Custom Callbacks

Callbacks can hook at the following six events

class MyCallback(pyhopper.callbacks.Callback):
    def on_search_start(self, search: pyhopper.Search):
        pass # Called at the beginning of the search process

    def on_evaluate_start(self, param: dict, info: pyhopper.ParamInfo):
        pass # Called after parameter `param` is sampled

    def on_evaluate_end(self, param: dict, f: float, info: pyhopper.ParamInfo):
        pass # Called after parameter `param` is evaluated to the value f

    def on_evaluate_pruned(self, param: dict, info: pyhopper.ParamInfo):
        pass # Called if the evaluation of parameter `param` is pruned

    def on_new_best(self, new_best: dict, f: float, info: pyhopper.ParamInfo):
        pass # Called if a new best parameter `new_best` with value f was found

    def on_search_end(self, history: pyhopper.History):
        pass # Called at the end of the search process

The type pyhopper.ParamInfo() stores information about the particular candidate such as how it was sampled (random seeding, local sampling, manually added), when the candidate was sampled (as a time timestamp) and when its evaluation was finished. For instance,

import datetime as dt
import time

class MyCallback(pyhopper.callbacks.Callback):
    def on_evaluate_start(self, param: dict, info: pyhopper.ParamInfo):
        print(
            f"{param['x']} sampled at {dt.datetime.fromtimestamp(info.sampled_at):%Y %B %d - %H:%m}"
        )

    def on_evaluate_end(self, param: dict, f: float, info: pyhopper.ParamInfo):
        print(
            f"{param['x']} finished at {dt.datetime.fromtimestamp(info.finished_at):%Y %B %d - %H:%m}"
        )
        print(f"Took {info.finished_at-info.sampled_at:0.1f} seconds")

def of(param):
    time.sleep(1)
    return np.random.default_rng().random()


search = pyhopper.Search(
    {
        "x": pyhopper.int(0, 10),
    },
)
r1 = search.run(
    of,
    "max",
    steps=3,
    quiet=True,
    callbacks=[MyCallback()],
)

outputs

> 5 sampled at 2021 July 06 - 14:07
> 5 finished at 2021 July 06 - 14:07
> Took 1.0 seconds
> 3 sampled at 2021 July 06 - 14:07
> 3 finished at 2021 July 06 - 14:07
> Took 1.0 seconds
> 6 sampled at 2021 July 06 - 14:07
> 6 finished at 2021 July 06 - 14:07
> Took 1.0 seconds