Week2-4

Question 1

What does the 0:.2f mean in this code:

“Floating point {0:.2f}”.format(4.456)

Answer 1

The 2 is the number of digits to display after the decimal point.
The f means that it will be a “floating point” number (i.e. it will have a decimal.)

Question 2

What does the lowercase d mean in:

‘Sam has {1:d} red balls’

Answer 2

The number outputted will be an Integer

Question 3

What does the lowercase f mean in:

“Floating point {0:.2f}”

Answer 3

The outputted number will be a Floating Point number (i.e., a # with a decimal)

Question 4

Given this code:
‘Sam has {1:d} red balls and {0:d} yellow balls’.format(12, 31)

What will the Output be?

Answer 4

Sam has 31 red balls and 12 yellow balls

Question 5

Given:
def times(x, y):

Which one is the function?
Which one is the argument?

Answer 5

‘times’ is the function

x and y are the arguments of the function

Question 6

Given:
print(‘abc’):

Which one is the function?
Which one is the argument?

Answer 6

‘print’ is the function

‘abc’ is the function’s argument

Question 7

T/F:

Integers are immutable

Answer 7

True

Question 8

T/F:

Strings are immutable

Answer 8

True

Question 9

T/F:

Lists are immutable

Answer 9

False

Question 10

T/F:

Tuples are immutable

Answer 10

True

Question 11

T/F:

Floats are immutable

Answer 11

True. Floating numbers cannot be changed

Question 12

T/F:

Integers are mutable

Answer 12

Fals. Integers can be changed.

Question 13

What is a docstring?

Answer 13

see Week 3 HW, first question

see Week 3 lecture Notes

Question 14

What is ‘None’ in the Python language?

Answer 14

None is a ‘datatype’ in Python whose purpose to basically representing a null value, or ‘nothing’. So if your function does not have a return statement, it’ll by default return a None.

Question 15

if your function does not have a return statement, it’ll by default return a ____.

Answer 15

None (aka, NoneType)

Question 16

the None datatype is aka:

Answer 16

NoneType

Question 17

arguments are aka:

Answer 17

parameters

Question 18

List the datatypes in Python:

Answer 18

int,
float,
complex,
bool,
str,
NoneType

Question 19

Given this code/input:

> > > L = [1]
L[:0] = [2, 3, 4]
L

What is the output?

Answer 19

[2, 3, 4, 1]

Question 20

Given this code:

> > > L = [1, 2, 3]
L[1:2] = [4, 5]
L

What is the output?

Answer 20

[1, 4, 5, 3]

Question 21

Given this code:

> > > L = [1, 4, 5, 3]
L[1:1] = [6, 7]
L

What is the output?

Answer 21

[1, 6, 7, 4, 5, 3]

Question 22

Given this code/input:

> > > L = [1, 6, 7, 4, 5, 3]
L[1:2] = []
L

What is the output?

Answer 22

[1, 7, 4, 5, 3]

Question 23

Given this input:

> > > L = [‘eat’, ‘more’, ‘SPAM!’]
L.append(‘please’)
L

What is the output?

Answer 23

[‘eat’, ‘more’, ‘SPAM!’, ‘please’]

Question 24

the .sort command sorts in [ascending / descending] order

Answer 24

ascending

Question 25

Given this input:

> > > L = [‘abc’, ‘ABD’, ‘aBe’]
L.sort() # Sort with mixed case
L

What is the output?

Answer 25

[‘ABD’, ‘aBe’, ‘abc’]

Question 26

Given this input:

> > > L = [1, 2, 3, 4, 5]
L.pop()
L

What is the output?

Answer 26

[1, 2, 3, 4]

Question 27

Given this input:

> > > [1, 2, 3, 4]
L.reverse()
L

What is the output?

Answer 27

[4, 3, 2, 1]

Question 28

Give the code that is missing below:

> > > [1, 2, 3, 4]
_________
L
[4, 3, 2, 1]

Answer 28

L.reverse()

Question 29

Given this input:

> > > L = [‘spam’, ‘eggs’, ‘ham’, ‘toast’]
del L[0]
L

What is the output?

Answer 29

[‘eggs’, ‘ham’, ‘toast’]

Question 30

Given this input:

> > > L = [‘Already’, ‘got’, ‘one’]
L[1:] = []
L

What is the output?

Answer 30

[‘Already’]