mdtools/md_code/BendExtensions.cpp

#include <cmath>

#include "SRI.hpp"

QuadraticBend::QuadraticBend( Atom &a, Atom &b, Atom &c ){

  set_atoms( a, b, c );
  c1 = 0.0;
  c2 = 0.0;
  c3 = 0.0;
  theta0 = 0.0;
}

void QuadraticBend::setConstants( double the_c1, double the_c2, double the_c3, 
                                  double the_Th0 ){
  c1 = the_c1;
  c2 = the_c2;
  c3 = the_c3;
  theta0 = the_Th0;
}


double QuadraticBend::bend_force( double theta ){

  double dt, dt2;
  double force;

  dt = ( theta - theta0 ) * M_PI / 180.0;
  dt2 = dt * dt;

  c_potential_E = ( c1 * dt2 ) + ( c2 * dt ) + c3;
  force = -( ( 2.0 * c1 * dt ) + c2 );
  return force;
}
Revision:	10
Committed:	Tue Jul 9 18:40:59 2002 UTC (22 years ago) by mmeineke
Original Path:	*branches/mmeineke/mdtools/md_code/BendExtensions.cpp*
File size:	604 byte(s)
Log Message:	everything you need to make libmdtools
#	User	Rev	Content
1	mmeineke	10	#include <cmath>
2
3			#include "SRI.hpp"
4
5			QuadraticBend::QuadraticBend( Atom &a, Atom &b, Atom &c ){
6
7			set_atoms( a, b, c );
8			c1 = 0.0;
9			c2 = 0.0;
10			c3 = 0.0;
11			theta0 = 0.0;
12			}
13
14			void QuadraticBend::setConstants( double the_c1, double the_c2, double the_c3,
15			double the_Th0 ){
16			c1 = the_c1;
17			c2 = the_c2;
18			c3 = the_c3;
19			theta0 = the_Th0;
20			}
21
22
23			double QuadraticBend::bend_force( double theta ){
24
25			double dt, dt2;
26			double force;
27
28			dt = ( theta - theta0 ) * M_PI / 180.0;
29			dt2 = dt * dt;
30
31			c_potential_E = ( c1 * dt2 ) + ( c2 * dt ) + c3;
32			force = -( ( 2.0 * c1 * dt ) + c2 );
33			return force;
34			}