public/subjects/matrix_determinant

matrix_determinant

Instructions

Write a matrix_determinant function that receives a 3x3 matrix ([[isize; 3]; 3]) and returns its determinant (isize).

This is how you calculate a 2x2 matrix determinant:

|a b|
|c d|

a*d - b*c

To calculate a 3x3 matrix determinant (below) you have to take 'a' and multiply it by the determinant of the matrix you get if you get rid of 'a' column and row. Then you subtract the multiplication of 'b' and the determinant of the matrix you get if you get rid of 'b' column and row. And finally, you do the same process for 'c' and add it to the previous result.

|a b c|
|d e f|
|g h i|

Expected Function

pub fn matrix_determinant(matrix: [[isize; 3]; 3]) -> isize {

}

Example

Here is a program to test your function:

fn main() {
    let matrix = [[1, 2, 4], [2, -1, 3], [4, 0, 1]];

    println!(
        "The determinant of the matrix:\n|1  2  4|\n|2 -1  3|  = {}\n|4  0  1|",
        matrix_determinant(matr)
    );
}

And its output:

$ cargo run
The determinant of the matrix:
|1  2  4|
|2 -1  3|  = 35
|4  0  1|
$