Detailed explanation of Python operator precedence order and common mistakes to avoid

In-depth analysis of Python operator priority order to avoid common mistakes

Operator priority in the Python language is the rule that controls the execution order of each operator in an expression . When writing code, it is very important to correctly understand and use operator precedence, otherwise unpredictable errors will occur.

In Python, operators are executed in order from high to low priority, and operators with the same priority are executed in order from left to right.

Below we will introduce the common operators in Python one by one and give specific code examples. Let’s take a closer look.

1. Bracket operator ()
   The bracket operator has the highest priority and can be used to change the priority order of ordinary operators and can also be used to improve the readability of the code.

Sample code:

result = (1 + 2) * 3
print(result)  # 输出结果为 9

2. Power operator **
   The power operator has the second highest priority and is used to calculate the power of a number.

Sample code:

result = 2 ** 3
print(result)  # 输出结果为 8

3. Sign operator -
   The sign operator is used to switch the sign of a number.

Sample code:

result1 = +5
result2 = -5
print(result1)  # 输出结果为 5
print(result2)  # 输出结果为 -5

4. Multiplication and division remainder operators * / %
   Multiplication and division remainder operators are executed in order from left to right.

Sample code:

result1 = 10 / 3
result2 = 10 % 3
print(result1)  # 输出结果为 3.3333333333333335
print(result2)  # 输出结果为 1

5. Addition and subtraction operators -
   Addition and subtraction operators are also executed from left to right.

Sample code:

result1 = 10 + 5
result2 = 10 - 5
print(result1)  # 输出结果为 15
print(result2)  # 输出结果为 5

6. Left shift right shift operator<< >>
   Left shift right shift operator is used for binary numbers Perform displacement operations.

Sample code:

result1 = 16 << 2
result2 = 16 >> 2
print(result1)  # 输出结果为 64
print(result2)  # 输出结果为 4

7. Bit operator & | ^
   The bit operator is used to perform AND, OR, and XOR operations on binary numbers.

Sample code:

result1 = 5 & 3
result2 = 5 | 3
result3 = 5 ^ 3
print(result1)  # 输出结果为 1
print(result2)  # 输出结果为 7
print(result3)  # 输出结果为 6

8. Comparison operator== != > < >= <=
   Comparison operator is used to compare two Value relationship, returns a Boolean value.

Sample code:

result1 = 5 == 3
result2 = 5 != 3
result3 = 5 > 3
result4 = 5 < 3
print(result1)  # 输出结果为 False
print(result2)  # 输出结果为 True
print(result3)  # 输出结果为 True
print(result4)  # 输出结果为 False

9. Boolean operators and or not
   Boolean operators are used to perform logical operations on Boolean values.

Sample code:

result1 = True and False
result2 = True or False
result3 = not True
print(result1)  # 输出结果为 False
print(result2)  # 输出结果为 True
print(result3)  # 输出结果为 False

10. Assignment operator = = -= *= /=
    The assignment operator is used to assign a value to a variable.

Sample code:

result1 = 10
result1 += 5  # 等同于 result1 = result1 + 5
print(result1)  # 输出结果为 15

result2 = 10
result2 *= 2  # 等同于 result2 = result2 * 2
print(result2)  # 输出结果为 20

By deeply understanding the order of operator precedence in Python, and using operators correctly, we can avoid common mistakes, improve the accuracy of our code, and readability.

Hope the above content can help readers who have questions about the precedence order of Python operators. Thanks for reading!

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