JSFiddle - React, Tailwind, and code Playground

by andreortigao

HTML

<span id="result"></span>

JavaScript

var matrix = [[1,2,3], [4,5,6], [7,8,9]];

var resultVector = MatrixFun(matrix);

print(resultVector);

function getCornersPositions(matrix){
    var yAxisLenght = matrix.length -1;
    var xAxisLength = matrix[0].length -1;
    
    return [ 
        [0,0], 
        [0, xAxisLength], 
        [yAxisLenght, 0], 
        [xAxisLength, yAxisLenght] 
    ];
}

function getMiddleVectorPosition(matrix){
    return Math.ceil( matrix.length / 2) -1;
}

function MatrixFun(matrix){
    var c = getCornersPositions(matrix);
    
    var sumOfCorners = matrix[ c[0][0] ][ c[0][1] ] 
                     + matrix[ c[1][0] ][ c[1][1] ]
                     + matrix[ c[2][0] ][ c[2][1] ]
                     + matrix[ c[3][0] ][ c[3][1] ];
    
    console.log(sumOfCorners);
    
    var middleVector = getMiddleVectorPosition(matrix);
    
    var resultVector = [];
    for(var row in matrix)
        resultVector.push( sumOfCorners * matrix[row][middleVector]);
    
    return resultVector;
}

function print(x){ $("#result").append(x.toString()); }