About the Biorhythm Charting Service
The origins of the program that creates these biorhythm charts dates
back to the early days of minicomputers, circa 1973, when Brian
Johnson ("Uncle BJ") created a Fortran program that "plotted" a
biorhythm chart on fan-fold paper using a line printer attached to a
Data General Nova
computer running
RDOS.
In 1976, I converted Uncle BJ's program to the
C programming language
running under
UNIX version 6
as an exercise in learning how to better code in C
with UNIX-style file I/O, this time creating output on a
ASR33 Teletype.
Then in 1998, more than two decades later, I again used it as a
learning exercise, this time implementing it as a
CGI program
that produces
Portable Network Graphics
(PNG) images for the world wide web.
Unfortunately I lost track of Uncle BJ around 1990, not long he after let me drive his
Harley Davidson around Berkeley. BJ's whereabouts today are unknown, but if anyone
reading this knows more, please send me email. As for me, you can read more about what I do
on my web site.
Tom Ferrin
February 6, 1998