protected override MsrMatrix ComputeMatrix()
{
MsrMatrix Approx = m_Approx.AssemblyMatrix;
MsrMatrix ApproxInv = new MsrMatrix(Approx.RowPartitioning, Approx.ColPartition);
switch (m_SolverConf.PredictorApproximation)
{
case PredictorApproximations.Identity:
case PredictorApproximations.Identity_IP1:
case PredictorApproximations.Diagonal:
int i0 = Approx.RowPartitioning.i0;
int LocalLength = Approx.RowPartitioning.LocalLength;
for (int row = 0; row < LocalLength; row++)
{
double Approx_ii = Approx[row + i0, row + i0];
ApproxInv[row + i0, row + i0] = 1.0 / Approx_ii;
}
break;
case PredictorApproximations.BlockDiagonal:
BlockDiagonalMatrix ApproxBlock = new BlockDiagonalMatrix(Approx, Approx.RowPartitioning.LocalLength / m_LocalNoOfCells, Approx.ColPartition.LocalLength / m_LocalNoOfCells);
BlockDiagonalMatrix ApproxBlockInv = ApproxBlock.Invert();
ApproxInv.Acc(1.0, ApproxBlockInv);
break;
default:
throw new ArgumentException();
}
return(ApproxInv);
}
public void Init(MultigridOperator op)
{
BlockMsrMatrix M = op.OperatorMatrix;
var MgMap = op.Mapping;
this.m_MultigridOp = op;
if (!M.RowPartitioning.Equals(MgMap.Partitioning))
{
throw new ArgumentException("Row partitioning mismatch.");
}
if (!M.ColPartition.Equals(MgMap.Partitioning))
{
throw new ArgumentException("Column partitioning mismatch.");
}
Mtx = M;
int L = M.RowPartitioning.LocalLength;
/*
* diag = new double[L];
* int i0 = Mtx.RowPartitioning.i0;
*
* for(int i = 0; i < L; i++) {
* diag[i] = Mtx[i0 + i, i0 + i];
* }
*/
if (op.Mapping.MaximalLength != op.Mapping.MinimalLength)
{
// 'BlockDiagonalMatrix' should be completely replaced by 'BlockMsrMatrix'
throw new NotImplementedException("todo - Block Jacobi for variable block Sizes");
}
int Nblk = op.Mapping.MaximalLength;
Diag = new BlockDiagonalMatrix(M.ToMsrMatrix(), Nblk, Nblk);
invDiag = Diag.Invert();
invDiag.CheckForNanOrInfM();
}