Change a variable's value through ES6 Interpolation

Question

Consider this code

           switch (rackID) {
                case 1:
                    rack_data.rack1.temp = [temp1, temp2, temp3, temp4, temp5, temp6];
                    break;
                case 2:
                    rack_data.rack2.temp = [temp1, temp2, temp3, temp4, temp5, temp6];
                    break;
                case 3:
                    rack_data.rack3.temp = [temp1, temp2, temp3, temp4, temp5, temp6];
                    break;
                 

Notice how this code is repetitive whereas using this code would be useful rack_data.rack${rackID}.temp = [temp1, temp2, temp3, temp4, temp5, temp6] could be better, but this isn't allowed.

I know eval exists, but everyone says that it poses security issues so I'm trying to look for a alternative.