Clock functions
instance clock
The clock object offers basic time functions. A clock object is
created automatically when the experiment starts.
Example:
# Get the timestamp before and after sleeping for 1000 ms
t0 = clock.time()
clock.sleep(1000)
t1 = clock.time()
time_passed = t1 - t0
print(u'This should be 1000: %s' % time_passed)
function clock.loop_for(ms, throttle=None, t0=None)
New in v3.2.0
An iterator that loops for a fixed time.
Example:
for ms in clock.loop_for(100, throttle=10):
print(ms)
Arguments:
ms-- The number of milliseconds to loop for.- Type: int. float
Keywords:
throttle-- A period to sleep for in between each iteration.- Type: NoneType, float, int
- Default: None
t0-- A starting time. IfNone, the starting time is the moment at which the iteration starts.- Type: NoneType, float, int
- Default: None
Returns:
An Iterator over times in milliseconds that have passed since t0.
function clock.once_in_a_while(ms=1000)
New in v3.2.0
Periodically returns True. This is mostly useful for executing
code (e.g. within a for loop) that should only be executed once
in a while.
Example:
for i in range(1000000):
if clock.once_in_a_while(ms=50):
# Execute this code only once every 50 ms
print(clock.time())
Keywords:
ms-- The minimum waiting period.- Type: int, float
- Default: 1000
Returns:
True after (at least) the minimum waiting period has
passed since the last call to Clock.once_in_a_while(), or
False otherwise.
- Type: bool
function clock.sleep(ms)
Sleeps (pauses) for a period.
Example:
# Create two canvas objects ...
my_canvas1 = Canvas()
my_canvas1.text(u'1')
my_canvas2 = Canvas()
my_canvas2.text(u'2')
# ... and show them with 1 s in between
my_canvas1.show()
clock.sleep(1000)
my_canvas2.show()
Arguments:
ms-- The number of milliseconds to sleep for.- Type: int, float
function clock.time()
Gives a current timestamp in milliseconds. The absolute meaning of the timestamp (i.e. when it was 0) depends on the backend.
Example:
t = clock.time()
print(u'The current time is %f' % t)
Returns:
A timestamp.
- Type: float