EBoard 02: Getting started with our lab equipment (Section 2)
Warning! You are being recorded (and transcribed) (provided the technology
is working correctly).
Today’s start-of-class procedure
- Take one of the business cards.
- Identify where the named computer is.
- Drop the business card in the jar.
- Navigate to that computer.
- Today only: Start the lab.
- When a second person arrives, introduce yourself.
Note: If you need to sit in a particular area of the classroom, let me know
and we’ll work things out in the future.
Approximate overview
- Lots of administrative stuff, no attendance [10 min]
- Questions [5 min]
- Debrief on last class [10 min]
- The pre-activity activity [5 min]
- The activity [5 min]
- Lab one: Get yourself setup for MathLAN. (Both partners.) [15 min]
- Lab two: Play with DrRacket [30 min]
- Layers! [10 min]
Administrative stuff
Introductory notes
- Something that didn’t end up in the syllabus and should have: I’m
not only bad at remembering names, I’m likely to swap them. (There’s
a longer statement that’s now in the syllabus.) I apologize.
- I should also report that I believe that all teaching is performative.
- I make it a practice to call on students using a set of cards with
names on it.
- I use this process to give you practice “thinking on your feet”,
as it were.
- I also use this process to help everyone realize that they are
not the only one who is puzzled.
- And I use the process to push you a bit.
- Feel free to say “I’m not sure” or “I’d prefer not to answer.”
- If you don’t want to be called on in class, please let me know.
- The
csc151 library (which you’ll learn about in lab today) is
updated regularly. Each time you sit down to work, you should try to
update the version you have. The lab will tell you how.
- Also: Let me know when you encounter bugs or unexpected behavior.
- You should only submit the reading checks with double-daggers (‡).
- Readings are taking people longer than I’d expected. If they continue
to take many people more than an hour, I’ll find ways to cut back.
- Consider setting up password reset on https://passwordreset.grinnell.edu.
Upcoming activities
Scholarly
- Tuesday, 2025-01-28, 4:00–5:00 p.m., TBD.
CS Candidate Talk: Intelligent Tutoring Systems and Equity in Math
Education.
- Thursday, 2025-01-30, 11:00 a.m.–noon, JRC 101.
Scholars’ Convocation: The Once and Future Grinnell College.
Artistic
Multicultural
- Saturday, 2025-02-01, 1:00–10:00 p.m., Harris Concert Hall.
Lunar New Year Celebration.
Peer
Musical, theatric, sporting, and academic events involving this section’s
students are welcome.
Wellness
- Tuesday, 2025-01-28, 12:15–12:50 p.m., GCMoA.
Yoga in the Museum.
- Tuesday, 2025-01-28, 4:30–6:30 p.m., BRAC P103 (Multipurpose Dance Studio).
Wellness Yoga.
- Tuesday, 2025-01-28, 7:30–9:00 p.m., Harris Concert Hall (aka Harris Gym).
Queer Stompede
Misc
- Thursday, 2025-01-30, 4:00–5:00 p.m., Noyce 3821.
CS Major Declaration Info Session.
- Tea beforehand in the CS Commons.
Other good things
These do not earn tokens, but are worth your consideration.
- Saturday, 2025-02-01, 10:00 a.m.–1:00 p.m., Field House.
Grinnell Track and Field Invitational.
Upcoming work
- Due Friday, 2024-01-24
- Due Sunday, 2024-01-26
Friday PSA
- If you choose to take advantage of body/brain-altering substances, please
do so in moderation.
- Remember that everyone has different limits. (Both physical and conceptual.)
Choose what is appropriate for you and try to stick to it.
- Consent is absolutely essential (but not sufficient).
Q&A
I have answered questions for all the reading responses that came in by
8:00 p.m. If you have another question and want it answered now, please
ask.
Administrative
How do I record tokens?
On the “Tokens earned” assignment on Gradescope.
Does Racket have any real-world or industry applications, or is it mainly just designed as a teaching tool?
A variant of Racket was used to both the first version of Yahoo Stores. There are a few niche software development studios that use Racket. But DrRacket is mostly for teaching. Walmart uses Clojure (a more robust Scheme-like language) for sales and inventory management.
MathLAN
How do I run Linux on my computer?
You shouldn’t need to run Linux on your computer.
You can run DrRacket on your computer. (Instructions are in the
syllabus).
You can also log into MathLAN remotely, but it’s a bit complicated.
https://mathlan.sites.grinnell.edu/fastx/2022/06/08/MathLAN-Remote-Access/.
Racket/Scheme
What is a trivial expression?
One that does not involve any operations. Sample trivial expressions
include numbers and strings.
What are values?
The numbers and other things we use in our computations.
What is a basic value?
A value that does not itself contain other values. That may sound werid,
but Scheme has things like lists, which contain, well, lists of values.
In the readings, it mentioned that DrRacket and also Scamper had modifications and features designed for beginners. what are these features specifically?
Scamper provides a feature that lets you “trace” how a Scheme expression is evaluated.
DrRacket tries to provide novice-friendly feedback about errors.
Could you clarify what a delimiter is in the string-split procedure?
(string-split "a,b,c|d,e,f" ",")
The delimiter is the character (or sequence of characters) we use to
identify where to split strings. We might split on commas or spaces
or ….
What are last set of number inputs when using procedures like outlined-circle?
For an outlined circle, the last set of numbers give the thickness of the
outline.
What details are important to keep in mind and not ignore when working with scheme? like order and rules?
Use parentheses to indicate “this is an expression to be evaluated”.
Put the operation immediately after the open parentheses.
Keep track of what kinds parameters (inputs) each procedure has. Do they
expect numbers, strings (words surrounded by quotation marks), images,
…?
Debriefing
The pre-instruction activity
How could we have made the group-forming process more efficient?
(Think, Pair, Share)
- Assign people to the people next to them.
- Assign different numbers to locations in the room.
- The chaos was relatively efficient. Shouting out your number and holding
up the card worked well.
The sandwich activity
What might you have learned from the sandwich activity? (TPS)
- Be very specific with your instructions.
- The computer may not understand things in the same way that you do.
Computers (or Sams) think differently than we do.
- Know what the state of your system is. Don’t bother writing instructions
that the computer already knows.
Lab one
- Make sure that both partners attempt the first lab.
- The 2024Sp should be 2025Sp. Sorry!
Lab two
- Get this from the class Web site.
- Jump ahead to 7 a,b,c
- Then 9
- Then submit
- Then go back and do what you’ve missed.
Layers!