.. currentmodule:: skopt
Scikit-Optimize, or skopt
, is a simple and efficient library to
minimize (very) expensive and noisy black-box functions. It implements
several methods for sequential model-based optimization. skopt
aims
to be accessible and easy to use in many contexts.
The library is built on top of NumPy, SciPy and Scikit-Learn.
We do not perform gradient-based optimization. For gradient-based
optimization algorithms look at
scipy.optimize
here.
Approximated objective function after 50 iterations of :class:`gp_minimize`. Plot made using :class:`plots.plot_objective`.
Find the minimum of the noisy function f(x)
over the range -2 < x < 2
with :class:`skopt`:
>>> import numpy as np >>> from skopt import gp_minimize >>> np.random.seed(123) >>> def f(x): ... return (np.sin(5 * x[0]) * (1 - np.tanh(x[0] ** 2)) * ... np.random.randn() * 0.1) >>> >>> res = gp_minimize(f, [(-2.0, 2.0)], n_calls=20) >>> print("x*=%.2f f(x*)=%.2f" % (res.x[0], res.fun)) x*=0.85 f(x*)=-0.06
For more control over the optimization loop you can use the :class:`skopt.Optimizer` class:
>>> from skopt import Optimizer >>> opt = Optimizer([(-2.0, 2.0)]) >>> >>> for i in range(20): ... suggested = opt.ask() ... y = f(suggested) ... res = opt.tell(suggested, y) >>> print("x*=%.2f f(x*)=%.2f" % (res.x[0], res.fun)) x*=0.27 f(x*)=-0.15
For more read our :ref:`sphx_glr_auto_examples_bayesian-optimization.py` and the other examples.