Beispiel #1
0
Real InfHex::quality (const ElemQuality q) const
{
  switch (q)
    {

      /**
       * Compue the min/max diagonal ratio.
       * Source: CUBIT User's Manual.
       *
       * For infinite elements, we just only compute
       * the diagonal in the face...
       * Don't know whether this makes sense,
       * but should be a feasible way.
       */
    case DIAGONAL:
      {
	// Diagonal between node 0 and node 2
	const Real d02 = this->length(0,2);

	// Diagonal between node 1 and node 3
	const Real d13 = this->length(1,3);

	// Find the biggest and smallest diagonals
	const Real min = std::min(d02, d13);
	const Real max = std::max(d02, d13);

	libmesh_assert_not_equal_to (max, 0.0);

	return min / max;

	break;
      }

      /**
       * Minimum ratio of lengths derived from opposite edges.
       * Source: CUBIT User's Manual.
       *
       * For IFEMs, do this only for the base face...
       * Does this make sense?
       */
    case TAPER:
      {

	/**
	 * Compute the side lengths.
	 */
	const Real d01 = this->length(0,1);
	const Real d12 = this->length(1,2);
	const Real d23 = this->length(2,3);
	const Real d03 = this->length(0,3);

	std::vector<Real> edge_ratios(2);

	// Bottom
	edge_ratios[8] = std::min(d01, d23) / std::max(d01, d23);
	edge_ratios[9] = std::min(d03, d12) / std::max(d03, d12);

	return *(std::min_element(edge_ratios.begin(), edge_ratios.end())) ;

	break;
      }


      /**
       * Minimum edge length divided by max diagonal length.
       * Source: CUBIT User's Manual.
       *
       * And again, we mess around a bit, for the IFEMs...
       * Do this only for the base.
       */
    case STRETCH:
      {
	/**
	 * Should this be a sqrt2, when we do this for the base only?
	 */
	const Real sqrt3 = 1.73205080756888;

	/**
	 * Compute the maximum diagonal in the base.
	 */
	const Real d02 = this->length(0,2);
	const Real d13 = this->length(1,3);
	const Real max_diag = std::max(d02, d13);

	libmesh_assert_not_equal_to ( max_diag, 0.0 );

	/**
	 * Compute the minimum edge length in the base.
	 */
	std::vector<Real> edges(4);
	edges[0]  = this->length(0,1);
	edges[1]  = this->length(1,2);
	edges[2]  = this->length(2,3);
	edges[3]  = this->length(0,3);

	const Real min_edge = *(std::min_element(edges.begin(), edges.end()));
	return sqrt3 * min_edge / max_diag ;
	break;
      }


      /**
       * I don't know what to do for this metric.
       * Maybe the base class knows...
       */
    default:
      {
	return Elem::quality(q);
      }
    }


    // Will never get here...
    libmesh_error();
    return 0.;
}
Beispiel #2
0
Real Hex::quality (const ElemQuality q) const
{
  switch (q)
    {

      /**
       * Compue the min/max diagonal ratio.
       * Source: CUBIT User's Manual.
       */
    case DIAGONAL:
      {
        // Diagonal between node 0 and node 6
        const Real d06 = this->length(0,6);

        // Diagonal between node 3 and node 5
        const Real d35 = this->length(3,5);

        // Diagonal between node 1 and node 7
        const Real d17 = this->length(1,7);

        // Diagonal between node 2 and node 4
        const Real d24 = this->length(2,4);

        // Find the biggest and smallest diagonals
        const Real min = std::min(d06, std::min(d35, std::min(d17, d24)));
        const Real max = std::max(d06, std::max(d35, std::max(d17, d24)));

        libmesh_assert_not_equal_to (max, 0.0);

        return min / max;

        break;
      }

      /**
       * Minimum ratio of lengths derived from opposite edges.
       * Source: CUBIT User's Manual.
       */
    case TAPER:
      {

        /**
         * Compute the side lengths.
         */
        const Real d01 = this->length(0,1);
        const Real d12 = this->length(1,2);
        const Real d23 = this->length(2,3);
        const Real d03 = this->length(0,3);
        const Real d45 = this->length(4,5);
        const Real d56 = this->length(5,6);
        const Real d67 = this->length(6,7);
        const Real d47 = this->length(4,7);
        const Real d04 = this->length(0,4);
        const Real d15 = this->length(1,5);
        const Real d37 = this->length(3,7);
        const Real d26 = this->length(2,6);

        std::vector<Real> edge_ratios(12);
        // Front
        edge_ratios[0] = std::min(d01, d45) / std::max(d01, d45);
        edge_ratios[1] = std::min(d04, d15) / std::max(d04, d15);

        // Right
        edge_ratios[2] = std::min(d15, d26) / std::max(d15, d26);
        edge_ratios[3] = std::min(d12, d56) / std::max(d12, d56);

        // Back
        edge_ratios[4] = std::min(d67, d23) / std::max(d67, d23);
        edge_ratios[5] = std::min(d26, d37) / std::max(d26, d37);

        // Left
        edge_ratios[6] = std::min(d04, d37) / std::max(d04, d37);
        edge_ratios[7] = std::min(d03, d47) / std::max(d03, d47);

        // Bottom
        edge_ratios[8] = std::min(d01, d23) / std::max(d01, d23);
        edge_ratios[9] = std::min(d03, d12) / std::max(d03, d12);

        // Top
        edge_ratios[10] = std::min(d45, d67) / std::max(d45, d67);
        edge_ratios[11] = std::min(d56, d47) / std::max(d56, d47);

        return *(std::min_element(edge_ratios.begin(), edge_ratios.end())) ;

        break;
      }


      /**
       * Minimum edge length divided by max diagonal length.
       * Source: CUBIT User's Manual.
       */
    case STRETCH:
      {
        const Real sqrt3 = 1.73205080756888;

        /**
         * Compute the maximum diagonal.
         */
        const Real d06 = this->length(0,6);
        const Real d17 = this->length(1,7);
        const Real d35 = this->length(3,5);
        const Real d24 = this->length(2,4);
        const Real max_diag = std::max(d06, std::max(d17, std::max(d35, d24)));

        libmesh_assert_not_equal_to ( max_diag, 0.0 );

        /**
         * Compute the minimum edge length.
         */
        std::vector<Real> edges(12);
        edges[0]  = this->length(0,1);
        edges[1]  = this->length(1,2);
        edges[2]  = this->length(2,3);
        edges[3]  = this->length(0,3);
        edges[4]  = this->length(4,5);
        edges[5]  = this->length(5,6);
        edges[6]  = this->length(6,7);
        edges[7]  = this->length(4,7);
        edges[8]  = this->length(0,4);
        edges[9]  = this->length(1,5);
        edges[10] = this->length(2,6);
        edges[11] = this->length(3,7);

        const Real min_edge = *(std::min_element(edges.begin(), edges.end()));
        return sqrt3 * min_edge / max_diag ;
      }


      /**
       * I don't know what to do for this metric.
       * Maybe the base class knows...
       */
    default:
      return Elem::quality(q);
    }

  libmesh_error_msg("We'll never get here!");
  return 0.;
}