DV Module 2 Variables, Comments & Input operators

Question 1

Things to avoid when making variable names

Answer 1

avoid using reserved Keywords and Functions as they are PREDEFINED

avoid caps in the middle of the name

avoid variable name being so long that it would lead to errors in typing it

avoid anything other then _ as they will not work with naming variables

Question 2

What is known as the assignment operator?

Answer 2

=

Question 3

can one assign the same variable with the new value

Code:
var = 100
var = 200 + 300
print(var)
Output ?

Answer 3

Seeing a record like that, a mathematician would probably protest - no value may be equal to itself plus one. This is a contradiction. But Python treats the sign = not as equal to, but as assign a value.

output: 500

Question 4

How would a shortcut operator look with this examples

1. i = i + 2 * j
2. var = var / 2
3. rem = rem % 10
4. j = j - (i + var + rem)
5. x = x ** 2

Answer 4

1. i += 2 * j
2. var /= 2
3. rem %= 10
4. j -= (i + var + rem)
5. x **= 2

Question 5

Exercise

What is the output of the following snippet?

var = 2
var = 3
print(var)

Answer 5

3

Question 6

Exercise

Which of the following variable names are wrong in Python?

my_var

m

101

averylongvariablename

m101

m 101

Del

del

Answer 6

101 # incorrect (starts with a digit)

m 101 # incorrect (contains a space)

Del # incorrect (is a keyword)

Question 7

Exercise

What is the output of the following snippet?

a = ‘1’
b = “1”
print(a + b)

Answer 7

11

Question 8

Exercise

What is the output of the following snippet?

a = 6
b = 3
a /= 2 * b
print(a)

Answer 8

1.0

2 * b = 6
a = 6 → 6 / 6 = 1.0

Question 9

How do you make a comment Python

Answer 9

use a # at the start of a line

Question 10

The _____ function is able to read data entered by the user and to return the same data to the running program.

Answer 10

input ()

Question 11

Two different type casting for function input()

Answer 11

int(input()

float(input()

Question 12

What is another use for + $ * other then adding or multiplying operators?

Answer 12

adding and multiplying strings together.

Question 13

The meaning of the positional parameter is determined by its:

Position

Appearance

Name

Answer 13

Position