public static void SetEntry(ref int _ref, ref int i, ref int j, ref double val, out int ierr)
{
ierr = 0;
try {
IMutableMatrix M = (IMutableMatrix)Infrastructure.GetObject(_ref);
M[i, j] = val;
} catch (Exception e) {
ierr = Infrastructure.ErrorHandler(e);
}
}
/// <summary>
/// extracts the diagonal vector from a matrix.
/// </summary>
static public double[] GetDiagVector(this IMutableMatrix M)
{
int i0 = M.RowPartitioning.i0;
int L = M.RowPartitioning.LocalLength;
double[] diag = new double[L];
for (int i = 0; i < L; i++)
{
diag[i] = M[i + i0, i + i0];
}
return(diag);
}
/// <summary>
/// performs the operation: <paramref name="Acc"/> = <paramref name="Acc"/> + <paramref name="alpha"/>*<paramref name="M"/>
/// </summary>
/// <param name="Acc">
/// Input/Output: the accumulator
/// </param>
/// <param name="alpha">
/// scaling for accumulation
/// </param>
/// <param name="M">
/// Input: the matrix that is accumulated; unchanged on exit.
/// </param>
public static void Acc(this IMutableMatrix Acc, double alpha, IMutableMatrixEx M)
{
if (Acc.NoOfCols != M.NoOfCols)
{
throw new ArgumentException("mismatch in number of columns");
}
if (Acc.NoOfRows != M.NoOfRows)
{
throw new ArgumentException("mismatch in number of rows");
}
if (!Acc.RowPartitioning.EqualsPartition(M.RowPartitioning))
{
throw new ArgumentException("unable to perform Acc - operation: matrices must have equal row partition.");
}
MsrMatrix _M = M as MsrMatrix;
int I = Acc.RowPartitioning.LocalLength;
int i0 = (int)Acc.RowPartitioning.i0;
double[] val = null;
int[] col = null;
int L;
for (int i = 0; i < I; i++)
{
int iRow = i + i0;
L = M.GetRow(iRow, ref col, ref val);
for (int l = 0; l < L; l++)
{
Acc[iRow, col[l]] += alpha * val[l];
}
}
}
