ps6.py

# Problem Set 6: Simulating robots
# Name:
# Collaborators:
# Time:

import math
import random

import ps6_visualize
import pylab

# === Provided classes

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: float 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()
        # 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 __eq__(self, pos):
        if self.getX() == pos.getX() and self.getY() == pos.getY():
            return True
        else:
            return False

# === Problems 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 = int(width)
        self.height = int(height)

        # Tiles are a list of positions
        self.tiles = []
        for i in range(self.width):
            for j in range(self.height):
                self.tiles.append(Position(i,j))

        self.dirty_tiles = self.tiles[:]

#    # I'm a dirty, dirty whore
#    def addTile(self, x, y):
#        self.tiles.append(Position(x,y))

    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
        """
        x = math.floor(pos.getX())
        y = math.floor(pos.getY())
        tile_pos = Position(x,y)
        if tile_pos in self.dirty_tiles:
            self.dirty_tiles.remove(tile_pos)

    def tileList(self, tiles):
        tiles_list = []
        for t in tiles:
            tiles_list.append(str(t.getX())+","+str(t.getY()))
        return tiles_list


    def getDirtyTiles(self):
        """
        Returns a list of dirty tiles
        """
        return self.tileList(self.dirty_tiles)


    def getCleanTiles(self):
        clean_tiles = self.tiles[:]
        for tile in self.dirty_tiles:
            clean_tiles.remove(tile)
        return self.tileList(clean_tiles)

    def isTileCleaned(self, pos):
        """
        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
        """
        #is_clean = Position(m, n)
        x = math.floor(pos.getX())
        y = math.floor(pos.getY())
        tile_pos = Position(x,y)
        return tile_pos not in self.dirty_tiles

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

        returns: an integer
        """
        return len(self.tiles)

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

        returns: an integer
        """
        return len(self.tiles) - len(self.dirty_tiles)

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

        returns: a Position object.
        """
        return self.tiles[random.randint(0,len(self.tiles))]

    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.
        """
        # Check for position out of rectangle bounds
        #if pos.getX() > self.width or pos.getY() > self.height:
        #    return False
        #if pos.getX() < 0 or pos.getY() < 0:
        #    return False
        #return True
        return ((0 <= pos.getX() < self.width) and (0 <= pos.getY() < self.height))


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, name="Little Jimmy"):
        """
        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.name = name
        self.room = room
        self.speed = float(speed)
        self.position = Position(0,0)
        self.direction = random.randint(0,359)

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

        returns: a Position object giving the robot's position.
        """
        return self.position

    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

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

        position: a Position object.
        """
        self.position = position

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

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

    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.
        """
        raise NotImplementedError


## === 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 hits a wall, it chooses a new direction randomly.
    """
    def updatePositionAndClean(self):
        """
        Simulate the passage of a single time-step.

        Move the robot to a new position and mark the tile it is on as having
        been cleaned.
        """

        move_position = self.position.getNewPosition(self.direction, self.speed)
        if self.room.isPositionInRoom(move_position):
            self.setRobotPosition(move_position)
            if not self.room.isTileCleaned(self.position):
                self.room.cleanTileAtPosition(self.position)
        else:
            self.setRobotDirection(random.randint(0,359))

class RandomWalkRobot(Robot):
    """
    A RandomWalkRobot is a robot with the "random walk" movement strategy: it
    chooses a new direction at random after each time-step.
    """
    def updatePositionAndClean(self):
        """
        Simulate the passage of a single time-step.

        Move the robot to a new position and mark the tile it is on as having
        been cleaned.
        """
        cur_pos = self.getRobotPosition()
        cur_dir = self.getRobotDirection()
        self.setRobotDirection(random.randrange(360))
        new_pos = cur_pos.getNewPosition(cur_dir, self.speed)
        if self.room.isPositionInRoom(new_pos):
            self.setRobotPosition(new_pos)
            self.room.cleanTileAtPosition(new_pos)

## === Problem 3
def runSimulation(num_robots, speed, width, height, min_coverage, num_trials,
                  robot_type, vflag=False):
    """
    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. Robot or
                RandomWalkRobot)
    """
    sim_room = RectangularRoom(width, height)
    robot_hive = []
    time_steps = 0
    robot_id = 1000

    for trial in range(num_trials):
        if vflag:
            anim = ps6_visualize.RobotVisualization(num_robots, width, height)

        for robot in range(num_robots):
            robot_hive.append(robot_type(sim_room, speed, "jimmy-"+str(robot_id)))
            robot_id += 1

        while (sim_room.getNumCleanedTiles()/float(sim_room.getNumTiles())) < min_coverage:
            for robot in robot_hive:
                robot.updatePositionAndClean()
            time_steps += 1

            if vflag:
               anim.update(sim_room, robot_hive)

        if vflag:
            anim.done()
    return time_steps / num_trials



## === Problem 4
##
## 1) How long does it take to clean 80% of a 20x20 room with each of 1-10 robots?
##
## 2. how long doesn it take two robots to clean 80% or rooms with dimensions
##       20x20, 25x16, 40x10, 50x8, and 100x4?

def showPlot1(title, x_label, y_label):
    """
    Produces a plot showing dependence of cleaning time on number of robots.
    """
    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, 100, StandardRobot, True))
        times2.append(runSimulation(num_robots, 1.0, 20, 20, 0.8, 20, RandomWalkRobot, True))
    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():
#    """
#    Produces a plot showing dependence of cleaning time on room shape.
#    """
#    raise NotImplementedError

## === Problem 5
#
#class RandomWalkRobot(Robot):
#    """
#    A RandomWalkRobot is a robot with the "random walk" movement strategy: it
#    chooses a new direction at random after each time-step.
#    """
#    raise NotImplementedError
#
#
## === Problem 6
#
## For the parameters tested below (cleaning 80% of a 20x20 square room),
## RandomWalkRobots take approximately twice as long to clean the same room as
## StandardRobots do.
#def showPlot3():
#    """
#    Produces a plot comparing the two robot strategies.
#    """
#    raise NotImplementedError