CSC151.01 2015S, Class 03: An Introduction to Scheme
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* Keep the same partners from the last class.
* Feel free to take a piece of fruit.
* No handouts!

_Overview_

* Preliminaries.
    * Admin.
    * Upcoming Work.
    * Extra Credit.
    * Questions in preparation for quiz.
    * Questions on Scheme.
    * Quiz!
* Lab.

Preliminaries
-------------

### Admin

* Lots of preliminaries today!
* We (almost) always have a pot of hot water going in the CS commons for
  students taking CS classes.
* When would you like mentor sessions?
* 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.
* The CS tutors start on duty Sunday night 7-10 pm.
* 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: Problem 2.  Due Monday at 10:30 p.m., but preferably
  before class.  <http://bit.ly/151-2015S-lab03>.
* [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 

* Friday, 12:10 p.m. (TODAY), JRC 224A (Day PDR), CS Table, "Computer 
  Programming as an Art" (copies outside my office)

#### Peer Support (Morning Section)

* Swimming, Friday, January 30, 6:30 p.m., Osgood Natatorium
* Swimming, Saturday, January 31, noon, Osgood Natatorium
* Julia's radio show, "The Hot Box".  Wednesday night/Thursday morning 
  1:00-2:00 a.m. 

### Recommended Events (no EC unless mentioned above)

* Belly Dance Club, to be scheduled
* Salsa Club, Tuesdays at 7pm and Sundays at 2pm
* Meditation group, Wednesdays at 9:00 and Sundays at 4:00 in CRSSJ
* #OneGrinnell, Wednesday, February 4 at 4:15 p.m.

### Questions on Algorithms

### Questions on Scheme

_What is `(square 4)`?_

> Possible interpretations: Compute the square of 4, compute the square
  root of 4, draw a square with side-length 4.  `square` means "multiply
  by itself".  Square root is written `sqrt`.  "Draw a square" does not
  have a single command.

### Quiz

* The ideal is ten minutes.
* But if you need a few minutes longer, that's okay.
* Whichever partner finishes first should start getting the lab set.

Lab
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