Question

Question 2: Virus Wars A popular subgenre of strategy game is the so-called Virus War format, where the player is shown a field of cells, each with a virus count, and may attack other cells within a certain range. We are going to write some classes in Python to implement a simple Virus Wars game. 2a) The position class (9 points) Everything within this game is going to require a position, so it makes sense to define it up front. Define a class Position, with the following fields: • x (float) -> an x coordinate, must be initialized. • y (float) ->a y coordinate, must be initialized. • dx (float) -> a destination x co-ordinate, initialized to zero. dy (float) -> a destination y co-ordinate, initialized to zero. speed (float) -> determines rate of movement, must be initialized. The speed cannot be negative. Raise a ValueError if the speed is provided as a negative number Define the following methods, in addition to init. • move To - takes an x and a y co-ordinate, and sets them to the values of dx and dy respectively. tick - simulates one "second" of simulation time. During a tick, if dx and dy are different than x and y, move x and y towards the values of dx and dy by the value of speed. If x or y are less than speed distance away from dx or dy respectively, set the value of x or y to dx or dy. • distance - takes self and other, calculates the euclidan distance between self and other using pythagorean theorem. In [ ]: #your solution for question 2a here In [ ]: # You are encouraged to design some of your own test cases here. In [ ]: * Visible Test for Position created correctly (1 point) p = Position (5, -5, 0.5) assert(p.x == 5 and p.y == -5 and p.dx == 0 and p.dy == 0 and p.speed == 0.5) In [ ]: #Semi-Hidden Test for Position updates correctly (1 point) # you'll know if you got it right, but have to reread the question carefully to figure out what you're doing wrong - mocion 21 14

Answer 1

Position class:

import math

class Position:

    def __init__(self, x, y, speed):

        self.x = x

        self.y = y

        self.dx = 0.0

        self.dy = 0.0

        if speed < 0:

            raise ValueError('Speed cannot be negative')

        else:

            self.speed = speed

   

    def moveTo(self):

        self.x = self.dx

        self.y = self.dy

   

    def tick(self):

        if self.dx != self.x

            if pow((self.dx - self.x), 2) > pow(self.speed, 2):

                if self.dx > self.x

                    self.x = self.x + self.speed

                else:

                    self.x = self.x - self.speed

                   

        if self.dy != self.y

            if pow((self.dy - self.y), 2) > pow(self.speed, 2):

                if self.dy > self.y

                    self.y = self.y + self.speed

                else:

                    self.y = self.y - self.speed

                   

    def distance(self, other):

        return math.sqrt(math.pow((self.x - other.x), 2) + math.pow((self.y - other.y), 2))

import math Fclass Position: definit__(self, x, y, speed): self.x = x self.y = y self. dx = 0.0 self.dy = 0.0 if speed < 0: raise ValueError('Speed cannot be negative') else: self.speed = speed def moveTo (self): self.x = self.dx self.y = self.dy def tick (self): if self.dx != self.x if pow((self.dx - self.x), 2) > pow (self.speed, 2): if self. dx > self.x self.x = self.x + self.speed else: self.x = self.x - self.speed if self.dy != self.y if pow((self.dy - self.y), 2) > pow (self. speed, 2): if self.dy > self.y self.y = self.y + self.speed else: self.y = self.y - self.speed def distance (self, other): return math.sqrt (math.pow ((self.x - other.x), 2) + math.pow ((self. y - other.y), 2))

Function Tests:

In [1]: import math class Position: definit__(self, x, y, speed): self.x = x self.y = y self.dx = 0.0 self.dy = 0.0 if speed < 0 : raise ValueError('Speed cannot be negative') else: self.speed = speed def moveTo(self): self.x = self.dx self.y = self.dy def tick(self): if self.dx != self.x: if pow((self.dx - self.x), 2) > pow(self.speed, 2): if self.dx > self.x: self.x = self.x = self.speed else: self.x = self.x - self.speed if self.dy != self.y: if pow((self.dy - self.y), 2) > pow(self.speed, 2): if self.dy > self.y: self.y = self.y + self.speed else: self.y = self.y - self.speed def distance(self, other): return math.sqrt(math.pow((self.x - other.x), 2) + math.pow((self.y - other.y), 2)) In [2]: p = Position(5.5, -5.5, 0.5) p.tick) print('p.x = ' + str(p.x) + ' p.dx = ' + str(p.dx)) print('p.y = ' + str(p.y) + ' p.dy = ' + str(p.dy)) p.x = 5.0 p.dx = 0.0 p.y = -5.0 p.dy = 0.0 In [3]: 9 = Position(0, 0, -0.5) - - - - - - - ValueError Traceback (most recent call last) <ipython-input-3-d25e53dfd551> in <module> ----> 1 q = Position(0, 0, -0.5) 00 <ipython-input-1-401cc8a0748c> in init__(self, x, y, speed) self.dy = 0.0 if speed < 0: ---> 10 raise ValueError('Speed cannot be negative') 11 else: self.speed = speed ValueError: Speed cannot be negative In [ ]: 9 = Position(-3, 3, 0.5) q.distance(p) In [ ]: p.moveTo() print('p.x = ' + str(p.x) + 'p.dx = ' + str(p.dx)) print('p.y = ' + str(p.y) + 'p.dy = ' + str(p.dy))