def garage_counter(ploting=True):
"""Example 3.4, p.49 [LS11], for M=2
no state variables in this Finite-State Machine
"""
m = trs.Mealy()
m.add_inputs([
['up', {'present', 'absent'}],
['down', {'present', 'absent'}]
])
m.add_outputs([
('count', range(3) )
])
m.states.add_from(range(3) )
m.states.initial.add(0)
m.transitions.add(0, 1, up='present', down='absent', count=1)
m.transitions.add(1, 0, up='absent', down='present', count=0)
m.transitions.add(1, 2, up='present', down='absent', count=2)
m.transitions.add(2, 1, up='absent', down='present', count=1)
if ploting:
m.plot()
return m
def pedestrians():
"""Example 2.14, p.63 [LS11]
"""
m = trs.Mealy()
m.add_inputs([
('sigR', mc.pure),
('sigG', mc.pure),
('sigY', mc.pure)
])
m.add_outputs([
('pedestrian', mc.pure)
])
m.states.add_from(['none', 'waiting', 'crossing'] )
m.states.initial.add('crossing')
for sigR in mc.pure:
for sigG in mc.pure:
for sigY in mc.pure:
m.transitions.add(
'none', 'none',
sigR=sigR, sigG=sigG, sigY=sigY,
pedestrian='absent'
)
m.transitions.add(
'none', 'waiting',
sigR=sigR, sigG=sigG, sigY=sigY,
pedestrian='present'
)
m.transitions.add(
'waiting', 'crossing',
sigR='present', sigG='absent', sigY='absent',
pedestrian='absent'
)
m.transitions.add(
'crossing', 'none',
sigR='absent', sigG='present', sigY='absent',
pedestrian='absent'
)
m.plot()
return m
def thermostat_with_hysteresis():
"""Example 3.5, p.50 [LS11]
"""
class temperature_type():
def is_valid_value(x):
if not isinstance(x, [float, int]):
raise TypeError('Input temperature must be float.')
def __contains__(self, guard):
# when properly implemented, do appropriate syntactic check
if isinstance(guard, float):
return True
return False
m = trs.Mealy()
m.add_inputs([('temperature', ) ])
def traffic_light():
m = trs.Mealy()
pure_signal = {'present', 'absent'}
m.add_inputs([('tick', pure_signal) ])
m.add_outputs([('go', pure_signal), ('stop', pure_signal) ])
m.states.add_from(['red', 'green', 'yellow'])
m.states.initial.add('red')
p = 'present'
a = 'absent'
m.transitions.add('red', 'green', tick=p, go=p, stop=a)
m.transitions.add('green', 'yellow', tick=p, go=a, stop=p)
m.transitions.add('yellow', 'red', tick=p, go=a, stop=p)
m.plot()
return m
