hipvs/ivf_flat/mod.rs
1/*
2 * Copyright (c) 2024, NVIDIA CORPORATION.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17//! The IVF-Flat method is an ANN algorithm. It uses an inverted file index (IVF) with
18//! unmodified (that is, flat) vectors. This algorithm provides simple knobs to reduce
19//! the overall search space and to trade-off accuracy for speed.
20//!
21//! Example:
22//! ```
23//!
24//! use hipvs::ivf_flat::{Index, IndexParams, SearchParams};
25//! use hipvs::{ManagedTensor, Resources, Result};
26//!
27//! use ndarray::s;
28//! use ndarray_rand::rand_distr::Uniform;
29//! use ndarray_rand::RandomExt;
30//!
31//! fn ivf_flat_example() -> Result<()> {
32//! let res = Resources::new()?;
33//!
34//! // Create a new random dataset to index
35//! let n_datapoints = 65536;
36//! let n_features = 512;
37//! let dataset =
38//! ndarray::Array::<f32, _>::random((n_datapoints, n_features), Uniform::new(0., 1.0));
39//!
40//! // build the ivf-flat index
41//! let build_params = IndexParams::new()?;
42//! let index = Index::build(&res, &build_params, &dataset)?;
43//! println!(
44//! "Indexed {}x{} datapoints into ivf-flat index",
45//! n_datapoints, n_features
46//! );
47//!
48//! // use the first 4 points from the dataset as queries : will test that we get them back
49//! // as their own nearest neighbor
50//! let n_queries = 4;
51//! let queries = dataset.slice(s![0..n_queries, ..]);
52//!
53//! let k = 10;
54//!
55//! // Ivf-Flat search API requires queries and outputs to be on device memory
56//! // copy query data over, and allocate new device memory for the distances/ neighbors
57//! // outputs
58//! let queries = ManagedTensor::from(&queries).to_device(&res)?;
59//! let mut neighbors_host = ndarray::Array::<u32, _>::zeros((n_queries, k));
60//! let neighbors = ManagedTensor::from(&neighbors_host).to_device(&res)?;
61//!
62//! let mut distances_host = ndarray::Array::<f32, _>::zeros((n_queries, k));
63//! let distances = ManagedTensor::from(&distances_host).to_device(&res)?;
64//!
65//! let search_params = SearchParams::new()?;
66//!
67//! index.search(&res, &search_params, &queries, &neighbors, &distances)?;
68//!
69//! // Copy back to host memory
70//! distances.to_host(&res, &mut distances_host)?;
71//! neighbors.to_host(&res, &mut neighbors_host)?;
72//!
73//! // nearest neighbors should be themselves, since queries are from the
74//! // dataset
75//! println!("Neighbors {:?}", neighbors_host);
76//! println!("Distances {:?}", distances_host);
77//! Ok(())
78//! }
79//! ```
80
81mod index;
82mod index_params;
83mod search_params;
84
85pub use index::Index;
86pub use index_params::IndexParams;
87pub use search_params::SearchParams;