Chapter 7

Question 1

algorithm

Answer 1

A step-by-step process for solving a category of problems.

Question 2

body

Answer 2

The statements inside a loop.

Question 3

breakpoint

Answer 3

A place in your program code where program execution will pause (or break), allowing you to inspect the state of the program’s variables, or single-step through individual statements, executing them one at a time.

Question 4

bump

Answer 4

Programmer slang. Synonym for increment.

Question 5

continue statement

Answer 5

A statement that causes the remainder of the current iteration of a loop to be skipped. The flow of execution goes back to the top of the loop, evaluates the condition, and if this is true the next iteration of the loop will begin.

Question 6

counter

Answer 6

A variable used to count something, usually initialized to zero and incremented in the body of a loop.

Question 7

cursor

Answer 7

An invisible marker that keeps track of where the next character will be printed.

Question 8

decrement

Answer 8

Decrease by 1.

Question 9

definite iteration

Answer 9

A loop where we have an upper bound on the number of times the body will be executed. Definite iteration is usually best coded as a for loop.

Question 10

development plan

Answer 10

A process for developing a program. In this chapter, we demonstrated a style of development based on developing code to do simple, specific things and then encapsulating and generalizing.

Question 11

encapsulate

Answer 11

To divide a large complex program into components (like functions) and isolate the components from each other (by using local variables, for example).

Question 12

escape sequence

Answer 12

An escape character, \, followed by one or more printable characters used to designate a nonprintable character.

Question 13

generalize

Answer 13

To replace something unnecessarily specific (like a constant value) with something appropriately general (like a variable or parameter). Generalization makes code more versatile, more likely to be reused, and sometimes even easier to write.

Question 14

increment

Answer 14

Both as a noun and as a verb, increment means to increase by 1.

Question 15

infinite loop

Answer 15

A loop in which the terminating condition is never satisfied.

Question 16

indefinite iteration

Answer 16

A loop where we just need to keep going until some condition is met. A while statement is used for this case.

Question 17

initialization

Answer 17

To initialize a variable is to give it an initial value. Since in Python variables don’t exist until they are assigned values, they are initialized when they are created. In other programming languages this is not the case, and variables can be created without being initialized, in which case they have either default or garbage values.

Question 18

iteration

Answer 18

Repeated execution of a set of programming statements.

Question 19

loop

Answer 19

The construct that allows allows us to repeatedly execute a statement or a group of statements until a terminating condition is satisfied.

Question 20

loop variable

Answer 20

A variable used as part of the terminating condition of a loop.

Question 21

meta-notation

Answer 21

Extra symbols or notation that helps describe other notation. Here we introduced square brackets, ellipses, italics, and bold as meta-notation to help describe optional, repeatable, substitutable and fixed parts of the Python syntax.

Question 22

middle-test loop

Answer 22

A loop that executes some of the body, then tests for the exit condition, and then may execute some more of the body. We don’t have a special Python construct for this case, but can use while and break together.

Question 23

nested loop

Answer 23

A loop inside the body of another loop.

Question 24

newline

Answer 24

A special character that causes the cursor to move to the beginning of the next line.

Question 25

post-test loop

Answer 25

A loop that executes the body, then tests for the exit condition. We don’t have a special Python construct for this, but can use while and break together.

Question 26

pre-test loop

Answer 26

A loop that tests before deciding whether the execute its body. for and while are both pre-test loops.

Question 27

single-step

Answer 27

A mode of interpreter execution where you are able to execute your program one step at a time, and inspect the consequences of that step. Useful for debugging and building your internal mental model of what is going on.

Question 28

tab

Answer 28

A special character that causes the cursor to move to the next tab stop on the current line.

Question 29

trichotomy

Answer 29

Given any real numbers a and b, exactly one of the following relations holds: a < b, a > b, or a == b. Thus when you can establish that two of the relations are false, you can assume the remaining one is true.

Question 30

trace

Answer 30

To follow the flow of execution of a program by hand, recording the change of state of the variables and any output produced.