How to use the @swimlane/ngx-charts.getUniqueXDomainValues function in @swimlane/ngx-charts

getXDomain(): any[] {
    let values = getUniqueXDomainValues(this.results);

    this.scaleType = getScaleType(values);
    let domain = [];

    if (this.scaleType === 'linear') {
      values = values.map(v => Number(v));
    }

    let min;
    let max;
    if (this.scaleType === 'time' || this.scaleType === 'linear') {
      min = this.xScaleMin
        ? this.xScaleMin
        : Math.min(...values);

      max = this.xScaleMax