Assignment 1

Question 1

Arithmetic Operations on Python

Answer 1

1) addition (+), subtraction (-), multiplication (*), division (/)
2) exponent (**)
3) integer division (//)
4) remainder (%)

Question 2

Operation on strings

Answer 2

+ or *

Question 3

Cannot add different variable types

Question 4

Variable types

Answer 4

String
Integer
Float
Boolean

Question 5

int(value)
string(value)
float(value)

Answer 5

changes value to int/string/float

Question 6

Python is case sensitive and avoid using keywords as variable names

Question 7

Relational operators?

Answer 7

<, >, <=, >=, ==, !=

Question 8

Relational operators
in, not in

Answer 8

string operators
eg: ‘app’ in ‘apples’ returns TRUE
eg: ‘bbc’ in ‘apples’ returns FALSE
eg: ‘abp’ in ‘apples’ returns FALSE

Question 9

Boolean operators

Answer 9

or
and
not

Question 10

Boolean operators precedence

Answer 10

not -> and -> or

Question 11

Precedence of ALL operators

Answer 11

()
**
+x/-x (positive/negative)
*, /, //, %
+, -
relational operators
not -> and -> or

Question 12

print() and input()

Question 13

\n

Answer 13

new line

Question 14

\t

Answer 14

tab

Question 15

\

Answer 15

inserts backslash

Question 16

", '

Answer 16

inserts ‘ or “

Question 17

\

Answer 17

used to split a long string on multiple lines

Question 18

s.upper()
s.lower()

Answer 18

returns string s in all caps or lowercase

Question 19

s.strip()

Answer 19

removes leading and trailing space

Question 20

s.count(substring)

Answer 20

returns the number of time substring occurs in s

Question 21

s.replace(old, new)

Question 22

len(s)

Answer 22

nb of characters

Question 23

s.split(‘character’, max number of items in list)

Question 24

3 Types of Error

Answer 24

Syntax, Runtime, Semantic

Question 25

Syntax Error

Answer 25

Cased by writing code that is not the correct structure or format

Question 26

Runtime Error

Answer 26

Caused by doing something that’s not allowed (e.g. subtracting strings, using not assigned variables)

Question 27

Semantic Error

Answer 27

Caused when your program does something, just not the right thing

Question 28

Error Messages

Answer 28

Parse, Type, Name, Value

Question 29

Parse Error

Answer 29

Caused by incorrect syntax

Question 30

Type Error

Answer 30

Combining value types that are not compatible
eg: string + int

Question 31

Name Error

Answer 31

typos or using an unassigned variable

Question 32

Value Error

Answer 32

using a variable that has a correct type but a problematic value

Question 33

s[first: last (excluded) : occurrence]

Answer 33

if occurrence is -x, then prints reversed

Question 34

str.format()

Answer 34

eg:
‘{} {} and {} {}’.format(‘3’, ‘oranges’, ‘5’, ‘apples’)
‘{0} {1} and {2} {3}’.format(‘3’, ‘oranges’, ‘5’, ‘apples’)
»> ‘3 oranges and 5 apples’

‘{2} {1} and {0} {3}’.format(‘3’, ‘oranges’, ‘5’, ‘apples’)
»> ‘5 oranges and 3 apples’

Question 35

str.format() -> a variable can appear multiple times

Answer 35

‘{0} {1} and {0} {1} and {2} {3}’.format(‘3’, ‘oranges’, ‘5’, ‘apples’)
»>’3 oranges and 3 oranges and 5 apples’

Question 36

str.format() -> keyword arguments

Answer 36

‘{num1} {fruit1} and {num2} {fruit2}’.format(
num2 = 5,
fruit1 = ‘apples’,
fruit2 = ‘oranges’ ,
num1 = 3)
»> ‘3 apples and 5 oranges’

Question 37

str.format() -> rounding

Answer 37

num1 = 4.674545
num2 = 6.342421
‘{num1:.1f} kg of {fruit1} and {num2:.1f} kg of {fruit2}’.format(
… num1 = num1,
… num2 = num2,
… fruit1 = ‘apples’,
… fruit2 = ‘oranges’)

> > > ‘4.8 kg of apples and 6.3 kg of oranges’

pi = 3.14159265354
f’{pi : .2f}’
»> 3.14