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

use crate::{number::Number, Matrix};

pub trait SubMatrix<T>: Send + Sync {
    fn size(&self) -> (usize, usize);
    fn index(&self, i: usize, j: usize) -> T;
}

impl<T> SubMatrix<T> for T
where
    T: Number,
{
    fn size(&self) -> (usize, usize) {
        (1usize, 1usize)
    }

    fn index(&self, _: usize, _: usize) -> T {
        *self
    }
}

impl<T> SubMatrix<T> for Matrix<T>
where
    T: Number,
{
    fn size(&self) -> (usize, usize) {
        (self.rows(), self.cols())
    }

    fn index(&self, i: usize, j: usize) -> T {
        self[(i, j)]
    }
}

impl<T> SubMatrix<T> for &Matrix<T>
where
    T: Number,
{
    fn size(&self) -> (usize, usize) {
        (self.rows(), self.cols())
    }

    fn index(&self, i: usize, j: usize) -> T {
        self[(i, j)]
    }
}