test_harm.py 文件源码

def test_energy_individual():
    # Simple test that the individual energies are calculated correctly
    x= numpy.array([-1.1,0.1,1.3])
    v= numpy.array([3.,2.,-5.])
    m= numpy.array([1.,2.,3.])
    omega= 1.1
    E= wendy.energy(x,v,m,individual=True,omega=omega)
    assert numpy.fabs(E[0]-m[0]*v[0]**2./2.-m[0]*(m[1]*numpy.fabs(x[0]-x[1])
                                                  +m[2]*numpy.fabs(x[0]-x[2])
                                                  +omega**2.*x[0]**2./2.)) < 10.**-10
    assert numpy.fabs(E[1]-m[1]*v[1]**2./2.-m[1]*(m[0]*numpy.fabs(x[0]-x[1])
                                                  +m[2]*numpy.fabs(x[2]-x[1])
                                                  +omega**2.*x[1]**2./2.)) < 10.**-10
    assert numpy.fabs(E[2]-m[2]*v[2]**2./2.-m[2]*(m[0]*numpy.fabs(x[0]-x[2])
                                                  +m[1]*numpy.fabs(x[2]-x[1])
                                                  +omega**2.*x[2]**2./2.)) < 10.**-10
    return None