/// <summary>
/// See <see cref="ITriangulation.SolveLinearSystem(Vector, Vector)"/>.
/// </summary>
/// <exception cref="LapackException">Thrown if the call to LAPACK fails due to invalid arguments.</exception>
public void SolveLinearSystem(Vector rhs, Vector solution)
{
CheckOverwritten();
Preconditions.CheckSystemSolutionDimensions(Order, rhs.Length);
Preconditions.CheckMultiplicationDimensions(Order, solution.Length);
// Back & forward substitution using LAPACK
solution.CopyFrom(rhs);
int numRhs = 1; // rhs is a n x nRhs matrix, stored in b
int leadingDimB = Order; // column major ordering: leading dimension of b is n
LapackLinearEquations.Dpotrs(StoredTriangle.Upper, Order, numRhs, data, 0, Order, solution.RawData, 0,
leadingDimB);
}
/// <summary>
/// Solves a series of linear systems L * L^T * x = b (or L * D * L^T * x = b), where L is the lower triangular factor
/// (and D the diagonal factor) of the Cholesky factorization: A = L * L^T (or A = L * D * L^T).
/// </summary>
/// <param name="rhsVectors">
/// A matrix whose columns are the right hand side vectors b of the linear systems. Constraints:
/// <paramref name="rhsVectors"/>.<see cref="IIndexable2D.NumRows"/> == this.<see cref="Order"/>.
/// </param>
/// <exception cref="NonMatchingDimensionsException">
/// Thrown if <paramref name="rhsVectors"/> violates the described constraints.
/// </exception>
/// <exception cref="AccessViolationException">
/// Thrown if the unmanaged memory that holds the factorization data has been released.
/// </exception>
/// <exception cref="SuiteSparseException">Thrown if the call to SuiteSparse library fails.</exception>
public Matrix SolveLinearSystems(Matrix rhs)
{
CheckOverwritten();
Preconditions.CheckSystemSolutionDimensions(Order, rhs.NumRows);
//Preconditions.CheckMultiplicationDimensions(Order, solution.NumColumns);
// Back & forward substitution using LAPACK
Matrix solution = rhs.Copy();
int numRhs = rhs.NumColumns; // rhs is a n x nRhs matrix, stored in b
int leadingDimB = Order; // column major ordering: leading dimension of b is n
LapackLinearEquations.Dpotrs(StoredTriangle.Upper, Order, numRhs, data, 0, Order, solution.RawData, 0,
leadingDimB);
return(solution);
}
