nautilus_analysis/python/statistics/tracking_error.rs
1// -------------------------------------------------------------------------------------------------
2// Copyright (C) 2015-2026 Nautech Systems Pty Ltd. All rights reserved.
3// https://nautechsystems.io
4//
5// Licensed under the GNU Lesser General Public License Version 3.0 (the "License");
6// You may not use this file except in compliance with the License.
7// You may obtain a copy of the License at https://www.gnu.org/licenses/lgpl-3.0.en.html
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14// -------------------------------------------------------------------------------------------------
15
16use std::collections::BTreeMap;
17
18use nautilus_model::position::Position;
19use pyo3::prelude::*;
20
21use super::transform_returns;
22use crate::{statistic::PortfolioStatistic, statistics::tracking_error::TrackingError};
23
24#[pymethods]
25#[pyo3_stub_gen::derive::gen_stub_pymethods]
26impl TrackingError {
27 /// Calculates the tracking error of portfolio returns relative to a benchmark.
28 ///
29 /// Tracking error is the volatility of the active return (portfolio minus benchmark):
30 ///
31 /// `TE = std(active) * sqrt(period)`
32 ///
33 /// where `active_i = portfolio_i - benchmark_i`, `std` uses Bessel's correction
34 /// (`ddof = 1`), and the result is annualized by the square root of the specified period
35 /// (default: 252 trading days).
36 ///
37 /// # References
38 ///
39 /// - Roll, R. (1992). "A Mean/Variance Analysis of Tracking Error".
40 /// *Journal of Portfolio Management*, 18(4), 13-22.
41 /// - CFA Institute Investment Foundations, 3rd Edition
42 #[new]
43 #[pyo3(signature = (period=None))]
44 fn py_new(period: Option<usize>) -> Self {
45 Self::new(period)
46 }
47
48 fn __repr__(&self) -> String {
49 self.to_string()
50 }
51
52 #[getter]
53 #[pyo3(name = "name")]
54 fn py_name(&self) -> String {
55 self.name()
56 }
57
58 #[pyo3(name = "calculate_from_returns")]
59 fn py_calculate_from_returns(&self, _returns: BTreeMap<u64, f64>) -> Option<f64> {
60 None
61 }
62
63 #[pyo3(name = "calculate_from_realized_pnls")]
64 fn py_calculate_from_realized_pnls(&self, _realized_pnls: Vec<f64>) -> Option<f64> {
65 None
66 }
67
68 #[pyo3(name = "calculate_from_positions")]
69 fn py_calculate_from_positions(&self, _positions: Vec<Position>) -> Option<f64> {
70 None
71 }
72
73 #[pyo3(name = "calculate_from_returns_with_benchmark")]
74 #[expect(clippy::needless_pass_by_value)]
75 fn py_calculate_from_returns_with_benchmark(
76 &self,
77 returns: BTreeMap<u64, f64>,
78 benchmark: BTreeMap<u64, f64>,
79 ) -> Option<f64> {
80 self.calculate_from_returns_with_benchmark(
81 &transform_returns(&returns),
82 &transform_returns(&benchmark),
83 )
84 }
85}