Introduction to Operators

Identity Operator

Reason — Python provides two special operators viz. is and is not, which are referred to as the Identity Operators. These operators are used to check whether two values are located at the same memory location or not, and results in True or False accordingly.

//

Reason — In Python, // is the floor division operator which is a valid arithmetic operator. The symbols ? is not an operator in Python and < is a comparison operator, not an arithmetic operator.

//

Reason — The floor division operator (//) performs the division but results in only the integer part of the quotient. For example, 32//6 results in 5.

float

Reason — The division operator (/) always returns the value in the float type (by default), irrespective of the data type that are being used during the operations. So, int / int will return a float.

float

Reason — When an integer value (int) is added to a float value (float), the resultant data type will always be float. So, 5 + 3.5 returns 8.5 which is of float type.

//

Reason — In Python, // is the floor division operator which is a valid arithmetic operator. The symbols ? is not an operator in Python and < is a comparison operator, not an arithmetic operator.

==

Reason — In Python, '==' is the equality operator which is a comparison or relational operator. It returns True if both the operands are equal, otherwise False. The '=' sign is an assignment operator and '//' is the floor division operator.

0

Reason — The modulus operator (%) is used to obtain the remainder when the first number is divided by the second. Here, 25 % 5 = 0 since 25 is exactly divisible by 5 leaving no remainder. As both operands are integers, the result is also an integer (0).

64

Reason — The exponentiation operator (**) results in power raised to a base. Here, m**2 means 8 raised to the power 2, which equals 8 × 8 = 64.

10.0

Reason — The division operator (/) always returns the value in the float type (by default), irrespective of the data type of the operands. So, 100/10 returns 10.0 which is of float type.

55.5

Reason — Evaluating the expression: x*y = 5*10 = 50 (int) and z/2 = 11/2 = 5.5 (float, since division always returns float). So, c = 50 + 5.5 = 55.5.

False

Reason — Evaluating the expression: 4*2 = 8 and 2**4 = 16. So, the statement becomes 8>16 which is False. In Python, Boolean values are written as True and False with capital first letter.

1. In Python, the Script mode is used to make a program file for the future purpose.
2. The single line comment is written simply by beginning a line with a hash (#) character.
3. By default, Python program file is saved in the system with the extension .py
4. Expression refers to as a set of variables, constants and operators used together to obtain a meaningful result.
5. By default, the input( ) function accepts the data as a string
6. The operators used to compare two or more statements, known as comparison (relational) operators.
7. The modulus (%) operator is used to find remainder when a number is divided by other.
8. The comments are referred to as the non-executable statements.

Both A and R are true and R is the correct explanation of A.

Reason — Comments are non-executable statements that help users understand the programming logic, especially when developed by someone else. In Python, comments start with a # (hash) sign and can be positioned at the beginning, along with statements, or at the end of a line. The Python interpreter ignores them while executing the code. Hence, R correctly explains A.

2, 135, 5, 5.4

Reason — Evaluating each expression:

(i) 27%5 = 2 (remainder when 27 is divided by 5)

(ii) 27*5 = 135 (multiplication)

(iii) 27//5 = 5 (floor division, only the integer part of the quotient)

(iv) 27/5 = 5.4 (division always returns float)

mm = int(input("Enter length of rod in mm:"))
cm = mm / 10
m = mm / 1000
print(cm, "cm")
print(m, "meter")

Enter length of rod in mm:24568
2456.8 cm
24.568 meter

a = int(input("Enter first number:"))
b = int(input("Enter second number:"))
c = a
a = b
b = c
print("After swapping:")
print("a =", a)
print("b =", b)

Enter first number:55
Enter second number:71
After swapping:
a = 71
b = 55

a = int(input("Enter first number:"))
b = int(input("Enter second number:"))
c = int(input("Enter third number:"))
s = a + b
p = b * c
print("Sum =", a, "+", b, "=", s)
print("Product =", b, "*", c, "=", p)

Enter first number:45
Enter second number:80
Enter third number:72
Sum = 45 + 80 = 125
Product = 80 * 72 = 5760

l = float(input("Enter length of rectangle:"))
b = float(input("Enter breadth of rectangle:"))
area = l * b
perimeter = 2 * (l + b)
print("Area of rectangle =", area)
print("Perimeter of rectangle =", perimeter)

Enter length of rectangle:9
Enter breadth of rectangle:5
Area of rectangle = 45.0
Perimeter of rectangle = 28.0

b = float(input("Enter base of triangle:"))
h = float(input("Enter height of triangle:"))
area = (1/2) * b * h
print("Area of triangle =", area)

Enter base of triangle:12
Enter height of triangle:6
Area of triangle = 36.0

t = int(input("Enter time in seconds:"))
hrs = t // 3600
rem = t % 3600
mins = rem // 60
secs = rem % 60
print(hrs, "hrs.", mins, "min.", secs, "sec.")

Enter time in seconds:8730
2 hrs. 25 min. 30 sec.

a = int(input("Enter first number:"))
b = int(input("Enter second number:"))
c = int(input("Enter third number:"))
n1 = a + b
n2 = b + c
n3 = c + a
print("After swapping:")
print("First number =", a, "+", b, "=", n1)
print("Second number =", b, "+", c, "=", n2)
print("Third number =", c, "+", a, "=", n3)

Enter first number:5
Enter second number:12
Enter third number:18
After swapping:
First number = 5 + 12 = 17
Second number = 12 + 18 = 30
Third number = 18 + 5 = 23

p = float(input("Enter principal amount: "))
r = float(input("Enter rate of interest: "))

i1 = (p * r) / 100
a1 = p + i1

i2 = (a1 * r) / 100
a2 = a1 + i2

i3 = (a2 * r) / 100
a3 = a2 + i3

print("Interest for the first year: ₹", i1)
print("Interest for the second year: ₹", i2)
print("Interest for the third year: ₹", i3)
print("Amount after three years: ₹", a3)

Enter principal amount: 5000
Enter rate of interest: 10
Interest for the first year: ₹ 500.0
Interest for the second year: ₹ 550.0
Interest for the third year: ₹ 605.0
Amount after three years: ₹ 6655.0

An operator is a symbol or token that performs various mathematical or logical operations on operands. Python comprises a number of operators to perform various tasks.

The different types of operators used in Python are:

1. Arithmetic Operators
2. Assignment Operators
3. Comparison Operators
4. Logical Operators
5. Identity Operators
6. Membership Operators

The comparison operators compare the values of two operands and determine the relationship between them. It always returns a Boolean value (i.e., True or False).

Python provides six types of comparison operators:

1. Less than (<)
2. Greater than (>)
3. Less than or equal to (<=)
4. Greater than or equal to (>=)
5. Equal to (==)
6. Not equal to (!=)

Comments are referred to as the non-executable statements which enable the user to understand the programming logic. They are ignored by the Python interpreter while executing the code. In Python, a comment statement starts with a # (hash) sign and can be positioned either at the beginning, along with the statements or at the end of a line.

There are two ways to give comments in Python:

(a) Single Line Comment — written by beginning a line with a hash (#) character.

(b) Multiline Comment — when a comment statement using a hash (#) character is expressed in multiple lines.

The purpose of giving comment in a program is to enable the user to understand the programming logic. Comments mention the purpose and action being taken in different steps, especially when somebody else has developed the program.

The use of input statement ensures the interaction or communication with the user. Python language provides the input() function for reading data from the standard input device (i.e., keyboard). This system provides a user-friendly environment to input data values, and the user may have the option to change the data values during the next execution of the program. Without input(), values must be assigned within the code itself, making the program restricted to those specific values. By default, the input() function returns a String type value.

Syntax: variable = input(<"Message"><Prompt>)

(a) Arithmetic Operator — The operators which are used to perform arithmetical calculations in a program are known as arithmetic operators. These include addition (+), subtraction (-), multiplication (*), division (/), floor division (//), modulus (%) and exponentiation (**).

(b) Logical Operator — Python language provides three logical operators namely and, or and not. These operators yield True or False depending upon the outcome of different conditions.

(c) Identity Operator — Identity operators are the operators which are used to compare the memory location of two objects. Python provides two special operators viz. is and is not.

(d) Membership Operator — There are two operators viz. in and not in which are said to be the Membership Operators. These operators are used to test whether a variable or value is an element of a sequence (i.e., string, list, tuple or dictionary) or not.

No, 24.0/5 and 24.0//5 will not produce the same result.

• 24.0/5 results in 4.8 — The '/' operator is known as the floating point division operator. It provides the complete result of the division including the digits after the decimal point. Therefore, it returns a float value.

• 24.0//5 results in 4.0 — The '//' operator is known as the floor division or integer division operator. It returns only the integer part of the quotient.

Thus, although both involve division by 5, the '/' operator gives the exact division (4.8), while '//' gives only the integer part of the quotient (4.0).

(a) 'sum=12' and 'sum==12' are different because:

• sum=12 uses the assignment operator (=) which assigns the value 12 to the variable 'sum'. After this statement, the variable sum holds the value 12.

• sum==12 uses the comparison operator (==) which compares the value of the variable 'sum' with 12. It returns True if sum is equal to 12, otherwise False.

(b) print(a *is* b) results in False because:

The is operator is an Identity Operator that checks whether two variables point to the same memory location (i.e., the same object), not whether their values are equal. Although both a and b have the same value (12.65), they are stored at different memory locations in memory when assigned separately as float values. Hence, the is operator returns False since they are different objects in memory, even though their values are identical.