added comments

app/src/main/java/com/elearning/probabilityandstatisticsanalyserandeducator/calculationfunction/DesStatCalculation.java

@@ -22,6 +22,7 @@ public class DesStatCalculation {
     //median calculation
     double mid;
     public ArrayList<Object> Median(String[] a ) {
+        //create array list for store the values for parsing values to fragment
         ArrayList<Object> list = new ArrayList<>();
         double[] invalue = new double[a.length];
       //  System.out.println("Invaue in median:"+Arrays.toString(invalue));