Reduce with Sort

Question

I need to reduce a array, adding the values (I was able to do the code below), now with this reduction I need to do a kind of a SORT to then catch the 3 biggest and the others I’ll make like an if for others I don’t know if you have one lib in nodejs that would facilitate.

1. REDUCE

2. SORT BY THE THREE LARGEST

      var array=[ {
   
           "paymentId" : 1,
           "value" : 290
       },
       {
           "paymentId" : 2,
           "value" : 223
       },
       {
           "paymentId" : 1,
           "value" : 2333
       },
       {
           "paymentId" : 3,
           "value" : 24432
       },
       {
           "paymentId" : 4,
           "value" : 23424
       },
       {
           "paymentId" : 5,
           "value" : 2323
       },
   ]
   var r = array.reduce(function(pv, cv) {
       if ( pv[cv.paymentId] ) {
           pv[cv.paymentId] += cv.value;
       } else {
           pv[cv.paymentId] = cv.value;
       }
       return pv;
   }, {});
   
   console.log(r);
   

EXAMPLE OF 0 RESULT FOR OTHERS

[
    {
        "paymentId" : 3,
        "value" : 24423
    },
    {
        "paymentId" : 4,
        "value" : 23424
    },
    {
        "paymentId" : 1,
        "value" : 2623
    },
    {
        "paymentId" : 0,
        "value" : 2222
    },   
]

Answer 1

If you’re going to turn the array into an object to be able to access the ids from the index, I recommend storing the entire internal object in those indexes, not just its value, since the end result should keep the same format.

var obj = array.reduce((pv, cv) => {
    if (pv[cv.paymentId]) pv[cv.paymentId].value += cv.value
    else pv[cv.paymentId] = {...cv}
    return pv
}, {})

Now to organize it through the method sort, you need to convert it back to an array, as there is no way to organize a structure where values are associated with a key.

var arrayOrdenado = Object.values(obj).sort((a, b) => b.value - a.value)

And the sum of the other results can be obtained with reduce:

var resto = {
    paymentId: 0,
    value: resultado.slice(3).reduce((acc, r) => acc + r.value, 0)
}

Functioning:

var array = [{"paymentId":1,"value":290},{"paymentId":2,"value":223},{"paymentId":1,"value":2333},{"paymentId":3,"value":24432},{"paymentId":4,"value":23424},{"paymentId":5,"value":2323}]

var obj = array.reduce((pv, cv) => {
    if (pv[cv.paymentId]) pv[cv.paymentId].value += cv.value
    else pv[cv.paymentId] = {...cv}
    return pv
}, {})

var arrayOrdenado = Object.values(obj).sort((a, b) => b.value - a.value)

var resultado = arrayOrdenado.slice(0, 3).concat({
    paymentId: 0,
    value: arrayOrdenado.slice(3).reduce((acc, r) => acc + r.value, 0)
})

console.log(resultado)