et_bin_bhns_extr_max.C
/*
* Method of class Et_bin_bhns_extr to search the position of the maximum
* enthalpy
*
* (see file et_bin_bhns_extr.h for documentation).
*
*/
/*
* Copyright (c) 2004 Keisuke Taniguchi
*
* This file is part of LORENE.
*
* LORENE is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* LORENE is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with LORENE; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
char et_bin_bhns_extr_max_C[] = "$Header: /cvsroot/Lorene/C++/Source/Etoile/et_bin_bhns_extr_max.C,v 1.3 2014/10/13 08:52:55 j_novak Exp $" ;
/*
* $Id: et_bin_bhns_extr_max.C,v 1.3 2014/10/13 08:52:55 j_novak Exp $
* $Log: et_bin_bhns_extr_max.C,v $
* Revision 1.3 2014/10/13 08:52:55 j_novak
* Lorene classes and functions now belong to the namespace Lorene.
*
* Revision 1.2 2014/10/06 15:13:07 j_novak
* Modified #include directives to use c++ syntax.
*
* Revision 1.1 2004/11/30 20:50:24 k_taniguchi
* *** empty log message ***
*
*
* $Header: /cvsroot/Lorene/C++/Source/Etoile/et_bin_bhns_extr_max.C,v 1.3 2014/10/13 08:52:55 j_novak Exp $
*
*/
// C headers
#include <cmath>
// Lorene headers
#include "et_bin_bhns_extr.h"
//#include "utilitaires.h"
namespace Lorene {
void Et_bin_bhns_extr::ent_max_search(double& xx, double& yy) const {
//------------------------------------------------------------------//
// Calculate the derivative of the enthalpy field //
//------------------------------------------------------------------//
const Tenseur& dent = ent.gradient() ;
double xxp = 0. ; // Position of the x-coordinate, initialized to zero
double yyp = 0. ; // Position of the y-coordinate, initialized to zero
double xtmp, ytmp ;
int mm, nn ; // Number of steps to the x and y directions
double rr = 0. ; // r coordinate, initialized to zero
double pp = M_PI/2. ; // phi coordinate, initialized to M_PI/2.
double dval_x ; // Direction of dent(0) (1 or -1)
double dval_y ; // Direction of dent(1) (1 or -1)
double ss ;
while ( fabs(dent(0).val_point(rr, M_PI/2., pp)) > 1.e-15 ||
fabs(dent(1).val_point(rr, M_PI/2., pp)) > 5.e-15) {
double dx = 1. ; // Step interval to the x-direction, initialized to 1
double dy = 1. ; // Step interval to the y-direction, initialized to 1
double diff_dent_x ;
double diff_dent_y ;
while ( dy > 1.e-15 ) {
diff_dent_y = 1. ;
nn = 0 ;
dy = 0.1 * dy ;
rr = sqrt( xxp*xxp + yyp*yyp ) ;
if ( xxp == 0. ) {
pp = M_PI/2. ; // There is a possibility of (pp = 1.5*M_PI)
}
else {
pp = acos( xxp / rr ) ;
}
dval_y = dent(1).val_point(rr, M_PI/2., pp) ;
if ( dval_y > 0. ) {
ss = 1. ;
}
else {
ss = -1. ;
}
while( diff_dent_y > 1.e-15 ) {
nn++ ;
ytmp = yyp + ss * nn * dy ;
rr = sqrt( xxp*xxp + ytmp*ytmp ) ;
if ( xxp == 0. ) {
if ( ss > 0. ) {
pp = M_PI/2. ;
}
else {
pp = 1.5*M_PI ;
}
}
else {
pp = acos( xxp / rr ) ;
}
diff_dent_y = ss * dent(1).val_point(rr, M_PI/2., pp) ;
}
yyp += ss * (nn - 1) * dy ;
}
while ( dx > 1.e-15 ) {
diff_dent_x = 1. ;
mm = 0 ;
dx = 0.1 * dx ;
rr = sqrt( xxp*xxp + yyp*yyp ) ;
if ( xxp == 0. ) {
pp = M_PI/2. ; // There is a possibility of (pp = 1.5*M_PI)
}
else {
pp = acos( xxp / rr ) ;
}
dval_x = dent(0).val_point(rr, M_PI/2., pp) ;
if ( dval_x > 0. ) {
ss = 1. ;
}
else {
ss = -1. ;
}
while( diff_dent_x > 1.e-15 ) {
mm++ ;
xtmp = xxp + ss * mm * dx ;
rr = sqrt( xtmp*xtmp + yyp*yyp ) ;
if ( xtmp == 0. ) {
if ( ss > 0. ) {
pp = M_PI/2. ;
}
else {
pp = 1.5*M_PI ;
}
}
else {
pp = acos( xtmp / rr ) ;
}
diff_dent_x = ss * dent(0).val_point(rr, M_PI/2., pp) ;
}
xxp += ss * (mm - 1) * dx ;
}
}
xx = xxp ;
yy = yyp ;
}
}
Lorene::Et_bin_bhns_extr::ent_max_search
void ent_max_search(double &xx, double &yy) const
Searches the position of the maximum enthalpy.
Definition et_bin_bhns_extr_max.C:56
Lorene::Etoile::ent
Tenseur ent
Log-enthalpy (relativistic case) or specific enthalpy (Newtonian case).
Definition etoile.h:457
Lorene::Tenseur
Tensor handling *** DEPRECATED : use class Tensor instead ***.
Definition tenseur.h:301
Lorene::sqrt
Cmp sqrt(const Cmp &)
Square root.
Definition cmp_math.C:220
Lorene::acos
Cmp acos(const Cmp &)
Arccosine.
Definition cmp_math.C:169
Lorene
Lorene prototypes.
Definition app_hor.h:64