Python Tutorial #7 | Operators

Operator is anything which acts on operands and produces a result.

a = b + 5

In the above statement, '=' and '+' are operators, 'a' and 'b' are variables and '5' is a constant. Together, 'a', 'b' '5' are called operands. '=' is called an assignment operator as it assignes 'b + 5' to 'a'. In computer science, the assignment is always from right to left i.e. in case of an assignment, the right expression is computed and is assigned to left expression. Expression is a combination of operators and operands.

Operation on strings

'+' operator is used to add two or more strings.

a = "Electronics Revealed"
b = "The biggest online portal"
c = a + b

Now 'c' will contain 'InternshalaThe biggest internship portal'. A key thing to note here is that, with '+' operator, two strings are just concatenated (added) without any extra spaces being introduced.
'*' operator is used to replicate the string.

d = "Revealed"
e = d*3
print (e)

The output for the above case will be 'RevealedRevealedRevealed'. '*' is very useful if string replication is needed.

Operation on numbers

The basic operations on numbers are addition, subtraction, multiplication and divison.

a = 6
b = 5
print (a + b)
print (a - b)
print (a * b)
print (a / b)

---

11
1
30
1.2

Sometimes, we just want to get an integer value even after divison. In that case '//'' operator is used to divide two numbers, and return an integer value. This is called integer divison.

NOTE: '//' operation is generally used in divison of two integers.
As stated before if a user enters a number, it is considered as a string. So, we need to change it from string to real number.

l = float(input('Enter a floating number : '))
m = int(input('Enter an integer : '))

If a real number needs to be converted to a string, str() function is used.

a = 5.2
s = str(a)

To see what data type a variable is, type() function is used.

k = 5.27
print (type(k))

Note: All data types are not interconvertible. If in a string, there are some alphabets and you convert it to an integer, an error will be returned.

Operator Precedence Table

Operator	Description
lambda	Lambda Expression
or	Boolean OR
and	Boolean AND
not x	Boolean NOT
in, not in	Membership tests
is, is not	Identity tests
<, <=, >, >=, !=, ==	Comparisons
|	Bitwise OR
^	Bitwise XOR
&	Bitwise AND
<<, >>	Shifts
+, -	Addition and subtraction
*, /, %	Multiplication, Division and Remainder
+x, -x	Positive, Negative
~x	Bitwise NOT
**	Exponentiation

Operators with the same same precedence are listed in the same row in the above table. For example, + and - have the same precedence.