/// <summary>
/// Reset the row to 0.0 and return true if the row is a current equation
/// </summary>
/// <param name="solver">Solver</param>
/// <param name="variables">List of unknowns/variables</param>
/// <param name="rowIndex">Row number</param>
/// <returns></returns>
protected static bool ZeroNoncurrentRow(SparseLinearSystem <double> solver, VariableSet variables, int rowIndex)
{
if (solver == null)
{
throw new ArgumentNullException(nameof(solver));
}
if (variables == null)
{
throw new ArgumentNullException(nameof(variables));
}
bool currents = false;
for (int n = 0; n < variables.Count; n++)
{
var node = variables[n];
MatrixElement <double> x = solver.FindMatrixElement(rowIndex, node.Index);
if (x != null && !x.Value.Equals(0.0))
{
if (node.UnknownType == VariableType.Current)
{
currents = true;
}
else
{
x.Value = 0.0;
}
}
}
return(currents);
}
/// <summary>
/// Apply an additional conductance to the diagonal elements of a matrix that is typically constructed using Modified Nodal Analysis (MNA).
/// </summary>
/// <param name="solver">The solver.</param>
/// <param name="gmin">The conductance to be added.</param>
/// <exception cref="ArgumentNullException">solver</exception>
public static void ApplyDiagonalGmin(this SparseLinearSystem <double> solver, double gmin)
{
solver.ThrowIfNull(nameof(solver));
// Skip if not necessary
if (gmin <= 0.0)
{
return;
}
// Add to the diagonal
for (var i = 1; i <= solver.Order; i++)
{
var diagonal = solver.ReorderedDiagonal(i);
if (diagonal != null)
{
diagonal.Value += gmin;
}
}
}
/// <summary>
/// Apply a gmin to the diagonal elements
/// </summary>
/// <param name="solver">Solver</param>
/// <param name="gmin">Conductance</param>
public static void ApplyDiagonalGmin(this SparseLinearSystem <double> solver, double gmin)
{
if (solver == null)
{
throw new ArgumentNullException(nameof(solver));
}
// Skip if not necessary
if (gmin <= 0.0)
{
return;
}
// Add to the diagonal
for (int i = 1; i <= solver.Order; i++)
{
var diagonal = solver.ReorderedDiagonal(i);
if (diagonal != null)
{
diagonal.Value += gmin;
}
}
}
