1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the License for the
// specific language governing permissions and limitations
// under the License.
//! Theta sketch implementation for cardinality estimation.
//!
//! Theta sketch is a generalization of the Kth Minimum Value (KMV) sketch that uses
//! a hash table to store retained entries and a theta parameter (sampling threshold)
//! to control memory usage. When the hash table reaches capacity, theta is reduced
//! to maintain the nominal size k.
//!
//! # Overview
//!
//! Theta sketches provide approximate distinct count (cardinality) estimation with
//! configurable accuracy and memory usage. The implementation supports:
//!
//! - **ThetaSketch**: Mutable sketch for building from input data
//!
//! # Usage
//!
//! ```rust
//! # use datasketches::theta::ThetaSketch;
//! let mut sketch = ThetaSketch::builder().build();
//! sketch.update("apple");
//! assert!(sketch.estimate() >= 1.0);
//! ```
pub use ThetaSketch;
pub use ThetaSketchBuilder;