Mental Calendar Math
Explanation of how to find the day of the week for a given date, and random drills to practice doing it in your head.
Minkowski Difference of Convex Polygons
Demo of the Minkowski Difference between two convex polygons showing the CSO (configuration space obstacle) and how it changes as the polygons rotate.
Demo of the angles needed to reflect light from a point source to an eye point.
An x/|x| style adjustable sigmoid, and a cubic (the usual cubic? Hermite?) easing function.
Farm Door Pictures
Art references for an online discussion: pictures of doors around the farm, and a few other things constructed out of rough lumber.
Ellie is five months old...
Seed Search Forms
I collected these a couple of years ago for our personal use. This morning I sent the HTML file to the hightunnels list. Then I realized I should put it online so I don't have to keep sending it out when I make updates...
On the Perils of Being a Farmer and a Math Nut
Playing with Proto-J
After another evening of playing with it, I figured out a bunch more stuff, so here's a version with more description of the language, as well as some corrections to the commentary on the implementation.
The Proto Interpreter for J
A very terse (44 lines of C) little interpreter which was apparently part of the inspiration for the implementation of J. I worked through it and wrote up commentary for my personal edification.
I noticed the other day that Stephan Becher's homepage seems to have disappeared, so I'm posting a copy of Strongforth.f. For convenience, I have also extracted the HTML documentation from the archive and am making it directly available.
We found an interesting yellow caterpillar this morning, so I took a few pictures.
Forth to HTML
Here's a quick program to mark up Forth source code with HTML tags.
Building Low Tunnels with Quick Hoops
Quick Hoops info
I'm breaking my quick-hoops stuff up into several pages, linked from here. I updated the hoop-bender plans so they should actually show up correctly in everything (except IE, grr) and print reasonably well.
First Lettuce Sprouting
The lettuce we planted a week ago is starting to come up.
First Seeding Outside
We cleared the spinach and weeds out of one set of quick hoops and planted the first field lettuce of the year.