1. Operators
(1) Arithmetic operators:
(2) Relational operators:
(3) Assignment operator:
(4) Logical operators:
Priority: () > Not > and > or
2. Data type:
Raw_input (): Receive String type
Input (): Receive number Type
Integral type:
A =-100
ABS (a) to find the absolute value of a
A.__abs__ () to find the absolute value of a
Fu Type:
The round () method retains 1 decimal places by default, is calculated using the rounding method, and the last one is an even number.
A = 3.0 round (a) round (2)
Rounding is performed first, if the last digit of the decimal precision is even if the last digit of the decimal precision is rounded and then is odd, then all digits after the fiction point precision are discarded to guarantee the decimal precision, and the last one is even.
c = 2.555 D = 1.545 print (round (c,2)) print (round (d,2)) 2.56 1.54
Boolean type:
True False
3. String
dir () see what built-in methods
Type () to see what kind of
str1 = ' Aaaaabasdfxqs353235asdf ' print ( Str1.find (' fxq ')) 9 str1 = ' Aaaaabasdfxqs353235asdf ' print (str1.replace (' fxq ', ' fengxiaoqing ') aaaaabasdFengxiaoqings353235asdf str1 = ' Aaaaabasdfxqs353235asdf ' print (str1.split (' s ')) [' Aaaaaba ' , ' dfxq ', ' 353235a ', ' df '] str1 = ' Aaaaabasdfxqs353235asdf ' print (' SSS '. Join (Str1.split (' s ')) aaaaabaSSSdfxqSSS353235aSSSdf a = ' aaaaaba sdfx qs353 235asdf ' print (A.strip ()) print (a)  &Nbsp; print (A.lstrip ()) #去掉左边空格 print (A.rstrip ()) #去掉右边空格         AAAAABA  SDFX QS353 235ASDF aaaaaba sdfx qs353 235asdf Aaaaaba sdfx qs353 235asdf aaaaaba sdfx qs353 235asdf format () method: name = ' fengxiaoqing ' age = 30 home = ' Chengde ' print (' Hello ' +name) print (' hello {0} '). Format (name) print (' hello %s ') % name print (' hello %d ') % age print (' My age is:{0} my home: {1} '). Format (age,home) print (' {name}:{age} '. Format (name= ' Fxq ', age=20)) hellofengxiaoqing hello fengxiaoqing hello fengxiaoqing hello 30 my age is:30 my home: chengde fxq:20
4.list operation
' Append ', ' count ', ' extend ', ' index ', ' Insert ', ' Pop ', ' remove ', ' reverse ', ' sort ' str1 = ' 12poqiwrtgopwert ' str2 = list (STR1) print (Type (str1)) Print (Type (STR2)) print (list (str1)) print (dir (str2)) print (' # # # ' *20) a = [123, ' BBB ', ' Ace ') print (A[1]) print (A.index (' BBB ')) a.insert (1, ' AAA ') print (a) a.sort () print (a) a.reverse () print (a) a.append (' ooo ') print (a) a.pop () print (a) a.remove (123) print (a) a.pop (1) print (a) <type ' str ' > <type ' list ' > [' 1 ', ' 2 ', ' P ', ' o ', ' q ', ' i ', ' W ', ' r ', ' t ', ' G ', ' o ', ' P ', ' W ', ' E ', ' r ', ' t '] [' __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 '] ################################################ ################################ bbb 1 [ 123, ' aaa ', ' BBB ', ' Ace '] [123, ' aaa ', ' Ace ', ' BBB '] [' BBB ', ' Ace ', ' aaa ', 123] [123, ' AAA ', ' Ace ', ' bbb ', ' ooo '] [123, ' aaa ', ' Ace ', ' BBB '] [' aaa ', ' Ace ', ' BBB '] [' aaa ', ' BBB ']
List slices:
A = [one, ' 222 ', ' $ ', 444,555,666] print (a[3:]) print (A[1:5]) print (A[1:6:2]) print (A[:4]) print (a[-1]) pri NT (a[-2:]) print (a[-4:-2]) [444, 555, 666] [' 222 ', ' 33 ', 444, 555] [' 222 ', 444, 666] [11, ' 222 ', ' 33 ', 444] 666 [555, 666] [' 33 ', 444]
Examples of operators, data types, strings, and list operations in Python