// Parses MCF wavefunction.
internal static SparseMultiCFWavefunction <SpinOrbital> ToSparseMultiCFWavefunction(List <List <string> > superposition)
{
var outputState = new SparseMultiCFWavefunction <SpinOrbital>();
// Todo: modify broombridge to have explicit reference state.
foreach (var element in superposition)
{
// First item is the amplitude.
double amplitude = double.Parse(element.First().ToString(), System.Globalization.CultureInfo.InvariantCulture);
// Second to Second-last are fermion operators.
IEnumerable <LadderOperator <SpinOrbital> > operators = element
.Take(element.Count() - 1)
.Skip(1)
.Select(o => V0_1.ParsePolishNotation(o.ToString()));
var ladderSequence = new LadderSequence <SpinOrbital>(operators);
// Sort operators to index order.
IEnumerable <IndexOrderedSequence <SpinOrbital> > sortedOperators = ladderSequence.ToIndexOrder();
// Only select the shortest term with no repeated indices.
IndexOrderedSequence <SpinOrbital> sortedOperator = sortedOperators.ToList().OrderBy(o => o.UniqueIndices()).First();
outputState.Set(sortedOperator, new Complex(amplitude, 0.0));
}
return(outputState);
}
/// <summary>
/// Translate initial state specified by a superposition of <see cref="FermionTerm"/> acting on
/// the vacuum state to a format consumable by Q#
/// </summary>
/// /// <param name="term">List of sequences of creation operations acting on vacuum state and their coefficients.</param>
/// <returns>Q# description of initial state</returns>
public static QArray <JordanWignerInputState> InitialStateSparseMultiConfigural(
SparseMultiCFWavefunction <int> wavefunction)
{
return(new QArray <JordanWignerInputState>(
wavefunction.Excitations.Select(o => InitialStatePrep(o.Value, o.Key, checkAnnihilation: true))
// Todo add reference wavefunction when that functionality is implemented.
));
}
