Here you can find the course news, reproduced from the individual
Monday, October 7, 2002:
Notes on Exam 1
- I noticed a few small errors in
- The last line of
(word-value (car (car histogram))))))
and should instead read
(word-value (car (car histogram)) word-values))))
- The line in
extract-words-helper that read
(cons (car chars) word-chars)
should instead read
(cons (char-downcase (car chars)) word-chars)
- Someone asked what I like to see for tests within the code. I like
- (1) A display of a note that explains the test.
- (2) A display of the Scheme code you're about to run for the test.
- (3) The test.
- (4) A comment showing the result
- For example,
(display "Testing foo on the empty list.\n")
(display "(foo null)\n")
- Are there any other questions on exam 1?
- Does anyone read the class news?
- Yes, Friday's class was fun. But let's strive for fewer classes that
are fun in that peculiar way.
- I'm taking Daniel (youngest) to the doctor for shots this afternoon,
and won't be available in my office. I will check email this evening.
Friday, October 4, 2002:
- I've graded homework 4.
- I've emailed each of you some notes on your assignment.
- You should read my notes on
homework 4 before you turn in the exam.
- We'll look at some issues with
- We may also look at some other procedures.
- I do not plan to grade homework 3.
- I don't think you'd like me to grade it.
- When time permits, I will release some notes on it.
- Are there questions on exam 1?
- No, you don't need to use
assoc in your implementation
- The Putnam Mathematics Exam (a full day of challenging mathematical
problems) is on Saturday, 7 December, from 9am to 5pm.
- Email email@example.com
to sign up.
- You're guaranteed to do at least as well as I did when I took it
twenty years ago.
Wednesday, October 2, 2002:
- My bad week continues. I managed to leave my car windows open last
night. Bad plan Sam.
- I have not yet graded homework 3.
I will probably grade homework 4
first, since it is more relevant to the exam.
Tuesday, October 1, 2002:
Monday, September 30, 2002:
- One of you asked me a pair of questions on Friday:
true that you're the hardest grader in CS? and
If so, does that mean that doing well in your class suggests
I'll do well in my other CS classes?
- No, I don't think I'm the hardest grader.
- I do tend to assign some harder problems, though, particularly
at the introductory level.
- Not all students who do well in my classes do as well in the
- Are there any questions on my
notes on homework 2?
- No, I haven't graded homework 3.
- Are there any questions on homework
- No, the other CS151 and this class aren't covering topics in the
- Yes, we cover the same core topics.
- But we also look at some different topics.
- I haven't done much
rabble rousing this semester, so ...
- The faculty are making motions about the long-range planning
committee today. Has student government made any comments on
student or staff representation on that committee? It should.
- I know a number of people are concerned about the destruction
of Darby. I'll claim that (1) Nothing is inevitible until
it's done and (2) There are certainly tactics available for
saving Darby (primarily ones that involve raising money or
threatening to withhold money).
Friday, September 27, 2002:
- I've graded homework 2.
- You should have received your grade in the mail.
- I'd recommend that you read
the notes on homework 2.
- With your permission, I'm going to reuse parts of your answers
in a sample writeup for next year's class.
- We may have prospies today.
- Microsoft has just released
vision of the future. I particularly like the idea of voice
mail over email. As one colleague suggested,
Several contributors to the Slashdot commentary on this story are
looking forward to the arrival of spam in the Cubicle of the Future,
complete with Active X controls that crank up the volume before rendering
those invitations to [spam topic of your choice].
Wednesday, September 25, 2002:
- Many of you sent me notes at 3 a.m. indicating that you weren't able
to get the homework done because of unknown errors.
- I will not penalize you for the lateness on this assignment.
- This offer is only available to those who show up for class.
- I'll wander around during lab to see if I can fix your problems.
- For the future: I'd rather that you go to sleep before midnight than that
you get my assignments in on time.
- And as today shows, those who need to work beyond midnight don't often
finish their assignments anyway.
- To continue our "P" theme, I brought pudding and pastries as well as
Pop-Tarts (and today I brought real Pop Tarts as opposed to other kinds
of toaster pastries).
- The focus of today's class is
the recursion lab.
- No, I do not yet have homework 2 graded.
- If you haven't done so already, please read
Recursion with Natural Numbers.
Tuesday, September 24, 2002:
- Are there any final questions on
- Any food choices other than pop-tarts for tomorrow?
- I'm still trying to find time to grade
- Yes, I plan to have today's lab take two days.
Monday, September 23, 2002:
- I'm running low on toaster pastries. I probably won't be able to replace them
until Wednesday, so don't plan on food tomorrow.
- In any case, tomorrow's class is later in the morning, so you should
have less need (or so I hope).
- Today's class will replicate the strategy we used on Friday: Lots of
group discussion with some
Now play with it on the computer
- There will probably be a formal lab on this material tomorrow.
- No extra reading, but you should have read
Repetition with Recursion.
- I've been asked to remind you that the Preservation Hall Jazz Band
plays at 8pm tomorrow night in Herrick.
Friday, September 20, 2002:
- Welcome to any visiting parents.
- The problem with Web pages appearing in an Courier was due to an
error in my sample HTML. Where we use
<lang="eng">, we should be using
- Are there any questions on homework 3?
- Warning: Last Friday's class was Friday the 13th. This Friday's class
is Class #13.
Wednesday, September 17, 2002:
- Kathleen Skerrett is giving the convocation talk tomorrow. She is one
of the better speakers I've heard on campus and I recommend that you attend.
- There's a math talk today at 4:15 on "Graph Theory and Golf Balls".
It sounds like a lot of fun.
- I won't be available from 2:15-3:05 today since I'm visiting one of
Dr. Gum's classes.
- I have no idea why our pages all appear in Courier. I'm still working
on the problem.
- No reading for Friday. Work on the two CGI labs.
Tuesday, September 17, 2002:
- As you've requested, I've put
last Friday's examples online.
- Any remaining questions on homework 2?
- If you need to reach me ...
- I'll be available after class
- I'll be in my office from about 1:30 to 2:15 today and in the MathLAN
from about 2:15 to 3:05.
- I'll check my email tonight (probably some time between 8 and 10 pm)
- The More CGI reading is not
yet available. Check after 5pm. If it's still not available, assume
that I'm not going to write it.
Monday, September 16, 2002:
- We're running low on pop-tarts. Are there any other breakfast foods
- I made a mistake on the due date for
homework 2. As is the case with
most homework, homework 2 is due on Wednesday.
- Are there any questions on that homework?
- I forgot to assign readings on Friday, so we may spend a little more
time in lecture today than I'd planned.
- I also don't have all the reference pages created for today's lab.
- I'd recommend that you wait until this afternoon to read the CGI
Friday, September 13, 2002:
- Don't forget to save your daily work in a file.
- Warning! Friday the 13th falls on a Friday this month.
Wednesday, September 11, 2002:
- Coffee and Poptarts.
- On Friday, we're going to have our first
pause for breath
of the semester. We'll review what we've done to date and look
at some of the key problems in more depth.
- On Friday, I'll also assign the first lab writeup and discuss the
procedures for writing and turning in lab reports. It is likely
that I will ask you to write up some problems from the
procedures lab and
some problems from the conditionals
- Almost everyone turned in HW1 long before class.
- The times some of you sent your homework were depressing.
- "Site" and "Cite" are different words.
Tuesday, September 10, 2002:
- Are there any questions on homework 1?
- Reese will have office hours tonight (and every Tuesday)
from about 9:00 to 10:00 p.m.
- I'll be holding a lab in MathLAN from 2:15-3:05 today. Feel free to
stop by and ask me questions.
- I might also be available after 3:05. If you want to talk to me,
please let me know.
- I finally picked up a coffee pot, so we'll have coffee in class starting
today. Please be careful with the coffee!
Monday, September 9, 2002:
- I wasn't able to get a coffee pot over the weekend. I'll try tonight
- Are there any questions on homework 1?
- A few of you were confused about the construction of
(a (b c) (d (e)))
- You should build all lists from back to front.
's a step-by-step construction
> (define elist (cons 'e null))
> (define elistlist (cons elist null))
> (define de (cons 'd elistlist))
> (define delist (cons de null))
> (define bc (cons 'b (cons 'c null)))
> (define bcde (cons bc delist))
((b c) (d (e)))
> (define abcde (cons 'a bcde))
(a (b c) (d (e)))
- Here's it all put together
(cons (cons 'b (cons 'c null))
(cons (cons 'd (cons (cons 'e null) null))
Friday, September 6, 2002:
Wednesday, September 4, 2002:
- I finally got to reading your introductory surveys. Thanks
for spending so much time on them. Here are some answers to questions
- Tell me about your educational background. I have a
bachelor's degree in Math from the University of Chicago and
both a Master's and a Ph.D. in Computer Science from Chicago.
Before coming to Grinnell, I was a visiting professor at Dartmouth.
Oh, I went to Newton North High School in Newton, Massachusetts (as
did Pablo Silva).
- What do you consider a good student? One who tries hard
and participates actively in class.
- Can women succeed in CS? Although I agree that men and
women sometimes approach problems differently, my experience has
been that women can do as well or better than men in CS. The best
student I taught was a woman. I also think that CS needs more women,
in part because men and women do approach problems differently, and
the field benefits from different approaches.
- How old are your kids? William is 7 and in 2nd grade.
Jonathan is 4 and starting preschool. Daniel is 1 and starting to
figure out some words.
- What kinds of research do you do? Most of my research
these days involves the Web and hypermedia. One project involves
adding more interactivity to the Web (e.g., annotations) by
mediating the conversation between browser and server.
My students and I build tools that transform pages on the fly.
Another project involves building tools that let us analyze the ways
in which students use course webs to see if there are patterns that
successful students tend to use (and which we could therefore teach
to less successful students). Mostly, I look for projects that I think
(1) can have a real impact, (2) are at a level that Grinnell students
can contribute successfully, and (3) seem to be fun and interesting.
- We'll spend a few minutes talking about
- I'd like to make sure that each of you has a group.
- I've intentionally left the assignment relatively open.
- I'm in the process of updating the
reading on lists. I'd prefer if you
wait until after 3pm today or so to do that reading.
Tuesday, September 3, 2002:
- Returning to the
Why don't more people use Scheme? question:
It may be a return to the old VHS vs. Beta (or Windows vs. Mac or Unix)
question: People don't always use what's best, and don't always understand
what criteria they should use.
Monday, September 2, 2002:
- Some of you had problems submitting your surveys. I'm sorry about
that problem. (I made one small change and didn't check to ensure
that things still worked afterwards.)
- No, I haven't had a chance to read through them yet.
Friday, August 30, 2002:
Since this page changes so frequently, no history is available.