Stuck in Javascript (for sharepoint page) array including if statement

Im new to this forum and this is my first Question! I hope you could help me out with it :)

i "stole" some sample code which im editing right now, but i cant figure out where i could state my if because i want to make the chart personal.

  private calculateData(data: Array<Object>, config: ChartConfiguration): Object {
    var values: Array<number> = [];
    var labels: Object = this.getUnique(data, config);
    var dataVal: Array<Array<any>> = this.getValues(data, labels['unique'], config);

    switch (config.act) {
      case 'sum':
        dataVal.forEach((vals, i) => {
          values[i] = 0;
          vals.forEach((val) => {
            values[i] += parseFloat(val);
          });
        });
        break;
        //its about this case where i want to make the label if label = x then parse values 
        case 'point':
            dataVal.forEach((vals, i) => {
            values[i] = 0;
            vals.forEach((val) =>  {
              if (dataVal.indexOf('x') != -1) {
              values[i] = parseFloat(val);  
              }
              });
          }              
          );
        break;
      case 'average':
        dataVal.forEach((vals, i) => {
          values[i] = 0;
          vals.forEach((val) => {
            values[i] += parseFloat(val);
          });
          if (values[i] != 0) {
            values[i] = values[i] / vals.length;
          }
        });
        break;
      case 'count':
        dataVal.forEach((vals) => {
          values.push(vals.length);
        });
        break;
      default:
        values = [100, 250, 90, 300];
        break;
    }
    return { data: values, labels: labels['labels'] };
  }