def test_EulerCromer():
    """
    This test checks that the Euler Cromer method is correctly updating a particle's position and
    velocity.
    """
    proton = Particle('proton', const.m_p, [0,0,0], [-100,200,300], [10,20,-30])
    deltaT = 0.5
    calculated_velocity = np.array([-95,210,285], dtype=float)
    calculated_position = np.array([-47.5,105,142.5], dtype=float)
    proton.eulerCromer(deltaT)
    assert np.array_equal(calculated_velocity,proton.velocity)
    assert np.array_equal(calculated_position,proton.position)