domain_oned_inf_ope.cpp

/*
    Copyright 2017 Philippe Grandclement
 
    This file is part of Kadath.
 
    Kadath is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
 
    Kadath 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 Kadath.  If not, see <http://www.gnu.org/licenses/>.
*/
 
#include "headcpp.hpp"
#include "utilities.hpp"
#include "oned.hpp"
#include "array_math.hpp"
#include "val_domain.hpp"
namespace Kadath {
int mult_xm1_1d (int, Array<double>&) ;
int div_xm1_1d (int, Array<double>&) ;
 
Val_domain Domain_oned_inf::mult_xm1 (const Val_domain& so) const {
    so.coef() ;
    Val_domain res(this) ;
 
    res.base= so.base ;
    
    res.cf = new Array<double> (so.base.ope_1d(mult_xm1_1d, 0, *so.cf, res.base)) ;
    res.in_coef = true ;
    return res ;
}
 
Val_domain Domain_oned_inf::der_partial_var (const Val_domain& so, int which_var) const {
 
    switch (which_var) {
        case 0 :
            return -alpha*so.der_var(1).mult_xm1().mult_xm1() ;
            break ;
        default:
            cerr << "Unknown variable in Domain_oned_inf::der_partial_var" << endl ;
            abort() ;
        }
}
 
Val_domain Domain_oned_inf::div_xm1 (const Val_domain& so) const {
    so.coef() ;
    Val_domain res(this) ;
 
    res.base = so.base ;    
    
    res.cf = new Array<double> (so.base.ope_1d(div_xm1_1d, 0, *so.cf, res.base)) ;
    res.in_coef = true ;
    return res ;
}
 
Val_domain Domain_oned_inf::mult_x (const Val_domain& so) const {
    so.coef() ;
    Val_domain res(div_xm1(so)) ;
    res /= alpha ;
    return res ;
}
 
 
double Domain_oned_inf::integrale (const Val_domain& so) const {
    double res = 0 ;
    Val_domain integrant (div_xm1(div_xm1(so))) ;
    integrant.coef() ;
    int baser = (*integrant.get_base().bases_1d[0]) (0) ;
    
    switch (baser) {
      case CHEB :
    for (int i=0 ; i<nbr_coefs(0) ; i+=2)
        res += integrant.get_coef()(i)*(1./double(i+1) - 1./double(i-1)) ;
    break ;
      default : 
     cerr << "Case not implemented in Domain_oned_inf::integrale" << endl ;
    }
    return -res/alpha ;
}}