How to combine an array in javascript

Question

Hello I want to merge a array based on the unique item in the array.

The object that I have

totalCells = []

In this totalCells arr

Answer 1

What about something like this :

totalCells.reduce(function(a, b) {
  if(!a[b.lineNumber]){
    a[b.lineNumber] = {
      lineNumber: b.lineNumber,
      cells: [b.cellwidth]
    }
  }
  else{
    a[b.lineNumber].cells.push(b.cellwidth);
  }
  return a;
}, []);

Hope this helps!