Trait matrixable::req::InPlace

source ·

pub trait InPlace<M: MatrixMutExt>: Sized {
    // Required method
    fn in_place(&self, m: &mut M);
}

Expand description

A trait for in-place modification of matrices. The following example shows the implementation of the SortBy strategy used in this crate.

§Example

use matrixable::req::InPlace;
use matrixable::MatrixMutExt;

pub struct SortBy<T> (fn(&T, &T) -> bool);

impl<M: MatrixMutExt> InPlace<M> for SortBy<M::Element> {
    fn in_place(&self, m: &mut M) {
        let mut im;
        let mut min_or_max;
        let mut cmp;

        for i in 0..(m.size() - 1) {
            im = i;
            min_or_max = m.get_nth(i).unwrap();
            for j in (i+1)..m.size() {
                cmp = m.get_nth(j).unwrap();
                if !(self.0)(min_or_max, cmp) {
                      im = j;
                      min_or_max = cmp;
                }
            }
            m.swapn(im, i);
        }
    }
} 

let mut m = [ 
    [4,  5,  6],
    [9,  1, 20],
    [4, 12, -1]
];

let sort = SortBy(|a, b| a < b);

m.in_place(sort);
 
assert_eq!(m, [
    [-1,  1,  4],
    [ 4,  5,  6],
    [ 9, 12, 20]
]);