Don Marti

Mon 17 Apr 2006 10:33:39 PM PDT

Keybindings and aumix

I bound a couple of unused keys to "aumix" to tweak the volume on the computer. Levels go from 0 to 100, so in order to run from min to max in 25 steps, I used steps of +4 and -4, like this:

aumix -v +4

aumix -v -4

But that didn't let me get every possible level, and in real life I turned out to want to be able to tweak the volume to within one unit. So here's a better choice: up is "aumix -v +3" and down is "aumix -v -5". I can hit every possible value with a little up-and-down fiddling, and still make large changes pretty quickly.

Math puzzle that might make a good exercise for programming students: for any integer n, find a pair of up and down values that minimizes total keypresses for all volume changes from 1 to n.

Here's an example of great user interface, from a Magnavox digital alarm clock I used to own. The "set time fast" button went forward, and the "set time slow" button went backward. So you get to the time you want, overshoot a little, go back, and Bob's your uncle, instead of get to the time you want, overshoot, go around 23.5 hours, then sneak up slowly on the time you want.