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Welcome to ConfigSpace's documentation!

ConfigSpace is a simple python package to manage configuration spaces for algorithm configuration and hyperparameter optimization tasks. It includes various modules to translate between different text formats for configuration space descriptions.

ConfigSpace is often used in AutoML tools such as SMAC3, BOHB, auto-sklearn. To read more about our group and projects, visit our homepage AutoML.org.

This documentation explains how to use ConfigSpace and demonstrates its features. In the quickstart, you will see how to set up a ConfiguratonSpace and add hyperparameters of different types to it. Besides containing hyperparameters, ConfigurationSpace can contain constraints such as conditions and forbidden clauses. Those are introduced in the user guide

New in 1.1!

In ConfigSpace 1.1, we have removed the dependancy on Cython while even improving the performance!

• Should now install anywhere.
• You can now use your editor to jump to definition and see the source code.
• Contribute more easily!

There is no also better support in Categorical, Ordinal and Constant hyperparameters, for arbitrary values, for example:

from dataclasses import dataclass
from ConfigSpace import ConfigurationSpace, Constant

@dataclass
class A:
    a: int

def f() -> None:
    return None

cs = ConfigurationSpace({
    "cat": [True, False, None],
    "othercat": [A(1), f],
    "constant": Constant("constant": (24, 25)),
})

With this, we have also deprecated many of the previous functions, simplifying the API where possible or improving it's clarity. We have tried hard to keep everything backwards compatible, and also recommend the new functionality to use!

We've also made some strides towards extensibilty of ConfigSpace, making it simpler to define you own hyperparamter types. Please see the hyperparameter reference page for more.

Warning

One notable hard removal is the use of the "q" parameter to numerical parameters. We recommend using an Ordinal distribution where possible. Please let us know if this effects you and we can help migrate where possible.

Getting Started

Create a simple ConfigurationSpace and then sample a Configuration from it.

from ConfigSpace import ConfigurationSpace

cs = ConfigurationSpace({
    "myfloat": (0.1, 1.5),                # Uniform Float
    "myint": (2, 10),                     # Uniform Integer
    "species": ["mouse", "cat", "dog"],   # Categorical
})
configs = cs.sample_configuration(2)
print(configs)

[Configuration(values={
  'myfloat': 1.0258528551816,
  'myint': 4,
  'species': np.str_('mouse'),
}), Configuration(values={
  'myfloat': 0.6166799378983,
  'myint': 10,
  'species': np.str_('mouse'),
})]

Use Float, Integer, and Categorical to define hyperparameters and define how sampling is done.

from ConfigSpace import ConfigurationSpace, Integer, Float, Categorical, Normal

cs = ConfigurationSpace(
    name="myspace",
    seed=1234,
    space={
        "a": Float("a", bounds=(0.1, 1.5), distribution=Normal(1, 0.5)),
        "b": Integer("b", bounds=(1, 10_00), log=True, default=100),
        "c": Categorical("c", ["mouse", "cat", "dog"], weights=[2, 1, 1]),
    },
)
configs = cs.sample_configuration(2)
print(configs)

[Configuration(values={
  'a': 0.561388655784,
  'b': 6,
  'c': np.str_('mouse'),
}), Configuration(values={
  'a': 1.0464213025979,
  'b': 6,
  'c': np.str_('cat'),
})]

Maximum flexibility with conditionals, see the user guide for more information.

from ConfigSpace import Categorical, ConfigurationSpace, EqualsCondition, Float

cs = ConfigurationSpace(seed=1234)

c = Categorical("c1", items=["a", "b"])
f = Float("f1", bounds=(1.0, 10.0))

# A condition where `f` is only active if `c` is equal to `a` when sampled
cond = EqualsCondition(f, c, "a")

# Add them explicitly to the configuration space
cs.add([c, f])
cs.add(cond)

print(cs)

Configuration space object:
  Hyperparameters:
    c1, Type: Categorical, Choices: {a, b}, Default: a
    f1, Type: UniformFloat, Range: [1.0, 10.0], Default: 5.5
  Conditions:
    f1 | c1 == 'a'

Installation

ConfigSpace requires Python 3.8 or higher and can be installed directly from the Python Package Index (PyPI) using pip.

pip install ConfigSpace

Citing ConfigSpace

 @article{
     title   = {BOAH: A Tool Suite for Multi-Fidelity Bayesian Optimization & Analysis of Hyperparameters},
     author  = {M. Lindauer and K. Eggensperger and M. Feurer and A. Biedenkapp and J. Marben and P. Müller and F. Hutter},
     journal = {arXiv:1908.06756 {[cs.LG]}},
     date    = {2019},
 }