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Rust dev

• 250111 Rust Matrix구현.시리즈(C언어와 비교)

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Rust로 Matrix를 구현하겠습니다.

   // Your Rust code here
fn matrix_multiply(
    matrix: [[i32; 3]; 3],
    mul: [[i32; 1]; 3]
    ) -> [[i32; 1]; 3] 
    {
    let mut result = [[0; 1]; 3];

    for i in 0..3 {
        for j in 0..1 {
            for k in 0..3 {
                result[i][j] += matrix[i][k] * mul[k][j];
            }
        }
    }

    result
}

fn main() {
    #[rustfmt::skip]
    let matrix_2d = [
        [1, 2, 3],
        [4, 5, 6],
        [7, 8, 9]
    ];
    #[rustfmt::skip]
    let mat_mul = [
        [1],
        [2],
        [3]
    ];

    let mat_result = matrix_multiply(matrix_2d, mat_mul);

    println!("Matrix 2D:");
    for row in matrix_2d {
        println!("{:?}", row);
    }

    println!("\nMatrix Mul:");
    for row in mat_mul {
        println!("{:?}", row);
    }

    println!("\nResult:");
    for row in mat_result {
        println!("{:?}", row);
    }
}


// ~~~~~~ cargo run
// Result
Matrix 2D:
[1, 2, 3]
[4, 5, 6]
[7, 8, 9]

Matrix Mul:
[1]
[2]
[3]

Result:
[14]
[32]
[50]

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                             // Your Rust code here
fn matrix_multiply<T>(
    matrix_a: &[Vec<T>],
    matrix_b: &[Vec<T>],
    mut multiply: impl FnMut(&T, &T) -> T,
    mut add: impl FnMut(&T, &T) -> T,
) -> Vec<Vec<T>>
where
    T: Default + Clone,
{
    let rows_a = matrix_a.len();
    let cols_a = matrix_a[0].len();
    let rows_b = matrix_b.len();
    let cols_b = matrix_b[0].len();

    assert_eq!(
        cols_a, rows_b,
        "Matrix dimensions do not match for multiplication!"
    );

    // Initialize the result matrix with default values.
    let mut result = vec![vec![T::default(); cols_b]; rows_a];

    for i in 0..rows_a {
        for j in 0..cols_b {
            for k in 0..cols_a {
                result[i][j] = add(&result[i][j], &multiply(&matrix_a[i][k], &matrix_b[k][j]));
            }
        }
    }

    result
}
  
  

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C언어로 matrix

malloc을 활용하여 동적 활당(dynamic programming)도 가능합니다. 이건...유료 회원에게만...

                             // Your C code here(C matrix)

#include <stdio.h>
#include <string.h>

#define COLS (5)

void init_matrix(int m[][COLS], int rows)
{
    int i, j;
    for (i = 0; i < rows; i++) {
        for (j = 0; j < COLS; j++) {
            m[i][j] = i*j;
        }
    }
}

int main(void)
{
    int matrix[10][COLS];

    init_matrix(matrix, 5);

    // Print the matrix
    for (int i = 0; i < 5; i++) {
        for (int j = 0; j < COLS; j++) {
            printf("%d ", matrix[i][j]);
        }
        printf("\n");
    }

    return 0;
}

// Result

0 0 0 0 0
0 1 2 3 4
0 2 4 6 8
0 3 6 9 12
0 4 8 12 16

matrix 를 0으로 초기화하기

void init_matrix(int m[][COLS], int rows)
{
    int i, j;
    for (i = 0; i < rows; i++) {
        for (j = 0; j < COLS; j++) {
            m[i][j] = 0;
        }
    }
}