How to multiply two matrices?

Question

JavaScript

There is a function for obtaining data from inputs and a function for obtaining a product from multiplication. That's it with the multiplication function I got confused. Tell me in 1 is the definition of matrices correct at all? why does it write that they are not protected when calling variables in the console? for example variable A or rows? Is the variable C or t the product of two matrices? and how, for example, to display the product in the console?
html here

function readMatrixFromDom(aClassName) {
      var result = [];
      var rows = $('.' + aClassName).find('tr');
      for (var i = 0; i < rows.length; i++) {
        result.push([]);
        var cells = $(rows[i]).find('td > input');
        for (var j = 0; j < cells.length; j++) {
          result[i].push(+$(cells[j]).val());
        }
      }
      return result;
    }

  function MultiplyMatrix(A,B){

    var A = readMatrixFromDom('matrix_a');
    var B = readMatrixFromDom('matrix_b');
    var rowsA = A.length, colsA = A[0].length,
        rowsB = B.length, colsB = B[0].length,
        C = [];
    if (colsA != rowsB) return false;
    for (var i = 0; i < rowsA; i++) C[i] = [];
    for (var k = 0; k < colsB; k++)
    { for (var i = 0; i < rowsA; i++)
    { var t = 0;
     for (var j = 0; j < rowsB; j++) t += A[i][j]*B[j][k];
     C[i][k] = t;
    }
    }
    return C;
  }

Answer 1

If I were you, I would not implement the MultiplyMatrix function, unless for some educational purposes, but would use numericjs