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#include <cmath> |
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#include "SRI.hpp" |
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QuadraticBend::QuadraticBend( Atom &a, Atom &b, Atom &c ){ |
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set_atoms( a, b, c ); |
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c1 = 0.0; |
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c2 = 0.0; |
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c3 = 0.0; |
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theta0 = 0.0; |
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} |
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void QuadraticBend::setConstants( double the_c1, double the_c2, double the_c3, |
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double the_Th0 ){ |
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c1 = the_c1; |
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c2 = the_c2; |
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c3 = the_c3; |
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theta0 = the_Th0; |
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} |
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|
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double QuadraticBend::bend_force( double theta ){ |
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double dt, dt2; |
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double force; |
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dt = ( theta - theta0 ) * M_PI / 180.0; |
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dt2 = dt * dt; |
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c_potential_E = ( c1 * dt2 ) + ( c2 * dt ) + c3; |
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force = -( ( 2.0 * c1 * dt ) + c2 ); |
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return force; |
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} |