python.day.01--operator Classification

Operator Classifications:

Arithmetic operators, assignment operators, comparison operators, logical operators, member operators

One, arithmetic operators

Operator	Describe	Example (a=3,b=2)
+	Add operation: Two number added	A + b = 5
-	Minus operation: two number subtraction	A-B = 1
*	Multiplication: Multiply by two numbers	A * b = 6
/	Divide operation: Two number division (note and c,c++ "/" difference)	A/b =1.5
%	Take-rest operation: Two-digit division-taking surplus	A% B = 1
**	Power operation: Returns the power of B of a	A * * b = 9
//	Rounding operation: Returns the integer part of the quotient	A//b = 1

Note:%, to output the percent sign "%" must be print ("percent")

Second, assignment operation

operator	Description	Example
=	Simple assignment operator	c = A + B assigns the result of the operation of A + B to c
+=	Addition assignment operator	c + = A is equivalent to C = C + A
-=	Subtraction assignment operator	C-= A is equivalent to C = c-a
*=	Multiplication assignment operator	C *= A is equivalent to C = c * A
/=	Division assignment operator	C/= A is equivalent to C = c/a
%=	Modulo assignment operator	C%= A is equivalent to C = c% A
**=	Power assignment operator	C **= A is equivalent to C = c * * A
//=	Take the divisible assignment operator	C//= A is equivalent to C = c//A

Third, comparative operations

1.==, >, >=, <=,! =2. Return Result: Boolean true, Faluse (all comparison operators return 1 for true, return 0 for false) 3. Application scenario: A common set of comparison values, which we call conditional expressions

operator	Description	Example
==	Equals-compares objects for equality	(A = = B) returns FALSE.
!=	Not equal-compares two objects for unequal	(A! = B) returns TRUE.
>	Greater than-returns whether x is greater than Y	(A > B) returns FALSE.
<	Less-Returns whether x is less than Y. All comparison operators return 1 for true, and return 0 for false. This distinction is equivalent to the special variable true and false. Note that these variable names are capitalized.	(A < B) returns TRUE.
>=	Greater than or equal-returns whether X is greater than or equal to Y.	(a >= B) returns FALSE.
<=	Less than or equal-returns whether X is less than or equal to Y.	(a <= B) returns True.

Four, logical operators

1. And, Or2, and generally are often used by us as conditional expressions: If, while3, Result: and: True True or false false

operator	Logical Expressions	Description	Example
and	X and Y	Boolean "and"-if x is False,x and y returns FALSE, otherwise it returns the computed value of Y.	(A and B) returns 20.
Or	X or Y	Boolean "or"-if X is non-0, it returns the value of x, otherwise it returns the computed value of Y.	(A or B) returns 10.
Not	Not X	Boolean "Non"-returns False if X is True. If X is False, it returns TRUE.	Not (A and B) returns False

Five, member operators

1.in, not in2. Result: Boolean value True, Faluse

operator	Description	Example
Inch	Returns False if the value found in the specified sequence returns True.	x in the y sequence, if X returns True in the y sequence.
Not in	Returns True if no value is found in the specified sequence, otherwise False.	X is not in the Y sequence if x does not return True in the y sequence.

Six, identity operators

operator	Description	Example
Is	is to determine whether two identifiers are referenced from an object	X is Y, similar to ID (x) = = ID (y), returns True if the same object is referenced, otherwise False
is not	Is does not determine whether two identifiers are referenced from different objects	X is not y, similar to ID (a)! = ID (b). If the reference is not the same object, the result returns True, Otherwise, False is returned.

Usage examples:

#python identity operatorA = 20b= 20#is to determine whether two identifiers refer to the same objectif(A isb):Print('A and B have the same identity')Else:    Print('A and B do not have the same identity') #is does not determine whether two identifiers are referenced from different objectsif(A is  notb):Print('A and B do not have the same identity')Else:    Print('A and B have the same identity') #Modify the value of variable Bb = 30if(A isb):Print('A and B have the same identity')Else:    Print('A and B do not have the same identity') if(A is  notb):Print('A and B do not have the same identity')Else:    Print('A and B have the same identity')
Result of instance output: A and B have the same identity A and B have the same identity A and b do not have the same identity A and b do not have the same identity

Seven, Python operator precedence

The following table lists the precedence of operators: High---> Low

operator	Description
**	Index (highest priority)
~ + -	Bitwise flip, unary Plus and minus (the last two methods are called [email protected] and [email protected])
* / % //	Multiply, divide, modulo, and divide
+ -	Addition subtraction
>> <<	Shift right, left shift operator
&	Bit ' and '
^ |	Bitwise operators
<= < > >=	Comparison operators
<> = = =	equals operator
= %= /= //= -= += *= **=	Assignment operators
Is isn't	Identity operator
In No in	Member operators
Not OR and	logical operators

python.day.01--operator Classification