Python Coding

get a hint

hint

What Python statement would you like me to run?

What Python statement would you like me to run?

(Chapter 1) When Python is running in the interactive mode and displaying the chevron prompt (>>>) - what question is Python asking you?

20

(Chapter 1) What will the following program print out:

>>> x = 15

>>> x = x + 5

>>> print x

.py

(Chapter 1) Python scripts (files) have names that end with:

for

(Chapter 1) Which of these words is a reserved word in Python ?

quit()

(Chapter 1) What is the proper way to say "good-bye" to Python?

Central Processing Unit

(Chapter 1) Which of the parts of a computer actually execute the program instructions?

A sequence of instructions in a programming language

(Chapter 1) What is "code" in the context of this course?

Secondary Memory

(Chapter 1) A USB memory stick is an example of which of the following components of computer architecture?

The computer did not understand the statement that you entered

(Chapter 1) What is the best way to think about a "Syntax Error" while programming?

Random steps

(Chapter 1) Which of the following is not one of the programming patterns covered in Chapter 1?

# This is a test

(Chapter 2) Which of the following is a comment in Python?

123abc

(Chapter 2) What does the following code print out?

hours

(Chapter 2) Which of the following variables is the "most mnemonic"?

stop

(Chapter 2) Which of the following variables is the "most mnemonic"?

Retrieve the current value for x, add two to it and put the sum back into x

(Chapter 2) What does the following statement do? x = x + 2

Parenthesis ()

(Chapter 2) Which of the following elements of a mathematical expression in Python is evaluated first?

2

(Chapter 2) What is the value of the following expression? 42 % 10

5

(Chapter 2) What is the value in x after the following statement executes: x = 1 + 2 * 3 - 8 / 4

98

(Chapter 2) What value be in the variable x when the following statement is executed?

x = int(98.6)

Pause the program and read data from the user

(Chapter 2) What does the Python raw_input() function do?

Indent the line below the if statement

(Chapter 3)

What do we do to a Python statement that is immediately after an if statement to indicate that the statement is to be executed only when the if statement is true?

=

(Chapter 3) Which of these operators is not a comparison / logical operator?

Depending on the value of x, either all three of the print statements will execute or none of the statements will execute

(Chapter 3)What is true about the following code segment:

if x == 5 :

print 'Is 5'

print 'Is Still 5'

print 'Third 5'

You de-indent the next line past the if block to the same level of indent as the original if statement

(Chapter 3) When you have multiple lines in an if block, how do you indicate the end of the if block?

You have most likely mixed tabs and spaces in the file

(Chapter 3)

You look at the following text:

if x == 6 :

print 'Is 6'

print 'Is Still 6'

print 'Third 6'

It looks perfect but Python is giving you an 'Indentation Error' on the second print statement. What is the most likely reason?

except

(Chapter 3) What is the Python reserved word that we use in two-way if tests to indicate the block of code that is to be executed if the logical test is false?

Small

All done

(Chapter 3) What will the following code print out?

x = 0

if x < 2 :

print 'Small'

elif x < 10 :

print 'Medium'

else :

print 'LARGE'

print 'All done'

This code will never print 'Something else' regardless of the value for 'x'

(Chapter 3)

For the following code,

if x < 2 :

print 'Below 2'

elif x >= 2 :

print 'Two or more'

else :

print 'Something else'

What value of 'x' will cause 'Something else' to print out?

1

(Chapter 3) 'In the following code (numbers added) - which will be the last line to execute successfully?

(1) astr = 'Hello Bob'

(2) istr = int(astr)

(3) print 'First', istr

(4) astr = '123'

(5) istr = int(astr)

(6) print 'Second', istr

-1

(Chapter 3) For the following code:

astr = 'Hello Bob'

istr = 0

try:

istr = int(astr)

except: istr = -1

What will the value for istr after this code executes?

A built-in function

(Chapter 4) In Python what is the raw_input() feature best described as?

def

(Chapter 4) Which Python keyword indicates the start of a function definition?

10

20

(Chapter 4) What will the following Python code print out?

def func(x) :

print x

func(10)

func(20)

Bonjour Michael

(Chapter 4) What will the following Python

program print out?

def greet(lang):

if lang == 'es':

return 'Hola'

elif lang == 'fr':

return 'Bonjour'

else:

return 'Hello'

print greet('fr'),'Michael'

Avoiding writing the same non-trivial code more than once in your program

(Chapter 4) What is the most important benefit of writing your own functions?

x

(Chapter 4) In the following Python code, which of the following is an "argument" to a function?

x = 'banana'

y = max(x)

print y

print x

There

(Chapter 4)

What does the following code print out?

def thing():

print 'Hello'

print 'There'

You de-indent a line of code to the same indent level as the def keyword

(Chapter 4) In Python, how do you indicate the end of the block of code that makes up the function?

print 'World'

(Chapter 4)

Which line of the following Python program is useless?

def stuff():

print 'Hello'

return

print 'World'

stuff()

2

(Chapter 4)What does the following Python code print out? (Note that this is a bit of a trick question and the code has what many would consider to be a flaw/bug - so read carefully).

def addtwo(a, b):

added = a + b

return a

x = addtwo(2, 7)

print x

Hellothere

(Chapter 6)

What does the following Python Program print out?

str1 = "Hello"

str2 = 'there'

bob = str1 + str2

print bob

42

(Chapter 6) What does the following Python program print out?

x = '40'

y = int(x) + 2

print y

printx[8]

(Chapter 6)

How would you use the index operator [] to print out the letter q from the following string?

x = 'From [e-mail]'

print x[14:17]

(Chapter 6) How would you use string slicing [:] to print out 'uct' from the following string?

x = 'From [e-mail]'

letter

(Chapter 6)

What is the iteration variable in the following Python code?

for letter in 'banana' :

print letter

42

(Chapter 6)

What does the following Python code print out?

print len('banana')*7

print greet.upper()

(Chapter 6) How would you print out the following variable in all upper case in Python?

greet = 'Hello Bob'

twist()

(Chapter 6) Which of the following is not a valid string method in Python?

.ma

(Chapter 6)

What will the following Python code print out?

data = 'From [e-mail] Sat Jan 5 09:14:16 2008'

pos = data.find('.')

print data[pos:pos+3]

strip()

(Chapter 6) Which of the following string methods removes whitespace from both the beginning and end of a string?

Collection variables can store multiple values in a single variable

(Chapter 8) How are "collection" variables different from normal variables?

print len(data)

(Chapter 8) Which of the following Python statements would print out the length of a list stored in the variable data?

A list of integers

(Chapter 8) What type of data is produced when you call the range() function?

x = range(5)

append()

(Chapter 8) What list method adds a new item to the end of an existing list?

for / in

(Chapter 8) What are the Python keywords used to construct a loop to iterate through a list?

print friends[2]

(Chapter 8) For the following list, how would you print out 'Sally'?

friends = [ 'Joseph', 'Glenn', 'Sally' ]

6

(Chapter 8) What does the following Python code print out?

a = [1, 2, 3]

b = [4, 5, 6]

c = a + b

print len(c)

Glenn

(Chapter 8)

What will the following Python code print out?

friends = [ 'Joseph', 'Glenn', 'Sally' ]

friends.sort()

print friends[0]

t[2:4]

(Chapter 8) Which of the following slicing operations will produce the list [12, 3]?

t = [9, 41, 12, 3, 74, 15]

Nothing would print - the program fails with a traceback

(Chapter 8) What would the following Python code print out?

fruit = 'Banana'

fruit[0] = 'b'

print fruit

Zap

ABC

Zap

(Midterm) What will the following Python program print out:

# define functions

def fred():

print "Zap"

def jane():

print "ABC"

# Main program

Zap = 42

ABC = 22

fred()

jane()

fred()

To make your program run faster

(Midterm) Which of the following is not a reason to use a function in your program

Jane returns!

Jane returns!

(Midterm) What will the following Python program print out:

def fred():

return "Fred returns!"

def jane():

return "Jane returns!"

print jane()

fred()

print jane()

h

e

l

l

o

(Midterm)

What will the following Python code print out?

i = 10

list1 = ['h','e','l','l','o']

for i in list1:

print i

The Main memory

(Midterm)

Where in the computer is a variable such as "x" stored?

x = 123

The program would show an error and a traceback on the second line

(Midterm) What would happen if the following Python code were executed?

st = "abc"

ix = int(st)

Parenthesis

(Midterm) If all of the following were used in a Python expression, which would have the highest precedence (i.e. which would be evaluated first)?

11 Hello

(Midterm) What will the following Python program print out? (This is a bit tricky so look carefully).

def hello():

print "Hello"

print "There"

x = 10

x = x + 1

print x, "Hello"

(5/9)

(Midterm) You develop the following program in Python:

f = int(raw_input("Enter:"))

c = ( f - 32 ) * ( 5 / 9 )

print "Celsius",c

And when you run it three times you get the following output:

Enter:212

Celsius 0

Enter:72

Celsius 0

Enter:15

Celsius 0

What part of the program is causing the output to always be zero?

12

(Midterm) For the following Python program, what will it print out?

x = 0

for value in [3, 41, 12, 9, 74, 10] :

if value < 10 :

x = x + value

print x

count = 1

(Midterm)

This Python program is supposed to compute the average of a list of numbers but the output is always wrong. Which line is in error?

total = 0

count = 0

for abc in [3, 41, 12, 9, 74, 15] :

total = total + abc

count = 1

ave = total / count

print ave

-1

(Midterm) For the following Python program, what will it print out?

x = -1

for value in [3, 41, 12, 9, 74, 15] :

if value < x :

x = value

print x

Bonjour

(Midterm)

What is the output of the following program, if the user input is: fr?

# define function 'greet'

def greet(lang):

if lang == 'es': # if lang is Spanish

print 'Hola'

return 'adios'

elif lang == 'fr': # French

print 'Bonjour'

return 'au revoir'

else:

print 'Hello'

return 'bye'

xx = raw_input('enter language: ')

#----main program begins here---

yy= greet(xx)

hello

yo

Done!

(Midterm) What is the output of the following Python code, given the following inputs?

hello

# hi

yo

done

# Python code begins here

while True:

line = raw_input('>')

if line[0] == '#' :

continue

if line == 'done':

break

print line

print 'Done!'

The program will run indefinitely

(Midterm) What will happen if this code is run?

n = 5

while True:

print n

n = n - 1

print 'Done!'

5

4

3

Done!

(Midterm) What is the output of this code?

n = 5

while True:

if n < 3: break

print n

n = n - 1

print 'Done!'

5 3 1 Done

(Midterm)

What will this code output? (note the comma after a print statement)

n = 5

while n > 0:

print n,

n = n - 2

print 'Done!'

6

5

4

3

Done!

(Midterm) What is the output of this code?

n = 6

while True:

print n

if n == 3: break

n = n - 1

print 'Done!'

6

5

2

1

Done!

(Midterm) What is the output of this code? (note the 'continue')

n = 6

while n > 0:

if n in [3,4]: # this is a list, where n is checked for either 3 or 4

n = n-1

continue

print n

n = n - 1

print 'Done!'

2

(Midterm) What does the following Python code print out? (Note that this is a bit of a trick question and the code has what many would consider to be a flaw/bug - so read carefully).

def addtwo(a, b):

added = a + b

return a

x = addtwo(2, 7)

print x

This loop will run forever

(Chapter 5) What is wrong with this Python loop:

n = 5

while n > 0 :

print n

print 'All done'

Exits the currently executing loop

(Chapter 5) What does the break statement do?

Jumps to the "top" of the loop and starts the next iteration

(Chapter 5) What does the continue statement do?

5

(Chapter 5)

What does the following Python program print out?

tot = 0

for i in [5, 4, 3, 2, 1] :

tot = tot + 1

print tot

friend

(Chapter 5) What is the iteration variable in the following Python code:

friends = ['Joseph', 'Glenn', 'Sally']

for friend in friends :

print 'Happy New Year:', friend

print 'Done!'

Sum all the elements of a list

(Chapter 5)

What is a good description of the following bit of Python code?

zork = 0

for thing in [9, 41, 12, 3, 74, 15] :

zork = zork + thing

print 'After', zork

-1

(Chapter 5) What will the following code print out?

smallest_so_far = -1

for the_num in [9, 41, 12, 3, 74, 15] :

if the_num < smallest_so_far :

smallest_so_far = the_num

print smallest_so_far

Hint: This is a trick question and most would say this code has a bug - so read carefully

matches both type and value

(Chapter 5) What is a good statement to describe the is operator as used in the following if statement:

if smallest is None :

smallest = value

while

(Chapter 5) Which reserved word indicates the start of an "indefinite" loop in Python?

0

(Chapter 5) How many times will the body of the following loop be executed?

n = 0

while n > 0 :

print 'Lather'

print 'Rinse'

print 'Dry off!'

Python lists maintain order and dictionaries do not maintain order

(Chapter 9) How are Python dictionaries different from Python lists?

Traceback error

(Chapter 9) What would the following Python code print out?

stuff = dict()

print stuff['candy']

Associative arrays

(Chapter 9) What is a term commonly used to describe the Python dictionary feature in other programming languages?

What is a common use of Python dictionaries in a program?

(Chapter 9) Building a histogram counting the occurrences of various strings in a file

counts[key] = counts.get(key,0) + 1

(Chapter 9) Which of the following lines of Python is equivalent to the following sequence of statements assuming that counts is a dictionary?

if key in counts:

counts[key] = counts[key] + 1

else:

counts[key] = 1

It loops through the keys in the dictionary

(Chapter 9)

In the following Python, what does the for loop iterate through?

x = dict()

...

for y in x :

...

values()

(Chapter 9) Which method in a dictionary object gives you a list of the values in the dictionary?

To provide a default value if the key is not found

(Chapter 9) What is the purpose of the second parameter of the get() method for Python dictionaries?

-1

(Chapter 9) What would the following Python code print out?

stuff = dict()

print stuff.get('candy',-1)

False

(Chapter 9) TRUE or FALSE: When you add items to a dictionary they remain in the order in which you added them.