Module 1

Exercise 1a

import draw_infinity
image = draw_infinity.make_figure()

Exercise 1b

#What is 2 to the power 15?
import math as m

print(2**15)
print(m.pow(2,15))
print("-----------")


#Convert `"It was the best of times"` to uppercase.
target = "It was the best of times"
print(target.upper())
print("It was the best of times".upper())
print("-----------")


#Sort the list `[10, 9, 0, 20, 8, 2, 30, 7, 3]`.
target = [10, 9, 0, 20, 8, 2, 30, 7, 3]
print(sorted(target)) # Returns a new list that is sorted
target.sort()  # N/B .sort() modifes the original list
print(target) 
print("-----------")


#What is 100! ? (That is, what is the factorial of 100?) Hint: the `factorial` function is in the `math` library m
print(m.factorial(100))

# Could do it my hand too but there are functions to do it in the math (and other) libraries
answer = 1
for i in range(1, 100):
    answer *= i
    
print(answer)

32768
32768.0
-----------
IT WAS THE BEST OF TIMES
IT WAS THE BEST OF TIMES
-----------
[0, 2, 3, 7, 8, 9, 10, 20, 30]
[0, 2, 3, 7, 8, 9, 10, 20, 30]
-----------
93326215443944152681699238856266700490715968264381621468592963895217599993229915608941463976156518286253697920827223758251185210916864000000000000000000000000
933262154439441526816992388562667004907159682643816214685929638952175999932299156089414639761565182862536979208272237582511852109168640000000000000000000000

A note about sorted and sort.

sorted(target)

returns a new list that is sorted

target.sort()

modifies the original list. If we look at their positions in memory we can verify this:

example_list = [3, 8, 1, 0, 5, 8, 9, 1, 1, 5]
print(f"Example list = {example_list}")
print(hex(id(example_list))) # Where the example list is stored
print("")
new_list = sorted(example_list)
print(f"New list     = {new_list}")
print(hex(id(new_list))) # Where the new list is stored
print(f"Example list = {example_list}")
print(hex(id(example_list))) # Where the example list is stored
print("")
example_list.sort()
print(f"Example list = {example_list}")
print(hex(id(example_list))) # Where the (sorted) example list is stored

Example list = [3, 8, 1, 0, 5, 8, 9, 1, 1, 5]
0x7fcd98073940

New list     = [0, 1, 1, 1, 3, 5, 5, 8, 8, 9]
0x7fcd98077d80
Example list = [3, 8, 1, 0, 5, 8, 9, 1, 1, 5]
0x7fcd98073940

Example list = [0, 1, 1, 1, 3, 5, 5, 8, 8, 9]
0x7fcd98073940

We can see that the example list is in the same place as it was before, but now it is sorted

Exercise 1c

# Which of the operators `+`, `-`, `*`, and `/` do something useful with the lists `[1, 10, 100]` and `[5, 4, 7]`?
a = [1, 10, 100]
b = [5, 4, 7]
print(a+b)
# all others not allowed
print("")

# What happens if you apply the operators `+`, `-`, `*`, `/` to a list and a number?
c = [1, 2, 3, 4, 'five']
d = 2
print(c*d)
# all others not allowed
print("")


# What about a string and a string?
e = "string-1"
f = "string-2"
print(e + f)
# all others not allowed

[1, 10, 100, 5, 4, 7]

[1, 2, 3, 4, 'five', 1, 2, 3, 4, 'five']

string-1string-2

Exercise 1d

Something with a similar structure to this:

house = {
    "living": {
        "exits": {"north": "kitchen", "outside": "garden", "upstairs": "bedroom"},
        "people": ["James"],
        "capacity": 2,
    },
    "kitchen": {"exits": {"south": "living"}, "people": [], "capacity": 1},
    "garden": {"exits": {"inside": "living"}, "people": ["Sue"], "capacity": 3},
    "bedroom": {
        "exits": {"downstairs": "living", "jump": "garden"},
        "people": [],
        "capacity": 1,
    },
}

Some important points about this particular solution:

• The whole solution is a single nested structure.

• Indentation is used to make the structure easier to read.

• Python allows code to continue over multiple lines, so long as sets of brackets are not finished.

• There is an empty person list in empty rooms, so the type structure is robust to potential movements of people.

• We are nesting dictionaries and lists, with string and integer data.

Exercise 1e

We can count the occupants and capacity like this:

capacity = 0
occupancy = 0
for name, room in house.items():
    capacity += room["capacity"]
    occupancy += len(room["people"])
print(f"House can fit {capacity} people, and currently has: {occupancy}.")

House can fit 7 people, and currently has: 2.

As a side note, note how we included the values of capacity and occupancy in the last line. This is a handy syntax for building strings that contain the values of variables. You can read more about it here or in the official documentation for formatted string literals; f-strings.