ps2.py

# 6.00.2x Problem Set 2: Simulating robots

import math
import random

import ps2_visualize
import pylab

# For Python 2.7:
from ps2_verify_movement27 import testRobotMovement

# If you get a "Bad magic number" ImportError, you are not using 
# Python 2.7 and using most likely Python 2.6:


# === Provided class Position
class Position(object):
    """
    A Position represents a location in a two-dimensional room.
    """
    def __init__(self, x, y):
        """
        Initializes a position with coordinates (x, y).
        """
        self.x = x
        self.y = y
        
    def getX(self):
        return self.x
    
    def getY(self):
        return self.y
    
    def getNewPosition(self, angle, speed):
        """
        Computes and returns the new Position after a single clock-tick has
        passed, with this object as the current position, and with the
        specified angle and speed.

        Does NOT test whether the returned position fits inside the room.

        angle: number representing angle in degrees, 0 <= angle < 360
        speed: positive float representing speed

        Returns: a Position object representing the new position.
        """
        old_x, old_y = self.getX(), self.getY()
        angle = float(angle)
        # Compute the change in position
        delta_y = speed * math.cos(math.radians(angle))
        delta_x = speed * math.sin(math.radians(angle))
        # Add that to the existing position
        new_x = old_x + delta_x
        new_y = old_y + delta_y
        return Position(new_x, new_y)

    def __str__(self):  
        return "(%0.2f, %0.2f)" % (self.x, self.y)


# === Problem 1
class RectangularRoom(object):
    """
    A RectangularRoom represents a rectangular region containing clean or dirty
    tiles.

    A room has a width and a height and contains (width * height) tiles. At any
    particular time, each of these tiles is either clean or dirty.
    """
    def __init__(self, width, height):
        """
        Initializes a rectangular room with the specified width and height.

        Initially, no tiles in the room have been cleaned.

        width: an integer > 0
        height: an integer > 0
        """
        self.width = width
        self.height = height
        self.cleanTile = {}
        for m in range(width):
            for n in range(height):
                self.cleanTile.setdefault((m,n), 'N')
        #raise NotImplementedError
    
    def cleanTileAtPosition(self, pos):
        """
        Mark the tile under the position POS as cleaned.

        Assumes that POS represents a valid position inside this room.

        pos: a Position
        """
        m = math.floor(pos.getX())
        n = math.floor(pos.getY())
        self.cleanTile.update({(m, n): 'Y'}) #dict.setdefault(key, default)
        #raise NotImplementedError

    def isTileCleaned(self, m, n):
        """
        Return True if the tile (m, n) has been cleaned.

        Assumes that (m, n) represents a valid tile inside the room.

        m: an integer
        n: an integer
        returns: True if (m, n) is cleaned, False otherwise
        """
        m = math.floor(m)
        n = math.floor(n)
        tile = self.cleanTile[(m, n)]
        if(tile == 'Y'):
            return True
        else:
            return False
        #raise NotImplementedError
    
    def getNumTiles(self):
        """
        Return the total number of tiles in the room.

        returns: an integer
        """
        width = self.width
        height = self.height
        total = width*height
        return(total)
        #raise NotImplementedError

    def getNumCleanedTiles(self):
        """
        Return the total number of clean tiles in the room.

        returns: an integer
        """
        width = self.width
        height = self.height
        count = 0
        for m in range(width):
            for n in range(height):
                if(self.isTileCleaned(m, n)):
                    count += 1
        return count
        #raise NotImplementedError

    def getRandomPosition(self):
        """
        Return a random position inside the room.

        returns: a Position object.
        """
        width = self.width
        height = self.height
        choice = []
        for m in range(width):
            for n in range(height):
                choice.append((m, n))
        position = random.choice(choice)
        rpos = Position(position[0], position[1])
        return(rpos)
        #raise NotImplementedError

    def isPositionInRoom(self, pos):
        """
        Return True if pos is inside the room.

        pos: a Position object.
        returns: True if pos is in the room, False otherwise.
        """
        width = self.width
        height = self.height
        m = math.floor(pos.getX())
        n = math.floor(pos.getY())
        return((0 <= m < width)and(0 <= n < height))
        #raise NotImplementedError


class Robot(object):
    """
    Represents a robot cleaning a particular room.

    At all times the robot has a particular position and direction in the room.
    The robot also has a fixed speed.

    Subclasses of Robot should provide movement strategies by implementing
    updatePositionAndClean(), which simulates a single time-step.
    """
    def __init__(self, room, speed):
        """
        Initializes a Robot with the given speed in the specified room. The
        robot initially has a random direction and a random position in the
        room. The robot cleans the tile it is on.

        room:  a RectangularRoom object.
        speed: a float (speed > 0)
        """
        self.room = room
        self.speed = speed
        self.direction = random.randrange(start=0, stop=360)
        self.position = self.room.getRandomPosition() #Position object
        #self.position = self.room.getRandomPosition() #Position object twice ???
        self.room.cleanTileAtPosition(self.position) #clean initial tile
        #raise NotImplementedError

    def getRobotPosition(self):
        """
        Return the position of the robot.

        returns: a Position object giving the robot's position.
        """
        return self.position
        #raise NotImplementedError
    
    def getRobotDirection(self):
        """
        Return the direction of the robot.

        returns: an integer d giving the direction of the robot as an angle in
        degrees, 0 <= d < 360.
        """
        return self.direction
        #raise NotImplementedError

    def setRobotPosition(self, position):
        """
        Set the position of the robot to POSITION.

        position: a Position object.
        """
        if(self.room.isPositionInRoom(position)):
            self.position = position
        else:
            self.position = self.getRobotPosition()
        #raise NotImplementedError

    def setRobotDirection(self, direction):
        """
        Set the direction of the robot to DIRECTION.

        direction: integer representing an angle in degrees
        """
        self.direction = direction
        #raise NotImplementedError

    def updatePositionAndClean(self):
        """
        Simulate the raise passage of a single time-step.

        Move the robot to a new position and mark the tile it is on as having
        been cleaned.
        """
        if(self.room.isPositionInRoom(self.position.getNewPosition(self.direction, self.speed))):
            self.position = self.position.getNewPosition(self.direction, self.speed)
        else:
            while(not self.room.isPositionInRoom(self.position.getNewPosition(self.direction, self.speed))):
                self.direction = random.randrange(start=0, stop=360)
            self.position = self.position.getNewPosition(self.direction, self.speed)       
        self.room.cleanTileAtPosition(self.position)
        #raise NotImplementedError # don't change this!


# === Problem 2
class StandardRobot(Robot):
    """
    A StandardRobot is a Robot with the standard movement strategy.

    At each time-step, a StandardRobot attempts to move in its current
    direction; when it would hit a wall, it *instead* chooses a new direction
    randomly.
    """
    def __init__(self, room, speed):
        self.speed = speed
        self.room = room
        Robot.__init__(self, self.room, self.speed)
    def updatePositionAndClean(self):
        """
        Simulate the raise passage of a single time-step.

        Move the robot to a new position and mark the tile it is on as having
        been cleaned.
        """
        Robot.updatePositionAndClean(self)
        #raise NotImplementedError

# Uncomment this line to see your implementation of StandardRobot in action!
#testRobotMovement(StandardRobot, RectangularRoom)


# === Problem 3
def runSimulation(num_robots, speed, width, height, min_coverage, num_trials,
                  robot_type):
    """
    Runs NUM_TRIALS trials of the simulation and returns the mean number of
    time-steps needed to clean the fraction MIN_COVERAGE of the room.

    The simulation is run with NUM_ROBOTS robots of type ROBOT_TYPE, each with
    speed SPEED, in a room of dimensions WIDTH x HEIGHT.

    num_robots: an int (num_robots > 0)
    speed: a float (speed > 0)
    width: an int (width > 0)
    height: an int (height > 0)
    min_coverage: a float (0 <= min_coverage <= 1.0)
    num_trials: an int (num_trials > 0)
    robot_type: class of robot to be instantiated (e.g. StandardRobot or
                RandomWalkRobot)
    """
#    #Default
#    room = RectangularRoom(width, height)
#    area = float(width*height)
#    step = []
#    move = []
#    sum_step = 0.0
#    for i in range(num_trials):
#        for j in range(num_robots):
#            move.append(robot_type(room, speed))
#        step.append(0.0)
#        while((room.getNumCleanedTiles()/area) < min_coverage):
#            for k in range(num_robots):
#                move[k].updatePositionAndClean()
#            step[i] += 1/speed
#        room.__init__(width, height) #init room
#    sum_step = sum(step)
#    return sum_step/num_trials

    
    #Visualizing Robots
    room = RectangularRoom(width, height)
    area = float(width*height)
    step = []
    robot = []
    sum_step = 0.0
    
    for i in range(num_trials):
        #step1
        anim = ps2_visualize.RobotVisualization(num_robots, width, height)
        for j in range(num_robots):
            robot.append(Robot(room, speed))
        step.append(0.0)
        while((room.getNumCleanedTiles()/area) < min_coverage):
            for k in range(num_robots):
                #step2
                anim.update(room, robot)
                robot[k].updatePositionAndClean()
            step[i] += 1/speed
        room.__init__(width, height) #init room
        #step3
        anim.done()
        
    sum_step = sum(step)
    return sum_step/num_trials

# Uncomment this line to see how much your simulation takes on average
#print  runSimulation(1, 1.0, 5, 5, 0.78, 30, StandardRobot)


# === Problem 4
class RandomWalkRobot(Robot):
    """
    A RandomWalkRobot is a robot with the "random walk" movement strategy: it
    chooses a new direction at random at the end of each time-step.
    """
    def __init__(self, room, speed):
        self.speed = speed
        self.room = room
        Robot.__init__(self, self.room, self.speed)
    def updatePositionAndClean(self):
        """
        Simulate the raise passage of a single time-step.

        Move the robot to a new position and mark the tile it is on as having
        been cleaned.
        """
        Robot.updatePositionAndClean(self)
        Robot.setRobotDirection(self, random.randrange(start=0, stop=360))  


def showPlot1(title, x_label, y_label):
    """
    What information does the plot produced by this function tell you?
    """
    num_robot_range = range(1, 11)
    times1 = []
    times2 = []
    for num_robots in num_robot_range:
        print "Plotting", num_robots, "robots..."
        times1.append(runSimulation(num_robots, 1.0, 20, 20, 0.8, 20, StandardRobot))
        times2.append(runSimulation(num_robots, 1.0, 20, 20, 0.8, 20, RandomWalkRobot))
    pylab.plot(num_robot_range, times1)
    pylab.plot(num_robot_range, times2)
    pylab.title(title)
    pylab.legend(('StandardRobot', 'RandomWalkRobot'))
    pylab.xlabel(x_label)
    pylab.ylabel(y_label)
    pylab.show()

    
def showPlot2(title, x_label, y_label):
    """
    What information does the plot produced by this function tell you?
    """
    aspect_ratios = []
    times1 = []
    times2 = []
    for width in [10, 20, 25, 50]:
        height = 300/width
        print "Plotting cleaning time for a room of width:", width, "by height:", height
        aspect_ratios.append(float(width) / height)
        times1.append(runSimulation(2, 1.0, width, height, 0.8, 200, StandardRobot))
        times2.append(runSimulation(2, 1.0, width, height, 0.8, 200, RandomWalkRobot))
    pylab.plot(aspect_ratios, times1)
    pylab.plot(aspect_ratios, times2)
    pylab.title(title)
    pylab.legend(('StandardRobot', 'RandomWalkRobot'))
    pylab.xlabel(x_label)
    pylab.ylabel(y_label)
    pylab.show()
    

# === Problem 5
#
# 1) Write a function call to showPlot1 that generates an appropriately-labeled
#     plot.
#
#       (... your call here ...)
#showPlot1('Time it takes 1-10 robots to clean 80% of a room', 'num_robot_range', 'timesteps')
#
# 2) Write a function call to showPlot2 that generates an appropriately-labeled
#     plot.
#
#       (... your call here ...)
#showPlot2('plot1', 'aspect_ratios', 'timesteps')