<pre>
class Monitor

InputReal x, y, z;  // plant output
OutputBoolean wy;
Boolean wz;
initial equation
wy = false;
equation
wz = (time > 50) and (x < 0.6*y) and (x + y > 0.3*z);
algorithm
when edge(wz) then
wy := true;
end when;
end Monitor;
</pre>
