/// <summary>
/// Reads data from underlying a and b series
/// then subtracts a - b
/// </summary>
protected override void ReadCore(DateTime t1, DateTime t2)
{
a.Read(t1, t2);
b.Read(t1, t2);
SetUnits(a, b);
Series s = Math.Subtract(a, b);
this.Add(s);
}
private Series ApplyOperator(Series s1, Series s2, MathOperation op)
{
Series s = null;
if (op == MathOperation.Subtract)
{
s = Math.Subtract(s1, s2);
}
else if (op == MathOperation.Add)
{
s = Math.Add(s1, s2);
}
return(s);
}
