Operator precedence in python with examples
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The following table lists all operators from highest precedence to lowest. Show
Operator precedence affects how an expression is evaluated. For example, x = 7 + 3 * 2; here, x is assigned 13, not 20 because operator * has higher precedence than +, so it first multiplies 3*2 and then adds into 7. Here, operators with the highest precedence appear at the top of the table, those with the lowest appear at the bottom. Example#!/usr/bin/python a = 20 b = 10 c = 15 d = 5 e = 0 e = (a + b) * c / d #( 30 * 15 ) / 5 print "Value of (a + b) * c / d is ", e e = ((a + b) * c) / d # (30 * 15 ) / 5 print "Value of ((a + b) * c) / d is ", e e = (a + b) * (c / d); # (30) * (15/5) print "Value of (a + b) * (c / d) is ", e e = a + (b * c) / d; # 20 + (150/5) print "Value of a + (b * c) / d is ", e When you execute the above program, it produces the following result − Value of (a + b) * c / d is 90 Value of ((a + b) * c) / d is 90 Value of (a + b) * (c / d) is 90 Value of a + (b * c) / d is 50 python_basic_operators.htm OverviewOperator precedence in Python simply refers to the order of operations. Operators are used to perform operations on variables and values. Python classifies its operators in the following groups:
Arithmetic OperatorsCommon arithmetic operators in Python include:
Order of operationsThe order of operations of the arithmetic operators can be remembered using the acronym BEDMAS. The acronym stands for the following words, which tell us which operator comes first:
Through the acronym, we can see that the bracket/parenthesis operator comes before the exponentiation operation in Python, according to the order of operations. The same logic applies to each of the following operators, down to the subtraction operator. ExampleTo fully grasp BEDMAS and the order of preference of the operators, let’s take a look at the example below: X = (5 + 3) * 2 ** 2 print(X) From this program, we can see that there are three operators:
According to operator precedence, Python first deals with the numbers in the bracket operator (B): We then proceed to the exponentiation operator (E): Finally, the results of both the bracket ( In short, Python followed the order of operators outlined in BEDMAS. ExampleThe same logic applies to the examples below: x = 3 + 8 * 2** 3 print(x) y= (4 * 2) + 6 / 3 - 2 print(y) The value of Assignment OperatorsCommon assignment operators in Python include:
Order of operationSince these operators are not associative, there is no order of operation for them. They are always performed or declared exclusively. Example# using the assigm operator x = 6 y = 2 # to generate the Add AND operator i.e x + y = 8 x += y print(x) # to generate the subtract AND operator i.e x - y = 8 - 2 = 6 x -= y print(x) # to generate the multiply AND ooperator i.e x * y = 6 * 2 = 12 x *= y print(x) # to generate the divide AND operator i.e x / 2 = 12 / 2 = 6 x /= y print(x) # to generate the modulo AND operator 1.e x %= 2 = 6 % 2 = 0 x %= y print(x) Comparison OperatorsComparison operators include:
Order of operationSince these operators are not associative, there is no order of operation for them. They are always performed or declared exclusively. ExampleThe program below introduces each of the comparison operators: x = 6
y = 2
if x == y:
print('x is equal to y')
else:
print('x is not equal to y')
if x != y:
print('x is not equal to y')
else:
print('x is equal to y')
if x > y:
print('x is greater than y')
else:
print('x is not greater thab y')
if x < y:
print('x is less than y')
else:
print('x is not less than y')
if x >= y:
print('x is greater than or equal to y')
else:
print('x is not greater than or equal to y')
if x <= y:
print('x is less than or equal to y')
else:
print('x is not less than or equal to y')Logical operatorsLogical operators in Python include:
Order of operationsThe order of operations for logical operators from the highest to the lowest is as follows:
# Precedence of 'or' & 'and'
name = "Theophilus"
age = 0
if name == "Theophilus" or name == "John" and age >= 2 :
print("Hello! Welcome.")
else :
print("Good Bye!!")The example above shows how the precedence of the logical Identity operatorsThe identity operators in Python include:
The order of precedence of the identity operators in Python from left to right would be: Membership operatorsThe order of precedence of the membership operators in
Python from left to right is ExampleIn the code below, we check whether or not the values of x = 2
y = 4
list = [1, 2, 3, 6, 7 ];
if ( x in list ):
print("Yes x is in the list")
else:
print("x can not be found on the list")
if ( y not in list ):
print("y is not in the given list")
else:
print("y is in the given list")The example above shows how the precedence of SummaryThe table below shows the summary of the different operator and their precedencies in python
CONTRIBUTOR What is operator precedence explain with example?The precedence of an operator specifies how "tightly" it binds two expressions together. For example, in the expression 1 + 5 * 3 , the answer is 16 and not 18 because the multiplication ("*") operator has a higher precedence than the addition ("+") operator. Parentheses may be used to force precedence, if necessary.
What is the order of precedence of operators in Python?Python follows the same precedence rules for its mathematical operators that mathematics does. Parentheses have the highest precedence and can be used to force an expression to evaluate in the order you want. Since expressions in parentheses are evaluated first, 2 * (3-1) is 4, and (1+1)**(5-2) is 8.
What is meant by operator precedence and associativity in Python?Operator Associativity: If an expression contains two or more operators with the same precedence then Operator Associativity is used to determine. It can either be Left to Right or from Right to Left.
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