19 releases (7 breaking)
✓ Uses Rust 2018 edition
|new 0.8.0-beta.1||Nov 5, 2019|
|0.7.0||Sep 30, 2019|
|0.6.1||Jun 16, 2019|
|0.4.1||Sep 15, 2018|
|0.3.0||Jul 31, 2018|
#8 in Machine learning
266 downloads per month
Used in 2 crates
Random variables (RV) for rust. rv offers basic functionality for many probability distributions.
For example, if we wanted to perform a conjugate analysis of Bernoulli trials:
use rv::prelude::*; // Prior over the unknown coin weight. Assume all weights are equally // likely. let prior = Beta::uniform(); // observations generated by a fair coin let obs_fair: Vec<u8> = vec![0, 1, 0, 1, 1, 0, 1]; // observations generated by a coin rigged to always show heads. Note that // we're using `bool`s here. Bernoulli supports mutliple types. let obs_fixed: Vec<bool> = vec![true; 6]; let data_fair: BernoulliData<_> = DataOrSuffStat::Data(&obs_fair); let data_fixed: BernoulliData<_> = DataOrSuffStat::Data(&obs_fixed); // Let's compute the posterior predictive probability (pp) of a heads given // the observations from each coin. let postpred_fair = prior.pp(&1u8, &data_fair); let postpred_fixed = prior.pp(&true, &data_fixed); // The probability of heads should be greater under the all heads data assert!(postpred_fixed > postpred_fair); // We can also get the posteriors let post_fair: Beta = prior.posterior(&data_fair); let post_fixed: Beta = prior.posterior(&data_fixed); // And compare their means let post_mean_fair: f64 = post_fair.mean().unwrap(); let post_mean_fixed: f64 = post_fixed.mean().unwrap(); assert!(post_mean_fixed > post_mean_fair);
Random variables are designed to be flexible. For example, we don't just want a
Beta distribution that works with
f64; we want it to work with a bunch of
use rv::prelude::*; // Beta(0.5, 0.5) let beta = Beta::jeffreys(); let mut rng = rand::thread_rng(); // 100 f64 weights in (0, 1) let f64s: Vec<f64> = beta.sample(100, &mut rng); let pdf_x = beta.ln_pdf(&f64s); // 100 f32 weights in (0, 1) let f32s: Vec<f32> = beta.sample(100, &mut rng); let pdf_y = beta.ln_pdf(&f32s); // 100 Bernoulli distributions -- Beta is a prior on the weight let berns: Vec<Bernoulli> = beta.sample(100, &mut rng); let pdf_bern = beta.ln_pdf(&berns);
For more interesting examples, including use in machine learning, see
- Please create an issue before starting any work. We're far from stable, so we might actually be working on what you want, or we might be working on something that will change the way you might implement it.
- If you plan on implementing a new distribution, implement at least
Support, and either
DiscreteDistr. Of course, more is better!
- Implement new distributions for the appropriate types. For example, don't
Rv<f64>, also implement
Rv<f32>. Check out other distributions to see how it can be done easily with macros.
- Write tests, docs, and doc tests.
rustfmt. We've included a
.rustfmt.tomlin the project directory.