CSC151.02 2015S, Class 03: An Introduction to Scheme ==================================================== * Keep the same partners from the last class. * Fruit! * No handouts in the back of the room. _Overview_ * Preliminaries. * Admin. * Upcoming Work. * Extra Credit. * Questions on algorithms. * Questions on Scheme readings * Quiz * Lab. Preliminaries ------------- ### Admin * Lots of preliminaries today! * Evening tutor sessions start Sunday night. * A purple sheet is going around the room to get interest in mentor session times. * We keep hot water going 24/7 in the CS Commons for students in CS classes. * The index cards in the back of the room are to support your note-taking systems. * I would recommend using the white cards for vocabulary. * I would recommend using one color for grammar (syntactic structures). * I would recomment using one color for algorithmic concepts. * You can think about how to use other colors. * *Please be responsible in your consumption of the cards.* * In case you didn't know, you can submit questions anonymously via the "Submit Questions" link. * No attendance today; the quizzes serve for attendance. * I keep eboards for the review sessions, too. You can find links to them in the obvious places. * I told you on Wednesday that I keep changing the number of key things that can go into algorithms. I realize that I left out one in our discussions: You need to rely on *basic operations* that the person or device carrying out the algorithm already knows. * Since it's weekend, a few reminders. * Consider in advance what you want and what you feel comfortable with. * If you choose to partake, please partake responsibly. * Remember that consent is difficult to give or receive if you have been partaking. ### Upcoming Work * Lab writeup for lab 3, Problem 2. Due Monday (preferably before class, but as late as 10:30 p.m. is okay) * [Assignment 2](../assignments/assignment.02.html) distributed. * Due Tuesday at 10:30 p.m. * I have assigned partners for the assignment. * I will give you five minutes at the end of class to find those partners. * Readings for Monday: * [Symbolic Values](../readings/symbols-reading.html) * [Numeric Values](../readings/numbers-reading.html) ### Extra Credit Opportunities #### Academic #### Peer Support (Afternoon Section) * Men's Baskeball, Saturday, 3 p.m., NewDarby * Meditation group, Saturday, 4 p.m., CRSSJ * Meditation group, Wednesday, 9:00 p.m., CRSSJ * Swimming, Friday, January 30, 6:30 p.m., Osgood Natatorium * Swimming, Saturday, January 31, noon, Osgood Natatorium * Men's Tennis, Saturday, January 31, Field House ### Recommended Events (no EC unless mentioned above) * Women's Baskeball, Saturday, 1 p.m., NewDarby * Belly Dance Club, to be scheduled * Salsa Club, Tuesdays at 7pm and Sundays at 2pm * #OneGrinnell, Wednesday, February 4 at 4:15 p.m. * Economics talks, Spanish talks ### Questions on Algorithms _How do we write an algorithm without formal experience?_ > You are sentient > You can use English > It's something I asked you to think about _How can I write an algorithm to add two numbers?_ > Teach someone to increment and decrement, and use repeated "increment first, decrement second" > Draw a line of length a inches, a subsequent line of length b inches, and measure the result. > Teach them to look it up in a table. > Teach them to use a calculator. ### Questions on Scheme _In what order does Scheme evaluate things?_ > Inside out > If you have multiple expressions, evaluates them first to last. > If a procedure is arithmetical and takes more than two parameters, we often think about doing it left to right. _Do all the definitions have to be in the definitions pane and all the non-definitions in the interactions pane?_ > Custom, not requirement. Quiz! ----- * When you finish the quiz, start the lab. Lab --- * I'll interrupt you with about five minutes to go so that you can find your homework partners.