Javascript - Calculation of school grades with object use, is it possible?

Question

My intention is to make the famous algorithm of school grades to calculate the average student, which is usually done with arrays, but I want to know if it is also possible with use of objects, my attempt was this, but I’m getting Undefined as a result:

var alunos = []
var media = 0;
var soma = 0;

for (let i = 0; i <= 3; i++) {
    const aluno = {
        name: prompt('NOME: '),
        nota1: Number(prompt('NOTA 1:')),
        nota2: Number(prompt('NOTA 2:')),
        nota3: Number(prompt('NOTA 3:')),
        nota4: Number(prompt('NOTA 4:'))

    }
    alunos.push(aluno);
    soma += aluno.nota1.nota2.nota3.nota4
    media = soma / alunos.length;
    console.log(media);

    // zerando os dados para realizar o cálculo dos próximos alunos
    media = 0;
    soma = 0;
}

If the question is not clear, the objective of the algorithm is to receive the student’s name, his 4 grades and after that calculate his average.

Answer 1

You can use a function reduce allied to the destruction of the object:

const alunos = []

const calcular = ({ nota1, nota2, nota3, nota4 }) => [nota1, nota2, nota3, nota4].reduce((total, nota) => total + nota) / 4;

for (let i = 0; i <= 3; i++) {
  const aluno = {
    nome: prompt('NOME: '),
    nota1: Number(prompt('NOTA 1:')),
    nota2: Number(prompt('NOTA 2:')),
    nota3: Number(prompt('NOTA 3:')),
    nota4: Number(prompt('NOTA 4:')),
  };

  alunos.push(aluno);
  console.log(`${aluno.nome} ${calcular(aluno)}`);
}

---

reduce

The method reduce() performs a function reducer (provided by you) for each member of the array, resulting in a single return value.

Example:

const array1 = [1, 2, 3, 4];
const reducer = (accumulator, currentValue) => accumulator + currentValue;

// 1 + 2 + 3 + 4
console.log(array1.reduce(reducer));
// expected output: 10

// 5 + 1 + 2 + 3 + 4
console.log(array1.reduce(reducer, 5));
// expected output: 15

---

Assignment via structuring (destructuring assignment).

The syntax of assignment via structuring (destructuring assignment) is a Javascript expression that allows you to extract data from arrays or objects in different variables.

var a, b, rest;
[a, b] = [1, 2];
console.log(a); // 1
console.log(b); // 2

[a, b, ...rest] = [1, 2, 3, 4, 5];
console.log(a); // 1
console.log(b); // 2
console.log(rest); // [3, 4, 5]

({a, b} = {a:1, b:2});
console.log(a); // 1
console.log(b); // 2