CSC 151.01, Class 47: Association Lists

Overview

• Preliminaries
  • Notes and news
  • Upcoming work
  • Extra credit
  • Questions
• Lab
• Debrief

News / Etc.

• Keep your partners (Friday, too).
• I should get proposal reviews out by late tonight.
• I encourage you to sign up for CSC 161!
• I apologize for being so far behind on grading.
• Our preliminaries seem to be getting longer and longer.

Upcoming Work

• Lab writeup: TBD.
• NO Reading for Friday.
• Quiz Friday.
  • Files
  • Algorithm analysis
  • A bit more on HOP
• Projects due next Tuesday.
• Exam 4 distirbuted next Wednesday.

Extra credit (Academic/Artistic)

• CS Extras Thursday, 4:15pm: Project Gadfly
• CS Table Tuesday, noon: Randomness
• CS Extras, Thursday, May 4, 4:15 p.m.: Inclusion in CS. Please attend.
• The Harold W. ’38 and Jean Ryan ’38 Squire Lectureship in Physics. May 2nd, 7:00 p.m., ARH 302. Astrophysicist Kartik Sheth (Grinnell class of 1993) will present From Mumbai to Grinnell to NASA HQ - Adventures in Time and Space

Extra credit (Peer)

• AAA hosts Kit Yan performing Queer Heartache, Wednesday, Harris, 7pm.
• LiNK Fundraiser: They are selling kimbab from 1-4pm ($2 vegan, $3 meat or seafood, $4 everything) to support North Korean refugees in China resettle in South Korea and the US.
• Symphony, Singers, and Oratorio: Sunday at 2pm in Herrick Chapel.
  Brahms Requiem.
• Dance Ensemble show, Staying with the Trouble. Tickets are available in Bucksbaum box office for Thu, Fri, Sat at 7:30 and Sunday at 2:00.
• Drill Team Show, May 5, at Triple V stables. The other side of the golf course. Free rides (cars, not pony) to the event from outside JRC! Plus led pony rides and pet the miniponies.
• Next home baseball game: May 7 (Senior Day)

Extra credit (Misc)

• Make Your Mark on Phase 1!, Tuesday, May 2, 10 a.m., Near the Commencement Stage. (Light refreshments provided.) Leave a hand-print on the construction wall (which will become a Commencement backdrop!) to celebrate the Class of 2017. You can also make chopsticks from wood harvested at the construction site and get your photo taken at the construction-themed photo booth.
• May 4 town hall on belonging. 11am, May 4, JRC 101
• Visit Drake Library from 3:45-4:45 tomorrow to see cool code community games!

Other good things to do

• Dag Field Day, Saturday, April 29, noon-5pm, in the Club Athletic Field.
  • Near the Softball diamond.
• Raging Cow Atlatl event, Saturday, Club Athletic Field, 9:00 a.m.
• Titular head (? whether or not it’s a good thing to do)
• HvZ (also ? whether or not it’s a good thing to do) http://www.hvzsource.com/grinnell/.
• Women in Computing tonight at 7 p.m.

Questions

Can we use text in our programs?

Yes.

(context-list-fonts)
(context-set-fgcolor! "red")
(context-set-font-name! "Monospace Bold")
(context-set-font-size! 30)
(image-display-text! image
                     "Testing one two three"
                     1000 250
                     ALIGN-CENTER       ; Alternately ALIGN-LEFT, ALIGN-RIGHT
                     ALIGN-CENTER)      ; Alternately ALIGN-TOP, ALIGN-BOTTOM
(context-update-displays!)

Are there more procedures that are not documented?

Yes. You can see some by opening the Procedure Browser in GIMP. (Help menu.)

Wow. Those look like a PITA (pain in the neck). What can we do?

If you ask nicely, I can try to adapt them for you.

Lab

For lookup-attributes, should we return if the color is not in the list?

Whatever you decide, provided you document it.

Normal choices: empty list, #f

How will you feel if we make multiple identical calls to assoc in

our procedures?

Sad. You should know better by now.

Debrief

Writeup is 4c.

What does assoc do?

How would you implement assoc?

(define assoc
  (lambda (val alist)
    (cond
      ; Base case
      [_______
       #f]
      ;Found!
      [_______
       _______]
      ; Not found
      [else
       _______])))

Writeup

Write up exercise 4c from the lab on association lists.
Send your solution to csc151-01-grader@grinnell.edu.

Title your email CSC 151.01 Writeup for Class 47 (YOUR FULL NAMES).