错，因为字典不能通过append进行赋值
17 Traceback (most recent call last):
18   File "<stdin>", line 1, in <module>
19 AttributeError: ‘collections.defaultdict‘ object has no attribute ‘append‘
20 >>> dic1[‘k2‘].append(22)  # 可以对默认字典中的列表元素做append操作
21 >>> dic1
22 defaultdict(<type ‘list‘>, {‘k2‘: [22]})
23 >>> 

1 >>> Mytuple = collections.namedtuple(‘Mytuple‘,[‘x‘,‘y‘])
2 >>> 
3 >>> n = Mytuple(x=1,y=2)
4 >>> n.x
5 1
6 >>> n.y
7 2
8 >>>

 1 >>> import Queue
 2 >>>
 3 >>> q = Queue.Queue(10)
 4 >>>
 5 >>> q.put(1)
 6 >>> q.put(2)
 7 >>> q.put(3)
 8 >>> q
 9 <Queue.Queue instance at 0x7f3975f505a8>
10 # 此处返回的是这个对象实例的内存地址
11 # 之所以没有返回队列中所有的元素是因为
12 # 在Queue的类的定义中没有实现__str__的方法。
13 >>> q.get()
14 1
15 >>> q.get()
16 2
17 >>> q.get()
18 3
19 >>> q.get() # 此时队列里已经没有元素了，再get则会hang住。
20 
21 
22 
23 
24 ^C^C

 1 >>> dir(list)
 2 [‘__add__‘, ‘__class__‘, ‘__contains__‘, ‘__delattr__‘, ‘__delitem__‘, ‘__delslice__‘, ‘__doc__‘, ‘__eq__‘, ‘__format__‘, ‘__ge__‘, ‘__getattribute__‘, ‘__getitem__‘, ‘__getslice__‘, ‘__gt__‘, ‘__hash__‘, ‘__iadd__‘, ‘__imul__‘, ‘__init__‘, ‘__iter__‘, ‘__le__‘, ‘__len__‘, ‘__lt__‘, ‘__mul__‘, ‘__ne__‘, ‘__new__‘, ‘__reduce__‘, ‘__reduce_ex__‘, ‘__repr__‘, ‘__reversed__‘, ‘__rmul__‘, ‘__setattr__‘, ‘__setitem__‘, ‘__setslice__‘, ‘__sizeof__‘, ‘__str__‘, ‘__subclasshook__‘, ‘append‘, ‘count‘, ‘extend‘, ‘index‘, ‘insert‘, ‘pop‘, ‘remove‘, ‘reverse‘, ‘sort‘]
 3 >>> 
 4 >>> help(list.__iter__)
 5 
 6 
 7 Help on wrapper_descriptor:
 8 
 9 __iter__(...)
10     x.__iter__() <==> iter(x)
11 (END)

 1 # 方法1
 2 >>> li = [11,22,33,44,55,66]
 3 >>> for i in li:
 4 ...     print i
 5 ...
 6 11
 7 22
 8 33
 9 44
10 55
11 66
12 >>>
13 # 方法2
14 >>> li = [11,22,33,44,55,66]
15 >>> for i in range(len(li)):
16 ...     print li[i]
17 ...
18 11
19 22
20 33
21 44
22 55
23 66
24 >>>

1 >>> 
2 >>> range(10)
3 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
4 >>> 
5 >>> xrange(10)
6 xrange(10)
7 >>> 

 1 # 基于range的冒泡排序算法
 2 li = [13, 22, 6, 99, 11]
 3 
 4 for m in range(len(li)-1):
 5 
 6     for n in range(m+1, len(li)):
 7         if li[m]> li[n]:
 8             temp = li[n]
 9             li[n] = li[m]
10             li[m] = temp
11 
12 print li

 1 >>> li = [‘stephen‘,‘‘,25]
 2 >>> all(li)
 3 False
 4 >>> any(li)
 5 True
 6 >>> 
 7 >>> li = [‘stephen‘,‘password‘,25]
 8 >>> all(li)
 9 True
10 >>> any(li)
11 True
12 >>> 
13 >>> li = [‘‘]
14 >>> all(li)
15 False
16 >>> any(li)
17 False
18 >>> 
19 >>> 

 1 >>> li =  [11,22,33,44,55,66]
 2 >>> for k,v in enumerate(li):
 3 ...     print k,v
 4 ... 
 5 0 11
 6 1 22
 7 2 33
 8 3 44
 9 4 55
10 5 66
11 >>> 
12 >>> for k,v in enumerate(li,1):
13 ...     print k,v
14 ... 
15 1 11
16 2 22
17 3 33
18 4 44
19 5 55
20 6 66
21 >>> 
22 >>> 

 1 #!/usr/bin/env python
 2 # -*- coding:utf-8 -*-
 3 __author__ = ‘Stephen‘
 4 
 5 def email(arg):
 6 #print arg
 7 
 8 if __name__ == ‘__main__‘:
 9 cpu = 99
10 ram = 50
11 disk = 95
12 
13 for i in range(1):
14     if cpu > 90:
15         alert = ‘cpu is ERROR‘
16         email(alert)
17     if ram > 90:
18         alert = ‘memory is ERROR‘
19         email(alert)
20     if disk > 90:
21         alert = ‘disk is ERROR‘
22         email(alert)

C:\Python27\python.exe G:/python/day03/def_function.py
cpu is ERROR
disk is ERROR

Process finished with exit code 0

 1 #!/usr/bin/env python
 2 # -*- coding:utf-8 -*-
 3 __author__ = ‘Stephen‘
 4 
 5 import smtplib
 6 from email.mime.text import MIMEText
 7 from email.utils import formataddr
 8 
 9 def email(arg): # 此处的arg为形式参数，简称形参。不赋值的时候没有实际意义。
10     msg = MIMEText(‘邮件内容‘, ‘plain‘, ‘utf-8‘)
11     msg[‘From‘] = formataddr(["Stephen",‘xxx@126.com‘])
12     msg[‘To‘] = formataddr(["thatsit",‘xxx@qq.com‘])
13     msg[‘Subject‘] = "监控报警邮件"
14 
15     server = smtplib.SMTP("smtp.126.com", 25)
16     server.login("mail-address@126.com", "PASSWORD")
17     server.sendmail(‘xxx@126.com‘, [‘xxx@qq.com‘,], msg.as_string())
18     server.quit()
19 
20 
21 if __name__ == ‘__main__‘:
22     cpu = 99
23     ram = 50
24     disk = 95
25 
26     for i  in  range(10):
27         if cpu > 90:
28             alert = ‘cpu is ERROR 第%d次‘ %i
29             email(alert) # 此处的alert在赋值之后就是实际参数。
30         if ram > 90:
31             alert = ‘memory is ERROR 第%d次‘ %i
32             email(alert)
33         if disk > 90:
34             alert = ‘disk is ERROR 第%d次‘ %i
35             email(alert)

1 def func(**kwargs):
2      print kwargs
3 
4 func (k1=123,k2=‘sss‘)
5 
6 dic = {k1:123,k2:234}
7 func (**dic)

1 r,只读
2 w,清空原文件写
3 a,可读,可写,只能以追加的方式写
4 
5 r+,可读可写
6 w+ <==> w
7 a+ <==> a