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 (22 years, 7 months ago) by chuckv
File size:	629 byte(s)
Log Message:	Fixes in MPI force calc and in Trappe_Ex parsing.
#	Content
1	#include <cmath>
2
3	#include "SRI.hpp"
4	#include "simError.h"
5
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
30
31
32	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	}