Pythonic Programming example and brief analysis

1. List

list[start: End: Increment]

Value passing and address passing

A = [2,1= a      # address delivery  B = a[:] Value passed a.sort ()print a    # [up] print b    #[+]

2. Sorting sort ()

 d = {1: " s   ", 2:"  a   "    sorted (D.items (), key = lambda  x:x[1] ) /* Sort by the 2nd element of the list element */

# Sorted (iterable, cmp=none/* function */, key=none/* function */, Reverse=false)  = ['aaa','a','aa'  = len)#The key value is the total function to be called print ll

Print sorted ("Sorting1234", Key=lambda x: (X.isdigit (), X.isdigit () and int (x)% 2 = = 0, X.isupper (), X.islower (), x)) #[' G ', ' i ', ' n ', ' O ', ' r ', ' t ', ' S ', ' 1 ', ' 3 ', ' 2 ', ' 4 ']

3. anonymous function lambda

# Lambda parameter: return value Lambda x:x+1

4....for. ... in ... if ...

A = [All-in-a-z]printforif i>0]

5.filter map Reduce

Filter (function, sequence): Executes function (item) on item in sequence, and the item that executes the result of true is composed of a list/string/ Tuple (depending on the type of sequence) returned

Print Lambda x:x!='a'abcd ')   #' BCD ' 

Map (function, sequence): Executes function (item) on item in sequence, and the result of execution consists of a list return:

Print Lambda x:x+1, Range (3))  #[+]

Reduce (function, sequence, starting_value): Calls the function in the order of the item in the sequence, and if there is a starting_value, it can also be called as an initial value. For example, you can use the list to sum

Print Lambda x,y:x+y, Range (3), ten)  #

6. Generator Generator

 for  in range (3)) for in a:print I

7. Range(start , end , increment )

Print  Range (1,9,2)  #[1, 3, 5, 7]

8...? ...:...

if else b    # fully equivalent andor  [c]) [0] (andor C    # not exactly equivalent, B cannot be false

F

Pythonic Programming example and brief analysis