[Boost-commit] svn:boost r71909 - sandbox/odeint/branches/karsten/libs/numeric/odeint/ideas/taylor/taylor_v4

Subject: [Boost-commit] svn:boost r71909 - sandbox/odeint/branches/karsten/libs/numeric/odeint/ideas/taylor/taylor_v4
From: karsten.ahnert_at_[hidden]
Date: 2011-05-13 02:58:51

Author: karsten
Date: 2011-05-13 02:58:50 EDT (Fri, 13 May 2011)
New Revision: 71909
URL: http://svn.boost.org/trac/boost/changeset/71909

Log:
introducing the absolute value in taylor controller
Text files modified: 
   sandbox/odeint/branches/karsten/libs/numeric/odeint/ideas/taylor/taylor_v4/taylor.hpp |    10 ++++++----                              
   1 files changed, 6 insertions(+), 4 deletions(-)

Modified: sandbox/odeint/branches/karsten/libs/numeric/odeint/ideas/taylor/taylor_v4/taylor.hpp
==============================================================================
--- sandbox/odeint/branches/karsten/libs/numeric/odeint/ideas/taylor/taylor_v4/taylor.hpp	(original)
+++ sandbox/odeint/branches/karsten/libs/numeric/odeint/ideas/taylor/taylor_v4/taylor.hpp	2011-05-13 02:58:50 EDT (Fri, 13 May 2011)
@@ -392,8 +392,8 @@
         typedef state_type deriv_type;
         typedef std::tr1::array< state_type , order_value > derivs_type;
 
-	taylor( value_type rel_error = 1.0e-14 )
-	: m_derivs() , m_dt_fac( 1.0 ) , m_rel_error( rel_error ) { }
+	taylor( value_type rel_error = 1.0e-14 , value_type abs_error = 1.0e-14 )
+	: m_derivs() , m_dt_fac( 1.0 ) , m_rel_error( rel_error ) , m_abs_error( abs_error ) { }
 
     order_type order( void ) const
     {
@@ -433,11 +433,12 @@
                 double max_error = 0.0;
                 for( size_t i=0 ; i<dim ; ++i )
                 {
-			double error = std::abs( m_derivs[order_value-1][i] ) / ( std::abs( in[i] ) + 1.0e-35 );
+			double error = std::abs( m_derivs[order_value-1][i] ) /
+					( m_rel_error * std::abs( in[i] ) + m_abs_error );
                         max_error = std::max( error , max_error );
                 }
 
-		dt = pow( m_rel_error / max_error , 1.0 / double( order_value ) );
+		dt = pow( 1.0 / max_error , 1.0 / double( order_value ) );
 //		clog << dt << tab << max_error << tab << in[0] << tab << in[1] << tab << in[2] << tab;
 //		clog << m_derivs[0][0] << tab << m_derivs[0][1] << tab << m_derivs[0][2] << tab << m_dt_fac << endl;
 
@@ -542,6 +543,7 @@
         derivs_type m_derivs;
         time_type m_dt_fac;
         value_type m_rel_error;
+	value_type m_abs_error;
 
 };