"""This example demonstrates the usage of Nevergrad with Ray Tune.
It also checks that it is usable with a separate scheduler.
"""
import time
from ray import tune
from ray.tune.suggest import ConcurrencyLimiter
from ray.tune.schedulers import AsyncHyperBandScheduler
from ray.tune.suggest.nevergrad import NevergradSearch
def evaluation_fn(step, width, height):
return (0.1 + width * step / 100)**(-1) + height * 0.1
def easy_objective(config):
# Hyperparameters
width, height = config["width"], config["height"]
for step in range(config["steps"]):
# Iterative training function - can be any arbitrary training procedure
intermediate_score = evaluation_fn(step, width, height)
# Feed the score back back to Tune.
tune.report(iterations=step, mean_loss=intermediate_score)
time.sleep(0.1)
if __name__ == "__main__":
import argparse
import nevergrad as ng
parser = argparse.ArgumentParser()
parser.add_argument(
"--smoke-test", action="store_true", help="Finish quickly for testing")
parser.add_argument(
"--server-address",
type=str,
default=None,
required=False,
help="The address of server to connect to if using "
"Ray Client.")
args, _ = parser.parse_known_args()
if args.server_address:
import ray
ray.init(f"ray://{args.server_address}")
# Optional: Pass the parameter space yourself
# space = ng.p.Dict(
# width=ng.p.Scalar(lower=0, upper=20),
# height=ng.p.Scalar(lower=-100, upper=100),
# activation=ng.p.Choice(choices=["relu", "tanh"])
# )
algo = NevergradSearch(
optimizer=ng.optimizers.OnePlusOne,
# space=space, # If you want to set the space manually
)
algo = ConcurrencyLimiter(algo, max_concurrent=4)
scheduler = AsyncHyperBandScheduler()
analysis = tune.run(
easy_objective,
metric="mean_loss",
mode="min",
name="nevergrad",
search_alg=algo,
scheduler=scheduler,
num_samples=10 if args.smoke_test else 50,
config={
"steps": 100,
"width": tune.uniform(0, 20),
"height": tune.uniform(-100, 100),
"activation": tune.choice(["relu", "tanh"])
})
print("Best hyperparameters found were: ", analysis.best_config)
