/// <summary>
/// Calculates the cashflows for each period according to the chosen model.
/// </summary>
/// <param name="square">Square whose cashflows are to be calculated.
/// <returns>The calculated cashflows for each period according to the chosen model.</returns>
internal static IEnumerable <decimal> CalculateCashflows(this IReadOnlySquare square)
{
for (int i = 0; i < square.Periods - 1; i++)
{
int diagonal = square.Periods + i;
yield return(square.GetDiagonal(diagonal)
.Take(square.Periods - 1 - i)
.Zip(square.GetDiagonal(diagonal - 1), (x, y) => x - y)
.Sum());
}
}
/// <summary>
/// Calculates the reserves for each period according to the chosen model.
/// </summary>
/// <param name="square">Square whose reserves are to be calculated.</param>
/// <returns>The calculated reserves for each period according to the chosen model.</returns>
internal static IEnumerable <decimal> CalculateReserves(this IReadOnlySquare square)
{
return(square.GetColumn(square.Periods - 1)
.Zip(square.GetDiagonal().Reverse(), (x, y) => x - y));
}