diffsol 0.12.4

A library for solving ordinary differential equations (ODEs) in Rust.
Documentation 
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
140
141
142
143
144
145
146
147
148
149
150
151

use std::cell::RefCell;

use crate::{
    find_jacobian_non_zeros, jacobian::JacobianColoring, Matrix, MatrixSparsity, NonLinearOp,
    NonLinearOpJacobian, Op,
};

use super::{BuilderOp, OpStatistics, ParameterisedOp};

pub struct Closure<M, F, G>
where
    M: Matrix,
    F: Fn(&M::V, &M::V, M::T, &mut M::V),
    G: Fn(&M::V, &M::V, M::T, &M::V, &mut M::V),
{
    func: F,
    jacobian_action: G,
    nstates: usize,
    nout: usize,
    nparams: usize,
    coloring: Option<JacobianColoring<M>>,
    sparsity: Option<M::Sparsity>,
    statistics: RefCell<OpStatistics>,
    ctx: M::C,
}

impl<M, F, G> Closure<M, F, G>
where
    M: Matrix,
    F: Fn(&M::V, &M::V, M::T, &mut M::V),
    G: Fn(&M::V, &M::V, M::T, &M::V, &mut M::V),
{
    pub fn new(
        func: F,
        jacobian_action: G,
        nstates: usize,
        nout: usize,
        nparams: usize,
        ctx: M::C,
    ) -> Self {
        Self {
            func,
            jacobian_action,
            nstates,
            nparams,
            nout,
            statistics: RefCell::new(OpStatistics::default()),
            coloring: None,
            sparsity: None,
            ctx,
        }
    }
    pub fn calculate_sparsity(&mut self, y0: &M::V, t0: M::T, p: &M::V) {
        let param_op = ParameterisedOp { op: self, p };
        let non_zeros = find_jacobian_non_zeros(&param_op, y0, t0);
        self.sparsity = Some(
            MatrixSparsity::try_from_indices(self.nout(), self.nstates(), non_zeros.clone())
                .expect("invalid sparsity pattern"),
        );
        self.coloring = Some(JacobianColoring::new(
            self.sparsity.as_ref().unwrap(),
            &non_zeros,
            self.ctx.clone(),
        ));
    }
}

impl<M, F, G> BuilderOp for Closure<M, F, G>
where
    M: Matrix,
    F: Fn(&M::V, &M::V, M::T, &mut M::V),
    G: Fn(&M::V, &M::V, M::T, &M::V, &mut M::V),
{
    fn calculate_sparsity(&mut self, y0: &M::V, t0: M::T, p: &M::V) {
        self.calculate_sparsity(y0, t0, p);
    }

    fn set_nstates(&mut self, nstates: usize) {
        self.nstates = nstates;
    }
    fn set_nout(&mut self, nout: usize) {
        self.nout = nout;
    }
    fn set_nparams(&mut self, nparams: usize) {
        self.nparams = nparams;
    }
}

impl<M, F, G> Op for Closure<M, F, G>
where
    M: Matrix,
    F: Fn(&M::V, &M::V, M::T, &mut M::V),
    G: Fn(&M::V, &M::V, M::T, &M::V, &mut M::V),
{
    type V = M::V;
    type T = M::T;
    type M = M;
    type C = M::C;

    fn context(&self) -> &Self::C {
        &self.ctx
    }

    fn nstates(&self) -> usize {
        self.nstates
    }
    fn nout(&self) -> usize {
        self.nout
    }
    fn nparams(&self) -> usize {
        self.nparams
    }
    fn statistics(&self) -> OpStatistics {
        self.statistics.borrow().clone()
    }
}

impl<M, F, G> NonLinearOp for ParameterisedOp<'_, Closure<M, F, G>>
where
    M: Matrix,
    F: Fn(&M::V, &M::V, M::T, &mut M::V),
    G: Fn(&M::V, &M::V, M::T, &M::V, &mut M::V),
{
    fn call_inplace(&self, x: &M::V, t: M::T, y: &mut M::V) {
        self.op.statistics.borrow_mut().increment_call();
        (self.op.func)(x, self.p, t, y)
    }
}

impl<M, F, G> NonLinearOpJacobian for ParameterisedOp<'_, Closure<M, F, G>>
where
    M: Matrix,
    F: Fn(&M::V, &M::V, M::T, &mut M::V),
    G: Fn(&M::V, &M::V, M::T, &M::V, &mut M::V),
{
    fn jac_mul_inplace(&self, x: &M::V, t: M::T, v: &M::V, y: &mut M::V) {
        self.op.statistics.borrow_mut().increment_jac_mul();
        (self.op.jacobian_action)(x, self.p, t, v, y)
    }
    fn jacobian_inplace(&self, x: &Self::V, t: Self::T, y: &mut Self::M) {
        self.op.statistics.borrow_mut().increment_matrix();
        if let Some(coloring) = self.op.coloring.as_ref() {
            coloring.jacobian_inplace(self, x, t, y);
        } else {
            self._default_jacobian_inplace(x, t, y);
        }
    }
    fn jacobian_sparsity(&self) -> Option<<Self::M as Matrix>::Sparsity> {
        self.op.sparsity.clone()
    }
}