public static Adduct CalcProductCharge(TypedMass productPrecursorMass,
int?productZ,
Adduct precursorCharge,
IList <IonType> acceptedIonTypes,
IonTable <TypedMass> productMasses,
IList <IList <ExplicitLoss> > potentialLosses,
double productMz,
double tolerance,
MassType massType,
MassShiftType massShiftType,
out IonType?ionType,
out int?ordinal,
out TransitionLosses losses,
out int massShift)
{
// Get length of fragment ion mass array
int len = productMasses.GetLength(1);
// Check all possible ion types and offsets
double?minDelta = null;
double?minFragmentMass = null, maxFragmentMass = null, maxLoss = null;
if (massShiftType == MassShiftType.none)
{
if (!productZ.HasValue)
{
minFragmentMass = productMz - tolerance;
}
else
{
minFragmentMass = SequenceMassCalc.GetMH(productMz - tolerance, productZ.Value);
maxFragmentMass = SequenceMassCalc.GetMH(productMz + tolerance, productZ.Value);
}
}
var bestCharge = Adduct.EMPTY;
IonType? bestIonType = null;
int? bestOrdinal = null;
TransitionLosses bestLosses = null;
int bestMassShift = 0;
// Check to see if it is the precursor
foreach (var lossesTrial in TransitionGroup.CalcTransitionLosses(IonType.precursor, 0, massType, potentialLosses))
{
var productMass = productPrecursorMass;
if (lossesTrial != null)
{
productMass -= lossesTrial.Mass;
maxLoss = Math.Max(maxLoss ?? 0, lossesTrial.Mass);
}
int potentialMassShift;
int nearestCharge;
var charge = CalcProductCharge(productMass, productZ, productMz, tolerance, false, precursorCharge,
massShiftType, out potentialMassShift, out nearestCharge);
if (Equals(charge, precursorCharge))
{
double potentialMz = SequenceMassCalc.GetMZ(productMass, charge) + potentialMassShift;
double delta = Math.Abs(productMz - potentialMz);
if (CompareIonMatch(delta, lossesTrial, potentialMassShift, minDelta, bestLosses, bestMassShift) < 0)
{
bestCharge = charge;
bestIonType = IonType.precursor;
bestOrdinal = len + 1;
bestLosses = lossesTrial;
bestMassShift = potentialMassShift;
minDelta = delta;
}
}
}
if (maxLoss.HasValue)
{
maxFragmentMass += maxLoss.Value;
}
var categoryLast = -1;
foreach (var typeAccepted in GetIonTypes(acceptedIonTypes))
{
var type = typeAccepted.IonType;
var category = typeAccepted.IonCategory;
// Types have priorities. If changing type category, and there is already a
// suitable answer stop looking.
if (category != categoryLast && minDelta.HasValue && MatchMz(minDelta.Value, tolerance))
{
break;
}
categoryLast = category;
// The peptide length is 1 longer than the mass array
for (int ord = len; ord > 0; ord--)
{
int offset = Transition.OrdinalToOffset(type, ord, len + 1);
var productMassBase = productMasses[type, offset];
// Until below the maximum fragment mass no possible matches
if (maxFragmentMass.HasValue && productMassBase > maxFragmentMass.Value)
{
continue;
}
// Once below the minimum fragment mass no more possible matches, so stop
if (minFragmentMass.HasValue && productMassBase < minFragmentMass.Value)
{
break;
}
foreach (var lossesTrial in TransitionGroup.CalcTransitionLosses(type, offset, massType, potentialLosses))
{
// Look for the closest match.
var productMass = productMassBase;
if (lossesTrial != null)
{
productMass -= lossesTrial.Mass;
}
int potentialMassShift;
int nearestCharge;
var chargeFound = CalcProductCharge(productMass, productZ, productMz, tolerance, false, precursorCharge,
massShiftType, out potentialMassShift, out nearestCharge);
if (!chargeFound.IsEmpty)
{
var charge = chargeFound;
double potentialMz = SequenceMassCalc.GetMZ(productMass, charge) + potentialMassShift;
double delta = Math.Abs(productMz - potentialMz);
if (CompareIonMatch(delta, lossesTrial, potentialMassShift, minDelta, bestLosses, bestMassShift) < 0)
{
bestCharge = charge;
bestIonType = type;
bestOrdinal = ord;
bestLosses = lossesTrial;
bestMassShift = potentialMassShift;
minDelta = delta;
}
}
}
}
}
ionType = bestIonType;
ordinal = bestOrdinal;
losses = bestLosses;
massShift = bestMassShift;
return(bestCharge);
}
public static Adduct CalcProductCharge(TypedMass productPrecursorMass,
Adduct precursorCharge,
IList <IonType> acceptedIonTypes,
IonTable <TypedMass> productMasses,
IList <IList <ExplicitLoss> > potentialLosses,
double productMz,
double tolerance,
MassType massType,
MassShiftType massShiftType,
out IonType?ionType,
out int?ordinal,
out TransitionLosses losses,
out int massShift)
{
// Get length of fragment ion mass array
int len = productMasses.GetLength(1);
// Check all possible ion types and offsets
double? minDelta = null;
var bestCharge = Adduct.EMPTY;
IonType? bestIonType = null;
int? bestOrdinal = null;
TransitionLosses bestLosses = null;
int bestMassShift = 0;
// Check to see if it is the precursor
foreach (var lossesTrial in TransitionGroup.CalcTransitionLosses(IonType.precursor, 0, massType, potentialLosses))
{
var productMass = productPrecursorMass - (lossesTrial != null ? lossesTrial.Mass : 0);
int potentialMassShift;
int nearestCharge;
var charge = CalcProductCharge(productMass, productMz, tolerance, false, precursorCharge,
massShiftType, out potentialMassShift, out nearestCharge);
if (Equals(charge, precursorCharge))
{
double potentialMz = SequenceMassCalc.GetMZ(productMass, charge) + potentialMassShift;
double delta = Math.Abs(productMz - potentialMz);
if (CompareIonMatch(delta, lossesTrial, potentialMassShift, minDelta, bestLosses, bestMassShift) < 0)
{
bestCharge = charge;
bestIonType = IonType.precursor;
bestOrdinal = len + 1;
bestLosses = lossesTrial;
bestMassShift = potentialMassShift;
minDelta = delta;
}
}
}
var categoryLast = -1;
foreach (var typeAccepted in GetIonTypes(acceptedIonTypes))
{
var type = typeAccepted.IonType;
var category = typeAccepted.IonCategory;
// Types have priorities. If changing type category, and there is already a
// suitable answer stop looking.
if (category != categoryLast && minDelta.HasValue && MatchMz(minDelta.Value, tolerance))
{
break;
}
categoryLast = category;
for (int offset = 0; offset < len; offset++)
{
foreach (var lossesTrial in TransitionGroup.CalcTransitionLosses(type, offset, massType, potentialLosses))
{
// Look for the closest match.
var productMass = productMasses[type, offset];
if (lossesTrial != null)
{
productMass -= lossesTrial.Mass;
}
int potentialMassShift;
int nearestCharge;
var chargeFound = CalcProductCharge(productMass, productMz, tolerance, false, precursorCharge,
massShiftType, out potentialMassShift, out nearestCharge);
if (!chargeFound.IsEmpty)
{
var charge = chargeFound;
double potentialMz = SequenceMassCalc.GetMZ(productMass, charge) + potentialMassShift;
double delta = Math.Abs(productMz - potentialMz);
if (CompareIonMatch(delta, lossesTrial, potentialMassShift, minDelta, bestLosses, bestMassShift) < 0)
{
bestCharge = charge;
bestIonType = type;
// The peptide length is 1 longer than the mass array
bestOrdinal = Transition.OffsetToOrdinal(type, offset, len + 1);
bestLosses = lossesTrial;
bestMassShift = potentialMassShift;
minDelta = delta;
}
}
}
}
}
ionType = bestIonType;
ordinal = bestOrdinal;
losses = bestLosses;
massShift = bestMassShift;
return(bestCharge);
}