Multiplying Matrices - Is map and reduce faster?

Benchmark created on April 24, 2023

Setup

// Accepted Answer
function multiplyMatricesA1(m1, m2) {
    var result = [];
    for (var i = 0; i < m1.length; i++) {
        result[i] = [];
        for (var j = 0; j < m2[0].length; j++) {
            var sum = 0;
            for (var k = 0; k < m1[0].length; k++) {
                sum += m1[i][k] * m2[k][j];
            }
            result[i][j] = sum;
        }
    }
    return result;
}

// Fernando Carvajal's answer
function multiplyMatricesA2(A, B) {
    var result = new Array(A.length).fill(0).map(row => new Array(B[0].length).fill(0));

    return result.map((row, i) => {
        return row.map((val, j) => {
            return A[i].reduce((sum, elm, k) => sum + (elm*B[k][j]) ,0)
        })
    })
}

const bigVector = new Array(512).fill(null).map((_, i)=>i);
const bigMatrix = new Array(512).fill(null).map(()=>bigVector.slice(0));

Test runner

multiplyMatricesA1(bigMatrix, bigMatrix);

multiplyMatricesA2(bigMatrix, bigMatrix);

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.

• Revision 1: published on April 24, 2023