CSMSL.Tolerance.CalculatePrecursorMassError C# (CSharp) Method

        public static Tolerance CalculatePrecursorMassError(double theoreticalMass, double observedMass, out int nominalMassOffset, out double adjustedObservedMass, double difference = Constants.C13C12Difference,
            ToleranceUnit type = ToleranceUnit.PPM)
        {
            double massError = observedMass - theoreticalMass;
            nominalMassOffset = (int) Math.Round(massError/difference);
            double massOffset = nominalMassOffset*difference;
            adjustedObservedMass = observedMass - massOffset;
            return new Tolerance(type, adjustedObservedMass, theoreticalMass);
        }