Python操作符-快速查询

Python的运算符允许我们对变量进行常见的处理。我们将通过示例讨论不同类型的运算符以及运算符的优先级。它们是可以操纵一个或多个操作数值的特殊符号。

Python操作符列表

Python的操作符可以分为几个类别。

• Assignment Operators
• Arithmetic Operators
• Logical Operators
• Comparison Operators
• Bitwise Operators

Python赋值运算符

赋值运算符包括基本的等号（=）赋值运算符。

然而为了简化代码并减少冗余，Python还包含了算术赋值运算符。

这包括了Python中用于加法赋值的+=操作符，地板除法的赋值运算符//=，以及其他操作符。

以下是Python中所有算术赋值运算符的列表。

使用赋值运算符

# take two variable, assign values with assignment operators
a=3
b=4

print("a: "+str(a))
print("b: "+str(b))

# it is equivalent to a=a+b
a+=b

print("a: "+str(a))
print("b: "+str(b))

# it is equivalent to a=a*b
a*=b
print("a: "+str(a))
print("b: "+str(b))

# it is equivalent to a=a/b
a/=b
print("a: "+str(a))
print("b: "+str(b))

# it is equivalent to a=a%b
a%=b
print("a: "+str(a))
print("b: "+str(b))

# it is equivalent to a=a**b ( exponent operator)
a**=b
print("a: "+str(a))
print("b: "+str(b))

# it is equivalent to a=a//b ( floor division)
a//=b
print("a: "+str(a))
print("b: "+str(b))

Python的算术运算符

#create two variables
a=100
b=200

# addition (+) operator
print(a+b) 

# subtraction (-) operator
print(a-b) 

# multiplication (*) operator
print(a*b)

# division (/) operator
print(b/a)

# modulus (%) operator
print(a%b) # prints the remainder of a/b

# exponent (**) operator
print(a**b) #prints a^b

Python比较运算符

# create two variables
a=100
b=200

# (==) operator, checks if two operands are equal or not
print(a==b)

# (!=) operator, checks if two operands are not equal
print(a!=b)

# (>) operator, checks left operand is greater than right operand or not
print(a>b)

# (<) operator, checks left operand is less than right operand or not
print(a<b)
#(>=) operator, checks left operand is greater than or equal to right operand or not
print(a>=b)

# (<=) operator, checks left operand is less than or equal to right operand or not
print(a<=b)

Python的位运算符

#create two variables
a=10 # binary 1010
b=7  # binary 0111

# Binary AND (&) operator, done binary AND operation
print(a&b)

# Binary OR (|) operator, done binary OR operation
print(a|b)

# Binary XOR (^) operator, done binary XOR operation
print(a^b)

# Binary ONEs Compliment (~) operator, done binary One's Compliment operation
print(~a)

# Binary Left Shift (<<) operator, done binary Left Shift operation
print(a<<1) 
# Binary Right Shift (>>) operator, done binary Right Shift operation
print(a>>1)

Python 逻辑运算符

#take user input as int
a=int(input())

# logical AND operation

if a%4==0 and a%3==0:
    print("divided by both 4 and 3")

# logical OR operation
if a%4==0 or a%3==0:
    print("either divided by 4 or 3")

# logical NOT operation
if not(a%4==0 or a%3==0):
    print("neither divided by 4 nor 3")

Python运算符优先级

这些运算符的优先级指的是运算符的优先级水平。当一个表达式中包含多个运算符时，这就变得至关重要。例如，考虑下面的表达式：

>>> 2+3*4

现在，你认为操作序列应该是什么？我们可以先加2和3，然后将结果乘以4。另外，我们也可以先将3和4相乘，然后再与2相加。从这里我们可以看出操作符的优先级是很重要的。

以下是一份运算符优先级的列表，按降序排列。这意味着上层组具有比下层组更高的优先级。

1. 括号 – （）

1. 指数运算 – **

1. 补数、一元正负 – ~、+、-

1. 乘法、除法、取模 – *、/、%

1. 加法和减法 – +、-

1. 右移和左移 – >>、<< 位与运算 – & 位或和异或运算 – |、^ 比较运算符 – ==、!=、>、<、>=、<=

赋值运算符 – =