Exam 2

Instructions are the same as previous exam. I suggest you review HW 5-8, reading quizzes 8-16, and activities 14 - 27. Topics include:

• strings (concatenation, repetition, index, length, slice, membership, justification, upper/lower-case, find, replace, ord, chr, str, formatting) and immutability
• encryption and decryption using transposition or substitution cipher
• prompting for user input with input function
• lists (initialization, indexing, concatenation, reptition, membership, length, slicing, append, insert, pop, sort, reverse, index, count, remove, list comprehension) and mutability
• dictionaries (keys, values, items, get, membership, index operator, del)
• tuples (e.g., what is returned from dictionary items)
• read from / write to files
• read from URLs, 4 components of URL (protocol, host, resource, parameters), definition of HTML,
• while loops, definition of infinite loop,
• statistics: definition of dispertion, central tendency, mean, median, mode, frequency distribution, histogram, min and max functions, Pearson correlation coefficient (the range and significance of value)

Exam 1

Overview

• definition of computer science and applications
• Python interpreter, Python prompt, shell vs. file editor
• comments
• primitive types: integers, floating point numbers, strings, booleans
• naming objects, assignment statements, variables, expressions, keywords
• mathematical operators: +, -, *, /, //, %, **
• relational operators: <, <=, >, >=, ==, !=
• logical operators: and, or, not
• using modules and functions provided by Python
  • print
  • turtle module: how to import, create turtle, use functions on turtle forward, goto, right/left, position, dot, penup, pendown
  • math module: how to import, use functions sqrt, use constant pi.
  • random module: how to import, use function random
• constructor, dereferencing and dot operator
• functions (function signature, function definition, parameters, how to call/invoke a function, return)
• for loops, 3 ways to call range, loop variable, accumulator pattern
• if statements (if, elif, else), nested if statements
• approximating pi (Archimedes, Leibniz, Wallis, Monte Carlo)

I suggest you review chapters 1 & 2 from our book, HW 1-4, and reading quizzes 1-7. Our book and all in-class activities give you many examples that you can work through to practice. You can also rewatch lecture videos for additional examples and explanations.

Instructions for Exam

• Once you start the exam, a timer will begin for 60 minutes and your work will automatically be submitted when the timer ends. That timer continues regardless of whether you have the tab open.
• The exam will be posted on Moodle. Do not take the exam in Teams. Use a web browser and open Moodle from there.
• You can start the exam any time beginning Monday 9/21 at 8am, but it is due by 11:59pm Monday 9/21. We will not meet for class that day so that you have time to take the exam.
• I will be available on Teams during our normal class time in the event of questions. I will not be available outside of our regular class time.
• I suggest you do the following BEFORE you start:
  • plug in your laptop charger so you don’t lose battery
  • check that your internet is working
  • ensure you have 60 minutes of uninterrupted time
• Your score will be taken out of 50 points.
• It is open book and open notes, but you will not have time to consult your book/notes for all questions, so please study accordingly.
• It must be completed individually.
• Question format: all questions are worth 1-3 points depending on their level of difficulty and number of subproblems. Questions have the following form.
  • Multiple choice / true false. For example,
    • Given a few lines of code which manipulate a variable, what is the value of a variable after all lines are executed?
    • What is a result of the expression ((True or False) and False)?
    • What is the python prompt?
  • Matching. For example,
    • Pick the appropriate definition/description corresponding to the terms function, selection statement, accumulator variable, and for loop.
  • Rearrange lines of code correctly. For example,
    • Given several lines of code that are out of order, put them in the correct order so that the given function computes the sum of the first N numbers.
  • Fill-in. For example,
    • What is the value of a variable after all lines are executed?
    • Given the following lines of code which approximates Pi, what condition should be inside the if statement?
  • Short responses. For example,
    • Write a function that uses a for loop to compute and returns the sum of the first 10 even numbers (2+4+….+18+20).
    • Describe what a given function does.
    • Describe the difference between == and =
    • Write a function that returns true if a number is even.