MOAB: Mesh Oriented datABase
(version 5.2.1)
|
00001 /* ***************************************************************** 00002 MESQUITE -- The Mesh Quality Improvement Toolkit 00003 00004 Copyright 2009 Sandia National Laboratories. Developed at the 00005 University of Wisconsin--Madison under SNL contract number 00006 624796. The U.S. Government and the University of Wisconsin 00007 retain certain rights to this software. 00008 00009 This library is free software; you can redistribute it and/or 00010 modify it under the terms of the GNU Lesser General Public 00011 License as published by the Free Software Foundation; either 00012 version 2.1 of the License, or (at your option) any later version. 00013 00014 This library is distributed in the hope that it will be useful, 00015 but WITHOUT ANY WARRANTY; without even the implied warranty of 00016 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00017 Lesser General Public License for more details. 00018 00019 You should have received a copy of the GNU Lesser General Public License 00020 (lgpl.txt) along with this library; if not, write to the Free Software 00021 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 00022 00023 (2009) kraftche@cae.wisc.edu 00024 00025 ***************************************************************** */ 00026 00027 /** \file TUntangle1.cpp 00028 * \brief 00029 * \author Jason Kraftcheck 00030 */ 00031 00032 #include "Mesquite.hpp" 00033 #include "TUntangle1.hpp" 00034 #include "TMPDerivs.hpp" 00035 #include "TMPCommon.hpp" 00036 00037 #include <iostream> 00038 00039 namespace MBMesquite 00040 { 00041 00042 TUntangle1::~TUntangle1() {} 00043 00044 std::string TUntangle1::get_name() const 00045 { 00046 return "Untangle1"; 00047 } 00048 00049 template < unsigned DIM > 00050 inline bool TUntangle1::eval( const MsqMatrix< DIM, DIM >& T, double& result ) 00051 { 00052 double tau = det( T ); 00053 result = 0.5 * ( sqrt( tau * tau + mFactor ) - tau ); 00054 return true; 00055 } 00056 00057 template < unsigned DIM > 00058 inline bool TUntangle1::grad( const MsqMatrix< DIM, DIM >& T, double& result, MsqMatrix< DIM, DIM >& deriv_wrt_T ) 00059 { 00060 double tau = det( T ); 00061 double g = sqrt( tau * tau + mFactor ); 00062 if( g > 1e-50 ) 00063 { 00064 double f = tau / g - 1; 00065 result = 0.5 * ( g - tau ); 00066 deriv_wrt_T = transpose_adj( T ); 00067 deriv_wrt_T *= 0.5 * f; 00068 return true; 00069 } 00070 else 00071 { 00072 std::cout << "Warning: Division by zero avoided in TUntangle1::grad()" << std::endl; 00073 return false; 00074 } 00075 } 00076 00077 template < unsigned DIM > 00078 inline bool TUntangle1::hess( const MsqMatrix< DIM, DIM >& T, double& result, MsqMatrix< DIM, DIM >& deriv_wrt_T, 00079 MsqMatrix< DIM, DIM >* second_wrt_T ) 00080 { 00081 const MsqMatrix< DIM, DIM > adjt = transpose_adj( T ); 00082 double tau = det( T ); 00083 double g = sqrt( tau * tau + mFactor ); 00084 if( g == 0 ) return false; 00085 double f = 0.5 * ( tau / g - 1 ); 00086 result = 0.5 * ( g - tau ); 00087 00088 deriv_wrt_T = adjt; 00089 deriv_wrt_T *= f; 00090 00091 set_scaled_outer_product( second_wrt_T, 0.5 * mFactor / ( g * g * g ), adjt ); 00092 pluseq_scaled_2nd_deriv_of_det( second_wrt_T, f, T ); 00093 00094 return true; 00095 } 00096 00097 TMP_T_TEMPL_IMPL_COMMON( TUntangle1 ) 00098 00099 } // namespace MBMesquite