Python Learning Note Day4

1. Set Set

Set set is an unordered and non-repeating collection

Add Features:

S1 = set ()
S1.add ("Wang")
Print (S1)

Difference function (find different elements from the current collection and generate a new collection):

S1 = set (["Wang", "Pan", "Lai"])
S2 = s1.difference (["Wang", "Pan"])
Print (s2)

Result: {' Lai '}

Difference_update (removes duplicate elements from the current collection, does not generate a new collection):

S1 = set (["Wang", "Pan", "Lai"])
S1.difference_update (["Pan", "Lai"])
Print (S1)

Result: {' Wang '}

1. Queue
Single queue: FIFO
Bidirectional queue (Collections): Both sides can be entered and taken

2. Dictionary {}, tuple (), list []

3. Deep Copy (Copy.deepcopy ()) and shallow copy (Copy.copy ())
  For both numbers and strings, the result memory address is the same

4. Functions


The try statement in the function:

#-*-Coding:utf-8-*-
# Author:cslzy
# email: [Email protected]
# description:send something to someone.
# date:20151104 18:33:08
Import Smtplib
From Email.mime.text import Mimetext as MT

def Mail (user):
    ret = ' ture '
    Try
        msg = Mimetext (' Hello! ', ' Plaon ', ' utf-8 ')
        msg[' from ' = formataddr ([' Wang Hope ', ' [email protected] ')
        msg[' to ' = formataddr ([' Wang Hope ', ' [email protected] ')
        msg[' Subject ' = ' theme '

        Server = Smtplib. SMTP (' smtp.126.com ', 25)
        Server.login (' [email protected] ', ' password ')
        Server.sendmail (' [email protected] ', [User,],msg.as_string ())
        Server.quit ()
    Except Exception:
        ret = ' false '
    return ret
ret = mail (' [email protected] ')
Print (ret)

The default parameter must be written back.

Dynamic Parameters (*: tuple, * * dictionary):

Def han (*arg,**karg):
    Print (Arg,type (ARG))
    Print (Karg,type (Karg))

Han (7,89,3,62,n1=78,n2=88)

Def han (*arg,**karg):
    Print (Arg,type (ARG))
    Print (Karg,type (Karg))

L1 = [7,89,3,62]
L2 = {' N1 ': +, ' N2 ': 88}
Han (*l1,**l2)

#l1 = ' {0} is {1} '
L1 = ' {name} ' is {role} '
N1 = {' name ': ' Ren ', ' role ': ' Dashen '}
#l2 = L1.format (' ren ', ' dashen ')
#l2 = L1.format (name= ' ren ', role= ' Dashen ')
L2 = L1.format (**n1)
Print (L2)

Simple function lambda expression:

code comment for python #-*-Coding:utf-8-*-

If you want to write Chinese in the Python2 py file, you must add a line to declare the file encoded comments, otherwise python2 will use ASCII encoding by default.

Reference: http://blog.csdn.net/arbel/article/details/7957782

Python built-in functions:
Http://www.runoob.com/python/python-built-in-functions.html

Python Learning Note Day4