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Gray code at the pediatrician's office (plover.com)
47 points by zkz on June 21, 2009 | hide | past | favorite | 11 comments



Maybe I'm being a bit slow today ... but I don't see the binary numbers encoded in the pattern.

I get gray codes (yay Karnaugh maps from EE101!), but I just don't see the binary numbers - someone mind explaining?


sure thing - read the strips in horizontal rows of 10 bits from the top down, giving a white pixel a value of 0 and a black pixel a 1. So, on the gray code strip on the right, we see:

    0000000000
    0000000001
    0000000011
    0000000010
    0000000110
    0000000101
...etc. Does that make sense?


Upvoted for the mentioning of Karnaugh maps! For a subject I'm not particularly interested in (binary arithmetic and logic), I found Karnaugh maps and some of the stuff we did with them in Phy220 quite brilliant and interesting.


Just curious, what code speak is this: EE101, Phy220?

My guess is Electrical Engineering course number id 101 and Physics course number id 220.

Did you guys attend the same college or is there a larger part of the world where these ids are standardized?


Actually the course number for me was 'ECE 110.'

A 101 course is, traditionally, the first course in a series while 'EE' is traditionally 'Electrical Engineering.' Hence, 'EE101' is an idiomatic way (at least in America) to indicate the first Electrical Engineering course a student would take in college.


Thanks a lot. Solves my occasional wondering about the exact semantics behind some uses of CS101.


The rule of thumb is that '100'-level courses are for first year undergrads, '200'-level for second years, '300' level for 3rd years, '400' for fourth years, and '500'-level for graduate courses.

There are, obviously, a lot of exceptions. Many people will take 200/300 level courses their first year if they are comfortable with the subject. And a handful of schools use entirely different systems - my current school uses '000'-level to denote 'introductory' courses, '100'-level for 'advanced' undergrad, and '200'-level to signify a graduate course.


Thanks again. Would you care to enlighten me on another puzzling educational expression: one-term course.

For example you may see in the teachers guide of a textbook: This can be covered in a one-term course.

How much 'study volume' i.e. study hours total does such a one-term course comprise?


One term is a semester, which is ~ 4months. Most classes meet about 4 hours a week, so ~60 hours of class time per term. Profs always say you should spend 2 hours studying out of class for every hour in class, but very few people do that - I probably average about 1 hour out of class per 3 hours in class (but some classes take far more time).

So, figure a bare minimum of 60 hours, an average of about 80 hours, and an upper bound of about 200 hours (very rare, but there are a few classes that have problem sets from hell).


I see. Several culture and subculture dependent interpretation issues here too.

No further questions. You may rest :)


They're not standardized, it's just course numbers like you said.




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