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patrickwonders
patrickwonders

Need to clean the keyboard...

The letter b has been going on my laptop for quite some time now. It may just need a good cleaning. I hope that is all.

I had my world all sorted out to deal with this. My complicated passwords no longer required the ASCII-66. My vi techniques have adapted to not being able to count on n's right-hand-man (yes, Brad, I still haven't learned Dvorak).

Alas, it's been six years since I last made an effort to use emacs. I am trying to get back into it because of slime and its noweb mode.

This has really highlighted the need for a functioning b key.


patrickwonders
patrickwonders

Fractal representation of binary operations

A few weeks back, I was playing with fractal representations of binary operations. For the math-phobic, Don't panic yet. General binary operations are pretty simple. Suppose you have a collection of things. A binary operation on those things is just a way of taking two of those things, putting them together (in order), and getting another one of those things.

For example, subtraction is a binary operation on numbers. If you take two numbers (in order) and subtract them, you end up with a number.

For a non-number example, suppose there is a club with four members: Larry, Moe, Curly, and Shemp. Suppose that the last two people to arrive at the monthly meeting must each pay $5 to some member of the club where the recipient is totally laid out in the by-laws based on who the second-to-last and last arrival were. For example, the by-laws might say that if Larry arrives second-to-last and Moe arrives last, they must each pay $5 to Shemp. The by-laws may say that if Shemp arrives second-to-last and Curly arrives last, they each must pay $5 to Curly. (Curly drafted the by-laws and then railroaded them past the other members.) If the by-laws cover all possible cases and only ever pay a single member of the club, then the by-laws define a binary operation on the members of the club.

Okay, now the math-phobic can panic...Collapse ) And, the lisp-phobic, too...Collapse )
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