1.1 - Selection of a rhythmic case

We remember that we have introduced the four rhythmic constants $w,x,y,z$. In base of the values of $b$ and $c$, two of theseone constants $(u_1, u_2)$, are selected, in relation to the following rules:

	(couple $u_1, u_2$)
$b$ even, $c$ even	$z, y$
$b$ even, $c$ odd	$z, x$
$b$ odd, $c$ even	$y, x$
$b$ odd, $c$ odd	$w, x$

Therefore we have created a second couple of rhythmic values $(v_1, v_2)$ according to the following rule: if $c < b$ then $v_1 = u_1, v_2 = u_2$ if $c > b$ then $v_1 = u_2, v_2 = u_1$

The value of $O$ is finally calculated in base of the couple $(v1, v2)$ and to the values of $b, c, j, k, l$.