Highcharts - Setting new minimum maximum values (extremes) for Y-axis

I use the following code to define min-max values of a chart:

    var min1 = Math.min.apply(Math, data1);  
    var min2 = Math.min.apply(Math, data2);  
    var min3 = Math.min.apply(Math, data3);  
    var min = Math.min(min1, min2, min3);
   
    var max1 = Math.max.apply(Math, data1);  
    var max2 = Math.max.apply(Math, data2);  
    var max3 = Math.max.apply(Math, data3);  
    var max = Math.max(max1, max2, max3);                       
    .
    .
    .



    yAxis: {
                min: min,
                max: max,


However, after modifications made to the chart like adding/removing points, these values need to be updated. Here is how you can do it:

   var max = chart1.yAxis[0].getExtremes().dataMax;
   var min = chart1.yAxis[0].getExtremes().dataMin;
   chart1.yAxis[0].setExtremes(min, max);
   chart1.redraw();