 
generalized bean curve


last updated: 20040505 
The curve is a generalization of the bean
curve (a=b=3).
For a=b=1 and a=b=2 the curve is the circle.
We see the following:
 the bean curve_{a, b} is equivalent to the bean curve_{b, a}
 the order of the curve is max(a,b) (a and b both uneven) or 1/2 max (a,b)
(a or b even)
 when a or b is even, the curve is compound of two symmetric bean curves
 the values for a and b define how much the curve is pressed in from a
circle towards a right angle figure, a for the vertical part, b for the
horizontal part
