#+title: jst

#+date: <2015-04-02>

jst = juggling skill tree

If you have ever played a computer role playing game, you may have
noticed the protagonist sometimes has a skill "tree" (most of the time
it is actually a directed acyclic graph), where certain skills leads to
others. For example,
[[http://hydra-media.cursecdn.com/diablo.gamepedia.com/3/37/Sorceress_Skill_Trees_%28Diablo_II%29.png?version=b74b3d4097ef7ad4e26ebee0dcf33d01][here]]
is the skill tree of sorceress in
[[https://en.wikipedia.org/wiki/Diablo_II][Diablo II]].

Now suppose our hero embarks on a quest for learning all the possible
juggling patterns. Everyone would agree she should start with cascade,
the simplest nontrivial 3-ball pattern, but what afterwards? A few other
accessible patterns for beginners are juggler's tennis, two in one and
even reverse cascade, but what to learn after that? The encyclopeadic
[[http://libraryofjuggling.com/][Library of Juggling]] serves as a good
guide, as it records more than 160 patterns, some of which very
aesthetically appealing. On this website almost all the patterns have a
"prerequisite" section, indicating what one should learn beforehand. I
have therefore written a script using [[http://python.org][Python]],
[[http://www.crummy.com/software/BeautifulSoup/][BeautifulSoup]] and
[[http://pygraphviz.github.io/][pygraphviz]] to generate a jst (graded
by difficulties, which is the leftmost column) from the Library of
Juggling (click the image for the full size):