Tengo esta matriz de objetos:
const data = [ { position: 1, name: "a", score: 9000 }, { position: 2, name: "b", score: 8000 }, { position: 3, name: "c", score: 6000 }, { position: 3, name: "c", score: 6000 }, { position: 4, name: "d", score: 6000 }, { position: 5, name: "e", score: 6000 }, { position: 6, name: "f", score: 6000 }, { position: 7, name: "g", score: 4000 }, { position: 8, name: "h", score: 3000 }, { position: 9, name: "i", score: 2500 }, { position: 10, name: "j", score: 2500 }, { position: 11, name: "k", score: 1000 }, { position: 12, name: "l", score: 1000 }, ];Estoy tratando de iterarlo usando solo JavaScript simple para obtener el siguiente resultado:
const data = [ { position: "1", name: "a", score: 9000 }, { position: "2", name: "b", score: 8000 }, { position: "3-6", name: "c", score: 6000 }, { position: "3-6", name: "c", score: 6000 }, { position: "3-6", name: "d", score: 6000 }, { position: "3-6", name: "e", score: 6000 }, { position: "3-6", name: "f", score: 6000 }, { position: "7", name: "g", score: 4000 }, { position: "8", name: "h", score: 3000 }, { position: "9-10", name: "i", score: 2500 }, { position: "9-10", name: "j", score: 2500 }, { position: "11-12", name: "k", score: 1000 }, { position: "11-12", name: "l", score: 1000 }, ];He intentado muchos enfoques diferentes pero nada funciona, desafortunadamente. ¿Algún consejo sobre cómo lograr esto? Gracias por adelantado.
Esto es probablemente lo más cercano que tengo:
function placement() { let repeat=0; for (let i = 0; i < data.length; i++) { let counter = 0; for (let j = 0; j < data.length; j++) { if (data[i].score == data[j].score) { if(data[i].position==data[j].position){ repeat++; } counter++; } } if (counter > 1) { let k; let start=data[i].position; for (k = i; k < i + counter-1; k++) { data[k].position = start + "-" + data[i + counter-1].position; } i=k; } } }Suponiendo que los elementos de los data están ordenados por puntuación, es decir, los rangos están comprimidos en una instancia por valor, puede hacer lo siguiente:
Array#reduce mientras actualiza un Map que tiene la score como clave y sus positions inicial y final como valor.Array#map , itere sobre la matriz nuevamente y para cada elemento, establezca la posición en los valores guardados en el Mapa: const data = [ { position: 1, name: "a", score: 9000 }, { position: 2, name: "b", score: 8000 }, { position: 3, name: "c", score: 6000 }, { position: 3, name: "c", score: 6000 }, { position: 4, name: "d", score: 6000 }, { position: 5, name: "e", score: 6000 }, { position: 6, name: "f", score: 6000 }, { position: 7, name: "g", score: 4000 }, { position: 8, name: "h", score: 3000 }, { position: 9, name: "i", score: 2500 }, { position: 10, name: "j", score: 2500 }, { position: 11, name: "k", score: 1000 }, { position: 12, name: "l", score: 1000 }, ]; const scoreMap = data.reduce((map, { position, score }) => { const { start } = map.get(score) || {}; if(start) (map.get(score)).end = position; else map.set(score, { start: position }); return map; }, new Map); const res = data.map(e => { const { start, end } = scoreMap.get(e.score); return { ...e, position: end ? `${start}-${end}` : `${start}` }; }); console.log(res);Puede agrupar por score primero y luego agregar la posición para cada grupo.
const data = [{ position: 1, name: "a", score: 9000 }, { position: 2, name: "b", score: 8000 }, { position: 3, name: "c", score: 6000 }, { position: 3, name: "c", score: 6000 }, { position: 4, name: "d", score: 6000 }, { position: 5, name: "e", score: 6000 }, { position: 6, name: "f", score: 6000 }, { position: 7, name: "g", score: 4000 }, { position: 8, name: "h", score: 3000 }, { position: 9, name: "i", score: 2500 }, { position: 10, name: "j", score: 2500 }, { position: 11, name: "k", score: 1000 }, { position: 12, name: "l", score: 1000 }], result = data .reduce((r, o, i, a) => { if (!i || a[i - 1].score !== o.score) r.push([]); r[r.length - 1].push(o); return r; }, []) .flatMap(a => a.map((o, i, b) => b.length === 1 ? o : { ...o, position: `${b[0].position}-${b[b.length - 1].position}` } )); console.log(result); .as-console-wrapper { max-height: 100% !important; top: 0; }