6. Python 运算符

Python操作符允许我们对变量进行公共处理。我们将通过示例和操作符优先级来研究不同类型的python操作符。

Python运算符

Python运算符是可以操作一个或多个操作数的值的特殊符号。

Python运算符类型

Python操作符可以分为几个类别。

• 算术运算符
• 逻辑运算符
• 比较运算符
• 位运算符
• 赋值运算符

Python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

输出：

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运算符优先级

python运算符的优先级表示运算符的优先级。当一个表达式中有多个运算符时，这一点就变得至关重要了。例如，考虑以下表达式：

>>> 2+3*4

现在，你认为这一系列的手术会是什么？我们可以加上2和3，然后把结果乘以4。另外，我们可以先把3和4相乘，然后再加上2。在这里我们可以看到运算符的优先级很重要。

下面是表示优先级的运算符列表。它是按降序排列的。这意味着上一组的优先级高于上一组。

1. 括号–；()
2. 指数化；**
3. 恭维，一元加减–；~, +, -
4. 乘、除、模和#8211；*, /, %
5. 加减法–；+, -
6. 左右移动–；>>, <<
7. 按位与–；&
8. 按位“或”与“异或”–；|, ^
9. 比较运算符–；==, !=, >, <, >=, <=
10. 赋值运算符-=

参考文献：Python官方文档