public override ExplicitMatrix AsExplicitMatrix()
    {
        if (m_ExplicitMatrix == null || m_ExplicitMatrix.GetM() != m_Size || m_ExplicitMatrix.GetN() != m_Size)
        {
            m_ExplicitMatrix = new ExplicitMatrix(m_Size, m_Size);
        }
        else
        {
            m_ExplicitMatrix.Clear();
        }
        ExplicitMatrix J_Explicit = m_J.AsExplicitMatrix();

        int jn = J_Explicit.GetN();

        for (int i = 0; i < m_Size; ++i)
        {
            for (int j = i; j < m_Size; ++j)
            {
                double x = 0;
                for (int k = 0; k < jn; ++k)
                {
                    double y = J_Explicit.GetValue(i, k);
                    double z = m_W[k] * J_Explicit.GetValue(j, k);
                    x += y * z;
                }
                m_ExplicitMatrix.SetValue(i, j, x);
                m_ExplicitMatrix.SetValue(j, i, x);
            }
        }
        return(m_ExplicitMatrix);
    }
    public override ExplicitMatrix AsExplicitMatrix()
    {
        if (m_ExplicitMatrix == null || m_ExplicitMatrix.GetM() != m_m || m_ExplicitMatrix.GetN() != m_n)
        {
            m_ExplicitMatrix = new ExplicitMatrix(m_m, m_n);
        }
        else
        {
            m_ExplicitMatrix.Clear();
        }
        MatrixBlock curBlock;

        for (int k = 0; k < m_MatrixBlocks.Count; ++k)
        {
            curBlock = m_MatrixBlocks[k];
            int starti  = curBlock.i;
            int startj  = curBlock.j;
            int iLength = starti + curBlock.iLength;
            int jLength = startj + curBlock.jLength;
            for (int i = starti; i < iLength; ++i)
            {
                for (int j = startj; j < jLength; ++j)
                {
                    m_ExplicitMatrix.SetValue(i, j, curBlock.data[(i - starti) * (jLength - startj) + (j - startj)]);
                }
            }
        }
        return(m_ExplicitMatrix);
    }