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Python Operator Precedence



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In Python, Operator precedence determines the order of operation in an expression with multiple operands and operators. Operator precedence provides the priority of operators that are used in expression. That is, operator precedence determines which operation carried out first, then which operation carried out second, and so on.

That is, if there are multiple operands and operators in an expression, or if we need to create an expression with multiple operands and operators, then we need operator precedence table to understand about the precedence/priority of operators to do the thing in accurate way. Therefore I've created the operator precedence table to provide you the easy way to understand the things.

Operator Precedence Table

Note - Operator at top row has the highest precedence. Whereas operator at bottom (last) row has the lowest precedence.

For example, operators at 3rd row has higher precedence than operators at 4th row but lower precedence than operators at 2nd row. Similarly operators at 8th row has higher precedence than operators at 9th row but lower precedence than operators at 7th row

Operator Name Syntax Precedence
** Exponent a ** b Highest Precedence
+, -, ˜ Unary Plus, Unary Minus, Bitwise NOT +a, -a, ˜a
*, /, //, % Multiplication, Division, Floor division, Modulus a*b, a/b, a//b, a%b
+, - Addition, Subtraction a + b, a - b
<<, >> Bitwise Left Shift, Bitwise Right Shift a << 2, a>>3
& Bitwise AND a & b
| Bitwise OR a | b
^ Bitwise XOR a ^ b
==, !=, >, >=, <, <= Comparison Operators a == b, a != b, a > b, a < b, a >= b, a <= b
is, is not Identity Operators a is b, a is not b
in, not in Membership Operators element in a, element not in a
not Logical NOT not(a > b)
and Logical AND a > b and a < c
or Logical OR a > b or a < c Lowest Precedence

Here is an example shows how the precedence of operator decides the priority of operation to be evaluate in an expression:

a, b, c, d = 2, 3, 4, 5
res = a + b ** c / d
print(res)

The output produced by above program is shown in the snapshot given below:

python operator precedence example

From above example program, the expression gets evaluated in this way:

  a + b ** c / d
= a + 3 ** 4 / d
= a + 81 / d
= a + 81 / 5
= a + 16.2
= 2 + 16.2
= 18.2

I've not taken some of the operators in the expression given above, because if I do so, then the final answer will be in the form of True/False. Therefore to create a more understandable expression, I've done the things as shown above. Now the expression given below uses most categories of operator. But before evaluating the expression, the statement given below:

a, b, c, d, e, f = 2, 3, 4, 5, 6, 7

initializes 2 to a, 3 to b, 4 to c, 5 to d, 6 to e, and 7 to f. That is, a = 2, b = 3, c = 4, d = 5, e = 6, and f = 7. Now let's evaluate the expression based on these variables:

  a + b // c ** d != e is not f
= a + b // 4 ** 5 != e is not f
= a + b // 1024 != e is not f
= a + 3 // 1024 != e is not f
= a + 0 != e is not f
= 2 + 0 != e is not f
= 2 != e is not f
= 2 != 6 is not f
= True is not f
= True is not 7
= True

Therefore, True is the final output, you'll see after evaluating the above expression one by one with keeping operator precedence in mind.

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