/// <returns>true when exact 'value' is anywhere on the diagonal.</returns>
public static bool HasValueOnDiagonal(DotNetMatrix.GeneralMatrix m, double value)
{
for (int i = 0; i < Math.Min(m.RowDimension, m.ColumnDimension); i++)
{
if (m.GetElement(i, i) == value)
{
return(true);
}
}
return(false);
}
public static String ToString(DotNetMatrix.GeneralMatrix m)
{
System.Text.StringBuilder result = new System.Text.StringBuilder();
for (int i = 0; i < m.RowDimension; i++)
{
for (int j = 0; j < m.ColumnDimension; j++)
{
result.Append(m.GetElement(i, j));
result.Append(" ");
}
result.Append("\n");
}
return(result.ToString());
}
public static bool IsDiagonal(DotNetMatrix.GeneralMatrix m)
{
const double EPS = 1e-6;
for (int i = 0; i < m.RowDimension; i++)
{
for (int j = 0; j < m.ColumnDimension; j++)
{
if ((i != j) && (Math.Abs(m.GetElement(i, j)) > EPS))
{
return(false);
}
}
}
return(true);
}
/// <summary>
/// Returns true when the matrix is diagonal and has only exact 0, +1 and/or -1 entries on the diagonal.
/// </summary>
/// <param name="m">the (square) matrix</param>
/// <returns></returns>
public static bool IsSimpleDiagonal(DotNetMatrix.GeneralMatrix m)
{
for (int i = 0; i < m.RowDimension; i++)
{
for (int j = 0; j < m.ColumnDimension; j++)
{
double v = m.GetElement(i, j);
if ((i != j) && (v != 0.0))
{
return(false);
}
else if (i == j)
{
if (!((v == 0.0) || (v == 1.0) || (v == -1.0)))
{
return(false);
}
}
}
}
return(true);
}