It looks as if someone who grew up coding in FORTRAN on punched cards just ran their brain through f2c then wrote that code. It's very old-school FORTRAN-like.
Hmm I guess I was being to obtuse from the downvotes. Having not found the code from the article I was very interested in checking it out when the link was posted here. Sadly the code is written in such as way that makes it extremely difficult to easily learn anything from. Reading the code is often the best way to understand how a program/problem runs. I went to the source to answer the following questions: How is the snowflake generated? What factors need to be taken into account? Looking at the code if you want to figure anything you would have to put a lot of time and effort into it. Badly named variables and function names are just one of the problems. Take for example 'initialize()', what does it initialize? Is it only initializing snow flake code, only X11 code, both or just a dumping ground function? What about the check() function? What does it check? and chi()? There is a shape12, but not a shape6 or shape3 function, why not? What does parupdate do? What about norminf()? None of this answers the original questions. How do I simulate growing a snowflake?
If the code was written in a sane way you would be able to skim through it in two minutes and have a good overview of how a snowflake is made. Given that it would probably take a good hour at least to understand it and I am only so-so interested in learning I wont bother. This is especially sad given that this is coming out of edu where I would presume that part of the purpose is to teach how a snowflake is grown.
That's true for ordinary programs, but this is math, not software. Glancing at the code in this case is kind of like glancing through some program's object code or disassembly and trying to understand how it works: theoretically possible in principle, but not really doable in practice. In math the proper analogue to "glancing at the code" is "skimming the paper", which is here: http://psoup.math.wisc.edu/papers/h2l.pdf
If this was generated from some math formulas or from some other code (such as a fortran translator as another comment hinted), but if this was the code that was created by the author I stand by my original statement.
