Roszman1               package:NISTnls               R Documentation

_Q_u_a_n_t_u_m _d_e_f_e_c_t_s _i_n _i_o_d_i_n_e

_D_e_s_c_r_i_p_t_i_o_n:

     The `Roszman1' data frame has 25 rows and 2 columns of data on the
     number of quantum defects in iodine atoms at different energy
     states.

_A_r_g_u_m_e_n_t_s:

       y: A numeric vector of number of quantum defects. 

       x: A numeric vector of the excited energy state. 

_F_o_r_m_a_t:

     This data frame contains the following columns:

_D_e_t_a_i_l_s:

     These data are the result of a NIST study involving quantum
     defects in iodine atoms.  The response variable is the number of
     quantum defects, and the predictor variable is the excited energy
     state. The argument to the ARCTAN function is in radians.

_S_o_u_r_c_e:

     Roszman, L., NIST (19??).   Quantum Defects for Sulfur I Atom.

_E_x_a_m_p_l_e_s:

     data(Roszman1)
     plot(y ~ x, data = Roszman1)
     fm1 <- nls(y ~ b1 - b2*x - atan(b3/(x-b4))/pi, data = Roszman1,
                start = c(b1 = 0.1, b2 = -0.00001, b3 = 1000, b4 = -100),
                trace = TRUE)
     fm2 <- nls(y ~ b1 - b2*x - atan(b3/(x-b4))/pi, data = Roszman1,
                start = c(b1 = 0.2, b2 = -0.0000015, b3 = 1200, b4 = -150),
                trace = TRUE)

