Python Coding
(Chapter 2) What is the value in x after the following statement executes: x = 1 + 2 * 3 - 8 / 4
5
(Chapter 8) What does the following Python code print out? a = [1, 2, 3] b = [4, 5, 6] c = a + b print len(c)
6
(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!'
6 5 2 1 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 4 3 Done!
(Chapter 9) Which method in a dictionary object gives you a list of the values in the dictionary?
values()
(Chapter 6) What will the following Python code print out? data = 'From [email protected] Sat Jan 5 09:14:16 2008' pos = data.find('.') print data[pos:pos+3]
.ma
(Chapter 1) Python scripts (files) have names that end with:
.py
(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!'
0
(Chapter 3) Which of these operators is not a comparison / logical operator?
=
(Chapter 8) What will the following Python code print out? friends = [ 'Joseph', 'Glenn', 'Sally' ] friends.sort() print friends[0]
Glenn
(Chapter 6) What does the following Python Program print out? str1 = "Hello" str2 = 'there' bob = str1 + str2 print bob
Hellothere
(Midterm) What would happen if the following Python code were executed? st = "abc" ix = int(st)
The program would show an error and a traceback on the second line
(Chapter 4) What does the following code print out? def thing(): print 'Hello' print 'There'
There
(Chapter 6) Which of the following is not a valid string method in Python?
twist()
(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
x
(Chapter 8) What type of data is produced when you call the range() function? x = range(5)
A list of integers
(Chapter 9) What is a term commonly used to describe the Python dictionary feature in other programming languages?
Associative arrays
(Chapter 4) What is the most important benefit of writing your own functions?
Avoiding writing the same non-trivial code more than once in your program
(Chapter 9) In the following Python, what does the for loop iterate through? x = dict() ... for y in x : ...
It loops through the keys in the dictionary
(Midterm) What will the following Python program print out: def fred(): return "Fred returns!" def jane(): return "Jane returns!" print jane() fred() print jane()
Jane returns! Jane returns!
(Chapter 5) What does the continue statement do?
Jumps to the "top" of the loop and starts the next iteration
(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
matches both type and value
(Chapter 5) Which reserved word indicates the start of an "indefinite" loop in Python?
while
(Chapter 3)What is true about the following code segment: if x == 5 : print 'Is 5' print 'Is Still 5' print 'Third 5'
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 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?
Indent the line below the if statement
(Chapter 4) Which line of the following Python program is useless? def stuff(): print 'Hello' return print 'World' stuff()
print 'World'
(Chapter 8) For the following list, how would you print out 'Sally'? friends = [ 'Joseph', 'Glenn', 'Sally' ]
print friends[2]
(Chapter 6) How would you print out the following variable in all upper case in Python? greet = 'Hello Bob'
print greet.upper()
(Chapter 8) Which of the following Python statements would print out the length of a list stored in the variable data?
print len(data)
(Chapter 6) How would you use string slicing [:] to print out 'uct' from the following string? x = 'From [email protected]'
print x[14:17]
(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
count = 1
(Chapter 1) Which of these words is a reserved word in Python ?
for
(Chapter 8) What are the Python keywords used to construct a loop to iterate through a list?
for / in
(Chapter 2) Which of the following is a comment in Python?
# This is a test
(Chapter 4) What will the following Python code print out? def func(x) : print x func(10) func(20)
10 20
(Chapter 4) In Python what is the raw_input() feature best described as?
A built-in function
(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?
This code will never print 'Something else' regardless of the value for 'x'
(Chapter 5) What is wrong with this Python loop: n = 5 while n > 0 : print n print 'All done'
This loop will run forever
(Chapter 8) What list method adds a new item to the end of an existing list?
append()
(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!'
hello yo Done!
(Chapter 2) Which of the following variables is the "most mnemonic"?
hours
(Chapter 6) What is the iteration variable in the following Python code? for letter in 'banana' : print letter
letter
(Chapter 2) What does the following code print out?
123abc
(Chapter 2) What is the value of the following expression? 42 % 10
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
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
2
(Chapter 1) What will the following program print out: >>> x = 15 >>> x = x + 5 >>> print x
20
(Chapter 6) What does the following Python code print out? print len('banana')*7
42
(Chapter 6) What does the following Python program print out? x = '40' y = int(x) + 2 print y
42
(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?
(5/9)
(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?
-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
-1
(Chapter 9) What would the following Python code print out? stuff = dict() print stuff.get('candy',-1)
-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
-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
(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"
11 Hello
(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
12
(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)
Bonjour
(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'
Bonjour Michael
(Chapter 1) Which of the parts of a computer actually execute the program instructions?
Central Processing Unit
(Chapter 8) How are "collection" variables different from normal variables?
Collection variables can store multiple values in a single variable
(Chapter 5) What does the break statement do?
Exits the currently executing loop
(Chapter 9) TRUE or FALSE: When you add items to a dictionary they remain in the order in which you added them.
False
(Chapter 8) What would the following Python code print out? fruit = 'Banana' fruit[0] = 'b' print fruit
Nothing would print - the program fails with a traceback
(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)?
Parenthesis
(Chapter 2) Which of the following elements of a mathematical expression in Python is evaluated first?
Parenthesis ()
(Chapter 2) What does the Python raw_input() function do?
Pause the program and read data from the user
(Chapter 9) How are Python dictionaries different from Python lists?
Python lists maintain order and dictionaries do not maintain order
(Chapter 1) Which of the following is not one of the programming patterns covered in Chapter 1?
Random steps
(Chapter 2) What does the following statement do? x = x + 2
Retrieve the current value for x, add two to it and put the sum back into x
(Chapter 1) A USB memory stick is an example of which of the following components of computer architecture?
Secondary Memory
(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'
Small All done
(Chapter 1) When Python is running in the interactive mode and displaying the chevron prompt (>>>) - what question is Python asking you?
What Python statement would you like me to run?
(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
Sum all the elements of a list
(Midterm) Where in the computer is a variable such as "x" stored? x = 123
The Main memory
(Chapter 1) What is the best way to think about a "Syntax Error" while programming?
The computer did not understand the statement that you entered
(Midterm) What will happen if this code is run? n = 5 while True: print n n = n - 1 print 'Done!'
The program will run indefinitely
(Chapter 9) Building a histogram counting the occurrences of various strings in a file
What is a common use of Python dictionaries in a program?
(Midterm) Which of the following is not a reason to use a function in your program
To make your program run faster
(Chapter 9) What is the purpose of the second parameter of the get() method for Python dictionaries?
To provide a default value if the key is not found
(Chapter 9) What would the following Python code print out? stuff = dict() print stuff['candy']
Traceback error
(Chapter 4) In Python, how do you indicate the end of the block of code that makes up the function?
You de-indent a line of code to the same indent level as the def keyword
(Chapter 3) When you have multiple lines in an if block, how do you indicate the end of the if block?
You de-indent the next line past the if block to the same level of indent as the original if statement
(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?
You have most likely mixed tabs and spaces in the file
(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()
Zap ABC Zap
(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?
except
(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!'
friend
(Midterm) What will the following Python code print out? i = 10 list1 = ['h','e','l','l','o'] for i in list1: print i
h e l l o
(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
5
(Midterm) What is the output of this code? n = 5 while True: if n < 3: break print n n = n - 1 print 'Done!'
5 4 3 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!'
5 3 1 Done
(Chapter 2) What value be in the variable x when the following statement is executed? x = int(98.6)
98
(Chapter 1) What is "code" in the context of this course?
A sequence of instructions in a programming language
(Chapter 6) How would you use the index operator [] to print out the letter q from the following string? x = 'From [email protected]'
printx[8]
(Chapter 1) What is the proper way to say "good-bye" to Python?
quit()
(Chapter 2) Which of the following variables is the "most mnemonic"?
stop
(Chapter 6) Which of the following string methods removes whitespace from both the beginning and end of a string?
strip()
(Chapter 8) Which of the following slicing operations will produce the list [12, 3]? t = [9, 41, 12, 3, 74, 15]
t[2:4]
(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
counts[key] = counts.get(key,0) + 1
(Chapter 4) Which Python keyword indicates the start of a function definition?
def
