CIS225 Exam 3

What is unit testing? A. Testing the entire program as one unit. B. Testing separate parts/units of the program separately C. Testing your program by running it repeatedly. D. A way to test the ability of programmers.

Testing separate parts/units of the program separately

Which line would not be found in a truth table for and? a) T T T b) T F T c) F T F d) F F F

T F T

The Boolean operator or returns True when both of its operands are true.

True

The condition x <= y <= z is allowed in Python.

True

The main function is at the top of a functional structure chart.

True

The math.sqrt function cannot compute the square root of a negative number.

True

Top-down design is also called stepwise refinement.

True

Unit-testing is the process of trying out a component of a larger program in isolation.

True

a and (b or c) == (a and b) or (a and c)

True

When a program is being run directly (not imported), the value of __name__ is a) script b) main c) __main__ d) True

__main__

A statement that controls the execution of other statements is called a a) boss structure b) super structure c) control structure d) branch

control structure

What are the advantages of spiral development? A. It makes it easier to tackle a large problem when you don't know ahead of time all the features your program must implement. B. It allows you to add new features and test them even if they weren't part of the initial requirements of the program. C. It allows you to simplify the original problem that may be too complicated to understand initially. D. all of the above E. none of the above

all of the above

Which of the following can be treated as a Boolean expression? a) an int expression b) a float expression c) the result of a comparison operator (such as < or >) d) all of the above

all of the above

Which of the following statements could be true about the following Python code? from random import randrange for i in range(10): print(randrange(10)) A. It might output the numbers 0 through 9 in that older. B. It might output 0 through 9 in some order. C. It might output 0 ten times D. all of the above E. none of the above

all of the above

A Python convention for defining methods that are "private" to a class is to begin the method name with a. "private" b. a pound sign ( # ) c. an underscore ( _ ) d. a hyphen ( - )

an underscore (_)

The best structure for implementing a multi-way decision in Python is a) if b) if-else c) if-elif-else d) try

if-elif-else

A loop pattern that asks the user whether to continue on each iteration is called a(n) a) interactive loop b) end-of-file loop c) sentinel loop d) infinite loop

interactive loop

A multiple choice question is most similar to a) simple decision b) two-way decision c) multi-way decisions d) an exception handler

multi-way decisions

Which of the following is not a valid rule of Boolean algebra? a) (True or x) == True b) (False and x) == False c) not(a and b) == not(a) and not(b) d) (True or False) == True

not(a and b) == not(a) and not(b)

Within a method definition, the instance variable x could be accessed via which expression? a. x b. self.x c. self[ x ] d. self.getX()

self.x

A loop pattern that continues until a special value is input is called a(n) a) interactive loop b) end-of-file loop c) sentinel loop d) infinite loop

sentinel loop

A priming read is part of the pattern for a(n) a) interactive loop b) end-of-file loop c) sentinel loop d) infinite loop

sentinel loop

A graphical view of the dependencies among components of a design is called a A) flow chart B) prototype C) interface D) structure chart

structure chart

A method definition with four formal parameters is generally called with how many actual parameters? a. three b. four c. five d. it depends

three

What is the purpose of an if statement? a) to execute code repeatedly b) to choose whether or not to execute certain code c) to assign a bool value d) all of the above

to choose whether or not to execute certain code

What is the purpose of exception handling? a) to handle errors gracefully so the program does not crash b) to make a program crash c) to make algorithms more efficient d) none of the above

to handle errors gracefully so the program does not crash

A structure in which one decision leads to another set of decisions, which leads to another set of decisions, etc., is called a decision a) network b) web c) tree d) trap

tree

Which of the following statements is true about the Python expression x == 3 or 4? A. it is an invalid statement and the Python interpreter will indicate it is a syntax error. B. It will be true if x is 3 or if x is 4, and false for any other values. C. It will always be false D. It will always be true

It will always be true

Which of the following statements is true about computer simulations? A. They model the real world exactly. B. Once the simulation is written, the input values can be tweaked to see how it affects the results. C. All computer simulations are easy to write. D. All of the above E. none of the above

Once the simulation is written, the input values can be tweaked to see how it affects the results.

A Python string literal can span multiple lines if enclosed with a. " b. ' c. " " " d. \

" " "

What would be the value of total for the following program? total = 0 for i in range(10): for j in range(10): total = total + 1 A. 1 B. 10 C. 20 D. 100

10

Method names should always begin with one or two underscores.

False

Multi-way decisions must be handled by nesting multiple if-else statements.

False

Reading design books alone will make you a great designer.

False

The counted loop pattern uses a indefinite loop.

False

The easiest way to iterate through the lines of a file in Python is to use a while loop.

False

The first parameter of a Python method definition is called this.

False

The python random function returns a pseudo random int.

False

There is usually only one correct solution to a problem involving decision structures.

False

not(a or b) == (not a) or not(b)

False

How is a percent sign indicated in a string formatting template? A) % B) /% C) %% D) /%%

%

Which of the following statements are true? a) An if statement must have an else statement b) An if statement must have an elif statement c) An if statement must have both an elif and an else statement d) An else statement must have a matching if statement

An else statement must have a matching if statement

An expression that evaluates to either true or false is called a) operational b) Boolean c) simple d) compound

Boolean

Which of the following is 'not' a step in pure top-down design? A. Repeat the process on smaller problems B. Detail the algorithm in terms of its interfaces with smaller problems C. Construct a simplified prototype of the system D. Express the algorithm in terms of smaller problems.

Construct a simplified prototype of the system

A Docstring is the same thing as a comment.

False

A developer should use either top-down design or spiral design, but not both.

False

A sentinel loop asks the user whether to continue on each iteration.

False

A simplified version of a program is called a simulation.

False

A two-way decision is implemented using an if-elif statement.

False

An object may have only one instance variable.

False

Computers can generate truly random numbers.

False

Functions that live in objects are called instance variables.

False

In Python conditions, ≠ is written as /=.

False

In data processing, a collection of information about a person or thing is called a file.

False

Which line would not be found in a truth table for or? a) T T T b) T F T c) F T F d) F F F

F T F

Input validation means prompting a user when input is required.

False

A simulation that uses probabilistic events is called A) Monte Carlo B) pseudo random C) Monty Python D) chaotic

Monte Carlo

Which of the following statements is true? a) There is usually only one algorithm to solve a problem b) There is often more than one way to solve a problem and some ways may be more efficient than others c) There is often more than one way to solve a problem but they are all equally efficient d) All of the Above e) None of the Above

There is often more than one way to solve a problem and some ways may be more efficient than others

A Python 'while' implements a indefinite loop.

True

A sentinel loop should not actually process the sentinel value.

True

A simple decision can be implemented with an if statement.

True

A single try statement can catch multiple kinds of errors.

True

A top-down design is best implemented from the top down.

True

A while is a pre-test loop.

True

In a Python class, the constructor is called __init__.

True

In top-down design, the main algorithm is written in terms of functions that don't yet exist.

True

Instance variables go away once a method terminates.

True

It is considered bad style to directly access an instance variable outside of a class definition.

True

New objects are created by invoking a constructor.

True

Strings are compared by lexicographic ordering.

True

In a Button widget, what is the data type of the instance variable active? a) bool b) int c) float d) str

bool

In the racquetball simulation, what data type is returned by the gameOver function? A) bool B) int C) string D) float

bool

What statement can be executed in the body of a loop to cause it to terminate? a) if b) input c) break d) exit

c) break

What Python reserved word starts a class definition? a. def b. class c. object d. __init

class

The term applied to hiding details inside class definitions is a. obscuring b. subclassing c. documentation d. encapsulation

encapsulation

A method definition is similar to a(n) a. loop b. module c. import statement d. function definition

function definition

In top-down design, the subcomponents of the design are A) objects B) loops C) functions D) programs

functions

Which of the following Python statements is invalid? a) if x!=4: b) if x = 4: c) if x ==4: d) if 2 < x < 4:

if x = 4:

In Python, the body of a decision is indicated by a) indentation b) parentheses c) curly braces d) a colon

indentation

A loop that never terminates is called a) busy b) indefinite c) tight d) infinite

infinite

The arrows in a module hierarchy chart depict A) information flow B) control flow C) sticky-note attachments D) one-way streets

information flow

A while loop written as while True A. will always be an infinite loop no matter what the loop body contains B. might be an infinite loop no matter what the loop body contains C. might be an infinite loop depending on what the loop body contains D. will never execute the loop body

might be an infinite loop depending on what the loop body contains

Placing a decision inside of another decision is an example of a) cloning b) spooning c) nesting d) procrastination

nesting

A loop structure that tests the loop condition after executing the loop body is called a a) pre-test loop b) loop and a half c) sentinel loop d) post-test loop

post-test loop

Taking the square root of a negative value with math.sqrt produces a(n) a) ValueError b) imaginary number c) program crash d) stomach ache

program crash

The initial version of a system used in spiral development is called a A) starter kit B) prototype C) mock-up D) beta-version

prototype

Which expression is true approx 66% of the time? A) random () >=66 B) random() <0.66 C) random()<66 D) random()>=0.66

random()>=0.66

Which of the following methods is not part of the Button class in this chapter? a) activate b) deactivate c) setLabel d) clicked

setLabel

Which of the following methods is part of the DieView class in this chapter? a) activate b) setColor c) setValue d) clicked

setValue

The term for an operator that may not evaluate one of its sub-expressions is a) short-circuit b) faulty c) exclusive d) indefinite

short-circuit

The term for an operator that may not evaluate one of its subexpressions is A. short-circuit B. faulty C. exclusive D. indefinite

short-circuit

The easiest place in a system structure to start unit-testing is A) the top B) the bottom C) the middle D) the main function

the bottom