assume that variable a is 10 and variable b is 21:
Operator Description Example
+ Add - Add two objects a + b Output result 31
- Subtract - Get a negative number or subtract one number from another a - b output result - 11
* multiplication - multiply two numbers or return a string repeated several times a * b output result 210
/ divide - x divided by y b / a output result 2.1
% modulo - return the result of the division The remainder b % a outputs the result 1
** power - returns x to the y power a**b is 10 to the 21st power
// Round division - returns the integer part of the quotient 9//2 outputs the result 4 , 9.0//2.0 outputs the result 4.0
Python comparison operators
The following assumes that variable a is 10 and variable b is 20:
operator description instance
== equals - compares objects for equality (a == b) returns False.
!= not equal - Compares whether two objects are not equal (a != b) returns True.
> greater than - Returns whether x is greater than y (a > b) returns False.
< Less than - Returns whether x is less than y. All comparison operators return 1 for true and 0 for false. This is equivalent to the special variables True and False, respectively. Note the capitalization of these variable names. (a < b) returns True.
>= greater than or equal to - Returns whether x is greater than or equal to y. (a >= b) returns False.
<= less than or equal to - Returns whether x is less than or equal to y. (a <= b) returns True.
Python assignment operator
The following assumes that variable a is 10 and variable b is 20:
Operator Description Example
= Simple assignment operator c = a + b Assigns the result 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 The 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
//= rounding division assignment operator c //= a is equivalent to c = c // a
Python logical operators
The Python language supports logical operators, the following assumes that the variables a is 10 and b is 20:
operator logical expression description instance
and x and y Boolean "and" - if x is False, x and y return False, otherwise It returns the computed value of y. (a and b) returns 20.
or x or y boolean "or" - if x is True, it returns the value of x, otherwise it returns the computed value of y. (a or b) returns 10.
not not x boolean "not" - Returns False if x is True. It returns True if x is False. not(a and b) returns False
Python member operators
In addition to some of the above operators, Python also supports member operators, and the test instance contains a series of members, including strings, lists or tuples.
The operator description instance
in returns True if a value is found in the specified sequence, and False otherwise. x is in the y sequence, returns True if x is in the y sequence.
not in Returns True if no value is found in the specified sequence, False otherwise. x is not in the y sequence, returns True if x is not in the y sequence.
Python identity operator
The identity operator is used to compare the storage unit of two objects
| operator | describe | example |
|---|---|---|
| is | is is to determine whether two identifiers refer to an object | x is y , similar to id(x) == id(y) , returns True if it refers to the same object, otherwise returns False |
| is not | is not is to determine whether two identifiers refer to different objects | x is not y , like id(a) != id(b) . Returns True if the reference is not the same object, False otherwise. |