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
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
use std::collections::HashMap;
use std::sync::{Arc, Mutex};

use faer::sparse::SparseColMat;
use faer_ext::IntoFaer;
use nalgebra as na;
use pyo3::prelude::*;
use rayon::prelude::*;

use crate::{factors, loss_functions, residual_block};

#[pyclass]
pub struct Problem {
    pub total_variable_dimension: usize,
    pub total_residual_dimension: usize,
    residual_blocks: Vec<residual_block::ResidualBlock>,
    pub variable_name_to_col_idx_dict: HashMap<String, usize>,
}
impl Problem {
    pub fn new() -> Problem {
        Problem {
            total_variable_dimension: 0,
            total_residual_dimension: 0,
            residual_blocks: Vec::<residual_block::ResidualBlock>::new(),
            variable_name_to_col_idx_dict: HashMap::<String, usize>::new(),
        }
    }
    pub fn add_residual_block(
        &mut self,
        dim_residual: usize,
        variable_key_size_list: Vec<(String, usize)>,
        factor: Box<dyn factors::Factor + Send>,
        loss_func: Option<Box<dyn loss_functions::Loss + Send>>,
    ) {
        self.residual_blocks.push(residual_block::ResidualBlock {
            dim_residual,
            residual_row_start_idx: self.total_residual_dimension,
            variable_key_list: variable_key_size_list
                .iter()
                .map(|(x, _)| x.to_string())
                .collect(),
            factor,
            loss_func,
        });
        for (key, variable_dimesion) in variable_key_size_list {
            if !self.variable_name_to_col_idx_dict.contains_key(&key) {
                self.variable_name_to_col_idx_dict
                    .insert(key, self.total_variable_dimension);
                self.total_variable_dimension += variable_dimesion;
            }
        }
        self.total_residual_dimension += dim_residual;
    }
    pub fn combine_variables(
        &self,
        variable_key_value_map: &HashMap<String, na::DVector<f64>>,
    ) -> na::DVector<f64> {
        let mut combined_variables = na::DVector::<f64>::zeros(self.total_variable_dimension);
        for (k, v) in variable_key_value_map {
            if let Some(col_idx) = self.variable_name_to_col_idx_dict.get(k) {
                combined_variables
                    .rows_mut(*col_idx, v.shape().0)
                    .copy_from(v);
            };
        }
        return combined_variables;
    }
    pub fn compute_residual_and_jacobian(
        &self,
        variable_key_value_map: &HashMap<String, na::DVector<f64>>,
    ) -> (faer::Mat<f64>, SparseColMat<usize, f64>) {
        // multi
        let total_residual = Arc::new(Mutex::new(na::DVector::<f64>::zeros(
            self.total_residual_dimension,
        )));
        let jacobian_list = Arc::new(Mutex::new(Vec::<(usize, usize, f64)>::new()));

        self.residual_blocks.par_iter().for_each(|residual_block| {
            let mut params = Vec::<na::DVector<f64>>::new();
            let mut variable_local_idx_size_list = Vec::<(usize, usize)>::new();
            let mut count_variable_local_idx: usize = 0;
            for vk in &residual_block.variable_key_list {
                if let Some(param) = variable_key_value_map.get(vk) {
                    params.push(param.clone());
                    variable_local_idx_size_list.push((count_variable_local_idx, param.shape().0));
                    count_variable_local_idx += param.shape().0;
                };
            }
            let (res, jac) = residual_block.jacobian(&params);

            {
                let mut total_residual = total_residual.lock().unwrap();
                total_residual
                    .rows_mut(
                        residual_block.residual_row_start_idx,
                        residual_block.dim_residual,
                    )
                    .copy_from(&res);
            }

            for (i, vk) in residual_block.variable_key_list.iter().enumerate() {
                if let Some(variable_global_idx) = self.variable_name_to_col_idx_dict.get(vk) {
                    let (variable_local_idx, var_size) = variable_local_idx_size_list[i];
                    let variable_jac = jac.view((0, variable_local_idx), (jac.shape().0, var_size));
                    let mut local_jacobian_list = Vec::new();
                    for row_idx in 0..jac.shape().0 {
                        for col_idx in 0..var_size {
                            let global_row_idx = residual_block.residual_row_start_idx + row_idx;
                            let global_col_idx = variable_global_idx + col_idx;
                            let value = variable_jac[(row_idx, col_idx)];
                            local_jacobian_list.push((global_row_idx, global_col_idx, value));
                        }
                    }
                    let mut jacobian_list = jacobian_list.lock().unwrap();
                    jacobian_list.extend(local_jacobian_list);
                }
            }
        });

        let total_residual = Arc::try_unwrap(total_residual)
            .unwrap()
            .into_inner()
            .unwrap();
        let jacobian_list = Arc::try_unwrap(jacobian_list)
            .unwrap()
            .into_inner()
            .unwrap();
        // end

        let residual_faer = total_residual.view_range(.., ..).into_faer().to_owned();
        let jacobian_faer = SparseColMat::try_new_from_triplets(
            self.total_residual_dimension,
            self.total_variable_dimension,
            &jacobian_list,
        )
        .unwrap();
        (residual_faer, jacobian_faer)
    }
}