OOPSE/libmdtools/BendExtensions.cpp

#include <cmath>

#include "SRI.hpp"
#include "simError.h"

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:	438
Committed:	Mon Mar 31 21:50:59 2003 UTC (21 years, 3 months ago) by chuckv
File size:	629 byte(s)
Log Message:	Fixes in MPI force calc and in Trappe_Ex parsing.
#	User	Rev	Content
1	mmeineke	377	#include <cmath>
2
3			#include "SRI.hpp"
4	chuckv	438	#include "simError.h"
5	mmeineke	377
6			QuadraticBend::QuadraticBend( Atom &a, Atom &b, Atom &c ){
7
8			set_atoms( a, b, c );
9			c1 = 0.0;
10			c2 = 0.0;
11			c3 = 0.0;
12			theta0 = 0.0;
13			}
14
15			void QuadraticBend::setConstants( double the_c1, double the_c2, double the_c3,
16			double the_Th0 ){
17			c1 = the_c1;
18			c2 = the_c2;
19			c3 = the_c3;
20			theta0 = the_Th0;
21			}
22
23
24			double QuadraticBend::bend_force( double theta ){
25
26			double dt, dt2;
27			double force;
28
29	chuckv	438
30
31
32	mmeineke	377	dt = ( theta - theta0 ) * M_PI / 180.0;
33			dt2 = dt * dt;
34
35			c_potential_E = ( c1 * dt2 ) + ( c2 * dt ) + c3;
36			force = -( ( 2.0 * c1 * dt ) + c2 );
37			return force;
38			}