Schedulers

Schedulers allow to update parameters of the dynamic. Most commonly, one may want to adjust the heat parameter \(\alpha\) during the iteration. The base class is cbx.scheduler.param_update and all schedulers are derived from it.

The function that performs the update is update. The scheduler accesses the parameters of the dynamic from the outside, therefore the dynamic needs to be passed to the update function.

The easiest scheduler multiply simply multiplies the specified value by a constant.

>>> from cbx.dynamics import CBXDynamic
>>> from cbx.scheduler import multiply
>>> dyn = CBXDynamic(lambda x:x**2, d=1, alpha=1.0)
>>> sched = multiply(name='alpha', factor=0.5)
>>> sched.update(dyn)
>>> print(dyn.alpha)
0.5

Specifying multiple updates

If you want to specify multiple parameter updates, you can use the class scheduler which allows you to pass multiple scheduler. It also implements an update function, which uses the update function of the individual schedulers.

>>> from cbx.dynamics import CBXDynamic
>>> from cbx.scheduler import scheduler, multiply
>>> dyn = CBXDynamic(lambda x:x**2, d=1, alpha=1.0, dt=0.5)
>>> sched = schedulr([multiply(name='dt', factor=0.5), multiply(name='alpha', factor=0.5)])
>>> sched.update(dyn)
>>> print(dyn.alpha)
>>> print(dyn.dt)
0.5
0.25