General Information
- Documentation:
- Downloads:
- Dependencies:
Optional Dependencies
colorama: colored column heads in PID indicating failure modes
cython: faster sampling from distributions
hypothesis: random sampling of distributions
jax, jaxlib: JAX-based optimization backend with autodiff support
matplotlib, python-ternary: plotting of various information-theoretic expansions
numdifftools: numerical evaluation of gradients and hessians during optimization
pint: add units to informational values
scikit-learn: faster nearest-neighbor lookups during entropy/mutual information estimation from samples
torch: PyTorch-based optimization backend with autodiff and GPU support
xarray:
Distributionclass for labeled, algebra-friendly distributions
- Code and bug tracker:
- License:
BSD 3-Clause, see LICENSE.txt for details.
Quickstart
The basic usage of dit corresponds to creating distributions, modifying
them if need be, and then computing properties of those distributions.
First, we import:
In [1]: import dit
Suppose we have a really thick coin, one so thick that there is a reasonable
chance of it landing on its edge. Here is how we might represent the coin in
dit.
In [2]: d = dit.Distribution(['H', 'T', 'E'], [.4, .4, .2])
In [3]: print(d)
Class: Distribution
Alphabet: (('E', 'H', 'T'),)
Base: linear
x p(X0)
('E',) 1/5
('H',) 2/5
('T',) 2/5
Calculate the probability of \(H\) and also of the combination: \(H~\mathbf{or}~T\).
In [4]: d['H']
Out[4]: 0.4
In [5]: d.event_probability(['H','T'])
Out[5]: 0.8
Calculate the Shannon entropy and extropy of the joint distribution.
In [6]: dit.shannon.entropy(d)
Out[6]: 1.5219280948873621
In [7]: dit.other.extropy(d)
Out[7]: 1.1419011889093373
Create a distribution representing the \(\mathbf{xor}\) logic function. Here, we have two inputs, \(X\) and \(Y\), and then an output \(Z = \mathbf{xor}(X,Y)\).
In [8]: import dit.example_dists
In [9]: d = dit.example_dists.Xor()
In [10]: d.set_rv_names(['X', 'Y', 'Z'])
In [11]: print(d)
Class: Distribution
Alphabet: (('0', '1'), ('0', '1'), ('0', '1'))
Base: linear
x p(X,Y,Z)
('0', '0', '0') 1/4
('0', '1', '1') 1/4
('1', '0', '1') 1/4
('1', '1', '0') 1/4
Calculate the Shannon mutual informations \(\I[X:Z]\), \(\I[Y:Z]\), and \(\I[X,Y:Z]\).
In [12]: dit.shannon.mutual_information(d, ['X'], ['Z'])
Out[12]: 0.0
In [13]: dit.shannon.mutual_information(d, ['Y'], ['Z'])
Out[13]: 0.0
In [14]: dit.shannon.mutual_information(d, ['X', 'Y'], ['Z'])
Out[14]: 1.0
Calculate the marginal distribution \(P(X,Z)\). Then print its probabilities as fractions, showing the mask.
In [15]: d2 = d.marginal(['X', 'Z'])
In [16]: print(d2.to_string(show_mask=True, exact=True))
Class: Distribution
Alphabet: (('0', '1'), ('0', '1'))
Base: linear
x p(X,Z)
('0', '0') 1/4
('0', '1') 1/4
('1', '0') 1/4
('1', '1') 1/4
Convert the distribution probabilities to log (base 3.5) probabilities, and access its probability mass function.
In [17]: d2.set_base(3.5)
In [18]: d2.pmf
Out[18]: array([-1.10658951, -1.10658951, -1.10658951, -1.10658951])
Draw 5 random samples from this distribution.
In [19]: d2.rand(5)
Out[19]: [('0', '1'), ('1', '0'), ('0', '0'), ('0', '1'), ('0', '0')]
Enjoy!
Install
The easiest way to install is:
pip install dit
If you want to install dit within a conda environment, you can simply do:
conda install -c conda-forge dit
For development, we recommend uv:
git clone https://github.com/dit/dit.git
cd dit
uv sync --extra dev
This installs dit in editable mode with all development dependencies
(tests, docs, linting, type checking, and optional backends).
To install specific optional extras:
# JAX optimization backend
pip install "dit[jax]"
# PyTorch optimization backend
pip install "dit[torch]"