así que esta es mi matriz:
0: {universityYear: 'Anul universitar 2022-2023', name: 'Pimpulsul'} 1: {universityYear: 'Anul universitar 2021-2022', name: 'Evrikaul'} 2: {universityYear: 'Anul universitar 2021-2022', name: 'Po'}y quiero obtener:
0: {universityYear: 'Anul universitar 2022-2023', name: ['Pimpulsul'] } 1: {universityYear: 'Anul universitar 2021-2022', name: ['Evrikaul', 'Po'] }Puedes usar la reduce :
let arr = [ {universityYear: 'Anul universitar 2022-2023', name: 'Pimpulsul'}, {universityYear: 'Anul universitar 2021-2022', name: 'Evrikaul'}, {universityYear: 'Anul universitar 2021-2022', name: 'Po'} ]; let newArr = arr.reduce((out, cv, ci, re) => { let targetIndex = out.findIndex(item => item.universityYear == cv.universityYear); if(targetIndex > -1) out[targetIndex].name.push(cv.name); else out.push({...cv, name: [cv.name]}) return out; }, []); console.log(newArr)