In my first semester back at The University of Queensland I learnt Python as part of a course called “Introduction to Software Engineering”. There were 3 assignments each more complex than the last.
Assignment 1
The first one was a simple command line interface tool to help solve a puzzle.
A selection of the code:
def interact():
"""
runs the app
interact() -> Null (output)
"""
userInput = ""
numOfSupporters = int(input("How many supporters from each team? "))
state = make_initial_state(numOfSupporters)
states = [state]
while str(userInput) != "q":
show_current_state(states)
userInput = input("? ")
if userInput == "b":
states.pop(-1)
if userInput != "q" and userInput != "b":
# states.append(make_move(states[-1], int(userInput)))
# while consise, the above line is hard to read - let's break it out
new_move = make_move(states[-1], int(userInput))
states.append(new_move)
Assignment 2
The second assignment served as an introduction to Object Oriented Programming and Model-View-Controller. Using the teaching staff provided GUI (View) our task was to implement the Model and some of the Controller.
class Animal(Organism):
"""
Animal class. A type of Organism
Preconditions: needs a [position (dict), time]
and name (string) when instantiating it
"""
def __init__(self, position, name, gender, tracker_id):
super().__init__(position, name)
self._gender = gender
self._tracker_id = tracker_id
self._position = position
def __str__(self):
if self._tracker_id is not "":
return TRACKER_ANIMAL_FORMAT.format(self._name,
self._gender,
self._position[-1][0][0],
self._position[-1][0][1],
time_to_time_string(self._position[-1][1]),
self.get_id(),
self._tracker_id)
else:
return BASIC_ANIMAL_FORMAT.format(self._name,
self._gender,
self._position[-1][0][0],
self._position[-1][0][1],
self.get_id())
def to_dictionary(self):
d = super().to_dictionary()
d.update({'type': 'animal', 'tracker_id': self._tracker_id,
'gender': self._gender})
return d
def get_position(self):
# print(self._position)
return self._position[-1][0]
def add_location(self, position):
self._position.append([position, time.time()])
def get_track(self):
track = []
if len(self._position) > 1:
for i, each in enumerate(self._position):
track.append(self._position[i][0])
return track
Assignment 3
The third assignment proved the most difficult, but overall rewarding. It was to build a Python implementation of a breakout-style video game using the native GUI framework, TKInter. The teaching staff provided some helper code to handle collision detection and the math-heavy speed and direction control which was beyond the scope of the exercise.
Following is a sample of the code to save the high scores when the player looses or wins.
def write_high_scores(self):
"""
writes highscores back to JSON
:return:
"""
# print(self._high_scores)
with open("highscores.json", 'w') as f:
f.write(json.dumps(self._high_scores, sort_keys=True,
indent=4, separators=(',', ':')))
def get_high_scores(self):
"""
returns just the highscores - the keys in the dict
Highscores.get_high_scores(object) -> list
"""
keyList = []
# print(list(self._high_scores.keys()))
for each in list(self._high_scores.keys()):
keyList.append(int(each))
if list(self._high_scores.keys()) != []:
return sorted(keyList, reverse=True)
else:
return ["0"]
def get_lowest_score(self):
"""
retuns the lowest score as an int
Highscores.get_lowest_score(object) -> int
Precondition: assuming the result of get_high_scores is list of ints
:return:
"""
return int(self.get_high_scores()[-1])
def is_score_already_high(self):
"""
Returns true is score in list
:return:
"""
if self._score in self.get_high_scores():
return True
else:
return False
def add_score(self, score, name):
"""
adds score to dictionary of highscores
Highscores.add_score(object, int, str)
Preconditions self._high_scores can only ever have 6, hopefully
"""
self._high_scores[score] = name
if len(self.get_high_scores()) > 5:
self._high_scores.pop(str(self.get_high_scores()[-1]))
def name_prompt(self):
"""
asks for name
Highscore.name_prompt(object) -> str
:return:
"""
name = tk.simpledialog.askstring("You Got a High Score!",
"Enter Your Name: ")
if name is None or name == "":
name = "Anon"
return name
def show_high_scores(self):
"""
shows the actual highscores in a dialog
:return:
"""
if len(self._high_scores) > 0:
highscores_string = ""
for each in self.get_high_scores():
highscores_string += \
HIGHSCORE_FORMAT.format(each, self._high_scores[str(each)])
else:
highscores_string = "No scores at all yet. Keep playing!"
messagebox.showinfo("Highscores", highscores_string)
def highscores(self, score):
"""
does highscore stuff
Preconditions: max length of high scores dict is 5
:param score:
:return:
"""
self._score = score
# print(self.is_score_already_high(), self.get_lowest_score())
# score already high - skip following code block
if not self.is_score_already_high():
# then check the leaderboard isn't full
if (len(self._high_scores) == 5 and
score > int(self.get_lowest_score()) or
(len(self._high_scores) < 5)):
name = self.name_prompt()
self.add_score(str(score), name)
# print(self._high_scores)
self.write_high_scores()
# self.show_high_scores()
self.show_high_scores()
# print("exiting")