1.6 Game0115r review

Table of contents

• Preface
• Questions
  • 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12
• Answers
• Miscellaneous

Preface

This module contains review questions and answers keyed to the module titled GAME 2302-0115: Working with Column Matrices, Points, and Vectors .

The questions and the answers are connected by hyperlinks to make it easy for you to navigate from the question to the answer and back again.

Questions

Question 1 .

A method named equals is inherited from the Object class and overridden in several classes in the GM2D03 game-math library.

True or False?

Answer 1

Question 2

The overridden equals method in the GM2D03.Point class returns a value of type double .

True or False?

Answer 2

Question 3

It is not difficult to compare double and float values for absolute equality.

True or False?

Answer 3

Question 4

The overridden equals method of the GM2D03.Point class compares two objects of type GM2D03.ColMatrix for equality.

True or False?

Answer 4

Question 5

The difference between two points is a displacement vector.

True or False?

Answer 5

Question 6

The getDisplacementVector method of the GM2D03.Point class computes the sums of the x and y components of the points that are stored in two column matrix objects.

True or False?

Answer 6

Question 7

The getDisplacementVector method of the GM2D03.Point class returns a value of type GM2D03.ColMatrix .

True or False?

Answer 7

Question 8

The displacement vector that is returned by the getDisplacementVector method of the GM2D03.Point class points from the Point object on which the method is called to the Point object passed as a parameter to the method.

True or False?

Answer 8

Question 9

Kjell describes the component parts of the a displacement vector

• as the distance you would have to walk,
• first along the x-axis and
• then along the y-axis
• to get from the first point to the second point.

True or False?

Answer 9

Question 10

The add method of the GM2D03.ColMatrix class adds one ColMatrix object to another ColMatrix object, returning a ColMatrix object.

True or False?

Answer 10

Question 11

The order in which you add column matrix objects has a significant impact on the result.

True or False?

Answer 11

Question 12

The order in which two column matrix objects are subtracted doesn't matter. The result is the same either way.

True or False?

Answer 12

What is the meaning of the following two images?

This image was inserted here simply to insert some space between the questions and the answers to keep them from being visible on the screen at thesame time.

This image was also inserted for the purpose of inserting space between the questions and the answers.

Answers

Answer 12

False. As you should have learned from your studies of the Kjell tutorial, the order in which the two column matrix objectsare subtracted has a significant impact on the result.

Back to Question 12

Answer 11

False. As you should have learned from your studies of the Kjell tutorial, the order in which the two column matrix objects are addeddoesn't matter. The result is the same either way.

Back to Question 11

Answer 10

True

Back to Question 10

Answer 9

True

Back to Question 9

Answer 8

True

Back to Question 8

Answer 7

False. The getDisplacementVector method of the GM2D03.Point class returns a value of type GM2D03.Vector .

Back to Question 7

Answer 6

False. The getDisplacementVector method of the GM2D03.Point class computes the differences (subtraction) of the x and y components of the points that are stored in two column matrix objects.

Back to Question 6

Answer 5

True

Back to Question 5

Answer 4

True. In effect, this method actually compares two objects of the ColMatrix class by calling the equals method defined in the GM2D03.ColMatrix class. This is because the values that define a point are actually stored in a columnmatrix.

Back to Question 4

Answer 3

False. There is an inherent problem when comparing two double or float values for equality. If you perform a series of computations twice, using adifferent computational order for each set of computations, you are likely to end up with two values that are not absolutely equal even if they shouldbe equal. Arithmetic inaccuracies along the way may cause the two results to differever so slightly. However, they may be equal from a practical viewpoint.

Back to Question 3

Answer 2

False. The overridden equals method in the GM2D03.Point class returns a value of type boolean .

Back to Question 2

Answer 1

True

Back to Question 1

Miscellaneous

This section contains a variety of miscellaneous information.

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