About the JavaRhythm Applet
JavaRhythm displays an animated biorhythm chart for a period
beginning two weeks before the requested "Biorhythm Date" and ending
two weeks after. Each animated dot is the value of a biorhtyhm curve
on a particular day. Simply type in your birthday and a date of
interest, and JavaRhythm redraws the curves for those days.
You may stop the drawing by clicking in the animation display area.
Note that the drawing threads complete their current drawing cycle
before going to sleep. This allows you to print the graph without
the chaser effect showing up.
This applet is almost over-threaded. Each curve is drawn by a separate
Java thread whose speed is proportional to the frequency of its
corresponding biorhythm cycle. Coordination of the overall animation
and the user interface is handled by other threads.
When a new date is entered, the current set of curves is instructed to
die while the new ones begin. If you look carefully, you will notice
that for an instant all of these threads are drawing at the same time.
About the Calendar computations
The development of this project required operations on dates such as
parsing and computing elapsed days. For this purpose, I implemented a
Calendar class. The source is available at
Calendar.java. If you use this class, please
forward improvements and corrections back to me so that I can
The date parser is as forgiving as possible, and accepts dates in most
forms that are commonly used in the US. For confirmation, the parsed
date and the total elapsed days computation is echoed in the status
A biorhythm is a cyclical pattern of biological activity that begins
at birth. There are three sine wave cycles controlling our Physical,
Emotional and Intellectual highs and lows.
- The physical cycle has a period of 23 days and controls our energy,
vitality, stamina, vigor, endurance and initiative.
When our physical cycle is up, we are more likely to feel better,
be full of energy, and less likely to become ill.
When our physical cycle is down, we tent to tire more easily and are more
apt to catch colds and other illnesses.
- The emotional cycle has a period of 28 days and controls our sensitivity
When our emotional cycle is up, we are more likely to be cheerful, creative,
artistic and sensous.
When this cycle is down, we are more likely to be moody, bad tempered,
irritable and depressed.
- This cycle has a period of 33 days. When it is up we think
quickly, solve problems effectively, do well on tests and retain facts
When it is down, we display poor memory and judgement. We may find it hard
to concentrate. Poor decisions may be made during this period.
Critical or Zero Days
The magnitude of the cycles has no significance except to indicate negative,
zero and positive values. Days in which a curve
crosses the center line are known as critical days.
On these days, you system may be in turmoil. Things are likely to
go wrong and you may be more accident prone.