Deck 11: Simulation:computer Simulation Using Objects

Question 1

Computer simulations use ____ as a way of introducing some realistic variability into the underlying model.

A) relationships
B) random numbers
C) algorithms
D) classes

Answer 1

B

Question 2

In the bears and fish simulation presented in your text, if a fish has two or more adjacent fish, it will:

A) die.
B) breed.
C) turn into a bear.
D) eat.

Answer 2

A

Question 3

When transforming a problem into program code, ____ become objects.

A) verbs
B) classes
C) adjectives
D) nouns

Answer 3

D

Question 4

When transforming a problem into program code, what should you use to define the instance variables of an object?

A) The things the object should know
B) The things the object should do
C) The things an object is related to
D) The name of the object

Question 5

Assume a list g exists. When using row major order representing a grid, how do you access an item at location (x, y) in g?

A) g[y][x]
B) g[x][y]
C) g[x+y]
D) g[x*y]

Question 6

To create a grid using row major order, first create a row by repeatedly appending ____ to an empty list.

A) []
B) None
C) row
D) 0

Question 7

The freezeWorld method of a simulation calls the ____ method of wscreen to allow the graphics window to remain drawn after the simulation has ended.

A) quit
B) stop
C) exitonclick
D) exit

Question 8

Case Study 1:
1. class Fish:
2. def __init__(self):
3. self.__turtle = turtle.Turtle ()
4. self.__turtle.up()
5. ??????
6. self.__turtle.shape(""Fish. g i f"")
7.
8. self.__xPos = 0
9. self.__yPos = 0
10. self.__world = None
11.
12. self.__breedTick = 0
-Refer to the session in the accompanying Case Study 1. What does this code represent?

A) The constructor for a simulation
B) The constructor for World
C) The constructor for Fish
D) The definition for Fish

Question 9

Case Study 1:
1. class Fish:
2. def __init__(self):
3. self.__turtle = turtle.Turtle ()
4. self.__turtle.up()
5. ??????
6. self.__turtle.shape(""Fish. g i f"")
7.
8. self.__xPos = 0
9. self.__yPos = 0
10. self.__world = None
11.
12. self.__breedTick = 0
-Refer to the session in the accompanying Case Study 1. What belongs on line 5?

A) self.turtle.pos = (0,0)
B) hideturtle ()
C) turtle.hide ()
D) self.turtle.hideturtle ()

Question 10

Consider the bears and fish simulation presented in your text. Imagine that a fish is at location (x, y) and squares are drawn all around it in two dimensions. What are the coordinates for the location that is immediately above the fish in the previous row?

A) (x - 1, y + 1)
B) (x + 0, y + 1)
C) (x - 1, y + 0)
D) (x + 1, y + 0)

Question 11

What built-in function asks if an object is an instance of a particular class?

A) is
B) instanceof
C) isinstance
D) getclass

Question 12

Case Study 2:
1. def liveALittle(self):
2. self.__breedTick = self.__breedTick + 1
3. ??????
4. self.tryToBreed()
5.
6. self.tryToEat()
7.
8. if self.__starveTick == 10:
9. self.__world.delThing(self)
10. else:
11. ??????
-Refer to the session in the accompanying Case Study 2, which shows the liveALittle method for the Bear class. What belongs on line 3?

A) if self.__breedTick >= 8:
B) if self.__breedTick &It; 8:
C) if self == "Bear":
D) if self.__currentPosition > 1:

Question 13

Case Study 2:
1. def liveALittle(self):
2. self.__breedTick = self.__breedTick + 1
3. ??????
4. self.tryToBreed()
5.
6. self.tryToEat()
7.
8. if self.__starveTick == 10:
9. self.__world.delThing(self)
10. else:
11. ??????
-Refer to the session in the accompanying Case Study 2, which shows the liveALittle method for the Bear class. What belongs on line 11?

A) world.delete()
B) fish.tryToEscape()
C) self.tryToMove()
D) world.tryToMove()

Question 14

Case Study 3:
1. def mainSimulation():
2. numberOfBears = 10
3. numberOfFish = 10
4. worldLifeTime = 2500
5. worldWidth = 50
6. worldHeight = 25
7.
8. myWorld = World(worldWidth, worldHeight)
9. myWorld.draw()
10.
11. for i in range(numberOfFish):
12. newFish = Fish()
13. x = random.randrange(myWorld.getMaxX())
14. y = random.randrange(myWorld.getMaxY())
15. while not myworld.emptyLocation(x, y):
16. x = random.randrange(myWorld.getMaxX())
17. y = random.randrange(myWorld.getMaxY())
18. myWorld.addThing(newFish, x, y)
19.
20. for i in range(numberOfBears):
21. newBear = Bear()
22. x = random.randrange(myWorld.getMaxX())
23. y = random.randrange(myWorld.getMaxY())
24. while not myWorld.emptyLocation(x, y):
25. x = random.randrange(myWorld.getMaxX())
26. y = random.randrange(myWorld.getMaxY())
27. myWorld.addThing(newBear, x, y)
28.
29. for i in range(worldLifeTime):
30. myWorld.liveALittle()
31.
32. myWorld.freezeWorld()
-Refer to the session in the accompanying Case Study 3. On what lines does most of the simulation work take place?

A) 2-9
B) 11-18
C) 20-27
D) 29-30

Question 15

As you consider the implementation for the Fish, Bear, and Plant classes, you have probably noticed that there are a number of duplications. The technique of ____ would help to solve this issue.

A) information hiding
B) simulation
C) generation
D) inheritance

Question 16

The complexity of a computer simulation is dependent on the complexity of the underlying reality as well as the specific characteristics we are interested in representing.

Question 17

In the simulation of bears and fish presented in your text, all life-forms are "alive" at the same time.

Question 18

When creating objects, the list of things that an object can do will become methods.

Question 19

Removing a life-form from a simulation world requires only that it be taken off the grid.

Question 20

The mainSimulation function creates all the life-forms that will exist during the simulation.

Question 21

Match each definition with its term.
-A programmatic model of some specific aspects of a real situation or system.

A) Computer simulation
B) Instance variables
C) Class
D) Methods

Question 22

Match each definition with its term.
-The list of things that an object should know.

A) Computer simulation
B) Instance variables
C) Class
D) Methods

Question 23

Match each definition with its term.
-Identified by nouns and used to create objects that correspond to parts of a problem.

A) Computer simulation
B) Instance variables
C) Class
D) Methods

Question 24

Match each definition with its term.
-The list of things than an object should be able to do.

A) Computer simulation
B) Instance variables
C) Class
D) Methods

Question 25

What is a computer simulation?

Question 26

Explain how to design the Python classes that will be used in a program.

Question 27

Explain how to identify the instance variables and methods that should belong to an object.

Question 28

The solution for the bears and fish simulation in your text creates a two-dimensional grid. Explain how to implement this type of grid in Python.

Question 29

Describe the move method for fish for the simulation presented in your text.

Question 30

Suppose you are working with the bear and fish simulation presented in your text, which uses a two-dimensional grid. Explain how to determine the number of fish that are next to a certain fish.

Question 31

Suppose you are working with the bear and fish simulation presented in your text, which uses a two-dimensional grid. Describe the process by which the tryToBreed method chooses a random location next to the fish.

Question 32

Consider the bears and fish simulation presented in your text. Explain how the Bear class is similar to and different from the Fish class.

Question 33

Provide a high-level overview of the bears and fish simulation by outlining the algorithm of the main function.

Question 34

Explain how you might add a Plant class to the bears and fish simulation presented in your text.