Python Midterm Exam

operator used to perform string concatenation in Python

+

if the variable num contains a positive integer, what are the only two possible results of the expression num % 2

0 and 1; two either divides the number evenly or there is one left over

if the current value of the variable num1 is 2 and the current value of num2 is 3, what value will be stored in num2 after the following line of code is executed num2 /= num1 * num2

0.5; 2*3 = 6 3/6 = 0.5

Which value of num will cause the print statement in the following code to be executed? if num < 15: if num + 7 >= 20: print('There you go!')

13

If a variable called address refers to the string '123 Main Street', what is the result of the expression address.find('3')

2

what output is produced by the following code: print(15 + 30)

45

Which of the following is a relational operator

<=

what output is produced by the following code: print('Jan', 'Feb', 'Mar', sep='-')

Jan-Feb-Mar

What output would be produced when the following code is executed? state = 'Mississippi' print(state.replace('is', 'was'))

Mwasswassippi

output

The data produced by an algorithm

Granualarity

The level at which an instruction is expressed.

if a variable called jedi refers to the string 'Yoda', what is the result of the expression jedi * 3

YodaYodaYoda

Which of the following expressions could be used to determine if a is not less than b

a>=b

print( 'apple', 'banana' )

apple banana print function separates its output by a space by default

what is a docstring

character string used as a comment in a program

if a variable called word refers to the string 'committee', what is the result of the expression word.strip('m')

committee strip only strips these letters if they're at the end or beginning

an if statement cannot have both an elif and an else clause

false

true or false: python 3 is backwards compatible to python 2

false; Python 3 broke backward compatibility, meaning some code that was valid in Python 2 code does not run on Python 3 platforms

true or false: Python variables that represent integers are NOT object reference variables

false; all python variables are object references

pass statement is usless

false; it is very useful

true or false: python was named after a snake

false; named after a monty python comedy group

true or false: the origin point (0, 0) of the turtle coordinate system is in the upper left corner of the graphic screen

false; origin point is in the center of the screen

The arithmetic operators have a lower precedence than the relational operators

false; other way around

A Python function must have at least one parameter

false; some functions have no parameters

The less than operator (<) should not be used to compare floating point values

false; there is no danger in doing this

true or false: the stroke color of a filled turtle shape must be the same as the fill color

false; they can be different

true or false: a turtle draws a filled circle using the fill_circle command

false; this command doesn't exist

true or false: in dynamically typed languages, variables are declared to store a specific type of data

false; variables do not have to be declared in dynamically typed languages

true or false: the effect of the setheading depends on the current heading of the turtle

false; when setting the heading explicitly, the current heading doesn't matter

true or false: running a program that contains errors will cause thonny to terminate

false; your program will terminate but thonny will not

of the options given, what values of the variables height, size, and width would cause the following code to set the variable weight to 100? if height < size: weight = 50 if width < 20: print('short') else: if width > 100: weight = 100 println('tall')

height = 15 size = 10 width = 110

thonny is best described as

integrated development environment

if a variable called user_id refers to the string 'AEinstein12', what is the result of the expression user_id.isalpha()

is alpha only works if all the characters in the string are alphabetic

What output is printed by the following code if it is executed when appetizer is 3 and entree is 12? if appetizer > 1: if entree < 7: print('ketchup') else: print('mustard') else: if appetizer < 0: print('mayonnaise') else: print(relish)

mustard

text that requests user input is called

prompt

if a variable called greeting refers to the string 'hello', what does the expression greeting.upper() accomplish

returns a new string containing the characters "HELLO"

syntax coloring

showing certain elements of program code in different colors

Which of the following statements is true?

statements in the body of an if statement must be indented

Which of the following is NOT true regarding the return statement?

the last statement in a function must be the return statement this is often the case, but not a requirement

What will happen if the variable total has the value 5 when the following code is executed? if total > 8: print('collywobbles')

the word collywobbles is not printed and processing continues

A character string can be used as the condition of an if statement

true

A function parameter ceases to exist when the function returns to the caller

true

In Python, the relational operators can be used to put character strings in alphabetical order

true

The relational operators all return boolean results

true

The result of a relational operator can be assigned to a variable

true

a function can return a boolean result

true

pass statement can be used as the body of an if statement, for loop, function definition, or class definition

true

true or false: full documentation of the python standard library can be found online

true

true or false: python is a general purpose programming language, appropriate for solving problems in many areas of computing

true

true or false: setting the turtle's speed to 0 turns off the animation of the turtle movement completely

true

true or false: thonny displays code using syntax highlighting

true

variables declared inside a function cannot be accessed from outside that function

true

The pass statement has no effect on the program state

true, doesn't compute anything

Which way would the turtle be facing after executing the command turtle.setheading(135)

up and left (northwest)

the turtle circle command can be used to draw a regular polygon

true; the optional parameter steps

true or false: you can store a value in a variable in the python shell

true; the state of variables is maintained from one command to the next

true or false: built in functions of the python standard library can be used without being imported

true; they are essentially part of the python language

principles embraced by python programming language

1. beautiful is better than ugly 2. simple is better than complex 3. explicit is better than implicit 4. complex is better than complicated 5. readability counts

Python embodies elements of which programming paradigm

1. procedural programming 2. object-oriented programming 3. functional programming

what is the result of the expression math.floor(12.843)

12 returns nearest integer less than x

result of expression max(6, 17)

17

if a variable called pioneer refers to the string 'Grace Murray Hopper', what is the result of the expression len(pioneer)

19 len refers to characters in a string

Which of the following is NOT a valid Python identifier first_place place1 1stplace FIRST_PLACE

1stplace an identifier cannot begin with a digit

what is the result of the expression math.pow(3, 3)

27; 3^3

15 % 6

3; because 6 goes into 15 two times with 3 left over

what is the result of the expression 7 // 2

3; the fractional part is truncated

what is the result of the expression 43 % 5

3; there is 3 leftover after the division is performed

if the current value of size is 2, what value will be stored in size after the following line of code is executed size *= 3

6 2*3=6

if the current value of the variable num is 4, what value will be stored in num after the following line of code is executed num += 2

6 4+2=6

What value is assigned to the variable num by the following statement if the current value of num is 4 num = num * 2

8

if the current value of the variable count is 2, what value will be stored in count after the following line of code is executed count += count * 3

8 2*3 =6 + 2 = 8

flowchart

A graphical representation of the logic of an algorithm

pseudocode

A language that is independent of any particular programming language

Algorithm

A step-by-step procedure for solving a problem

who developed python programming language?

Guido van Rossum

what output is produced by the following code: print('Ready', end=' ') print('Set', end='') print('Go')

Ready SetGo the end argument is a space in the first call but empty in second call

a print statement is

a call to a function

what is the python standard library

a collection of programming components that can be used in any python program

what issue must be addressed when printing a long character string

a regular string literal cannot span across multiple lines

what is the python shell

a window in which python statements and expressions are executed immediately

if a variable called business refers to the string 'Time Warner', what is the result of the expression business[6]

a; string indexes start at 0

which of the following does the input function NOT do when it is called

convert the user input to an integer but it does: return the value typed by the user wait for the user to type information and press enter print a message if provided

input

data needed by an algorithm to accomplish its task

what line of code is equivalent to the following depth += 50 * offset

depth = depth + (50 * offset)

Which way would the turtle be facing after executing the following code turtle.setheading(270) turtle.right(20) turtle.left(65)

down and right (southeast)

true or false: using components from the python standard library is a rare occurrence

false; any useful python program will rely on the standard library

true or false: the assignment statement is also an expression

false; assignment operator does not return a value

A Python block comment begins with a double slash (//)

false; begins with a #

The input function will produce an error if the value read is not numeric

false; int and float produce an error

A Python comment cannot appear on a line that contains an executable statement

false; it can be put after a line of code to explain that code

true or false: the goto command moves the turtle without drawing a line, even if the turtle's pen is down

false; it will draw a line if the turtle's pen is lowered

true or false: if both operands to the remainder operator (%) are positive, a divisor of n will produce a result in the range 1 to n

false; it will produce a result in the range 0 to n-1

true or false: a python program must be compiled into an executable form before it can be run

false; python programs are interpreted, executing the code line by line

true or false: a python program must be enclosed in curly brackets {} to be executed

false; python statements do not have to be enclosed by anything. A single statement is a complete program

true or false: You must use a print statement to display the result of an expression in the Python shell

false; the expression is evaluated and the result is displayed immediately

true or false: the expression x ^ y raises the value x to the power y

false; the python exponentiation operator is **

true or false: all mathematical functions in Python are part of the math module

false; there are several math functions that are built in

true or false: value assigned to a variable must be numeric

false; value can be one of several non-numeric types, such as character strings

suppose the integer variable hours contains a value that represents a number of hours. which of the following expressions will compute how many 24-hour periods are represented by that value, without worrying about any leftover hour

hours // 24 integer division throws the amount leftover away

natural language

language that humans use to communicate, such as French or English

the assignment operator has a _______ precedence than all the arithmetic operators

lower

what output is produced by the following code: print('oak', 'elm', 'pine', end='!', sep='#')

oak#elm#pine!

if a variable called son refers to the string 'Justin', what is the result of the expression son[-3]

t

what does case sensitive mean

the difference between uppercase and lowercase letters matters

print('Total: ' + 100 + 20)

this line would produce an error; you can't concatenate a string and integer in python

Which of the following identifiers follows the convention for naming Python variables: totalValue Total_Value total_value TOTAL_VALUE

total_value should use undercase letters and have an underscore to separate words

The input, int, and float functions are all built-in functions

true

a comment in a Python program is ignored by the interpreter

true

python comments begin with a hash mark (#) and extend to the end of the line

true

the input function always returns the read data as a character string

true

true or false: the math.pi constant represents pi to 15 decimal places

true

true or false: the pencolor and size determines the color and width of lines drawn

true

true or false: the position of the turtle depends on the current heading of the turtle

true

true or false: the python shell has an integrated help system

true

true or false: the python turtle graphics module is based on the programming language Logo developed in the 1960s

true

true or false: thonny has a package manager that lets you install and update external python packages

true

true or false: python variables are created using an assignment statement

true; a variable is created the first time it is assigned to a value

true or false: the math module contains a constant that represents the value pi to several digits

true; also has a constant for e

true or false: if either or both operands to the division operator (//) are floating point values, then the result will be a floating point value

true; and if both are integers, it performs integer division

true or false: the value assigned to a variable could be a floating point number

true; both integers and floating point numbers can be stored in variables floating point number ex: 4.2

true or false: if a filled shape drawn by a turtle is not fully enclosed, Python fills the shape as if the starting point is connected to the end point.

true; but the stroke will not be shown for the connecting line

true or false: the python shell is great for exploring python langauge features

true; it's a quick way to try a newly learned statement, operator or function

you cannot change the contents of Python character string once it has been created.

true; python strings are immutable

true or false: the value of a variable can change throughout the program

true; that's why it's called a variable, its value can vary

true or false: output of a program run in thonny appears in the shell window

true; the command to run the program along with any text output produced by the program will appear in the shell window

if the turtle is currently facing up (north), which way would it be facing after executing the command turtle.right(45)

up and right (northeast)